Merge remote-tracking branch 'remotes/fslc/4.9-2.3.x-imx' into toradex_4.9-2.3.x-imx-next

Conflicts:
	sound/soc/codecs/sgtl5000.c
	sound/soc/fsl/imx-sgtl5000.c

71 files changed, 1114 insertions, 530 deletions

diff --git a/kernel/Makefile b/kernel/Makefile
index 314e7d62f5f0..184fa9aa5802 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -28,6 +28,7 @@ KCOV_INSTRUMENT_extable.o := n
 # Don't self-instrument.
 KCOV_INSTRUMENT_kcov.o := n
 KASAN_SANITIZE_kcov.o := n
+CFLAGS_kcov.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector)
 
 # cond_syscall is currently not LTO compatible
 CFLAGS_sys_ni.o = $(DISABLE_LTO)
diff --git a/kernel/audit.c b/kernel/audit.c
index 3461a3d874fe..53dcaa3b67bc 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -751,13 +751,11 @@ static void audit_log_feature_change(int which, u32 old_feature, u32 new_feature
 	audit_log_end(ab);
 }
 
-static int audit_set_feature(struct sk_buff *skb)
+static int audit_set_feature(struct audit_features *uaf)
 {
-	struct audit_features *uaf;
 	int i;
 
 	BUILD_BUG_ON(AUDIT_LAST_FEATURE + 1 > ARRAY_SIZE(audit_feature_names));
-	uaf = nlmsg_data(nlmsg_hdr(skb));
 
 	/* if there is ever a version 2 we should handle that here */
 
@@ -823,6 +821,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	u32			seq;
 	void			*data;
+	int			data_len;
 	int			err;
 	struct audit_buffer	*ab;
 	u16			msg_type = nlh->nlmsg_type;
@@ -846,6 +845,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 	}
 	seq  = nlh->nlmsg_seq;
 	data = nlmsg_data(nlh);
+	data_len = nlmsg_len(nlh);
 
 	switch (msg_type) {
 	case AUDIT_GET: {
@@ -867,7 +867,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 		struct audit_status	s;
 		memset(&s, 0, sizeof(s));
 		/* guard against past and future API changes */
-		memcpy(&s, data, min_t(size_t, sizeof(s), nlmsg_len(nlh)));
+		memcpy(&s, data, min_t(size_t, sizeof(s), data_len));
 		if (s.mask & AUDIT_STATUS_ENABLED) {
 			err = audit_set_enabled(s.enabled);
 			if (err < 0)
@@ -930,7 +930,9 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 			return err;
 		break;
 	case AUDIT_SET_FEATURE:
-		err = audit_set_feature(skb);
+		if (data_len < sizeof(struct audit_features))
+			return -EINVAL;
+		err = audit_set_feature(data);
 		if (err)
 			return err;
 		break;
@@ -942,6 +944,8 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 
 		err = audit_filter(msg_type, AUDIT_FILTER_USER);
 		if (err == 1) { /* match or error */
+			char *str = data;
+
 			err = 0;
 			if (msg_type == AUDIT_USER_TTY) {
 				err = tty_audit_push();
@@ -950,19 +954,17 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 			}
 			mutex_unlock(&audit_cmd_mutex);
 			audit_log_common_recv_msg(&ab, msg_type);
-			if (msg_type != AUDIT_USER_TTY)
+			if (msg_type != AUDIT_USER_TTY) {
+				/* ensure NULL termination */
+				str[data_len - 1] = '\0';
 				audit_log_format(ab, " msg='%.*s'",
 						 AUDIT_MESSAGE_TEXT_MAX,
-						 (char *)data);
-			else {
-				int size;
-
+						 str);
+			} else {
 				audit_log_format(ab, " data=");
-				size = nlmsg_len(nlh);
-				if (size > 0 &&
-				    ((unsigned char *)data)[size - 1] == '\0')
-					size--;
-				audit_log_n_untrustedstring(ab, data, size);
+				if (data_len > 0 && str[data_len - 1] == '\0')
+					data_len--;
+				audit_log_n_untrustedstring(ab, str, data_len);
 			}
 			audit_set_portid(ab, NETLINK_CB(skb).portid);
 			audit_log_end(ab);
@@ -971,7 +973,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 		break;
 	case AUDIT_ADD_RULE:
 	case AUDIT_DEL_RULE:
-		if (nlmsg_len(nlh) < sizeof(struct audit_rule_data))
+		if (data_len < sizeof(struct audit_rule_data))
 			return -EINVAL;
 		if (audit_enabled == AUDIT_LOCKED) {
 			audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE);
@@ -980,7 +982,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 			return -EPERM;
 		}
 		err = audit_rule_change(msg_type, NETLINK_CB(skb).portid,
-					   seq, data, nlmsg_len(nlh));
+					   seq, data, data_len);
 		break;
 	case AUDIT_LIST_RULES:
 		err = audit_list_rules_send(skb, seq);
@@ -994,7 +996,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 	case AUDIT_MAKE_EQUIV: {
 		void *bufp = data;
 		u32 sizes[2];
-		size_t msglen = nlmsg_len(nlh);
+		size_t msglen = data_len;
 		char *old, *new;
 
 		err = -EINVAL;
@@ -1070,7 +1072,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 
 		memset(&s, 0, sizeof(s));
 		/* guard against past and future API changes */
-		memcpy(&s, data, min_t(size_t, sizeof(s), nlmsg_len(nlh)));
+		memcpy(&s, data, min_t(size_t, sizeof(s), data_len));
 		/* check if new data is valid */
 		if ((s.enabled != 0 && s.enabled != 1) ||
 		    (s.log_passwd != 0 && s.log_passwd != 1))
diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c
index f036b6ada6ef..712469a3103a 100644
--- a/kernel/audit_watch.c
+++ b/kernel/audit_watch.c
@@ -365,12 +365,12 @@ static int audit_get_nd(struct audit_watch *watch, struct path *parent)
 	struct dentry *d = kern_path_locked(watch->path, parent);
 	if (IS_ERR(d))
 		return PTR_ERR(d);
-	inode_unlock(d_backing_inode(parent->dentry));
 	if (d_is_positive(d)) {
 		/* update watch filter fields */
 		watch->dev = d->d_sb->s_dev;
 		watch->ino = d_backing_inode(d)->i_ino;
 	}
+	inode_unlock(d_backing_inode(parent->dentry));
 	dput(d);
 	return 0;
 }
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index cd4f41397c7e..a71ff9965cba 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -434,6 +434,7 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
 	bufp = data->buf;
 	for (i = 0; i < data->field_count; i++) {
 		struct audit_field *f = &entry->rule.fields[i];
+		u32 f_val;
 
 		err = -EINVAL;
 
@@ -442,12 +443,12 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
 			goto exit_free;
 
 		f->type = data->fields[i];
-		f->val = data->values[i];
+		f_val = data->values[i];
 
 		/* Support legacy tests for a valid loginuid */
-		if ((f->type == AUDIT_LOGINUID) && (f->val == AUDIT_UID_UNSET)) {
+		if ((f->type == AUDIT_LOGINUID) && (f_val == AUDIT_UID_UNSET)) {
 			f->type = AUDIT_LOGINUID_SET;
-			f->val = 0;
+			f_val = 0;
 			entry->rule.pflags |= AUDIT_LOGINUID_LEGACY;
 		}
 
@@ -463,7 +464,7 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
 		case AUDIT_SUID:
 		case AUDIT_FSUID:
 		case AUDIT_OBJ_UID:
-			f->uid = make_kuid(current_user_ns(), f->val);
+			f->uid = make_kuid(current_user_ns(), f_val);
 			if (!uid_valid(f->uid))
 				goto exit_free;
 			break;
@@ -472,11 +473,12 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
 		case AUDIT_SGID:
 		case AUDIT_FSGID:
 		case AUDIT_OBJ_GID:
-			f->gid = make_kgid(current_user_ns(), f->val);
+			f->gid = make_kgid(current_user_ns(), f_val);
 			if (!gid_valid(f->gid))
 				goto exit_free;
 			break;
 		case AUDIT_ARCH:
+			f->val = f_val;
 			entry->rule.arch_f = f;
 			break;
 		case AUDIT_SUBJ_USER:
@@ -489,11 +491,13 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
 		case AUDIT_OBJ_TYPE:
 		case AUDIT_OBJ_LEV_LOW:
 		case AUDIT_OBJ_LEV_HIGH:
-			str = audit_unpack_string(&bufp, &remain, f->val);
-			if (IS_ERR(str))
+			str = audit_unpack_string(&bufp, &remain, f_val);
+			if (IS_ERR(str)) {
+				err = PTR_ERR(str);
 				goto exit_free;
-			entry->rule.buflen += f->val;
-
+			}
+			entry->rule.buflen += f_val;
+			f->lsm_str = str;
 			err = security_audit_rule_init(f->type, f->op, str,
 						       (void **)&f->lsm_rule);
 			/* Keep currently invalid fields around in case they
@@ -502,68 +506,71 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
 				pr_warn("audit rule for LSM \'%s\' is invalid\n",
 					str);
 				err = 0;
-			}
-			if (err) {
-				kfree(str);
+			} else if (err)
 				goto exit_free;
-			} else
-				f->lsm_str = str;
 			break;
 		case AUDIT_WATCH:
-			str = audit_unpack_string(&bufp, &remain, f->val);
-			if (IS_ERR(str))
+			str = audit_unpack_string(&bufp, &remain, f_val);
+			if (IS_ERR(str)) {
+				err = PTR_ERR(str);
 				goto exit_free;
-			entry->rule.buflen += f->val;
-
-			err = audit_to_watch(&entry->rule, str, f->val, f->op);
+			}
+			err = audit_to_watch(&entry->rule, str, f_val, f->op);
 			if (err) {
 				kfree(str);
 				goto exit_free;
 			}
+			entry->rule.buflen += f_val;
 			break;
 		case AUDIT_DIR:
-			str = audit_unpack_string(&bufp, &remain, f->val);
-			if (IS_ERR(str))
+			str = audit_unpack_string(&bufp, &remain, f_val);
+			if (IS_ERR(str)) {
+				err = PTR_ERR(str);
 				goto exit_free;
-			entry->rule.buflen += f->val;
-
+			}
 			err = audit_make_tree(&entry->rule, str, f->op);
 			kfree(str);
 			if (err)
 				goto exit_free;
+			entry->rule.buflen += f_val;
 			break;
 		case AUDIT_INODE:
+			f->val = f_val;
 			err = audit_to_inode(&entry->rule, f);
 			if (err)
 				goto exit_free;
 			break;
 		case AUDIT_FILTERKEY:
-			if (entry->rule.filterkey || f->val > AUDIT_MAX_KEY_LEN)
+			if (entry->rule.filterkey || f_val > AUDIT_MAX_KEY_LEN)
 				goto exit_free;
-			str = audit_unpack_string(&bufp, &remain, f->val);
-			if (IS_ERR(str))
+			str = audit_unpack_string(&bufp, &remain, f_val);
+			if (IS_ERR(str)) {
+				err = PTR_ERR(str);
 				goto exit_free;
-			entry->rule.buflen += f->val;
+			}
+			entry->rule.buflen += f_val;
 			entry->rule.filterkey = str;
 			break;
 		case AUDIT_EXE:
-			if (entry->rule.exe || f->val > PATH_MAX)
+			if (entry->rule.exe || f_val > PATH_MAX)
 				goto exit_free;
-			str = audit_unpack_string(&bufp, &remain, f->val);
+			str = audit_unpack_string(&bufp, &remain, f_val);
 			if (IS_ERR(str)) {
 				err = PTR_ERR(str);
 				goto exit_free;
 			}
-			entry->rule.buflen += f->val;
-
-			audit_mark = audit_alloc_mark(&entry->rule, str, f->val);
+			audit_mark = audit_alloc_mark(&entry->rule, str, f_val);
 			if (IS_ERR(audit_mark)) {
 				kfree(str);
 				err = PTR_ERR(audit_mark);
 				goto exit_free;
 			}
+			entry->rule.buflen += f_val;
 			entry->rule.exe = audit_mark;
 			break;
+		default:
+			f->val = f_val;
+			break;
 		}
 	}
 
@@ -1095,22 +1102,24 @@ int audit_rule_change(int type, __u32 portid, int seq, void *data,
 	int err = 0;
 	struct audit_entry *entry;
 
-	entry = audit_data_to_entry(data, datasz);
-	if (IS_ERR(entry))
-		return PTR_ERR(entry);
-
 	switch (type) {
 	case AUDIT_ADD_RULE:
+		entry = audit_data_to_entry(data, datasz);
+		if (IS_ERR(entry))
+			return PTR_ERR(entry);
 		err = audit_add_rule(entry);
 		audit_log_rule_change("add_rule", &entry->rule, !err);
 		break;
 	case AUDIT_DEL_RULE:
+		entry = audit_data_to_entry(data, datasz);
+		if (IS_ERR(entry))
+			return PTR_ERR(entry);
 		err = audit_del_rule(entry);
 		audit_log_rule_change("remove_rule", &entry->rule, !err);
 		break;
 	default:
-		err = -EINVAL;
 		WARN_ON(1);
+		return -EINVAL;
 	}
 
 	if (err || type == AUDIT_DEL_RULE) {
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index c2aaf539728f..854e90be1a02 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -1096,7 +1096,7 @@ static void audit_log_execve_info(struct audit_context *context,
 		}
 
 		/* write as much as we can to the audit log */
-		if (len_buf > 0) {
+		if (len_buf >= 0) {
 			/* NOTE: some magic numbers here - basically if we
 			 *       can't fit a reasonable amount of data into the
 			 *       existing audit buffer, flush it and start with
diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile
index eed911d091da..5a590f22b4d4 100644
--- a/kernel/bpf/Makefile
+++ b/kernel/bpf/Makefile
@@ -1,4 +1,5 @@
 obj-y := core.o
+CFLAGS_core.o += $(call cc-disable-warning, override-init)
 
 obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o
 obj-$(CONFIG_BPF_SYSCALL) += hashtab.o arraymap.o percpu_freelist.o
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 879ca844ba1d..df2ebce927ec 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -208,27 +208,80 @@ struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off,
 }
 
 #ifdef CONFIG_BPF_JIT
+/* All BPF JIT sysctl knobs here. */
+int bpf_jit_enable   __read_mostly = IS_BUILTIN(CONFIG_BPF_JIT_ALWAYS_ON);
+int bpf_jit_harden   __read_mostly;
+long bpf_jit_limit   __read_mostly;
+
+static atomic_long_t bpf_jit_current;
+
+/* Can be overridden by an arch's JIT compiler if it has a custom,
+ * dedicated BPF backend memory area, or if neither of the two
+ * below apply.
+ */
+u64 __weak bpf_jit_alloc_exec_limit(void)
+{
+#if defined(MODULES_VADDR)
+	return MODULES_END - MODULES_VADDR;
+#else
+	return VMALLOC_END - VMALLOC_START;
+#endif
+}
+
+static int __init bpf_jit_charge_init(void)
+{
+	/* Only used as heuristic here to derive limit. */
+	bpf_jit_limit = min_t(u64, round_up(bpf_jit_alloc_exec_limit() >> 2,
+					    PAGE_SIZE), LONG_MAX);
+	return 0;
+}
+pure_initcall(bpf_jit_charge_init);
+
+static int bpf_jit_charge_modmem(u32 pages)
+{
+	if (atomic_long_add_return(pages, &bpf_jit_current) >
+	    (bpf_jit_limit >> PAGE_SHIFT)) {
+		if (!capable(CAP_SYS_ADMIN)) {
+			atomic_long_sub(pages, &bpf_jit_current);
+			return -EPERM;
+		}
+	}
+
+	return 0;
+}
+
+static void bpf_jit_uncharge_modmem(u32 pages)
+{
+	atomic_long_sub(pages, &bpf_jit_current);
+}
+
 struct bpf_binary_header *
 bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr,
 		     unsigned int alignment,
 		     bpf_jit_fill_hole_t bpf_fill_ill_insns)
 {
 	struct bpf_binary_header *hdr;
-	unsigned int size, hole, start;
+	u32 size, hole, start, pages;
 
 	/* Most of BPF filters are really small, but if some of them
 	 * fill a page, allow at least 128 extra bytes to insert a
 	 * random section of illegal instructions.
 	 */
 	size = round_up(proglen + sizeof(*hdr) + 128, PAGE_SIZE);
+	pages = size / PAGE_SIZE;
+
+	if (bpf_jit_charge_modmem(pages))
+		return NULL;
 	hdr = module_alloc(size);
-	if (hdr == NULL)
+	if (!hdr) {
+		bpf_jit_uncharge_modmem(pages);
 		return NULL;
+	}
 
 	/* Fill space with illegal/arch-dep instructions. */
 	bpf_fill_ill_insns(hdr, size);
 
-	hdr->pages = size / PAGE_SIZE;
+	hdr->pages = pages;
 	hole = min_t(unsigned int, size - (proglen + sizeof(*hdr)),
 		     PAGE_SIZE - sizeof(*hdr));
 	start = (get_random_int() % hole) & ~(alignment - 1);
@@ -241,11 +294,12 @@ bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr,
 
 void bpf_jit_binary_free(struct bpf_binary_header *hdr)
 {
+	u32 pages = hdr->pages;
+
 	module_memfree(hdr);
+	bpf_jit_uncharge_modmem(pages);
 }
 
-int bpf_jit_harden __read_mostly;
-
 static int bpf_jit_blind_insn(const struct bpf_insn *from,
 			      const struct bpf_insn *aux,
 			      struct bpf_insn *to_buff)
@@ -925,8 +979,13 @@ load_byte:
 STACK_FRAME_NON_STANDARD(__bpf_prog_run); /* jump table */
 
 #else
-static unsigned int __bpf_prog_ret0(void *ctx, const struct bpf_insn *insn)
+static unsigned int __bpf_prog_ret0_warn(void *ctx,
+					 const struct bpf_insn *insn)
 {
+	/* If this handler ever gets executed, then BPF_JIT_ALWAYS_ON
+	 * is not working properly, so warn about it!
+	 */
+	WARN_ON_ONCE(1);
 	return 0;
 }
 #endif
@@ -981,7 +1040,7 @@ struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err)
 #ifndef CONFIG_BPF_JIT_ALWAYS_ON
 	fp->bpf_func = (void *) __bpf_prog_run;
 #else
-	fp->bpf_func = (void *) __bpf_prog_ret0;
+	fp->bpf_func = (void *) __bpf_prog_ret0_warn;
 #endif
 
 	/* eBPF JITs can rewrite the program in case constant
diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c
index a36a532c056d..8648d7d29708 100644
--- a/kernel/bpf/hashtab.c
+++ b/kernel/bpf/hashtab.c
@@ -13,10 +13,11 @@
 #include <linux/bpf.h>
 #include <linux/jhash.h>
 #include <linux/filter.h>
+#include <linux/rculist_nulls.h>
 #include "percpu_freelist.h"
 
 struct bucket {
-	struct hlist_head head;
+	struct hlist_nulls_head head;
 	raw_spinlock_t lock;
 };
 
@@ -40,9 +41,14 @@ enum extra_elem_state {
 /* each htab element is struct htab_elem + key + value */
 struct htab_elem {
 	union {
-		struct hlist_node hash_node;
-		struct bpf_htab *htab;
-		struct pcpu_freelist_node fnode;
+		struct hlist_nulls_node hash_node;
+		struct {
+			void *padding;
+			union {
+				struct bpf_htab *htab;
+				struct pcpu_freelist_node fnode;
+			};
+		};
 	};
 	union {
 		struct rcu_head rcu;
@@ -114,8 +120,10 @@ skip_percpu_elems:
 	if (err)
 		goto free_elems;
 
-	pcpu_freelist_populate(&htab->freelist, htab->elems, htab->elem_size,
-			       htab->map.max_entries);
+	pcpu_freelist_populate(&htab->freelist,
+			       htab->elems + offsetof(struct htab_elem, fnode),
+			       htab->elem_size, htab->map.max_entries);
+
 	return 0;
 
 free_elems:
@@ -148,6 +156,11 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
 	int err, i;
 	u64 cost;
 
+	BUILD_BUG_ON(offsetof(struct htab_elem, htab) !=
+		     offsetof(struct htab_elem, hash_node.pprev));
+	BUILD_BUG_ON(offsetof(struct htab_elem, fnode.next) !=
+		     offsetof(struct htab_elem, hash_node.pprev));
+
 	if (attr->map_flags & ~BPF_F_NO_PREALLOC)
 		/* reserved bits should not be used */
 		return ERR_PTR(-EINVAL);
@@ -233,7 +246,7 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
 		goto free_htab;
 
 	for (i = 0; i < htab->n_buckets; i++) {
-		INIT_HLIST_HEAD(&htab->buckets[i].head);
+		INIT_HLIST_NULLS_HEAD(&htab->buckets[i].head, i);
 		raw_spin_lock_init(&htab->buckets[i].lock);
 	}
 
@@ -270,20 +283,44 @@ static inline struct bucket *__select_bucket(struct bpf_htab *htab, u32 hash)
 	return &htab->buckets[hash & (htab->n_buckets - 1)];
 }
 
-static inline struct hlist_head *select_bucket(struct bpf_htab *htab, u32 hash)
+static inline struct hlist_nulls_head *select_bucket(struct bpf_htab *htab, u32 hash)
 {
 	return &__select_bucket(htab, hash)->head;
 }
 
-static struct htab_elem *lookup_elem_raw(struct hlist_head *head, u32 hash,
+/* this lookup function can only be called with bucket lock taken */
+static struct htab_elem *lookup_elem_raw(struct hlist_nulls_head *head, u32 hash,
 					 void *key, u32 key_size)
 {
+	struct hlist_nulls_node *n;
+	struct htab_elem *l;
+
+	hlist_nulls_for_each_entry_rcu(l, n, head, hash_node)
+		if (l->hash == hash && !memcmp(&l->key, key, key_size))
+			return l;
+
+	return NULL;
+}
+
+/* can be called without bucket lock. it will repeat the loop in
+ * the unlikely event when elements moved from one bucket into another
+ * while link list is being walked
+ */
+static struct htab_elem *lookup_nulls_elem_raw(struct hlist_nulls_head *head,
+					       u32 hash, void *key,
+					       u32 key_size, u32 n_buckets)
+{
+	struct hlist_nulls_node *n;
 	struct htab_elem *l;
 
-	hlist_for_each_entry_rcu(l, head, hash_node)
+again:
+	hlist_nulls_for_each_entry_rcu(l, n, head, hash_node)
 		if (l->hash == hash && !memcmp(&l->key, key, key_size))
 			return l;
 
+	if (unlikely(get_nulls_value(n) != (hash & (n_buckets - 1))))
+		goto again;
+
 	return NULL;
 }
 
@@ -291,7 +328,7 @@ static struct htab_elem *lookup_elem_raw(struct hlist_head *head, u32 hash,
 static void *__htab_map_lookup_elem(struct bpf_map *map, void *key)
 {
 	struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
-	struct hlist_head *head;
+	struct hlist_nulls_head *head;
 	struct htab_elem *l;
 	u32 hash, key_size;
 
@@ -304,7 +341,7 @@ static void *__htab_map_lookup_elem(struct bpf_map *map, void *key)
 
 	head = select_bucket(htab, hash);
 
-	l = lookup_elem_raw(head, hash, key, key_size);
+	l = lookup_nulls_elem_raw(head, hash, key, key_size, htab->n_buckets);
 
 	return l;
 }
@@ -323,7 +360,7 @@ static void *htab_map_lookup_elem(struct bpf_map *map, void *key)
 static int htab_map_get_next_key(struct bpf_map *map, void *key, void *next_key)
 {
 	struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
-	struct hlist_head *head;
+	struct hlist_nulls_head *head;
 	struct htab_elem *l, *next_l;
 	u32 hash, key_size;
 	int i = 0;
@@ -340,13 +377,13 @@ static int htab_map_get_next_key(struct bpf_map *map, void *key, void *next_key)
 	head = select_bucket(htab, hash);
 
 	/* lookup the key */
-	l = lookup_elem_raw(head, hash, key, key_size);
+	l = lookup_nulls_elem_raw(head, hash, key, key_size, htab->n_buckets);
 
 	if (!l)
 		goto find_first_elem;
 
 	/* key was found, get next key in the same bucket */
-	next_l = hlist_entry_safe(rcu_dereference_raw(hlist_next_rcu(&l->hash_node)),
+	next_l = hlist_nulls_entry_safe(rcu_dereference_raw(hlist_nulls_next_rcu(&l->hash_node)),
 				  struct htab_elem, hash_node);
 
 	if (next_l) {
@@ -365,7 +402,7 @@ find_first_elem:
 		head = select_bucket(htab, i);
 
 		/* pick first element in the bucket */
-		next_l = hlist_entry_safe(rcu_dereference_raw(hlist_first_rcu(head)),
+		next_l = hlist_nulls_entry_safe(rcu_dereference_raw(hlist_nulls_first_rcu(head)),
 					  struct htab_elem, hash_node);
 		if (next_l) {
 			/* if it's not empty, just return it */
@@ -429,9 +466,13 @@ static struct htab_elem *alloc_htab_elem(struct bpf_htab *htab, void *key,
 	int err = 0;
 
 	if (prealloc) {
-		l_new = (struct htab_elem *)pcpu_freelist_pop(&htab->freelist);
-		if (!l_new)
+		struct pcpu_freelist_node *l;
+
+		l = pcpu_freelist_pop(&htab->freelist);
+		if (!l)
 			err = -E2BIG;
+		else
+			l_new = container_of(l, struct htab_elem, fnode);
 	} else {
 		if (atomic_inc_return(&htab->count) > htab->map.max_entries) {
 			atomic_dec(&htab->count);
@@ -518,7 +559,7 @@ static int htab_map_update_elem(struct bpf_map *map, void *key, void *value,
 {
 	struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
 	struct htab_elem *l_new = NULL, *l_old;
-	struct hlist_head *head;
+	struct hlist_nulls_head *head;
 	unsigned long flags;
 	struct bucket *b;
 	u32 key_size, hash;
@@ -557,9 +598,9 @@ static int htab_map_update_elem(struct bpf_map *map, void *key, void *value,
 	/* add new element to the head of the list, so that
 	 * concurrent search will find it before old elem
 	 */
-	hlist_add_head_rcu(&l_new->hash_node, head);
+	hlist_nulls_add_head_rcu(&l_new->hash_node, head);
 	if (l_old) {
-		hlist_del_rcu(&l_old->hash_node);
+		hlist_nulls_del_rcu(&l_old->hash_node);
 		free_htab_elem(htab, l_old);
 	}
 	ret = 0;
@@ -574,7 +615,7 @@ static int __htab_percpu_map_update_elem(struct bpf_map *map, void *key,
 {
 	struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
 	struct htab_elem *l_new = NULL, *l_old;
-	struct hlist_head *head;
+	struct hlist_nulls_head *head;
 	unsigned long flags;
 	struct bucket *b;
 	u32 key_size, hash;
@@ -626,7 +667,7 @@ static int __htab_percpu_map_update_elem(struct bpf_map *map, void *key,
 			ret = PTR_ERR(l_new);
 			goto err;
 		}
-		hlist_add_head_rcu(&l_new->hash_node, head);
+		hlist_nulls_add_head_rcu(&l_new->hash_node, head);
 	}
 	ret = 0;
 err:
@@ -644,7 +685,7 @@ static int htab_percpu_map_update_elem(struct bpf_map *map, void *key,
 static int htab_map_delete_elem(struct bpf_map *map, void *key)
 {
 	struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
-	struct hlist_head *head;
+	struct hlist_nulls_head *head;
 	struct bucket *b;
 	struct htab_elem *l;
 	unsigned long flags;
@@ -664,7 +705,7 @@ static int htab_map_delete_elem(struct bpf_map *map, void *key)
 	l = lookup_elem_raw(head, hash, key, key_size);
 
 	if (l) {
-		hlist_del_rcu(&l->hash_node);
+		hlist_nulls_del_rcu(&l->hash_node);
 		free_htab_elem(htab, l);
 		ret = 0;
 	}
@@ -678,12 +719,12 @@ static void delete_all_elements(struct bpf_htab *htab)
 	int i;
 
 	for (i = 0; i < htab->n_buckets; i++) {
-		struct hlist_head *head = select_bucket(htab, i);
-		struct hlist_node *n;
+		struct hlist_nulls_head *head = select_bucket(htab, i);
+		struct hlist_nulls_node *n;
 		struct htab_elem *l;
 
-		hlist_for_each_entry_safe(l, n, head, hash_node) {
-			hlist_del_rcu(&l->hash_node);
+		hlist_nulls_for_each_entry_safe(l, n, head, hash_node) {
+			hlist_nulls_del_rcu(&l->hash_node);
 			if (l->state != HTAB_EXTRA_ELEM_USED)
 				htab_elem_free(htab, l);
 		}
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index ca7e277e8b5f..e10314223cbf 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -802,7 +802,7 @@ static int bpf_obj_get(const union bpf_attr *attr)
 
 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
 {
-	union bpf_attr attr = {};
+	union bpf_attr attr;
 	int err;
 
 	if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN))
@@ -838,6 +838,7 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, siz
 	}
 
 	/* copy attributes from user space, may be less than sizeof(bpf_attr) */
+	memset(&attr, 0, sizeof(attr));
 	if (copy_from_user(&attr, uattr, size) != 0)
 		return -EFAULT;
 
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index bb0cf1caf1cd..2d7a4fc42a88 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -6335,6 +6335,10 @@ void cgroup_sk_alloc(struct sock_cgroup_data *skcd)
 		return;
 	}
 
+	/* Don't associate the sock with unrelated interrupted task's cgroup. */
+	if (in_interrupt())
+		return;
+
 	rcu_read_lock();
 
 	while (true) {
diff --git a/kernel/cgroup_pids.c b/kernel/cgroup_pids.c
index a57242e0d5a6..b8b898e21c19 100644
--- a/kernel/cgroup_pids.c
+++ b/kernel/cgroup_pids.c
@@ -48,7 +48,7 @@ struct pids_cgroup {
 	 * %PIDS_MAX = (%PID_MAX_LIMIT + 1).
 	 */
 	atomic64_t			counter;
-	int64_t				limit;
+	atomic64_t			limit;
 
 	/* Handle for "pids.events" */
 	struct cgroup_file		events_file;
@@ -76,8 +76,8 @@ pids_css_alloc(struct cgroup_subsys_state *parent)
 	if (!pids)
 		return ERR_PTR(-ENOMEM);
 
-	pids->limit = PIDS_MAX;
 	atomic64_set(&pids->counter, 0);
+	atomic64_set(&pids->limit, PIDS_MAX);
 	atomic64_set(&pids->events_limit, 0);
 	return &pids->css;
 }
@@ -149,13 +149,14 @@ static int pids_try_charge(struct pids_cgroup *pids, int num)
 
 	for (p = pids; parent_pids(p); p = parent_pids(p)) {
 		int64_t new = atomic64_add_return(num, &p->counter);
+		int64_t limit = atomic64_read(&p->limit);
 
 		/*
 		 * Since new is capped to the maximum number of pid_t, if
 		 * p->limit is %PIDS_MAX then we know that this test will never
 		 * fail.
 		 */
-		if (new > p->limit)
+		if (new > limit)
 			goto revert;
 	}
 
@@ -280,7 +281,7 @@ set_limit:
 	 * Limit updates don't need to be mutex'd, since it isn't
 	 * critical that any racing fork()s follow the new limit.
 	 */
-	pids->limit = limit;
+	atomic64_set(&pids->limit, limit);
 	return nbytes;
 }
 
@@ -288,7 +289,7 @@ static int pids_max_show(struct seq_file *sf, void *v)
 {
 	struct cgroup_subsys_state *css = seq_css(sf);
 	struct pids_cgroup *pids = css_pids(css);
-	int64_t limit = pids->limit;
+	int64_t limit = atomic64_read(&pids->limit);
 
 	if (limit >= PIDS_MAX)
 		seq_printf(sf, "%s\n", PIDS_MAX_STR);
diff --git a/kernel/cpu.c b/kernel/cpu.c
index bf875e94ac9e..d46f48e94549 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -8,6 +8,7 @@
 #include <linux/init.h>
 #include <linux/notifier.h>
 #include <linux/sched.h>
+#include <linux/sched/smt.h>
 #include <linux/unistd.h>
 #include <linux/cpu.h>
 #include <linux/oom.h>
@@ -356,6 +357,12 @@ void cpu_hotplug_enable(void)
 EXPORT_SYMBOL_GPL(cpu_hotplug_enable);
 #endif	/* CONFIG_HOTPLUG_CPU */
 
+/*
+ * Architectures that need SMT-specific errata handling during SMT hotplug
+ * should override this.
+ */
+void __weak arch_smt_update(void) { }
+
 #ifdef CONFIG_HOTPLUG_SMT
 enum cpuhp_smt_control cpu_smt_control __read_mostly = CPU_SMT_ENABLED;
 EXPORT_SYMBOL_GPL(cpu_smt_control);
@@ -372,6 +379,7 @@ void __init cpu_smt_disable(bool force)
 		pr_info("SMT: Force disabled\n");
 		cpu_smt_control = CPU_SMT_FORCE_DISABLED;
 	} else {
+		pr_info("SMT: disabled\n");
 		cpu_smt_control = CPU_SMT_DISABLED;
 	}
 }
@@ -507,8 +515,7 @@ static int bringup_wait_for_ap(unsigned int cpu)
 	if (WARN_ON_ONCE((!cpu_online(cpu))))
 		return -ECANCELED;
 
-	/* Unpark the stopper thread and the hotplug thread of the target cpu */
-	stop_machine_unpark(cpu);
+	/* Unpark the hotplug thread of the target cpu */
 	kthread_unpark(st->thread);
 
 	/*
@@ -591,6 +598,20 @@ static void undo_cpu_up(unsigned int cpu, struct cpuhp_cpu_state *st)
 	}
 }
 
+static inline bool can_rollback_cpu(struct cpuhp_cpu_state *st)
+{
+	if (IS_ENABLED(CONFIG_HOTPLUG_CPU))
+		return true;
+	/*
+	 * When CPU hotplug is disabled, then taking the CPU down is not
+	 * possible because takedown_cpu() and the architecture and
+	 * subsystem specific mechanisms are not available. So the CPU
+	 * which would be completely unplugged again needs to stay around
+	 * in the current state.
+	 */
+	return st->state <= CPUHP_BRINGUP_CPU;
+}
+
 static int cpuhp_up_callbacks(unsigned int cpu, struct cpuhp_cpu_state *st,
 			      enum cpuhp_state target)
 {
@@ -601,8 +622,10 @@ static int cpuhp_up_callbacks(unsigned int cpu, struct cpuhp_cpu_state *st,
 		st->state++;
 		ret = cpuhp_invoke_callback(cpu, st->state, true, NULL);
 		if (ret) {
-			st->target = prev_state;
-			undo_cpu_up(cpu, st);
+			if (can_rollback_cpu(st)) {
+				st->target = prev_state;
+				undo_cpu_up(cpu, st);
+			}
 			break;
 		}
 	}
@@ -1042,6 +1065,7 @@ out:
 	/* This post dead nonsense must die */
 	if (!ret && hasdied)
 		cpu_notify_nofail(CPU_POST_DEAD, cpu);
+	arch_smt_update();
 	return ret;
 }
 
@@ -1090,8 +1114,8 @@ void notify_cpu_starting(unsigned int cpu)
 
 /*
  * Called from the idle task. Wake up the controlling task which brings the
- * stopper and the hotplug thread of the upcoming CPU up and then delegates
- * the rest of the online bringup to the hotplug thread.
+ * hotplug thread of the upcoming CPU up and then delegates the rest of the
+ * online bringup to the hotplug thread.
  */
 void cpuhp_online_idle(enum cpuhp_state state)
 {
@@ -1101,6 +1125,12 @@ void cpuhp_online_idle(enum cpuhp_state state)
 	if (state != CPUHP_AP_ONLINE_IDLE)
 		return;
 
+	/*
+	 * Unpart the stopper thread before we start the idle loop (and start
+	 * scheduling); this ensures the stopper task is always available.
+	 */
+	stop_machine_unpark(smp_processor_id());
+
 	st->state = CPUHP_AP_ONLINE_IDLE;
 	complete(&st->done);
 }
@@ -1161,6 +1191,7 @@ static int _cpu_up(unsigned int cpu, int tasks_frozen, enum cpuhp_state target)
 	ret = cpuhp_up_callbacks(cpu, st, target);
 out:
 	cpu_hotplug_done();
+	arch_smt_update();
 	return ret;
 }
 
@@ -1970,7 +2001,7 @@ static void cpuhp_online_cpu_device(unsigned int cpu)
 	kobject_uevent(&dev->kobj, KOBJ_ONLINE);
 }
 
-static int cpuhp_smt_disable(enum cpuhp_smt_control ctrlval)
+int cpuhp_smt_disable(enum cpuhp_smt_control ctrlval)
 {
 	int cpu, ret = 0;
 
@@ -2002,7 +2033,7 @@ static int cpuhp_smt_disable(enum cpuhp_smt_control ctrlval)
 	return ret;
 }
 
-static int cpuhp_smt_enable(void)
+int cpuhp_smt_enable(void)
 {
 	int cpu, ret = 0;
 
@@ -2226,3 +2257,46 @@ void idle_notifier_call_chain(unsigned long val)
 	atomic_notifier_call_chain(&idle_notifier, val, NULL);
 }
 EXPORT_SYMBOL_GPL(idle_notifier_call_chain);
+
+/*
+ * These are used for a global "mitigations=" cmdline option for toggling
+ * optional CPU mitigations.
+ */
+enum cpu_mitigations {
+	CPU_MITIGATIONS_OFF,
+	CPU_MITIGATIONS_AUTO,
+	CPU_MITIGATIONS_AUTO_NOSMT,
+};
+
+static enum cpu_mitigations cpu_mitigations __ro_after_init =
+	CPU_MITIGATIONS_AUTO;
+
+static int __init mitigations_parse_cmdline(char *arg)
+{
+	if (!strcmp(arg, "off"))
+		cpu_mitigations = CPU_MITIGATIONS_OFF;
+	else if (!strcmp(arg, "auto"))
+		cpu_mitigations = CPU_MITIGATIONS_AUTO;
+	else if (!strcmp(arg, "auto,nosmt"))
+		cpu_mitigations = CPU_MITIGATIONS_AUTO_NOSMT;
+	else
+		pr_crit("Unsupported mitigations=%s, system may still be vulnerable\n",
+			arg);
+
+	return 0;
+}
+early_param("mitigations", mitigations_parse_cmdline);
+
+/* mitigations=off */
+bool cpu_mitigations_off(void)
+{
+	return cpu_mitigations == CPU_MITIGATIONS_OFF;
+}
+EXPORT_SYMBOL_GPL(cpu_mitigations_off);
+
+/* mitigations=auto,nosmt */
+bool cpu_mitigations_auto_nosmt(void)
+{
+	return cpu_mitigations == CPU_MITIGATIONS_AUTO_NOSMT;
+}
+EXPORT_SYMBOL_GPL(cpu_mitigations_auto_nosmt);
diff --git a/kernel/cred.c b/kernel/cred.c
index 5f264fb5737d..d63a2d861ac2 100644
--- a/kernel/cred.c
+++ b/kernel/cred.c
@@ -146,7 +146,10 @@ void __put_cred(struct cred *cred)
 	BUG_ON(cred == current->cred);
 	BUG_ON(cred == current->real_cred);
 
-	call_rcu(&cred->rcu, put_cred_rcu);
+	if (cred->non_rcu)
+		put_cred_rcu(&cred->rcu);
+	else
+		call_rcu(&cred->rcu, put_cred_rcu);
 }
 EXPORT_SYMBOL(__put_cred);
 
@@ -216,7 +219,7 @@ struct cred *cred_alloc_blank(void)
 	new->magic = CRED_MAGIC;
 #endif
 
-	if (security_cred_alloc_blank(new, GFP_KERNEL) < 0)
+	if (security_cred_alloc_blank(new, GFP_KERNEL_ACCOUNT) < 0)
 		goto error;
 
 	return new;
@@ -257,6 +260,7 @@ struct cred *prepare_creds(void)
 	old = task->cred;
 	memcpy(new, old, sizeof(struct cred));
 
+	new->non_rcu = 0;
 	atomic_set(&new->usage, 1);
 	set_cred_subscribers(new, 0);
 	get_group_info(new->group_info);
@@ -274,7 +278,7 @@ struct cred *prepare_creds(void)
 	new->security = NULL;
 #endif
 
-	if (security_prepare_creds(new, old, GFP_KERNEL) < 0)
+	if (security_prepare_creds(new, old, GFP_KERNEL_ACCOUNT) < 0)
 		goto error;
 	validate_creds(new);
 	return new;
@@ -447,6 +451,15 @@ int commit_creds(struct cred *new)
 		if (task->mm)
 			set_dumpable(task->mm, suid_dumpable);
 		task->pdeath_signal = 0;
+		/*
+		 * If a task drops privileges and becomes nondumpable,
+		 * the dumpability change must become visible before
+		 * the credential change; otherwise, a __ptrace_may_access()
+		 * racing with this change may be able to attach to a task it
+		 * shouldn't be able to attach to (as if the task had dropped
+		 * privileges without becoming nondumpable).
+		 * Pairs with a read barrier in __ptrace_may_access().
+		 */
 		smp_wmb();
 	}
 
@@ -527,7 +540,19 @@ const struct cred *override_creds(const struct cred *new)
 
 	validate_creds(old);
 	validate_creds(new);
-	get_cred(new);
+
+	/*
+	 * NOTE! This uses 'get_new_cred()' rather than 'get_cred()'.
+	 *
+	 * That means that we do not clear the 'non_rcu' flag, since
+	 * we are only installing the cred into the thread-synchronous
+	 * '->cred' pointer, not the '->real_cred' pointer that is
+	 * visible to other threads under RCU.
+	 *
+	 * Also note that we did validate_creds() manually, not depending
+	 * on the validation in 'get_cred()'.
+	 */
+	get_new_cred((struct cred *)new);
 	alter_cred_subscribers(new, 1);
 	rcu_assign_pointer(current->cred, new);
 	alter_cred_subscribers(old, -1);
@@ -610,6 +635,7 @@ struct cred *prepare_kernel_cred(struct task_struct *daemon)
 	validate_creds(old);
 
 	*new = *old;
+	new->non_rcu = 0;
 	atomic_set(&new->usage, 1);
 	set_cred_subscribers(new, 0);
 	get_uid(new->user);
@@ -627,7 +653,7 @@ struct cred *prepare_kernel_cred(struct task_struct *daemon)
 #ifdef CONFIG_SECURITY
 	new->security = NULL;
 #endif
-	if (security_prepare_creds(new, old, GFP_KERNEL) < 0)
+	if (security_prepare_creds(new, old, GFP_KERNEL_ACCOUNT) < 0)
 		goto error;
 
 	put_cred(old);
diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index 5a58421d7e2d..a52a6da8c3d0 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -2632,7 +2632,7 @@ static int kdb_per_cpu(int argc, const char **argv)
 		diag = kdbgetularg(argv[3], &whichcpu);
 		if (diag)
 			return diag;
-		if (!cpu_online(whichcpu)) {
+		if (whichcpu >= nr_cpu_ids || !cpu_online(whichcpu)) {
 			kdb_printf("cpu %ld is not online\n", whichcpu);
 			return KDB_BADCPUNUM;
 		}
diff --git a/kernel/elfcore.c b/kernel/elfcore.c
index e556751d15d9..a2b29b9bdfcb 100644
--- a/kernel/elfcore.c
+++ b/kernel/elfcore.c
@@ -2,6 +2,7 @@
 #include <linux/fs.h>
 #include <linux/mm.h>
 #include <linux/binfmts.h>
+#include <linux/elfcore.h>
 
 Elf_Half __weak elf_core_extra_phdrs(void)
 {
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 5cbb2eda80b5..97b90faceb97 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -4624,6 +4624,9 @@ static int perf_event_period(struct perf_event *event, u64 __user *arg)
 	if (perf_event_check_period(event, value))
 		return -EINVAL;
 
+	if (!event->attr.freq && (value & (1ULL << 63)))
+		return -EINVAL;
+
 	event_function_call(event, __perf_event_period, &value);
 
 	return 0;
@@ -5300,7 +5303,15 @@ accounting:
 	 */
 	user_lock_limit *= num_online_cpus();
 
-	user_locked = atomic_long_read(&user->locked_vm) + user_extra;
+	user_locked = atomic_long_read(&user->locked_vm);
+
+	/*
+	 * sysctl_perf_event_mlock may have changed, so that
+	 *     user->locked_vm > user_lock_limit
+	 */
+	if (user_locked > user_lock_limit)
+		user_locked = user_lock_limit;
+	user_locked += user_extra;
 
 	if (user_locked > user_lock_limit)
 		extra = user_locked - user_lock_limit;
@@ -5492,7 +5503,7 @@ static void perf_sample_regs_user(struct perf_regs *regs_user,
 	if (user_mode(regs)) {
 		regs_user->abi = perf_reg_abi(current);
 		regs_user->regs = regs;
-	} else if (current->mm) {
+	} else if (!(current->flags & PF_KTHREAD)) {
 		perf_get_regs_user(regs_user, regs, regs_user_copy);
 	} else {
 		regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE;
@@ -6616,6 +6627,7 @@ static void perf_event_mmap_output(struct perf_event *event,
 	struct perf_output_handle handle;
 	struct perf_sample_data sample;
 	int size = mmap_event->event_id.header.size;
+	u32 type = mmap_event->event_id.header.type;
 	int ret;
 
 	if (!perf_event_mmap_match(event, data))
@@ -6659,6 +6671,7 @@ static void perf_event_mmap_output(struct perf_event *event,
 	perf_output_end(&handle);
 out:
 	mmap_event->event_id.header.size = size;
+	mmap_event->event_id.header.type = type;
 }
 
 static void perf_event_mmap_event(struct perf_mmap_event *mmap_event)
@@ -10128,7 +10141,7 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu,
 		goto err_unlock;
 	}
 
-	perf_install_in_context(ctx, event, cpu);
+	perf_install_in_context(ctx, event, event->cpu);
 	perf_unpin_context(ctx);
 	mutex_unlock(&ctx->mutex);
 
diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c
index 99becab2c1ce..8e8b903b7613 100644
--- a/kernel/events/ring_buffer.c
+++ b/kernel/events/ring_buffer.c
@@ -49,14 +49,30 @@ static void perf_output_put_handle(struct perf_output_handle *handle)
 	unsigned long head;
 
 again:
+	/*
+	 * In order to avoid publishing a head value that goes backwards,
+	 * we must ensure the load of @rb->head happens after we've
+	 * incremented @rb->nest.
+	 *
+	 * Otherwise we can observe a @rb->head value before one published
+	 * by an IRQ/NMI happening between the load and the increment.
+	 */
+	barrier();
 	head = local_read(&rb->head);
 
 	/*
-	 * IRQ/NMI can happen here, which means we can miss a head update.
+	 * IRQ/NMI can happen here and advance @rb->head, causing our
+	 * load above to be stale.
 	 */
 
-	if (!local_dec_and_test(&rb->nest))
+	/*
+	 * If this isn't the outermost nesting, we don't have to update
+	 * @rb->user_page->data_head.
+	 */
+	if (local_read(&rb->nest) > 1) {
+		local_dec(&rb->nest);
 		goto out;
+	}
 
 	/*
 	 * Since the mmap() consumer (userspace) can run on a different CPU:
@@ -88,9 +104,18 @@ again:
 	rb->user_page->data_head = head;
 
 	/*
-	 * Now check if we missed an update -- rely on previous implied
-	 * compiler barriers to force a re-read.
+	 * We must publish the head before decrementing the nest count,
+	 * otherwise an IRQ/NMI can publish a more recent head value and our
+	 * write will (temporarily) publish a stale value.
+	 */
+	barrier();
+	local_set(&rb->nest, 0);
+
+	/*
+	 * Ensure we decrement @rb->nest before we validate the @rb->head.
+	 * Otherwise we cannot be sure we caught the 'last' nested update.
 	 */
+	barrier();
 	if (unlikely(head != local_read(&rb->head))) {
 		local_inc(&rb->nest);
 		goto again;
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index fbfab5722254..8ddd29476c0d 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -1846,7 +1846,7 @@ static void handle_trampoline(struct pt_regs *regs)
 
  sigill:
 	uprobe_warn(current, "handle uretprobe, sending SIGILL.");
-	force_sig_info(SIGILL, SEND_SIG_FORCED, current);
+	force_sig(SIGILL, current);
 
 }
 
@@ -1962,7 +1962,7 @@ static void handle_singlestep(struct uprobe_task *utask, struct pt_regs *regs)
 
 	if (unlikely(err)) {
 		uprobe_warn(current, "execute the probed insn, sending SIGILL.");
-		force_sig_info(SIGILL, SEND_SIG_FORCED, current);
+		force_sig(SIGILL, current);
 	}
 }
 
diff --git a/kernel/fork.c b/kernel/fork.c
index e92b06351dec..288504431a53 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -389,7 +389,7 @@ void __put_task_struct(struct task_struct *tsk)
 	WARN_ON(tsk == current);
 
 	cgroup_free(tsk);
-	task_numa_free(tsk);
+	task_numa_free(tsk, true);
 	security_task_free(tsk);
 	exit_creds(tsk);
 	delayacct_tsk_free(tsk);
@@ -2356,7 +2356,7 @@ int sysctl_max_threads(struct ctl_table *table, int write,
 	struct ctl_table t;
 	int ret;
 	int threads = max_threads;
-	int min = MIN_THREADS;
+	int min = 1;
 	int max = MAX_THREADS;
 
 	t = *table;
@@ -2368,7 +2368,7 @@ int sysctl_max_threads(struct ctl_table *table, int write,
 	if (ret || !write)
 		return ret;
 
-	set_max_threads(threads);
+	max_threads = threads;
 
 	return 0;
 }
diff --git a/kernel/futex.c b/kernel/futex.c
index 2e766ffff2cb..7123d9cab456 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -390,9 +390,9 @@ static inline int hb_waiters_pending(struct futex_hash_bucket *hb)
  */
 static struct futex_hash_bucket *hash_futex(union futex_key *key)
 {
-	u32 hash = jhash2((u32*)&key->both.word,
-			  (sizeof(key->both.word)+sizeof(key->both.ptr))/4,
+	u32 hash = jhash2((u32 *)key, offsetof(typeof(*key), both.offset) / 4,
 			  key->both.offset);
+
 	return &futex_queues[hash & (futex_hashsize - 1)];
 }
 
@@ -434,7 +434,7 @@ static void get_futex_key_refs(union futex_key *key)
 
 	switch (key->both.offset & (FUT_OFF_INODE|FUT_OFF_MMSHARED)) {
 	case FUT_OFF_INODE:
-		ihold(key->shared.inode); /* implies smp_mb(); (B) */
+		smp_mb();		/* explicit smp_mb(); (B) */
 		break;
 	case FUT_OFF_MMSHARED:
 		futex_get_mm(key); /* implies smp_mb(); (B) */
@@ -468,7 +468,6 @@ static void drop_futex_key_refs(union futex_key *key)
 
 	switch (key->both.offset & (FUT_OFF_INODE|FUT_OFF_MMSHARED)) {
 	case FUT_OFF_INODE:
-		iput(key->shared.inode);
 		break;
 	case FUT_OFF_MMSHARED:
 		mmdrop(key->private.mm);
@@ -476,6 +475,46 @@ static void drop_futex_key_refs(union futex_key *key)
 	}
 }
 
+/*
+ * Generate a machine wide unique identifier for this inode.
+ *
+ * This relies on u64 not wrapping in the life-time of the machine; which with
+ * 1ns resolution means almost 585 years.
+ *
+ * This further relies on the fact that a well formed program will not unmap
+ * the file while it has a (shared) futex waiting on it. This mapping will have
+ * a file reference which pins the mount and inode.
+ *
+ * If for some reason an inode gets evicted and read back in again, it will get
+ * a new sequence number and will _NOT_ match, even though it is the exact same
+ * file.
+ *
+ * It is important that match_futex() will never have a false-positive, esp.
+ * for PI futexes that can mess up the state. The above argues that false-negatives
+ * are only possible for malformed programs.
+ */
+static u64 get_inode_sequence_number(struct inode *inode)
+{
+	static atomic64_t i_seq;
+	u64 old;
+
+	/* Does the inode already have a sequence number? */
+	old = atomic64_read(&inode->i_sequence);
+	if (likely(old))
+		return old;
+
+	for (;;) {
+		u64 new = atomic64_add_return(1, &i_seq);
+		if (WARN_ON_ONCE(!new))
+			continue;
+
+		old = atomic64_cmpxchg_relaxed(&inode->i_sequence, 0, new);
+		if (old)
+			return old;
+		return new;
+	}
+}
+
 /**
  * get_futex_key() - Get parameters which are the keys for a futex
  * @uaddr:	virtual address of the futex
@@ -488,9 +527,15 @@ static void drop_futex_key_refs(union futex_key *key)
  *
  * The key words are stored in *key on success.
  *
- * For shared mappings, it's (page->index, file_inode(vma->vm_file),
- * offset_within_page).  For private mappings, it's (uaddr, current->mm).
- * We can usually work out the index without swapping in the page.
+ * For shared mappings (when @fshared), the key is:
+ *   ( inode->i_sequence, page->index, offset_within_page )
+ * [ also see get_inode_sequence_number() ]
+ *
+ * For private mappings (or when !@fshared), the key is:
+ *   ( current->mm, address, 0 )
+ *
+ * This allows (cross process, where applicable) identification of the futex
+ * without keeping the page pinned for the duration of the FUTEX_WAIT.
  *
  * lock_page() might sleep, the caller should not hold a spinlock.
  */
@@ -630,8 +675,6 @@ again:
 		key->private.mm = mm;
 		key->private.address = address;
 
-		get_futex_key_refs(key); /* implies smp_mb(); (B) */
-
 	} else {
 		struct inode *inode;
 
@@ -663,40 +706,14 @@ again:
 			goto again;
 		}
 
-		/*
-		 * Take a reference unless it is about to be freed. Previously
-		 * this reference was taken by ihold under the page lock
-		 * pinning the inode in place so i_lock was unnecessary. The
-		 * only way for this check to fail is if the inode was
-		 * truncated in parallel which is almost certainly an
-		 * application bug. In such a case, just retry.
-		 *
-		 * We are not calling into get_futex_key_refs() in file-backed
-		 * cases, therefore a successful atomic_inc return below will
-		 * guarantee that get_futex_key() will still imply smp_mb(); (B).
-		 */
-		if (!atomic_inc_not_zero(&inode->i_count)) {
-			rcu_read_unlock();
-			put_page(page);
-
-			goto again;
-		}
-
-		/* Should be impossible but lets be paranoid for now */
-		if (WARN_ON_ONCE(inode->i_mapping != mapping)) {
-			err = -EFAULT;
-			rcu_read_unlock();
-			iput(inode);
-
-			goto out;
-		}
-
 		key->both.offset |= FUT_OFF_INODE; /* inode-based key */
-		key->shared.inode = inode;
+		key->shared.i_seq = get_inode_sequence_number(inode);
 		key->shared.pgoff = basepage_index(tail);
 		rcu_read_unlock();
 	}
 
+	get_futex_key_refs(key); /* implies smp_mb(); (B) */
+
 out:
 	put_page(page);
 	return err;
diff --git a/kernel/hung_task.c b/kernel/hung_task.c
index fd781a468f32..fb00cf30abd1 100644
--- a/kernel/hung_task.c
+++ b/kernel/hung_task.c
@@ -15,6 +15,7 @@
 #include <linux/lockdep.h>
 #include <linux/export.h>
 #include <linux/sysctl.h>
+#include <linux/suspend.h>
 #include <linux/utsname.h>
 #include <trace/events/sched.h>
 
@@ -221,6 +222,28 @@ void reset_hung_task_detector(void)
 }
 EXPORT_SYMBOL_GPL(reset_hung_task_detector);
 
+static bool hung_detector_suspended;
+
+static int hungtask_pm_notify(struct notifier_block *self,
+			      unsigned long action, void *hcpu)
+{
+	switch (action) {
+	case PM_SUSPEND_PREPARE:
+	case PM_HIBERNATION_PREPARE:
+	case PM_RESTORE_PREPARE:
+		hung_detector_suspended = true;
+		break;
+	case PM_POST_SUSPEND:
+	case PM_POST_HIBERNATION:
+	case PM_POST_RESTORE:
+		hung_detector_suspended = false;
+		break;
+	default:
+		break;
+	}
+	return NOTIFY_OK;
+}
+
 /*
  * kthread which checks for tasks stuck in D state
  */
@@ -235,7 +258,8 @@ static int watchdog(void *dummy)
 		long t = hung_timeout_jiffies(hung_last_checked, timeout);
 
 		if (t <= 0) {
-			if (!atomic_xchg(&reset_hung_task, 0))
+			if (!atomic_xchg(&reset_hung_task, 0) &&
+			    !hung_detector_suspended)
 				check_hung_uninterruptible_tasks(timeout);
 			hung_last_checked = jiffies;
 			continue;
@@ -249,6 +273,10 @@ static int watchdog(void *dummy)
 static int __init hung_task_init(void)
 {
 	atomic_notifier_chain_register(&panic_notifier_list, &panic_block);
+
+	/* Disable hung task detector on suspend */
+	pm_notifier(hungtask_pm_notify, 0);
+
 	watchdog_task = kthread_run(watchdog, NULL, "khungtaskd");
 
 	return 0;
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index f30110e1b8c9..9f13667ccb9c 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -729,7 +729,11 @@ void handle_percpu_irq(struct irq_desc *desc)
 {
 	struct irq_chip *chip = irq_desc_get_chip(desc);
 
-	kstat_incr_irqs_this_cpu(desc);
+	/*
+	 * PER CPU interrupts are not serialized. Do not touch
+	 * desc->tot_count.
+	 */
+	__kstat_incr_irqs_this_cpu(desc);
 
 	if (chip->irq_ack)
 		chip->irq_ack(&desc->irq_data);
@@ -758,7 +762,11 @@ void handle_percpu_devid_irq(struct irq_desc *desc)
 	unsigned int irq = irq_desc_get_irq(desc);
 	irqreturn_t res;
 
-	kstat_incr_irqs_this_cpu(desc);
+	/*
+	 * PER CPU interrupts are not serialized. Do not touch
+	 * desc->tot_count.
+	 */
+	__kstat_incr_irqs_this_cpu(desc);
 
 	if (chip->irq_ack)
 		chip->irq_ack(&desc->irq_data);
@@ -1134,6 +1142,10 @@ int irq_chip_set_vcpu_affinity_parent(struct irq_data *data, void *vcpu_info)
 int irq_chip_set_wake_parent(struct irq_data *data, unsigned int on)
 {
 	data = data->parent_data;
+
+	if (data->chip->flags & IRQCHIP_SKIP_SET_WAKE)
+		return 0;
+
 	if (data->chip->irq_set_wake)
 		return data->chip->irq_set_wake(data, on);
 
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index bc226e783bd2..22e3f29a30d8 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -199,12 +199,18 @@ static inline bool irqd_has_set(struct irq_data *d, unsigned int mask)
 
 #undef __irqd_to_state
 
-static inline void kstat_incr_irqs_this_cpu(struct irq_desc *desc)
+static inline void __kstat_incr_irqs_this_cpu(struct irq_desc *desc)
 {
 	__this_cpu_inc(*desc->kstat_irqs);
 	__this_cpu_inc(kstat.irqs_sum);
 }
 
+static inline void kstat_incr_irqs_this_cpu(struct irq_desc *desc)
+{
+	__kstat_incr_irqs_this_cpu(desc);
+	desc->tot_count++;
+}
+
 static inline int irq_desc_get_node(struct irq_desc *desc)
 {
 	return irq_common_data_get_node(&desc->irq_common_data);
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index 77977f55dff7..8847f277a14f 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -109,6 +109,7 @@ static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node,
 	desc->depth = 1;
 	desc->irq_count = 0;
 	desc->irqs_unhandled = 0;
+	desc->tot_count = 0;
 	desc->name = NULL;
 	desc->owner = owner;
 	for_each_possible_cpu(cpu)
@@ -266,6 +267,18 @@ static void irq_sysfs_add(int irq, struct irq_desc *desc)
 	}
 }
 
+static void irq_sysfs_del(struct irq_desc *desc)
+{
+	/*
+	 * If irq_sysfs_init() has not yet been invoked (early boot), then
+	 * irq_kobj_base is NULL and the descriptor was never added.
+	 * kobject_del() complains about a object with no parent, so make
+	 * it conditional.
+	 */
+	if (irq_kobj_base)
+		kobject_del(&desc->kobj);
+}
+
 static int __init irq_sysfs_init(void)
 {
 	struct irq_desc *desc;
@@ -296,6 +309,7 @@ static struct kobj_type irq_kobj_type = {
 };
 
 static void irq_sysfs_add(int irq, struct irq_desc *desc) {}
+static void irq_sysfs_del(struct irq_desc *desc) {}
 
 #endif /* CONFIG_SYSFS */
 
@@ -405,7 +419,7 @@ static void free_desc(unsigned int irq)
 	 * The sysfs entry must be serialized against a concurrent
 	 * irq_sysfs_init() as well.
 	 */
-	kobject_del(&desc->kobj);
+	irq_sysfs_del(desc);
 	delete_irq_desc(irq);
 
 	/*
@@ -880,11 +894,15 @@ unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
 unsigned int kstat_irqs(unsigned int irq)
 {
 	struct irq_desc *desc = irq_to_desc(irq);
-	int cpu;
 	unsigned int sum = 0;
+	int cpu;
 
 	if (!desc || !desc->kstat_irqs)
 		return 0;
+	if (!irq_settings_is_per_cpu_devid(desc) &&
+	    !irq_settings_is_per_cpu(desc))
+	    return desc->tot_count;
+
 	for_each_possible_cpu(cpu)
 		sum += *per_cpu_ptr(desc->kstat_irqs, cpu);
 	return sum;
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index cf94460504bb..b2fc2a581b86 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -233,7 +233,11 @@ int irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask,
 
 	if (desc->affinity_notify) {
 		kref_get(&desc->affinity_notify->kref);
-		schedule_work(&desc->affinity_notify->work);
+		if (!schedule_work(&desc->affinity_notify->work)) {
+			/* Work was already scheduled, drop our extra ref */
+			kref_put(&desc->affinity_notify->kref,
+				 desc->affinity_notify->release);
+		}
 	}
 	irqd_set(data, IRQD_AFFINITY_SET);
 
@@ -332,8 +336,13 @@ irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)
 	desc->affinity_notify = notify;
 	raw_spin_unlock_irqrestore(&desc->lock, flags);
 
-	if (old_notify)
+	if (old_notify) {
+		if (cancel_work_sync(&old_notify->work)) {
+			/* Pending work had a ref, put that one too */
+			kref_put(&old_notify->kref, old_notify->release);
+		}
 		kref_put(&old_notify->kref, old_notify->release);
+	}
 
 	return 0;
 }
diff --git a/kernel/irq/resend.c b/kernel/irq/resend.c
index b86886beee4f..867fb0ed4aa6 100644
--- a/kernel/irq/resend.c
+++ b/kernel/irq/resend.c
@@ -37,6 +37,8 @@ static void resend_irqs(unsigned long arg)
 		irq = find_first_bit(irqs_resend, nr_irqs);
 		clear_bit(irq, irqs_resend);
 		desc = irq_to_desc(irq);
+		if (!desc)
+			continue;
 		local_irq_disable();
 		desc->handle_irq(desc);
 		local_irq_enable();
diff --git a/kernel/kmod.c b/kernel/kmod.c
index 0277d1216f80..e4e5e98002fe 100644
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -119,7 +119,7 @@ out:
  * invoke it.
  *
  * If module auto-loading support is disabled then this function
- * becomes a no-operation.
+ * simply returns -ENOENT.
  */
 int __request_module(bool wait, const char *fmt, ...)
 {
@@ -140,7 +140,7 @@ int __request_module(bool wait, const char *fmt, ...)
 	WARN_ON_ONCE(wait && current_is_async());
 
 	if (!modprobe_path[0])
-		return 0;
+		return -ENOENT;
 
 	va_start(args, fmt);
 	ret = vsnprintf(module_name, MODULE_NAME_LEN, fmt, args);
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index f580352cc6e5..1b75fb8c7735 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -514,8 +514,14 @@ static void do_free_cleaned_kprobes(void)
 	struct optimized_kprobe *op, *tmp;
 
 	list_for_each_entry_safe(op, tmp, &freeing_list, list) {
-		BUG_ON(!kprobe_unused(&op->kp));
 		list_del_init(&op->list);
+		if (WARN_ON_ONCE(!kprobe_unused(&op->kp))) {
+			/*
+			 * This must not happen, but if there is a kprobe
+			 * still in use, keep it on kprobes hash list.
+			 */
+			continue;
+		}
 		free_aggr_kprobe(&op->kp);
 	}
 }
@@ -668,7 +674,6 @@ static void unoptimize_kprobe(struct kprobe *p, bool force)
 static int reuse_unused_kprobe(struct kprobe *ap)
 {
 	struct optimized_kprobe *op;
-	int ret;
 
 	BUG_ON(!kprobe_unused(ap));
 	/*
@@ -682,9 +687,8 @@ static int reuse_unused_kprobe(struct kprobe *ap)
 	/* Enable the probe again */
 	ap->flags &= ~KPROBE_FLAG_DISABLED;
 	/* Optimize it again (remove from op->list) */
-	ret = kprobe_optready(ap);
-	if (ret)
-		return ret;
+	if (!kprobe_optready(ap))
+		return -EINVAL;
 
 	optimize_kprobe(ap);
 	return 0;
@@ -1456,7 +1460,8 @@ static int check_kprobe_address_safe(struct kprobe *p,
 	/* Ensure it is not in reserved area nor out of text */
 	if (!kernel_text_address((unsigned long) p->addr) ||
 	    within_kprobe_blacklist((unsigned long) p->addr) ||
-	    jump_label_text_reserved(p->addr, p->addr)) {
+	    jump_label_text_reserved(p->addr, p->addr) ||
+	    find_bug((unsigned long)p->addr)) {
 		ret = -EINVAL;
 		goto out;
 	}
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index d5b779d7e79f..9f56e3fac795 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -1241,9 +1241,11 @@ unsigned long lockdep_count_forward_deps(struct lock_class *class)
 	this.class = class;
 
 	raw_local_irq_save(flags);
+	current->lockdep_recursion = 1;
 	arch_spin_lock(&lockdep_lock);
 	ret = __lockdep_count_forward_deps(&this);
 	arch_spin_unlock(&lockdep_lock);
+	current->lockdep_recursion = 0;
 	raw_local_irq_restore(flags);
 
 	return ret;
@@ -1268,9 +1270,11 @@ unsigned long lockdep_count_backward_deps(struct lock_class *class)
 	this.class = class;
 
 	raw_local_irq_save(flags);
+	current->lockdep_recursion = 1;
 	arch_spin_lock(&lockdep_lock);
 	ret = __lockdep_count_backward_deps(&this);
 	arch_spin_unlock(&lockdep_lock);
+	current->lockdep_recursion = 0;
 	raw_local_irq_restore(flags);
 
 	return ret;
@@ -3260,17 +3264,17 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
 	if (depth) {
 		hlock = curr->held_locks + depth - 1;
 		if (hlock->class_idx == class_idx && nest_lock) {
-			if (hlock->references) {
-				/*
-				 * Check: unsigned int references:12, overflow.
-				 */
-				if (DEBUG_LOCKS_WARN_ON(hlock->references == (1 << 12)-1))
-					return 0;
+			if (!references)
+				references++;
 
+			if (!hlock->references)
 				hlock->references++;
-			} else {
-				hlock->references = 2;
-			}
+
+			hlock->references += references;
+
+			/* Overflow */
+			if (DEBUG_LOCKS_WARN_ON(hlock->references < references))
+				return 0;
 
 			return 1;
 		}
diff --git a/kernel/locking/lockdep_proc.c b/kernel/locking/lockdep_proc.c
index a0f61effad25..75d80809c48c 100644
--- a/kernel/locking/lockdep_proc.c
+++ b/kernel/locking/lockdep_proc.c
@@ -219,7 +219,6 @@ static void lockdep_stats_debug_show(struct seq_file *m)
 
 static int lockdep_stats_show(struct seq_file *m, void *v)
 {
-	struct lock_class *class;
 	unsigned long nr_unused = 0, nr_uncategorized = 0,
 		      nr_irq_safe = 0, nr_irq_unsafe = 0,
 		      nr_softirq_safe = 0, nr_softirq_unsafe = 0,
@@ -229,6 +228,9 @@ static int lockdep_stats_show(struct seq_file *m, void *v)
 		      nr_hardirq_read_safe = 0, nr_hardirq_read_unsafe = 0,
 		      sum_forward_deps = 0;
 
+#ifdef CONFIG_PROVE_LOCKING
+	struct lock_class *class;
+
 	list_for_each_entry(class, &all_lock_classes, lock_entry) {
 
 		if (class->usage_mask == 0)
@@ -260,13 +262,13 @@ static int lockdep_stats_show(struct seq_file *m, void *v)
 		if (class->usage_mask & LOCKF_ENABLED_HARDIRQ_READ)
 			nr_hardirq_read_unsafe++;
 
-#ifdef CONFIG_PROVE_LOCKING
 		sum_forward_deps += lockdep_count_forward_deps(class);
-#endif
 	}
 #ifdef CONFIG_DEBUG_LOCKDEP
 	DEBUG_LOCKS_WARN_ON(debug_atomic_read(nr_unused_locks) != nr_unused);
 #endif
+
+#endif
 	seq_printf(m, " lock-classes:                  %11lu [max: %lu]\n",
 			nr_lock_classes, MAX_LOCKDEP_KEYS);
 	seq_printf(m, " direct dependencies:           %11lu [max: %lu]\n",
diff --git a/kernel/locking/locktorture.c b/kernel/locking/locktorture.c
index babc67cfed69..b0e41c312c15 100644
--- a/kernel/locking/locktorture.c
+++ b/kernel/locking/locktorture.c
@@ -649,10 +649,10 @@ static void __torture_print_stats(char *page,
 		if (statp[i].n_lock_fail)
 			fail = true;
 		sum += statp[i].n_lock_acquired;
-		if (max < statp[i].n_lock_fail)
-			max = statp[i].n_lock_fail;
-		if (min > statp[i].n_lock_fail)
-			min = statp[i].n_lock_fail;
+		if (max < statp[i].n_lock_acquired)
+			max = statp[i].n_lock_acquired;
+		if (min > statp[i].n_lock_acquired)
+			min = statp[i].n_lock_acquired;
 	}
 	page += sprintf(page,
 			"%s:  Total: %lld  Max/Min: %ld/%ld %s  Fail: %d %s\n",
diff --git a/kernel/locking/rwsem-xadd.c b/kernel/locking/rwsem-xadd.c
index be06c45cbe4f..0cdbb636e316 100644
--- a/kernel/locking/rwsem-xadd.c
+++ b/kernel/locking/rwsem-xadd.c
@@ -127,6 +127,7 @@ static void __rwsem_mark_wake(struct rw_semaphore *sem,
 {
 	struct rwsem_waiter *waiter, *tmp;
 	long oldcount, woken = 0, adjustment = 0;
+	struct list_head wlist;
 
 	/*
 	 * Take a peek at the queue head waiter such that we can determine
@@ -185,18 +186,42 @@ static void __rwsem_mark_wake(struct rw_semaphore *sem,
 	 * of the queue. We know that woken will be at least 1 as we accounted
 	 * for above. Note we increment the 'active part' of the count by the
 	 * number of readers before waking any processes up.
+	 *
+	 * We have to do wakeup in 2 passes to prevent the possibility that
+	 * the reader count may be decremented before it is incremented. It
+	 * is because the to-be-woken waiter may not have slept yet. So it
+	 * may see waiter->task got cleared, finish its critical section and
+	 * do an unlock before the reader count increment.
+	 *
+	 * 1) Collect the read-waiters in a separate list, count them and
+	 *    fully increment the reader count in rwsem.
+	 * 2) For each waiters in the new list, clear waiter->task and
+	 *    put them into wake_q to be woken up later.
 	 */
-	list_for_each_entry_safe(waiter, tmp, &sem->wait_list, list) {
-		struct task_struct *tsk;
-
+	list_for_each_entry(waiter, &sem->wait_list, list) {
 		if (waiter->type == RWSEM_WAITING_FOR_WRITE)
 			break;
 
 		woken++;
-		tsk = waiter->task;
+	}
+	list_cut_before(&wlist, &sem->wait_list, &waiter->list);
+
+	adjustment = woken * RWSEM_ACTIVE_READ_BIAS - adjustment;
+	if (list_empty(&sem->wait_list)) {
+		/* hit end of list above */
+		adjustment -= RWSEM_WAITING_BIAS;
+	}
+
+	if (adjustment)
+		atomic_long_add(adjustment, &sem->count);
+
+	/* 2nd pass */
+	list_for_each_entry_safe(waiter, tmp, &wlist, list) {
+		struct task_struct *tsk;
 
+		tsk = waiter->task;
 		get_task_struct(tsk);
-		list_del(&waiter->list);
+
 		/*
 		 * Ensure calling get_task_struct() before setting the reader
 		 * waiter to nil such that rwsem_down_read_failed() cannot
@@ -212,15 +237,6 @@ static void __rwsem_mark_wake(struct rw_semaphore *sem,
 		/* wake_q_add() already take the task ref */
 		put_task_struct(tsk);
 	}
-
-	adjustment = woken * RWSEM_ACTIVE_READ_BIAS - adjustment;
-	if (list_empty(&sem->wait_list)) {
-		/* hit end of list above */
-		adjustment -= RWSEM_WAITING_BIAS;
-	}
-
-	if (adjustment)
-		atomic_long_add(adjustment, &sem->count);
 }
 
 /*
diff --git a/kernel/locking/spinlock_debug.c b/kernel/locking/spinlock_debug.c
index 9aa0fccd5d43..03595c29c566 100644
--- a/kernel/locking/spinlock_debug.c
+++ b/kernel/locking/spinlock_debug.c
@@ -51,19 +51,19 @@ EXPORT_SYMBOL(__rwlock_init);
 
 static void spin_dump(raw_spinlock_t *lock, const char *msg)
 {
-	struct task_struct *owner = NULL;
+	struct task_struct *owner = READ_ONCE(lock->owner);
 
-	if (lock->owner && lock->owner != SPINLOCK_OWNER_INIT)
-		owner = lock->owner;
+	if (owner == SPINLOCK_OWNER_INIT)
+		owner = NULL;
 	printk(KERN_EMERG "BUG: spinlock %s on CPU#%d, %s/%d\n",
 		msg, raw_smp_processor_id(),
 		current->comm, task_pid_nr(current));
 	printk(KERN_EMERG " lock: %pS, .magic: %08x, .owner: %s/%d, "
 			".owner_cpu: %d\n",
-		lock, lock->magic,
+		lock, READ_ONCE(lock->magic),
 		owner ? owner->comm : "<none>",
 		owner ? task_pid_nr(owner) : -1,
-		lock->owner_cpu);
+		READ_ONCE(lock->owner_cpu));
 	dump_stack();
 }
 
@@ -80,16 +80,16 @@ static void spin_bug(raw_spinlock_t *lock, const char *msg)
 static inline void
 debug_spin_lock_before(raw_spinlock_t *lock)
 {
-	SPIN_BUG_ON(lock->magic != SPINLOCK_MAGIC, lock, "bad magic");
-	SPIN_BUG_ON(lock->owner == current, lock, "recursion");
-	SPIN_BUG_ON(lock->owner_cpu == raw_smp_processor_id(),
+	SPIN_BUG_ON(READ_ONCE(lock->magic) != SPINLOCK_MAGIC, lock, "bad magic");
+	SPIN_BUG_ON(READ_ONCE(lock->owner) == current, lock, "recursion");
+	SPIN_BUG_ON(READ_ONCE(lock->owner_cpu) == raw_smp_processor_id(),
 							lock, "cpu recursion");
 }
 
 static inline void debug_spin_lock_after(raw_spinlock_t *lock)
 {
-	lock->owner_cpu = raw_smp_processor_id();
-	lock->owner = current;
+	WRITE_ONCE(lock->owner_cpu, raw_smp_processor_id());
+	WRITE_ONCE(lock->owner, current);
 }
 
 static inline void debug_spin_unlock(raw_spinlock_t *lock)
@@ -99,8 +99,8 @@ static inline void debug_spin_unlock(raw_spinlock_t *lock)
 	SPIN_BUG_ON(lock->owner != current, lock, "wrong owner");
 	SPIN_BUG_ON(lock->owner_cpu != raw_smp_processor_id(),
 							lock, "wrong CPU");
-	lock->owner = SPINLOCK_OWNER_INIT;
-	lock->owner_cpu = -1;
+	WRITE_ONCE(lock->owner, SPINLOCK_OWNER_INIT);
+	WRITE_ONCE(lock->owner_cpu, -1);
 }
 
 /*
@@ -183,8 +183,8 @@ static inline void debug_write_lock_before(rwlock_t *lock)
 
 static inline void debug_write_lock_after(rwlock_t *lock)
 {
-	lock->owner_cpu = raw_smp_processor_id();
-	lock->owner = current;
+	WRITE_ONCE(lock->owner_cpu, raw_smp_processor_id());
+	WRITE_ONCE(lock->owner, current);
 }
 
 static inline void debug_write_unlock(rwlock_t *lock)
@@ -193,8 +193,8 @@ static inline void debug_write_unlock(rwlock_t *lock)
 	RWLOCK_BUG_ON(lock->owner != current, lock, "wrong owner");
 	RWLOCK_BUG_ON(lock->owner_cpu != raw_smp_processor_id(),
 							lock, "wrong CPU");
-	lock->owner = SPINLOCK_OWNER_INIT;
-	lock->owner_cpu = -1;
+	WRITE_ONCE(lock->owner, SPINLOCK_OWNER_INIT);
+	WRITE_ONCE(lock->owner_cpu, -1);
 }
 
 void do_raw_write_lock(rwlock_t *lock)
diff --git a/kernel/module.c b/kernel/module.c
index 2325c9821f2a..9cb1437151ae 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -995,6 +995,8 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
 	strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
 
 	free_module(mod);
+	/* someone could wait for the module in add_unformed_module() */
+	wake_up_all(&module_wq);
 	return 0;
 out:
 	mutex_unlock(&module_mutex);
@@ -3351,8 +3353,7 @@ static bool finished_loading(const char *name)
 	sched_annotate_sleep();
 	mutex_lock(&module_mutex);
 	mod = find_module_all(name, strlen(name), true);
-	ret = !mod || mod->state == MODULE_STATE_LIVE
-		|| mod->state == MODULE_STATE_GOING;
+	ret = !mod || mod->state == MODULE_STATE_LIVE;
 	mutex_unlock(&module_mutex);
 
 	return ret;
@@ -3515,8 +3516,7 @@ again:
 	mutex_lock(&module_mutex);
 	old = find_module_all(mod->name, strlen(mod->name), true);
 	if (old != NULL) {
-		if (old->state == MODULE_STATE_COMING
-		    || old->state == MODULE_STATE_UNFORMED) {
+		if (old->state != MODULE_STATE_LIVE) {
 			/* Wait in case it fails to load. */
 			mutex_unlock(&module_mutex);
 			err = wait_event_interruptible(module_wq,
diff --git a/kernel/notifier.c b/kernel/notifier.c
index fd2c9acbcc19..0f70f1b6fdaa 100644
--- a/kernel/notifier.c
+++ b/kernel/notifier.c
@@ -552,7 +552,7 @@ NOKPROBE_SYMBOL(notify_die);
 
 int register_die_notifier(struct notifier_block *nb)
 {
-	vmalloc_sync_all();
+	vmalloc_sync_mappings();
 	return atomic_notifier_chain_register(&die_chain, nb);
 }
 EXPORT_SYMBOL_GPL(register_die_notifier);
diff --git a/kernel/padata.c b/kernel/padata.c
index e4a8f8d9b31a..6939111b3cbe 100644
--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -34,6 +34,8 @@
 
 #define MAX_OBJ_NUM 1000
 
+static void padata_free_pd(struct parallel_data *pd);
+
 static int padata_index_to_cpu(struct parallel_data *pd, int cpu_index)
 {
 	int cpu, target_cpu;
@@ -274,7 +276,12 @@ static void padata_reorder(struct parallel_data *pd)
 	 * The next object that needs serialization might have arrived to
 	 * the reorder queues in the meantime, we will be called again
 	 * from the timer function if no one else cares for it.
+	 *
+	 * Ensure reorder_objects is read after pd->lock is dropped so we see
+	 * an increment from another task in padata_do_serial.  Pairs with
+	 * smp_mb__after_atomic in padata_do_serial.
 	 */
+	smp_mb();
 	if (atomic_read(&pd->reorder_objects)
 			&& !(pinst->flags & PADATA_RESET))
 		mod_timer(&pd->timer, jiffies + HZ);
@@ -296,6 +303,7 @@ static void padata_serial_worker(struct work_struct *serial_work)
 	struct padata_serial_queue *squeue;
 	struct parallel_data *pd;
 	LIST_HEAD(local_list);
+	int cnt;
 
 	local_bh_disable();
 	squeue = container_of(serial_work, struct padata_serial_queue, work);
@@ -305,6 +313,8 @@ static void padata_serial_worker(struct work_struct *serial_work)
 	list_replace_init(&squeue->serial.list, &local_list);
 	spin_unlock(&squeue->serial.lock);
 
+	cnt = 0;
+
 	while (!list_empty(&local_list)) {
 		struct padata_priv *padata;
 
@@ -314,9 +324,12 @@ static void padata_serial_worker(struct work_struct *serial_work)
 		list_del_init(&padata->list);
 
 		padata->serial(padata);
-		atomic_dec(&pd->refcnt);
+		cnt++;
 	}
 	local_bh_enable();
+
+	if (atomic_sub_and_test(cnt, &pd->refcnt))
+		padata_free_pd(pd);
 }
 
 /**
@@ -343,6 +356,13 @@ void padata_do_serial(struct padata_priv *padata)
 	list_add_tail(&padata->list, &pqueue->reorder.list);
 	spin_unlock(&pqueue->reorder.lock);
 
+	/*
+	 * Ensure the atomic_inc of reorder_objects above is ordered correctly
+	 * with the trylock of pd->lock in padata_reorder.  Pairs with smp_mb
+	 * in padata_reorder.
+	 */
+	smp_mb__after_atomic();
+
 	put_cpu();
 
 	padata_reorder(pd);
@@ -432,7 +452,7 @@ static struct parallel_data *padata_alloc_pd(struct padata_instance *pinst,
 	setup_timer(&pd->timer, padata_reorder_timer, (unsigned long)pd);
 	atomic_set(&pd->seq_nr, -1);
 	atomic_set(&pd->reorder_objects, 0);
-	atomic_set(&pd->refcnt, 0);
+	atomic_set(&pd->refcnt, 1);
 	pd->pinst = pinst;
 	spin_lock_init(&pd->lock);
 
@@ -457,31 +477,6 @@ static void padata_free_pd(struct parallel_data *pd)
 	kfree(pd);
 }
 
-/* Flush all objects out of the padata queues. */
-static void padata_flush_queues(struct parallel_data *pd)
-{
-	int cpu;
-	struct padata_parallel_queue *pqueue;
-	struct padata_serial_queue *squeue;
-
-	for_each_cpu(cpu, pd->cpumask.pcpu) {
-		pqueue = per_cpu_ptr(pd->pqueue, cpu);
-		flush_work(&pqueue->work);
-	}
-
-	del_timer_sync(&pd->timer);
-
-	if (atomic_read(&pd->reorder_objects))
-		padata_reorder(pd);
-
-	for_each_cpu(cpu, pd->cpumask.cbcpu) {
-		squeue = per_cpu_ptr(pd->squeue, cpu);
-		flush_work(&squeue->work);
-	}
-
-	BUG_ON(atomic_read(&pd->refcnt) != 0);
-}
-
 static void __padata_start(struct padata_instance *pinst)
 {
 	pinst->flags |= PADATA_INIT;
@@ -495,10 +490,6 @@ static void __padata_stop(struct padata_instance *pinst)
 	pinst->flags &= ~PADATA_INIT;
 
 	synchronize_rcu();
-
-	get_online_cpus();
-	padata_flush_queues(pinst->pd);
-	put_online_cpus();
 }
 
 /* Replace the internal control structure with a new one. */
@@ -519,8 +510,8 @@ static void padata_replace(struct padata_instance *pinst,
 	if (!cpumask_equal(pd_old->cpumask.cbcpu, pd_new->cpumask.cbcpu))
 		notification_mask |= PADATA_CPU_SERIAL;
 
-	padata_flush_queues(pd_old);
-	padata_free_pd(pd_old);
+	if (atomic_dec_and_test(&pd_old->refcnt))
+		padata_free_pd(pd_old);
 
 	if (notification_mask)
 		blocking_notifier_call_chain(&pinst->cpumask_change_notifier,
@@ -623,8 +614,8 @@ int padata_set_cpumask(struct padata_instance *pinst, int cpumask_type,
 	struct cpumask *serial_mask, *parallel_mask;
 	int err = -EINVAL;
 
-	mutex_lock(&pinst->lock);
 	get_online_cpus();
+	mutex_lock(&pinst->lock);
 
 	switch (cpumask_type) {
 	case PADATA_CPU_PARALLEL:
@@ -642,8 +633,8 @@ int padata_set_cpumask(struct padata_instance *pinst, int cpumask_type,
 	err =  __padata_set_cpumasks(pinst, parallel_mask, serial_mask);
 
 out:
-	put_online_cpus();
 	mutex_unlock(&pinst->lock);
+	put_online_cpus();
 
 	return err;
 }
diff --git a/kernel/panic.c b/kernel/panic.c
index eb7bc6d60927..89198dca0180 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -144,6 +144,7 @@ void panic(const char *fmt, ...)
 	 * after setting panic_cpu) from invoking panic() again.
 	 */
 	local_irq_disable();
+	preempt_disable_notrace();
 
 	/*
 	 * It's possible to come here directly from a panic-assertion and
diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c
index 3976dd57db78..0eab538841fd 100644
--- a/kernel/pid_namespace.c
+++ b/kernel/pid_namespace.c
@@ -344,7 +344,7 @@ int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd)
 	}
 
 	read_lock(&tasklist_lock);
-	force_sig(SIGKILL, pid_ns->child_reaper);
+	send_sig(SIGKILL, pid_ns->child_reaper, 1);
 	read_unlock(&tasklist_lock);
 
 	do_exit(0);
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index b26dbc48c75b..81695a492ebe 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -256,6 +256,11 @@ void swsusp_show_speed(ktime_t start, ktime_t stop,
 			kps / 1000, (kps % 1000) / 10);
 }
 
+__weak int arch_resume_nosmt(void)
+{
+	return 0;
+}
+
 /**
  * create_image - Create a hibernation image.
  * @platform_mode: Whether or not to use the platform driver.
@@ -322,6 +327,10 @@ static int create_image(int platform_mode)
  Enable_cpus:
 	enable_nonboot_cpus();
 
+	/* Allow architectures to do nosmt-specific post-resume dances */
+	if (!in_suspend)
+		error = arch_resume_nosmt();
+
  Platform_finish:
 	platform_finish(platform_mode);
 
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index 4f0f0604f1c4..5dfac92521fa 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -732,8 +732,15 @@ zone_found:
 	 * We have found the zone. Now walk the radix tree to find the leaf node
 	 * for our PFN.
 	 */
+
+	/*
+	 * If the zone we wish to scan is the the current zone and the
+	 * pfn falls into the current node then we do not need to walk
+	 * the tree.
+	 */
 	node = bm->cur.node;
-	if (((pfn - zone->start_pfn) & ~BM_BLOCK_MASK) == bm->cur.node_pfn)
+	if (zone == bm->cur.zone &&
+	    ((pfn - zone->start_pfn) & ~BM_BLOCK_MASK) == bm->cur.node_pfn)
 		goto node_found;
 
 	node      = zone->rtree;
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 09f9842f9f42..362f177d2c84 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -356,7 +356,6 @@ DECLARE_WAIT_QUEUE_HEAD(log_wait);
 /* the next printk record to read by syslog(READ) or /proc/kmsg */
 static u64 syslog_seq;
 static u32 syslog_idx;
-static enum log_flags syslog_prev;
 static size_t syslog_partial;
 
 /* index and sequence number of the first record stored in the buffer */
@@ -370,7 +369,6 @@ static u32 log_next_idx;
 /* the next printk record to write to the console */
 static u64 console_seq;
 static u32 console_idx;
-static enum log_flags console_prev;
 
 /* the next printk record to read after the last 'clear' command */
 static u64 clear_seq;
@@ -385,6 +383,7 @@ static u32 clear_idx;
 /* record buffer */
 #define LOG_ALIGN __alignof__(struct printk_log)
 #define __LOG_BUF_LEN (1 << CONFIG_LOG_BUF_SHIFT)
+#define LOG_BUF_LEN_MAX (u32)(1 << 31)
 static char __log_buf[__LOG_BUF_LEN] __aligned(LOG_ALIGN);
 static char *log_buf = __log_buf;
 static u32 log_buf_len = __LOG_BUF_LEN;
@@ -639,27 +638,15 @@ static void append_char(char **pp, char *e, char c)
 }
 
 static ssize_t msg_print_ext_header(char *buf, size_t size,
-				    struct printk_log *msg, u64 seq,
-				    enum log_flags prev_flags)
+				    struct printk_log *msg, u64 seq)
 {
 	u64 ts_usec = msg->ts_nsec;
-	char cont = '-';
 
 	do_div(ts_usec, 1000);
 
-	/*
-	 * If we couldn't merge continuation line fragments during the print,
-	 * export the stored flags to allow an optional external merge of the
-	 * records. Merging the records isn't always neccessarily correct, like
-	 * when we hit a race during printing. In most cases though, it produces
-	 * better readable output. 'c' in the record flags mark the first
-	 * fragment of a line, '+' the following.
-	 */
-	if (msg->flags & LOG_CONT)
-		cont = (prev_flags & LOG_CONT) ? '+' : 'c';
-
 	return scnprintf(buf, size, "%u,%llu,%llu,%c;",
-		       (msg->facility << 3) | msg->level, seq, ts_usec, cont);
+		       (msg->facility << 3) | msg->level, seq, ts_usec,
+		       msg->flags & LOG_CONT ? 'c' : '-');
 }
 
 static ssize_t msg_print_ext_body(char *buf, size_t size,
@@ -714,7 +701,6 @@ static ssize_t msg_print_ext_body(char *buf, size_t size,
 struct devkmsg_user {
 	u64 seq;
 	u32 idx;
-	enum log_flags prev;
 	struct ratelimit_state rs;
 	struct mutex lock;
 	char buf[CONSOLE_EXT_LOG_MAX];
@@ -824,12 +810,11 @@ static ssize_t devkmsg_read(struct file *file, char __user *buf,
 
 	msg = log_from_idx(user->idx);
 	len = msg_print_ext_header(user->buf, sizeof(user->buf),
-				   msg, user->seq, user->prev);
+				   msg, user->seq);
 	len += msg_print_ext_body(user->buf + len, sizeof(user->buf) - len,
 				  log_dict(msg), msg->dict_len,
 				  log_text(msg), msg->text_len);
 
-	user->prev = msg->flags;
 	user->idx = log_next(user->idx);
 	user->seq++;
 	raw_spin_unlock_irq(&logbuf_lock);
@@ -999,18 +984,23 @@ void log_buf_kexec_setup(void)
 static unsigned long __initdata new_log_buf_len;
 
 /* we practice scaling the ring buffer by powers of 2 */
-static void __init log_buf_len_update(unsigned size)
+static void __init log_buf_len_update(u64 size)
 {
+	if (size > (u64)LOG_BUF_LEN_MAX) {
+		size = (u64)LOG_BUF_LEN_MAX;
+		pr_err("log_buf over 2G is not supported.\n");
+	}
+
 	if (size)
 		size = roundup_pow_of_two(size);
 	if (size > log_buf_len)
-		new_log_buf_len = size;
+		new_log_buf_len = (unsigned long)size;
 }
 
 /* save requested log_buf_len since it's too early to process it */
 static int __init log_buf_len_setup(char *str)
 {
-	unsigned int size;
+	u64 size;
 
 	if (!str)
 		return -EINVAL;
@@ -1060,7 +1050,7 @@ void __init setup_log_buf(int early)
 {
 	unsigned long flags;
 	char *new_log_buf;
-	int free;
+	unsigned int free;
 
 	if (log_buf != __log_buf)
 		return;
@@ -1080,7 +1070,7 @@ void __init setup_log_buf(int early)
 	}
 
 	if (unlikely(!new_log_buf)) {
-		pr_err("log_buf_len: %ld bytes not available\n",
+		pr_err("log_buf_len: %lu bytes not available\n",
 			new_log_buf_len);
 		return;
 	}
@@ -1093,8 +1083,8 @@ void __init setup_log_buf(int early)
 	memcpy(log_buf, __log_buf, __LOG_BUF_LEN);
 	raw_spin_unlock_irqrestore(&logbuf_lock, flags);
 
-	pr_info("log_buf_len: %d bytes\n", log_buf_len);
-	pr_info("early log buf free: %d(%d%%)\n",
+	pr_info("log_buf_len: %u bytes\n", log_buf_len);
+	pr_info("early log buf free: %u(%u%%)\n",
 		free, (free * 100) / __LOG_BUF_LEN);
 }
 
@@ -1215,26 +1205,12 @@ static size_t print_prefix(const struct printk_log *msg, bool syslog, char *buf)
 	return len;
 }
 
-static size_t msg_print_text(const struct printk_log *msg, enum log_flags prev,
-			     bool syslog, char *buf, size_t size)
+static size_t msg_print_text(const struct printk_log *msg, bool syslog, char *buf, size_t size)
 {
 	const char *text = log_text(msg);
 	size_t text_size = msg->text_len;
-	bool prefix = true;
-	bool newline = true;
 	size_t len = 0;
 
-	if ((prev & LOG_CONT) && !(msg->flags & LOG_PREFIX))
-		prefix = false;
-
-	if (msg->flags & LOG_CONT) {
-		if ((prev & LOG_CONT) && !(prev & LOG_NEWLINE))
-			prefix = false;
-
-		if (!(msg->flags & LOG_NEWLINE))
-			newline = false;
-	}
-
 	do {
 		const char *next = memchr(text, '\n', text_size);
 		size_t text_len;
@@ -1252,22 +1228,17 @@ static size_t msg_print_text(const struct printk_log *msg, enum log_flags prev,
 			    text_len + 1 >= size - len)
 				break;
 
-			if (prefix)
-				len += print_prefix(msg, syslog, buf + len);
+			len += print_prefix(msg, syslog, buf + len);
 			memcpy(buf + len, text, text_len);
 			len += text_len;
-			if (next || newline)
-				buf[len++] = '\n';
+			buf[len++] = '\n';
 		} else {
 			/* SYSLOG_ACTION_* buffer size only calculation */
-			if (prefix)
-				len += print_prefix(msg, syslog, NULL);
+			len += print_prefix(msg, syslog, NULL);
 			len += text_len;
-			if (next || newline)
-				len++;
+			len++;
 		}
 
-		prefix = true;
 		text = next;
 	} while (text);
 
@@ -1293,7 +1264,6 @@ static int syslog_print(char __user *buf, int size)
 			/* messages are gone, move to first one */
 			syslog_seq = log_first_seq;
 			syslog_idx = log_first_idx;
-			syslog_prev = 0;
 			syslog_partial = 0;
 		}
 		if (syslog_seq == log_next_seq) {
@@ -1303,13 +1273,11 @@ static int syslog_print(char __user *buf, int size)
 
 		skip = syslog_partial;
 		msg = log_from_idx(syslog_idx);
-		n = msg_print_text(msg, syslog_prev, true, text,
-				   LOG_LINE_MAX + PREFIX_MAX);
+		n = msg_print_text(msg, true, text, LOG_LINE_MAX + PREFIX_MAX);
 		if (n - syslog_partial <= size) {
 			/* message fits into buffer, move forward */
 			syslog_idx = log_next(syslog_idx);
 			syslog_seq++;
-			syslog_prev = msg->flags;
 			n -= syslog_partial;
 			syslog_partial = 0;
 		} else if (!len){
@@ -1352,7 +1320,6 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
 		u64 next_seq;
 		u64 seq;
 		u32 idx;
-		enum log_flags prev;
 
 		/*
 		 * Find first record that fits, including all following records,
@@ -1360,12 +1327,10 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
 		 */
 		seq = clear_seq;
 		idx = clear_idx;
-		prev = 0;
 		while (seq < log_next_seq) {
 			struct printk_log *msg = log_from_idx(idx);
 
-			len += msg_print_text(msg, prev, true, NULL, 0);
-			prev = msg->flags;
+			len += msg_print_text(msg, true, NULL, 0);
 			idx = log_next(idx);
 			seq++;
 		}
@@ -1373,12 +1338,10 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
 		/* move first record forward until length fits into the buffer */
 		seq = clear_seq;
 		idx = clear_idx;
-		prev = 0;
 		while (len > size && seq < log_next_seq) {
 			struct printk_log *msg = log_from_idx(idx);
 
-			len -= msg_print_text(msg, prev, true, NULL, 0);
-			prev = msg->flags;
+			len -= msg_print_text(msg, true, NULL, 0);
 			idx = log_next(idx);
 			seq++;
 		}
@@ -1391,7 +1354,7 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
 			struct printk_log *msg = log_from_idx(idx);
 			int textlen;
 
-			textlen = msg_print_text(msg, prev, true, text,
+			textlen = msg_print_text(msg, true, text,
 						 LOG_LINE_MAX + PREFIX_MAX);
 			if (textlen < 0) {
 				len = textlen;
@@ -1399,7 +1362,6 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
 			}
 			idx = log_next(idx);
 			seq++;
-			prev = msg->flags;
 
 			raw_spin_unlock_irq(&logbuf_lock);
 			if (copy_to_user(buf + len, text, textlen))
@@ -1412,7 +1374,6 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
 				/* messages are gone, move to next one */
 				seq = log_first_seq;
 				idx = log_first_idx;
-				prev = 0;
 			}
 		}
 	}
@@ -1513,7 +1474,6 @@ int do_syslog(int type, char __user *buf, int len, int source)
 			/* messages are gone, move to first one */
 			syslog_seq = log_first_seq;
 			syslog_idx = log_first_idx;
-			syslog_prev = 0;
 			syslog_partial = 0;
 		}
 		if (source == SYSLOG_FROM_PROC) {
@@ -1526,16 +1486,14 @@ int do_syslog(int type, char __user *buf, int len, int source)
 		} else {
 			u64 seq = syslog_seq;
 			u32 idx = syslog_idx;
-			enum log_flags prev = syslog_prev;
 
 			error = 0;
 			while (seq < log_next_seq) {
 				struct printk_log *msg = log_from_idx(idx);
 
-				error += msg_print_text(msg, prev, true, NULL, 0);
+				error += msg_print_text(msg, true, NULL, 0);
 				idx = log_next(idx);
 				seq++;
-				prev = msg->flags;
 			}
 			error -= syslog_partial;
 		}
@@ -1717,7 +1675,7 @@ static size_t cont_print_text(char *text, size_t size)
 	size_t textlen = 0;
 	size_t len;
 
-	if (cont.cons == 0 && (console_prev & LOG_NEWLINE)) {
+	if (cont.cons == 0) {
 		textlen += print_time(cont.ts_nsec, text);
 		size -= textlen;
 	}
@@ -1985,11 +1943,9 @@ static u64 syslog_seq;
 static u32 syslog_idx;
 static u64 console_seq;
 static u32 console_idx;
-static enum log_flags syslog_prev;
 static u64 log_first_seq;
 static u32 log_first_idx;
 static u64 log_next_seq;
-static enum log_flags console_prev;
 static struct cont {
 	size_t len;
 	size_t cons;
@@ -2001,15 +1957,15 @@ static char *log_dict(const struct printk_log *msg) { return NULL; }
 static struct printk_log *log_from_idx(u32 idx) { return NULL; }
 static u32 log_next(u32 idx) { return 0; }
 static ssize_t msg_print_ext_header(char *buf, size_t size,
-				    struct printk_log *msg, u64 seq,
-				    enum log_flags prev_flags) { return 0; }
+				    struct printk_log *msg,
+				    u64 seq) { return 0; }
 static ssize_t msg_print_ext_body(char *buf, size_t size,
 				  char *dict, size_t dict_len,
 				  char *text, size_t text_len) { return 0; }
 static void call_console_drivers(int level,
 				 const char *ext_text, size_t ext_len,
 				 const char *text, size_t len) {}
-static size_t msg_print_text(const struct printk_log *msg, enum log_flags prev,
+static size_t msg_print_text(const struct printk_log *msg,
 			     bool syslog, char *buf, size_t size) { return 0; }
 static size_t cont_print_text(char *text, size_t size) { return 0; }
 static bool suppress_message_printing(int level) { return false; }
@@ -2398,7 +2354,6 @@ again:
 			/* messages are gone, move to first one */
 			console_seq = log_first_seq;
 			console_idx = log_first_idx;
-			console_prev = 0;
 		} else {
 			len = 0;
 		}
@@ -2423,16 +2378,14 @@ skip:
 			 * will properly dump everything later.
 			 */
 			msg->flags &= ~LOG_NOCONS;
-			console_prev = msg->flags;
 			goto skip;
 		}
 
-		len += msg_print_text(msg, console_prev, false,
-				      text + len, sizeof(text) - len);
+		len += msg_print_text(msg, false, text + len, sizeof(text) - len);
 		if (nr_ext_console_drivers) {
 			ext_len = msg_print_ext_header(ext_text,
 						sizeof(ext_text),
-						msg, console_seq, console_prev);
+						msg, console_seq);
 			ext_len += msg_print_ext_body(ext_text + ext_len,
 						sizeof(ext_text) - ext_len,
 						log_dict(msg), msg->dict_len,
@@ -2440,7 +2393,6 @@ skip:
 		}
 		console_idx = log_next(console_idx);
 		console_seq++;
-		console_prev = msg->flags;
 		raw_spin_unlock(&logbuf_lock);
 
 		stop_critical_timings();	/* don't trace print latency */
@@ -2735,7 +2687,6 @@ void register_console(struct console *newcon)
 		raw_spin_lock_irqsave(&logbuf_lock, flags);
 		console_seq = syslog_seq;
 		console_idx = syslog_idx;
-		console_prev = syslog_prev;
 		raw_spin_unlock_irqrestore(&logbuf_lock, flags);
 		/*
 		 * We're about to replay the log buffer.  Only do this to the
@@ -3085,7 +3036,7 @@ bool kmsg_dump_get_line_nolock(struct kmsg_dumper *dumper, bool syslog,
 		goto out;
 
 	msg = log_from_idx(dumper->cur_idx);
-	l = msg_print_text(msg, 0, syslog, line, size);
+	l = msg_print_text(msg, syslog, line, size);
 
 	dumper->cur_idx = log_next(dumper->cur_idx);
 	dumper->cur_seq++;
@@ -3154,7 +3105,6 @@ bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog,
 	u32 idx;
 	u64 next_seq;
 	u32 next_idx;
-	enum log_flags prev;
 	size_t l = 0;
 	bool ret = false;
 
@@ -3177,27 +3127,23 @@ bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog,
 	/* calculate length of entire buffer */
 	seq = dumper->cur_seq;
 	idx = dumper->cur_idx;
-	prev = 0;
 	while (seq < dumper->next_seq) {
 		struct printk_log *msg = log_from_idx(idx);
 
-		l += msg_print_text(msg, prev, true, NULL, 0);
+		l += msg_print_text(msg, true, NULL, 0);
 		idx = log_next(idx);
 		seq++;
-		prev = msg->flags;
 	}
 
 	/* move first record forward until length fits into the buffer */
 	seq = dumper->cur_seq;
 	idx = dumper->cur_idx;
-	prev = 0;
-	while (l > size && seq < dumper->next_seq) {
+	while (l >= size && seq < dumper->next_seq) {
 		struct printk_log *msg = log_from_idx(idx);
 
-		l -= msg_print_text(msg, prev, true, NULL, 0);
+		l -= msg_print_text(msg, true, NULL, 0);
 		idx = log_next(idx);
 		seq++;
-		prev = msg->flags;
 	}
 
 	/* last message in next interation */
@@ -3208,10 +3154,9 @@ bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog,
 	while (seq < dumper->next_seq) {
 		struct printk_log *msg = log_from_idx(idx);
 
-		l += msg_print_text(msg, prev, syslog, buf + l, size - l);
+		l += msg_print_text(msg, syslog, buf + l, size - l);
 		idx = log_next(idx);
 		seq++;
-		prev = msg->flags;
 	}
 
 	dumper->next_seq = next_seq;
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index f39a7be98fc1..ea3370e205fb 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -74,9 +74,7 @@ void __ptrace_link(struct task_struct *child, struct task_struct *new_parent,
  */
 static void ptrace_link(struct task_struct *child, struct task_struct *new_parent)
 {
-	rcu_read_lock();
-	__ptrace_link(child, new_parent, __task_cred(new_parent));
-	rcu_read_unlock();
+	__ptrace_link(child, new_parent, current_cred());
 }
 
 /**
@@ -258,6 +256,9 @@ static int ptrace_check_attach(struct task_struct *child, bool ignore_state)
 
 static int ptrace_has_cap(struct user_namespace *ns, unsigned int mode)
 {
+	if (mode & PTRACE_MODE_SCHED)
+		return false;
+
 	if (mode & PTRACE_MODE_NOAUDIT)
 		return has_ns_capability_noaudit(current, ns, CAP_SYS_PTRACE);
 	else
@@ -319,15 +320,32 @@ static int __ptrace_may_access(struct task_struct *task, unsigned int mode)
 	return -EPERM;
 ok:
 	rcu_read_unlock();
+	/*
+	 * If a task drops privileges and becomes nondumpable (through a syscall
+	 * like setresuid()) while we are trying to access it, we must ensure
+	 * that the dumpability is read after the credentials; otherwise,
+	 * we may be able to attach to a task that we shouldn't be able to
+	 * attach to (as if the task had dropped privileges without becoming
+	 * nondumpable).
+	 * Pairs with a write barrier in commit_creds().
+	 */
+	smp_rmb();
 	mm = task->mm;
 	if (mm &&
 	    ((get_dumpable(mm) != SUID_DUMP_USER) &&
 	     !ptrace_has_cap(mm->user_ns, mode)))
 	    return -EPERM;
 
+	if (mode & PTRACE_MODE_SCHED)
+		return 0;
 	return security_ptrace_access_check(task, mode);
 }
 
+bool ptrace_may_access_sched(struct task_struct *task, unsigned int mode)
+{
+	return __ptrace_may_access(task, mode | PTRACE_MODE_SCHED);
+}
+
 bool ptrace_may_access(struct task_struct *task, unsigned int mode)
 {
 	int err;
@@ -700,6 +718,10 @@ static int ptrace_peek_siginfo(struct task_struct *child,
 	if (arg.nr < 0)
 		return -EINVAL;
 
+	/* Ensure arg.off fits in an unsigned long */
+	if (arg.off > ULONG_MAX)
+		return 0;
+
 	if (arg.flags & PTRACE_PEEKSIGINFO_SHARED)
 		pending = &child->signal->shared_pending;
 	else
@@ -707,18 +729,20 @@ static int ptrace_peek_siginfo(struct task_struct *child,
 
 	for (i = 0; i < arg.nr; ) {
 		siginfo_t info;
-		s32 off = arg.off + i;
+		unsigned long off = arg.off + i;
+		bool found = false;
 
 		spin_lock_irq(&child->sighand->siglock);
 		list_for_each_entry(q, &pending->list, list) {
 			if (!off--) {
+				found = true;
 				copy_siginfo(&info, &q->info);
 				break;
 			}
 		}
 		spin_unlock_irq(&child->sighand->siglock);
 
-		if (off >= 0) /* beyond the end of the list */
+		if (!found) /* beyond the end of the list */
 			break;
 
 #ifdef CONFIG_COMPAT
diff --git a/kernel/rcu/rcuperf.c b/kernel/rcu/rcuperf.c
index 123ccbd22449..2b8579d5a544 100644
--- a/kernel/rcu/rcuperf.c
+++ b/kernel/rcu/rcuperf.c
@@ -453,6 +453,10 @@ rcu_perf_cleanup(void)
 
 	if (torture_cleanup_begin())
 		return;
+	if (!cur_ops) {
+		torture_cleanup_end();
+		return;
+	}
 
 	if (reader_tasks) {
 		for (i = 0; i < nrealreaders; i++)
@@ -574,6 +578,7 @@ rcu_perf_init(void)
 			pr_alert(" %s", perf_ops[i]->name);
 		pr_alert("\n");
 		firsterr = -EINVAL;
+		cur_ops = NULL;
 		goto unwind;
 	}
 	if (cur_ops->init)
diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index bf08fee53dc7..5393bbcf3c1a 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -1595,6 +1595,10 @@ rcu_torture_cleanup(void)
 			cur_ops->cb_barrier();
 		return;
 	}
+	if (!cur_ops) {
+		torture_cleanup_end();
+		return;
+	}
 
 	rcu_torture_barrier_cleanup();
 	torture_stop_kthread(rcu_torture_stall, stall_task);
@@ -1730,6 +1734,7 @@ rcu_torture_init(void)
 			pr_alert(" %s", torture_ops[i]->name);
 		pr_alert("\n");
 		firsterr = -EINVAL;
+		cur_ops = NULL;
 		goto unwind;
 	}
 	if (cur_ops->fqs == NULL && fqs_duration != 0) {
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 6b3fff6a6437..82cec9a666e7 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -1162,7 +1162,8 @@ static int __set_cpus_allowed_ptr(struct task_struct *p,
 	if (cpumask_equal(&p->cpus_allowed, new_mask))
 		goto out;
 
-	if (!cpumask_intersects(new_mask, cpu_valid_mask)) {
+	dest_cpu = cpumask_any_and(cpu_valid_mask, new_mask);
+	if (dest_cpu >= nr_cpu_ids) {
 		ret = -EINVAL;
 		goto out;
 	}
@@ -1183,7 +1184,6 @@ static int __set_cpus_allowed_ptr(struct task_struct *p,
 	if (cpumask_test_cpu(task_cpu(p), new_mask))
 		goto out;
 
-	dest_cpu = cpumask_any_and(cpu_valid_mask, new_mask);
 	if (task_running(rq, p) || p->state == TASK_WAKING) {
 		struct migration_arg arg = { p, dest_cpu };
 		/* Need help from migration thread: drop lock and wait. */
@@ -7355,11 +7355,22 @@ static int cpuset_cpu_inactive(unsigned int cpu)
 	return 0;
 }
 
+#ifdef CONFIG_SCHED_SMT
+atomic_t sched_smt_present = ATOMIC_INIT(0);
+#endif
+
 int sched_cpu_activate(unsigned int cpu)
 {
 	struct rq *rq = cpu_rq(cpu);
 	unsigned long flags;
 
+#ifdef CONFIG_SCHED_SMT
+	/*
+	 * When going up, increment the number of cores with SMT present.
+	 */
+	if (cpumask_weight(cpu_smt_mask(cpu)) == 2)
+		atomic_inc(&sched_smt_present);
+#endif
 	set_cpu_active(cpu, true);
 
 	if (sched_smp_initialized) {
@@ -7408,6 +7419,14 @@ int sched_cpu_deactivate(unsigned int cpu)
 	else
 		synchronize_rcu();
 
+#ifdef CONFIG_SCHED_SMT
+	/*
+	 * When going down, decrement the number of cores with SMT present.
+	 */
+	if (cpumask_weight(cpu_smt_mask(cpu)) == 2)
+		atomic_dec(&sched_smt_present);
+#endif
+
 	if (!sched_smp_initialized)
 		return 0;
 
@@ -8455,10 +8474,6 @@ static int cpu_cgroup_can_attach(struct cgroup_taskset *tset)
 #ifdef CONFIG_RT_GROUP_SCHED
 		if (!sched_rt_can_attach(css_tg(css), task))
 			return -EINVAL;
-#else
-		/* We don't support RT-tasks being in separate groups */
-		if (task->sched_class != &fair_sched_class)
-			return -EINVAL;
 #endif
 		/*
 		 * Serialize against wake_up_new_task() such that if its
@@ -8493,6 +8508,8 @@ static void cpu_cgroup_attach(struct cgroup_taskset *tset)
 static int cpu_shares_write_u64(struct cgroup_subsys_state *css,
 				struct cftype *cftype, u64 shareval)
 {
+	if (shareval > scale_load_down(ULONG_MAX))
+		shareval = MAX_SHARES;
 	return sched_group_set_shares(css_tg(css), scale_load(shareval));
 }
 
@@ -8592,8 +8609,10 @@ int tg_set_cfs_quota(struct task_group *tg, long cfs_quota_us)
 	period = ktime_to_ns(tg->cfs_bandwidth.period);
 	if (cfs_quota_us < 0)
 		quota = RUNTIME_INF;
-	else
+	else if ((u64)cfs_quota_us <= U64_MAX / NSEC_PER_USEC)
 		quota = (u64)cfs_quota_us * NSEC_PER_USEC;
+	else
+		return -EINVAL;
 
 	return tg_set_cfs_bandwidth(tg, period, quota);
 }
@@ -8615,6 +8634,9 @@ int tg_set_cfs_period(struct task_group *tg, long cfs_period_us)
 {
 	u64 quota, period;
 
+	if ((u64)cfs_period_us > U64_MAX / NSEC_PER_USEC)
+		return -EINVAL;
+
 	period = (u64)cfs_period_us * NSEC_PER_USEC;
 	quota = tg->cfs_bandwidth.quota;
 
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 0c91d72f3e8f..5e65c7eea872 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -1925,6 +1925,10 @@ static u64 numa_get_avg_runtime(struct task_struct *p, u64 *period)
 	if (p->last_task_numa_placement) {
 		delta = runtime - p->last_sum_exec_runtime;
 		*period = now - p->last_task_numa_placement;
+
+		/* Avoid time going backwards, prevent potential divide error: */
+		if (unlikely((s64)*period < 0))
+			*period = 0;
 	} else {
 		delta = p->se.avg.load_sum / p->se.load.weight;
 		*period = LOAD_AVG_MAX;
@@ -2253,13 +2257,23 @@ no_join:
 	return;
 }
 
-void task_numa_free(struct task_struct *p)
+/*
+ * Get rid of NUMA staticstics associated with a task (either current or dead).
+ * If @final is set, the task is dead and has reached refcount zero, so we can
+ * safely free all relevant data structures. Otherwise, there might be
+ * concurrent reads from places like load balancing and procfs, and we should
+ * reset the data back to default state without freeing ->numa_faults.
+ */
+void task_numa_free(struct task_struct *p, bool final)
 {
 	struct numa_group *grp = p->numa_group;
-	void *numa_faults = p->numa_faults;
+	unsigned long *numa_faults = p->numa_faults;
 	unsigned long flags;
 	int i;
 
+	if (!numa_faults)
+		return;
+
 	if (grp) {
 		spin_lock_irqsave(&grp->lock, flags);
 		for (i = 0; i < NR_NUMA_HINT_FAULT_STATS * nr_node_ids; i++)
@@ -2272,8 +2286,14 @@ void task_numa_free(struct task_struct *p)
 		put_numa_group(grp);
 	}
 
-	p->numa_faults = NULL;
-	kfree(numa_faults);
+	if (final) {
+		p->numa_faults = NULL;
+		kfree(numa_faults);
+	} else {
+		p->total_numa_faults = 0;
+		for (i = 0; i < NR_NUMA_HINT_FAULT_STATS * nr_node_ids; i++)
+			numa_faults[i] = 0;
+	}
 }
 
 /*
@@ -3862,6 +3882,8 @@ static void __account_cfs_rq_runtime(struct cfs_rq *cfs_rq, u64 delta_exec)
 	if (likely(cfs_rq->runtime_remaining > 0))
 		return;
 
+	if (cfs_rq->throttled)
+		return;
 	/*
 	 * if we're unable to extend our runtime we resched so that the active
 	 * hierarchy can be throttled
@@ -4057,6 +4079,9 @@ static u64 distribute_cfs_runtime(struct cfs_bandwidth *cfs_b,
 		if (!cfs_rq_throttled(cfs_rq))
 			goto next;
 
+		/* By the above check, this should never be true */
+		SCHED_WARN_ON(cfs_rq->runtime_remaining > 0);
+
 		runtime = -cfs_rq->runtime_remaining + 1;
 		if (runtime > remaining)
 			runtime = remaining;
@@ -4347,12 +4372,15 @@ static enum hrtimer_restart sched_cfs_slack_timer(struct hrtimer *timer)
 	return HRTIMER_NORESTART;
 }
 
+extern const u64 max_cfs_quota_period;
+
 static enum hrtimer_restart sched_cfs_period_timer(struct hrtimer *timer)
 {
 	struct cfs_bandwidth *cfs_b =
 		container_of(timer, struct cfs_bandwidth, period_timer);
 	int overrun;
 	int idle = 0;
+	int count = 0;
 
 	raw_spin_lock(&cfs_b->lock);
 	for (;;) {
@@ -4360,6 +4388,36 @@ static enum hrtimer_restart sched_cfs_period_timer(struct hrtimer *timer)
 		if (!overrun)
 			break;
 
+		if (++count > 3) {
+			u64 new, old = ktime_to_ns(cfs_b->period);
+
+			/*
+			 * Grow period by a factor of 2 to avoid losing precision.
+			 * Precision loss in the quota/period ratio can cause __cfs_schedulable
+			 * to fail.
+			 */
+			new = old * 2;
+			if (new < max_cfs_quota_period) {
+				cfs_b->period = ns_to_ktime(new);
+				cfs_b->quota *= 2;
+
+				pr_warn_ratelimited(
+	"cfs_period_timer[cpu%d]: period too short, scaling up (new cfs_period_us = %lld, cfs_quota_us = %lld)\n",
+					smp_processor_id(),
+					div_u64(new, NSEC_PER_USEC),
+					div_u64(cfs_b->quota, NSEC_PER_USEC));
+			} else {
+				pr_warn_ratelimited(
+	"cfs_period_timer[cpu%d]: period too short, but cannot scale up without losing precision (cfs_period_us = %lld, cfs_quota_us = %lld)\n",
+					smp_processor_id(),
+					div_u64(old, NSEC_PER_USEC),
+					div_u64(cfs_b->quota, NSEC_PER_USEC));
+			}
+
+			/* reset count so we don't come right back in here */
+			count = 0;
+		}
+
 		idle = do_sched_cfs_period_timer(cfs_b, overrun);
 	}
 	if (idle)
@@ -6634,10 +6692,10 @@ static void update_cfs_rq_h_load(struct cfs_rq *cfs_rq)
 	if (cfs_rq->last_h_load_update == now)
 		return;
 
-	cfs_rq->h_load_next = NULL;
+	WRITE_ONCE(cfs_rq->h_load_next, NULL);
 	for_each_sched_entity(se) {
 		cfs_rq = cfs_rq_of(se);
-		cfs_rq->h_load_next = se;
+		WRITE_ONCE(cfs_rq->h_load_next, se);
 		if (cfs_rq->last_h_load_update == now)
 			break;
 	}
@@ -6647,7 +6705,7 @@ static void update_cfs_rq_h_load(struct cfs_rq *cfs_rq)
 		cfs_rq->last_h_load_update = now;
 	}
 
-	while ((se = cfs_rq->h_load_next) != NULL) {
+	while ((se = READ_ONCE(cfs_rq->h_load_next)) != NULL) {
 		load = cfs_rq->h_load;
 		load = div64_ul(load * se->avg.load_avg,
 			cfs_rq_load_avg(cfs_rq) + 1);
@@ -7879,9 +7937,10 @@ more_balance:
 out_balanced:
 	/*
 	 * We reach balance although we may have faced some affinity
-	 * constraints. Clear the imbalance flag if it was set.
+	 * constraints. Clear the imbalance flag only if other tasks got
+	 * a chance to move and fix the imbalance.
 	 */
-	if (sd_parent) {
+	if (sd_parent && !(env.flags & LBF_ALL_PINNED)) {
 		int *group_imbalance = &sd_parent->groups->sgc->imbalance;
 
 		if (*group_imbalance)
@@ -7899,13 +7958,22 @@ out_all_pinned:
 	sd->nr_balance_failed = 0;
 
 out_one_pinned:
+	ld_moved = 0;
+
+	/*
+	 * idle_balance() disregards balance intervals, so we could repeatedly
+	 * reach this code, which would lead to balance_interval skyrocketting
+	 * in a short amount of time. Skip the balance_interval increase logic
+	 * to avoid that.
+	 */
+	if (env.idle == CPU_NEWLY_IDLE)
+		goto out;
+
 	/* tune up the balancing interval */
 	if (((env.flags & LBF_ALL_PINNED) &&
 			sd->balance_interval < MAX_PINNED_INTERVAL) ||
 			(sd->balance_interval < sd->max_interval))
 		sd->balance_interval *= 2;
-
-	ld_moved = 0;
 out:
 	return ld_moved;
 }
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index ec6e838e991a..819bd5fb0264 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -2,6 +2,7 @@
 #include <linux/sched.h>
 #include <linux/sched/sysctl.h>
 #include <linux/sched/rt.h>
+#include <linux/sched/smt.h>
 #include <linux/u64_stats_sync.h>
 #include <linux/sched/deadline.h>
 #include <linux/kernel_stat.h>
@@ -72,7 +73,13 @@ static inline void update_idle_core(struct rq *rq) { }
 #ifdef CONFIG_64BIT
 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
 # define scale_load(w)		((w) << SCHED_FIXEDPOINT_SHIFT)
-# define scale_load_down(w)	((w) >> SCHED_FIXEDPOINT_SHIFT)
+# define scale_load_down(w) \
+({ \
+	unsigned long __w = (w); \
+	if (__w) \
+		__w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT); \
+	__w; \
+})
 #else
 # define NICE_0_LOAD_SHIFT	(SCHED_FIXEDPOINT_SHIFT)
 # define scale_load(w)		(w)
diff --git a/kernel/signal.c b/kernel/signal.c
index c091dcc9f19b..bedca1629f26 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -71,10 +71,19 @@ static int sig_task_ignored(struct task_struct *t, int sig, bool force)
 
 	handler = sig_handler(t, sig);
 
+	/* SIGKILL and SIGSTOP may not be sent to the global init */
+	if (unlikely(is_global_init(t) && sig_kernel_only(sig)))
+		return true;
+
 	if (unlikely(t->signal->flags & SIGNAL_UNKILLABLE) &&
 	    handler == SIG_DFL && !(force && sig_kernel_only(sig)))
 		return 1;
 
+	/* Only allow kernel generated signals to this kthread */
+	if (unlikely((t->flags & PF_KTHREAD) &&
+		     (handler == SIG_KTHREAD_KERNEL) && !force))
+		return true;
+
 	return sig_handler_ignored(handler, sig);
 }
 
@@ -364,27 +373,32 @@ __sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimi
 {
 	struct sigqueue *q = NULL;
 	struct user_struct *user;
+	int sigpending;
 
 	/*
 	 * Protect access to @t credentials. This can go away when all
 	 * callers hold rcu read lock.
+	 *
+	 * NOTE! A pending signal will hold on to the user refcount,
+	 * and we get/put the refcount only when the sigpending count
+	 * changes from/to zero.
 	 */
 	rcu_read_lock();
-	user = get_uid(__task_cred(t)->user);
-	atomic_inc(&user->sigpending);
+	user = __task_cred(t)->user;
+	sigpending = atomic_inc_return(&user->sigpending);
+	if (sigpending == 1)
+		get_uid(user);
 	rcu_read_unlock();
 
-	if (override_rlimit ||
-	    atomic_read(&user->sigpending) <=
-			task_rlimit(t, RLIMIT_SIGPENDING)) {
+	if (override_rlimit || likely(sigpending <= task_rlimit(t, RLIMIT_SIGPENDING))) {
 		q = kmem_cache_alloc(sigqueue_cachep, flags);
 	} else {
 		print_dropped_signal(sig);
 	}
 
 	if (unlikely(q == NULL)) {
-		atomic_dec(&user->sigpending);
-		free_uid(user);
+		if (atomic_dec_and_test(&user->sigpending))
+			free_uid(user);
 	} else {
 		INIT_LIST_HEAD(&q->list);
 		q->flags = 0;
@@ -398,8 +412,8 @@ static void __sigqueue_free(struct sigqueue *q)
 {
 	if (q->flags & SIGQUEUE_PREALLOC)
 		return;
-	atomic_dec(&q->user->sigpending);
-	free_uid(q->user);
+	if (atomic_dec_and_test(&q->user->sigpending))
+		free_uid(q->user);
 	kmem_cache_free(sigqueue_cachep, q);
 }
 
@@ -1646,7 +1660,7 @@ bool do_notify_parent(struct task_struct *tsk, int sig)
 		 * This is only possible if parent == real_parent.
 		 * Check if it has changed security domain.
 		 */
-		if (tsk->parent_exec_id != tsk->parent->self_exec_id)
+		if (tsk->parent_exec_id != READ_ONCE(tsk->parent->self_exec_id))
 			sig = SIGCHLD;
 	}
 
@@ -2244,6 +2258,8 @@ relock:
 	if (signal_group_exit(signal)) {
 		ksig->info.si_signo = signr = SIGKILL;
 		sigdelset(&current->pending.signal, SIGKILL);
+		trace_signal_deliver(SIGKILL, SEND_SIG_NOINFO,
+				&sighand->action[SIGKILL - 1]);
 		recalc_sigpending();
 		goto fatal;
 	}
diff --git a/kernel/sys.c b/kernel/sys.c
index 6c4e9b533258..157277cbf83a 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1762,7 +1762,7 @@ static int validate_prctl_map(struct prctl_mm_map *prctl_map)
 	((unsigned long)prctl_map->__m1 __op				\
 	 (unsigned long)prctl_map->__m2) ? 0 : -EINVAL
 	error  = __prctl_check_order(start_code, <, end_code);
-	error |= __prctl_check_order(start_data, <, end_data);
+	error |= __prctl_check_order(start_data,<=, end_data);
 	error |= __prctl_check_order(start_brk, <=, brk);
 	error |= __prctl_check_order(arg_start, <=, arg_end);
 	error |= __prctl_check_order(env_start, <=, env_end);
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index efd340a510a9..34449ec0689d 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -124,7 +124,9 @@ static int zero;
 static int __maybe_unused one = 1;
 static int __maybe_unused two = 2;
 static int __maybe_unused four = 4;
+static unsigned long zero_ul;
 static unsigned long one_ul = 1;
+static unsigned long long_max = LONG_MAX;
 static int one_hundred = 100;
 static int one_thousand = 1000;
 #ifdef CONFIG_PRINTK
@@ -1396,7 +1398,7 @@ static struct ctl_table vm_table[] = {
 		.procname	= "drop_caches",
 		.data		= &sysctl_drop_caches,
 		.maxlen		= sizeof(int),
-		.mode		= 0644,
+		.mode		= 0200,
 		.proc_handler	= drop_caches_sysctl_handler,
 		.extra1		= &one,
 		.extra2		= &four,
@@ -1682,6 +1684,8 @@ static struct ctl_table fs_table[] = {
 		.maxlen		= sizeof(files_stat.max_files),
 		.mode		= 0644,
 		.proc_handler	= proc_doulongvec_minmax,
+		.extra1		= &zero_ul,
+		.extra2		= &long_max,
 	},
 	{
 		.procname	= "nr_open",
@@ -2523,8 +2527,10 @@ static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int
 			if (neg)
 				continue;
 			val = convmul * val / convdiv;
-			if ((min && val < *min) || (max && val > *max))
-				continue;
+			if ((min && val < *min) || (max && val > *max)) {
+				err = -EINVAL;
+				break;
+			}
 			*i = val;
 		} else {
 			val = convdiv * (*i) / convmul;
diff --git a/kernel/taskstats.c b/kernel/taskstats.c
index cbb387a265db..23df1fbad4b4 100644
--- a/kernel/taskstats.c
+++ b/kernel/taskstats.c
@@ -559,25 +559,33 @@ static int taskstats_user_cmd(struct sk_buff *skb, struct genl_info *info)
 static struct taskstats *taskstats_tgid_alloc(struct task_struct *tsk)
 {
 	struct signal_struct *sig = tsk->signal;
-	struct taskstats *stats;
+	struct taskstats *stats_new, *stats;
 
-	if (sig->stats || thread_group_empty(tsk))
-		goto ret;
+	/* Pairs with smp_store_release() below. */
+	stats = smp_load_acquire(&sig->stats);
+	if (stats || thread_group_empty(tsk))
+		return stats;
 
 	/* No problem if kmem_cache_zalloc() fails */
-	stats = kmem_cache_zalloc(taskstats_cache, GFP_KERNEL);
+	stats_new = kmem_cache_zalloc(taskstats_cache, GFP_KERNEL);
 
 	spin_lock_irq(&tsk->sighand->siglock);
-	if (!sig->stats) {
-		sig->stats = stats;
-		stats = NULL;
+	stats = sig->stats;
+	if (!stats) {
+		/*
+		 * Pairs with smp_store_release() above and order the
+		 * kmem_cache_zalloc().
+		 */
+		smp_store_release(&sig->stats, stats_new);
+		stats = stats_new;
+		stats_new = NULL;
 	}
 	spin_unlock_irq(&tsk->sighand->siglock);
 
-	if (stats)
-		kmem_cache_free(taskstats_cache, stats);
-ret:
-	return sig->stats;
+	if (stats_new)
+		kmem_cache_free(taskstats_cache, stats_new);
+
+	return stats;
 }
 
 /* Send pid data out on exit */
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index a0ee81f49a87..6aef4a0bed29 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -544,7 +544,7 @@ static int alarm_timer_create(struct k_itimer *new_timer)
 	enum  alarmtimer_type type;
 
 	if (!alarmtimer_get_rtcdev())
-		return -ENOTSUPP;
+		return -EOPNOTSUPP;
 
 	if (!capable(CAP_WAKE_ALARM))
 		return -EPERM;
@@ -586,7 +586,7 @@ static void alarm_timer_get(struct k_itimer *timr,
 static int alarm_timer_del(struct k_itimer *timr)
 {
 	if (!rtcdev)
-		return -ENOTSUPP;
+		return -EOPNOTSUPP;
 
 	if (alarm_try_to_cancel(&timr->it.alarm.alarmtimer) < 0)
 		return TIMER_RETRY;
@@ -610,7 +610,7 @@ static int alarm_timer_set(struct k_itimer *timr, int flags,
 	ktime_t exp;
 
 	if (!rtcdev)
-		return -ENOTSUPP;
+		return -EOPNOTSUPP;
 
 	if (flags & ~TIMER_ABSTIME)
 		return -EINVAL;
@@ -772,7 +772,7 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
 	struct restart_block *restart;
 
 	if (!alarmtimer_get_rtcdev())
-		return -ENOTSUPP;
+		return -EOPNOTSUPP;
 
 	if (flags & ~TIMER_ABSTIME)
 		return -EINVAL;
diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index 7e4fad75acaa..2924ff544c9e 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -272,8 +272,15 @@ static void clocksource_watchdog(unsigned long data)
 	next_cpu = cpumask_next(raw_smp_processor_id(), cpu_online_mask);
 	if (next_cpu >= nr_cpu_ids)
 		next_cpu = cpumask_first(cpu_online_mask);
-	watchdog_timer.expires += WATCHDOG_INTERVAL;
-	add_timer_on(&watchdog_timer, next_cpu);
+
+	/*
+	 * Arm timer if not already pending: could race with concurrent
+	 * pair clocksource_stop_watchdog() clocksource_start_watchdog().
+	 */
+	if (!timer_pending(&watchdog_timer)) {
+		watchdog_timer.expires += WATCHDOG_INTERVAL;
+		add_timer_on(&watchdog_timer, next_cpu);
+	}
 out:
 	spin_unlock(&watchdog_lock);
 }
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index c93729661be0..f31637ced7fa 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -870,7 +870,8 @@ static int enqueue_hrtimer(struct hrtimer *timer,
 
 	base->cpu_base->active_bases |= 1 << base->index;
 
-	timer->state = HRTIMER_STATE_ENQUEUED;
+	/* Pairs with the lockless read in hrtimer_is_queued() */
+	WRITE_ONCE(timer->state, HRTIMER_STATE_ENQUEUED);
 
 	return timerqueue_add(&base->active, &timer->node);
 }
@@ -892,7 +893,8 @@ static void __remove_hrtimer(struct hrtimer *timer,
 	struct hrtimer_cpu_base *cpu_base = base->cpu_base;
 	u8 state = timer->state;
 
-	timer->state = newstate;
+	/* Pairs with the lockless read in hrtimer_is_queued() */
+	WRITE_ONCE(timer->state, newstate);
 	if (!(state & HRTIMER_STATE_ENQUEUED))
 		return;
 
@@ -919,8 +921,9 @@ static void __remove_hrtimer(struct hrtimer *timer,
 static inline int
 remove_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base, bool restart)
 {
-	if (hrtimer_is_queued(timer)) {
-		u8 state = timer->state;
+	u8 state = timer->state;
+
+	if (state & HRTIMER_STATE_ENQUEUED) {
 		int reprogram;
 
 		/*
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 6df8927c58a5..4bdb59604526 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -42,6 +42,7 @@ static u64			tick_length_base;
 #define MAX_TICKADJ		500LL		/* usecs */
 #define MAX_TICKADJ_SCALED \
 	(((MAX_TICKADJ * NSEC_PER_USEC) << NTP_SCALE_SHIFT) / NTP_INTERVAL_FREQ)
+#define MAX_TAI_OFFSET		100000
 
 /*
  * phase-lock loop variables
@@ -639,7 +640,8 @@ static inline void process_adjtimex_modes(struct timex *txc,
 		time_constant = max(time_constant, 0l);
 	}
 
-	if (txc->modes & ADJ_TAI && txc->constant > 0)
+	if (txc->modes & ADJ_TAI &&
+			txc->constant >= 0 && txc->constant <= MAX_TAI_OFFSET)
 		*time_tai = txc->constant;
 
 	if (txc->modes & ADJ_OFFSET)
diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index b625cc7fcc1c..b5603248d841 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -1586,21 +1586,23 @@ void timer_clear_idle(void)
 static int collect_expired_timers(struct timer_base *base,
 				  struct hlist_head *heads)
 {
+	unsigned long now = READ_ONCE(jiffies);
+
 	/*
 	 * NOHZ optimization. After a long idle sleep we need to forward the
 	 * base to current jiffies. Avoid a loop by searching the bitfield for
 	 * the next expiring timer.
 	 */
-	if ((long)(jiffies - base->clk) > 2) {
+	if ((long)(now - base->clk) > 2) {
 		unsigned long next = __next_timer_interrupt(base);
 
 		/*
 		 * If the next timer is ahead of time forward to current
 		 * jiffies, otherwise forward to the next expiry time:
 		 */
-		if (time_after(next, jiffies)) {
+		if (time_after(next, now)) {
 			/* The call site will increment clock! */
-			base->clk = jiffies - 1;
+			base->clk = now - 1;
 			return 0;
 		}
 		base->clk = next;
diff --git a/kernel/time/timer_list.c b/kernel/time/timer_list.c
index 1407ed20ea93..b7c5d230b4b2 100644
--- a/kernel/time/timer_list.c
+++ b/kernel/time/timer_list.c
@@ -299,23 +299,6 @@ static inline void timer_list_header(struct seq_file *m, u64 now)
 	SEQ_printf(m, "\n");
 }
 
-static int timer_list_show(struct seq_file *m, void *v)
-{
-	struct timer_list_iter *iter = v;
-
-	if (iter->cpu == -1 && !iter->second_pass)
-		timer_list_header(m, iter->now);
-	else if (!iter->second_pass)
-		print_cpu(m, iter->cpu, iter->now);
-#ifdef CONFIG_GENERIC_CLOCKEVENTS
-	else if (iter->cpu == -1 && iter->second_pass)
-		timer_list_show_tickdevices_header(m);
-	else
-		print_tickdevice(m, tick_get_device(iter->cpu), iter->cpu);
-#endif
-	return 0;
-}
-
 void sysrq_timer_list_show(void)
 {
 	u64 now = ktime_to_ns(ktime_get());
@@ -334,6 +317,24 @@ void sysrq_timer_list_show(void)
 	return;
 }
 
+#ifdef CONFIG_PROC_FS
+static int timer_list_show(struct seq_file *m, void *v)
+{
+	struct timer_list_iter *iter = v;
+
+	if (iter->cpu == -1 && !iter->second_pass)
+		timer_list_header(m, iter->now);
+	else if (!iter->second_pass)
+		print_cpu(m, iter->cpu, iter->now);
+#ifdef CONFIG_GENERIC_CLOCKEVENTS
+	else if (iter->cpu == -1 && iter->second_pass)
+		timer_list_show_tickdevices_header(m);
+	else
+		print_tickdevice(m, tick_get_device(iter->cpu), iter->cpu);
+#endif
+	return 0;
+}
+
 static void *move_iter(struct timer_list_iter *iter, loff_t offset)
 {
 	for (; offset; offset--) {
@@ -405,3 +406,4 @@ static int __init init_timer_list_procfs(void)
 	return 0;
 }
 __initcall(init_timer_list_procfs);
+#endif
diff --git a/kernel/time/timer_stats.c b/kernel/time/timer_stats.c
index 087204c733eb..c74920f318c5 100644
--- a/kernel/time/timer_stats.c
+++ b/kernel/time/timer_stats.c
@@ -417,7 +417,7 @@ static int __init init_tstats_procfs(void)
 {
 	struct proc_dir_entry *pe;
 
-	pe = proc_create("timer_stats", 0644, NULL, &tstats_fops);
+	pe = proc_create("timer_stats", 0600, NULL, &tstats_fops);
 	if (!pe)
 		return -ENOMEM;
 	return 0;
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 8f4227d4cd39..2ae98f8bce81 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -32,6 +32,7 @@
 #include <linux/list.h>
 #include <linux/hash.h>
 #include <linux/rcupdate.h>
+#include <linux/kprobes.h>
 
 #include <trace/events/sched.h>
 
@@ -608,8 +609,7 @@ static int function_stat_show(struct seq_file *m, void *v)
 	}
 
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
-	avg = rec->time;
-	do_div(avg, rec->counter);
+	avg = div64_ul(rec->time, rec->counter);
 	if (tracing_thresh && (avg < tracing_thresh))
 		goto out;
 #endif
@@ -635,7 +635,8 @@ static int function_stat_show(struct seq_file *m, void *v)
 		 * Divide only 1000 for ns^2 -> us^2 conversion.
 		 * trace_print_graph_duration will divide 1000 again.
 		 */
-		do_div(stddev, rec->counter * (rec->counter - 1) * 1000);
+		stddev = div64_ul(stddev,
+				  rec->counter * (rec->counter - 1) * 1000);
 	}
 
 	trace_seq_init(&s);
@@ -1630,6 +1631,11 @@ static bool test_rec_ops_needs_regs(struct dyn_ftrace *rec)
 	return  keep_regs;
 }
 
+static struct ftrace_ops *
+ftrace_find_tramp_ops_any(struct dyn_ftrace *rec);
+static struct ftrace_ops *
+ftrace_find_tramp_ops_next(struct dyn_ftrace *rec, struct ftrace_ops *ops);
+
 static bool __ftrace_hash_rec_update(struct ftrace_ops *ops,
 				     int filter_hash,
 				     bool inc)
@@ -1758,15 +1764,17 @@ static bool __ftrace_hash_rec_update(struct ftrace_ops *ops,
 			}
 
 			/*
-			 * If the rec had TRAMP enabled, then it needs to
-			 * be cleared. As TRAMP can only be enabled iff
-			 * there is only a single ops attached to it.
-			 * In otherwords, always disable it on decrementing.
-			 * In the future, we may set it if rec count is
-			 * decremented to one, and the ops that is left
-			 * has a trampoline.
+			 * The TRAMP needs to be set only if rec count
+			 * is decremented to one, and the ops that is
+			 * left has a trampoline. As TRAMP can only be
+			 * enabled if there is only a single ops attached
+			 * to it.
 			 */
-			rec->flags &= ~FTRACE_FL_TRAMP;
+			if (ftrace_rec_count(rec) == 1 &&
+			    ftrace_find_tramp_ops_any(rec))
+				rec->flags |= FTRACE_FL_TRAMP;
+			else
+				rec->flags &= ~FTRACE_FL_TRAMP;
 
 			/*
 			 * flags will be cleared in ftrace_check_record()
@@ -1959,11 +1967,6 @@ static void print_ip_ins(const char *fmt, const unsigned char *p)
 		printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]);
 }
 
-static struct ftrace_ops *
-ftrace_find_tramp_ops_any(struct dyn_ftrace *rec);
-static struct ftrace_ops *
-ftrace_find_tramp_ops_next(struct dyn_ftrace *rec, struct ftrace_ops *ops);
-
 enum ftrace_bug_type ftrace_bug_type;
 const void *ftrace_expected;
 
@@ -5246,7 +5249,7 @@ void ftrace_reset_array_ops(struct trace_array *tr)
 	tr->ops->func = ftrace_stub;
 }
 
-static inline void
+static nokprobe_inline void
 __ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip,
 		       struct ftrace_ops *ignored, struct pt_regs *regs)
 {
@@ -5309,11 +5312,13 @@ static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip,
 {
 	__ftrace_ops_list_func(ip, parent_ip, NULL, regs);
 }
+NOKPROBE_SYMBOL(ftrace_ops_list_func);
 #else
 static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip)
 {
 	__ftrace_ops_list_func(ip, parent_ip, NULL, NULL);
 }
+NOKPROBE_SYMBOL(ftrace_ops_no_ops);
 #endif
 
 /*
@@ -5343,6 +5348,7 @@ static void ftrace_ops_assist_func(unsigned long ip, unsigned long parent_ip,
 	preempt_enable_notrace();
 	trace_clear_recursion(bit);
 }
+NOKPROBE_SYMBOL(ftrace_ops_assist_func);
 
 /**
  * ftrace_ops_get_func - get the function a trampoline should call
@@ -5449,9 +5455,10 @@ static void *fpid_next(struct seq_file *m, void *v, loff_t *pos)
 	struct trace_array *tr = m->private;
 	struct trace_pid_list *pid_list = rcu_dereference_sched(tr->function_pids);
 
-	if (v == FTRACE_NO_PIDS)
+	if (v == FTRACE_NO_PIDS) {
+		(*pos)++;
 		return NULL;
-
+	}
 	return trace_pid_next(pid_list, v, pos);
 }
 
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index f316e90ad538..2cfe11e1190b 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -701,7 +701,7 @@ u64 ring_buffer_time_stamp(struct ring_buffer *buffer, int cpu)
 
 	preempt_disable_notrace();
 	time = rb_time_stamp(buffer);
-	preempt_enable_no_resched_notrace();
+	preempt_enable_notrace();
 
 	return time;
 }
@@ -4037,6 +4037,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_consume);
  * ring_buffer_read_prepare - Prepare for a non consuming read of the buffer
  * @buffer: The ring buffer to read from
  * @cpu: The cpu buffer to iterate over
+ * @flags: gfp flags to use for memory allocation
  *
  * This performs the initial preparations necessary to iterate
  * through the buffer.  Memory is allocated, buffer recording
@@ -4054,7 +4055,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_consume);
  * This overall must be paired with ring_buffer_read_finish.
  */
 struct ring_buffer_iter *
-ring_buffer_read_prepare(struct ring_buffer *buffer, int cpu)
+ring_buffer_read_prepare(struct ring_buffer *buffer, int cpu, gfp_t flags)
 {
 	struct ring_buffer_per_cpu *cpu_buffer;
 	struct ring_buffer_iter *iter;
@@ -4062,7 +4063,7 @@ ring_buffer_read_prepare(struct ring_buffer *buffer, int cpu)
 	if (!cpumask_test_cpu(cpu, buffer->cpumask))
 		return NULL;
 
-	iter = kmalloc(sizeof(*iter), GFP_KERNEL);
+	iter = kmalloc(sizeof(*iter), flags);
 	if (!iter)
 		return NULL;
 
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index f18dedf9195e..6a170a78b453 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -500,8 +500,10 @@ int trace_pid_write(struct trace_pid_list *filtered_pids,
 	 * not modified.
 	 */
 	pid_list = kmalloc(sizeof(*pid_list), GFP_KERNEL);
-	if (!pid_list)
+	if (!pid_list) {
+		trace_parser_put(&parser);
 		return -ENOMEM;
+	}
 
 	pid_list->pid_max = READ_ONCE(pid_max);
 
@@ -511,6 +513,7 @@ int trace_pid_write(struct trace_pid_list *filtered_pids,
 
 	pid_list->pids = vzalloc((pid_list->pid_max + 7) >> 3);
 	if (!pid_list->pids) {
+		trace_parser_put(&parser);
 		kfree(pid_list);
 		return -ENOMEM;
 	}
@@ -3449,7 +3452,8 @@ __tracing_open(struct inode *inode, struct file *file, bool snapshot)
 	if (iter->cpu_file == RING_BUFFER_ALL_CPUS) {
 		for_each_tracing_cpu(cpu) {
 			iter->buffer_iter[cpu] =
-				ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu);
+				ring_buffer_read_prepare(iter->trace_buffer->buffer,
+							 cpu, GFP_KERNEL);
 		}
 		ring_buffer_read_prepare_sync();
 		for_each_tracing_cpu(cpu) {
@@ -3459,7 +3463,8 @@ __tracing_open(struct inode *inode, struct file *file, bool snapshot)
 	} else {
 		cpu = iter->cpu_file;
 		iter->buffer_iter[cpu] =
-			ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu);
+			ring_buffer_read_prepare(iter->trace_buffer->buffer,
+						 cpu, GFP_KERNEL);
 		ring_buffer_read_prepare_sync();
 		ring_buffer_read_start(iter->buffer_iter[cpu]);
 		tracing_iter_reset(iter, cpu);
@@ -3695,9 +3700,14 @@ static int show_traces_open(struct inode *inode, struct file *file)
 	if (tracing_disabled)
 		return -ENODEV;
 
+	if (trace_array_get(tr) < 0)
+		return -ENODEV;
+
 	ret = seq_open(file, &show_traces_seq_ops);
-	if (ret)
+	if (ret) {
+		trace_array_put(tr);
 		return ret;
+	}
 
 	m = file->private_data;
 	m->private = tr;
@@ -3705,6 +3715,14 @@ static int show_traces_open(struct inode *inode, struct file *file)
 	return 0;
 }
 
+static int show_traces_release(struct inode *inode, struct file *file)
+{
+	struct trace_array *tr = inode->i_private;
+
+	trace_array_put(tr);
+	return seq_release(inode, file);
+}
+
 static ssize_t
 tracing_write_stub(struct file *filp, const char __user *ubuf,
 		   size_t count, loff_t *ppos)
@@ -3735,8 +3753,8 @@ static const struct file_operations tracing_fops = {
 static const struct file_operations show_traces_fops = {
 	.open		= show_traces_open,
 	.read		= seq_read,
-	.release	= seq_release,
 	.llseek		= seq_lseek,
+	.release	= show_traces_release,
 };
 
 static ssize_t
@@ -5199,6 +5217,7 @@ waitagain:
 	       sizeof(struct trace_iterator) -
 	       offsetof(struct trace_iterator, seq));
 	cpumask_clear(iter->started);
+	trace_seq_init(&iter->seq);
 	iter->pos = -1;
 
 	trace_event_read_lock();
@@ -5815,11 +5834,15 @@ tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt,
 			break;
 		}
 #endif
-		if (!tr->allocated_snapshot) {
+		if (!tr->allocated_snapshot)
+			ret = resize_buffer_duplicate_size(&tr->max_buffer,
+				&tr->trace_buffer, iter->cpu_file);
+		else
 			ret = alloc_snapshot(tr);
-			if (ret < 0)
-				break;
-		}
+
+		if (ret < 0)
+			break;
+
 		local_irq_disable();
 		/* Now, we're going to swap */
 		if (iter->cpu_file == RING_BUFFER_ALL_CPUS)
@@ -6140,12 +6163,16 @@ static void buffer_pipe_buf_release(struct pipe_inode_info *pipe,
 	buf->private = 0;
 }
 
-static void buffer_pipe_buf_get(struct pipe_inode_info *pipe,
+static bool buffer_pipe_buf_get(struct pipe_inode_info *pipe,
 				struct pipe_buffer *buf)
 {
 	struct buffer_ref *ref = (struct buffer_ref *)buf->private;
 
+	if (ref->ref > INT_MAX/2)
+		return false;
+
 	ref->ref++;
+	return true;
 }
 
 /* Pipe buffer operations for a buffer. */
@@ -7604,12 +7631,8 @@ void ftrace_dump(enum ftrace_dump_mode oops_dump_mode)
 
 		cnt++;
 
-		/* reset all but tr, trace, and overruns */
-		memset(&iter.seq, 0,
-		       sizeof(struct trace_iterator) -
-		       offsetof(struct trace_iterator, seq));
+		trace_iterator_reset(&iter);
 		iter.iter_flags |= TRACE_FILE_LAT_FMT;
-		iter.pos = -1;
 
 		if (trace_find_next_entry_inc(&iter) != NULL) {
 			int ret;
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index b0d8576c27ae..476c6c4204da 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -1673,4 +1673,22 @@ static inline void trace_event_enum_update(struct trace_enum_map **map, int len)
 
 extern struct trace_iterator *tracepoint_print_iter;
 
+/*
+ * Reset the state of the trace_iterator so that it can read consumed data.
+ * Normally, the trace_iterator is used for reading the data when it is not
+ * consumed, and must retain state.
+ */
+static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
+{
+	const size_t offset = offsetof(struct trace_iterator, seq);
+
+	/*
+	 * Keep gcc from complaining about overwriting more than just one
+	 * member in the structure.
+	 */
+	memset((char *)iter + offset, 0, sizeof(struct trace_iterator) - offset);
+
+	iter->pos = -1;
+}
+
 #endif /* _LINUX_KERNEL_TRACE_H */
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 9549ed120556..af969f753e5e 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -1310,9 +1310,6 @@ event_id_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos)
 	char buf[32];
 	int len;
 
-	if (*ppos)
-		return 0;
-
 	if (unlikely(!id))
 		return -ENODEV;
 
diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
index 7e6971ba9541..c9ca2ed50c0e 100644
--- a/kernel/trace/trace_events_trigger.c
+++ b/kernel/trace/trace_events_trigger.c
@@ -126,9 +126,10 @@ static void *trigger_next(struct seq_file *m, void *t, loff_t *pos)
 {
 	struct trace_event_file *event_file = event_file_data(m->private);
 
-	if (t == SHOW_AVAILABLE_TRIGGERS)
+	if (t == SHOW_AVAILABLE_TRIGGERS) {
+		(*pos)++;
 		return NULL;
-
+	}
 	return seq_list_next(t, &event_file->triggers, pos);
 }
 
@@ -1067,14 +1068,10 @@ register_snapshot_trigger(char *glob, struct event_trigger_ops *ops,
 			  struct event_trigger_data *data,
 			  struct trace_event_file *file)
 {
-	int ret = register_trigger(glob, ops, data, file);
-
-	if (ret > 0 && tracing_alloc_snapshot() != 0) {
-		unregister_trigger(glob, ops, data, file);
-		ret = 0;
-	}
+	if (tracing_alloc_snapshot() != 0)
+		return 0;
 
-	return ret;
+	return register_trigger(glob, ops, data, file);
 }
 
 static int
diff --git a/kernel/trace/trace_hwlat.c b/kernel/trace/trace_hwlat.c
index f00b0131c8f9..5fe23f0ee7db 100644
--- a/kernel/trace/trace_hwlat.c
+++ b/kernel/trace/trace_hwlat.c
@@ -151,7 +151,7 @@ void trace_hwlat_callback(bool enter)
 		if (enter)
 			nmi_ts_start = time_get();
 		else
-			nmi_total_ts = time_get() - nmi_ts_start;
+			nmi_total_ts += time_get() - nmi_ts_start;
 	}
 
 	if (enter)
@@ -257,6 +257,8 @@ static int get_sample(void)
 		/* Keep a running maximum ever recorded hardware latency */
 		if (sample > tr->max_latency)
 			tr->max_latency = sample;
+		if (outer_sample > tr->max_latency)
+			tr->max_latency = outer_sample;
 	}
 
 out:
diff --git a/kernel/trace/trace_kdb.c b/kernel/trace/trace_kdb.c
index 57149bce6aad..cf6337dc41f4 100644
--- a/kernel/trace/trace_kdb.c
+++ b/kernel/trace/trace_kdb.c
@@ -40,24 +40,22 @@ static void ftrace_dump_buf(int skip_lines, long cpu_file)
 
 	kdb_printf("Dumping ftrace buffer:\n");
 
-	/* reset all but tr, trace, and overruns */
-	memset(&iter.seq, 0,
-		   sizeof(struct trace_iterator) -
-		   offsetof(struct trace_iterator, seq));
+	trace_iterator_reset(&iter);
 	iter.iter_flags |= TRACE_FILE_LAT_FMT;
-	iter.pos = -1;
 
 	if (cpu_file == RING_BUFFER_ALL_CPUS) {
 		for_each_tracing_cpu(cpu) {
 			iter.buffer_iter[cpu] =
-			ring_buffer_read_prepare(iter.trace_buffer->buffer, cpu);
+			ring_buffer_read_prepare(iter.trace_buffer->buffer,
+						 cpu, GFP_ATOMIC);
 			ring_buffer_read_start(iter.buffer_iter[cpu]);
 			tracing_iter_reset(&iter, cpu);
 		}
 	} else {
 		iter.cpu_file = cpu_file;
 		iter.buffer_iter[cpu_file] =
-			ring_buffer_read_prepare(iter.trace_buffer->buffer, cpu_file);
+			ring_buffer_read_prepare(iter.trace_buffer->buffer,
+						 cpu_file, GFP_ATOMIC);
 		ring_buffer_read_start(iter.buffer_iter[cpu_file]);
 		tracing_iter_reset(&iter, cpu_file);
 	}
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index 9d4399b553a3..6403f45da9d5 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -625,7 +625,7 @@ static void start_wakeup_tracer(struct trace_array *tr)
 	if (ret) {
 		pr_info("wakeup trace: Couldn't activate tracepoint"
 			" probe to kernel_sched_migrate_task\n");
-		return;
+		goto fail_deprobe_sched_switch;
 	}
 
 	wakeup_reset(tr);
@@ -643,6 +643,8 @@ static void start_wakeup_tracer(struct trace_array *tr)
 		printk(KERN_ERR "failed to start wakeup tracer\n");
 
 	return;
+fail_deprobe_sched_switch:
+	unregister_trace_sched_switch(probe_wakeup_sched_switch, NULL);
 fail_deprobe_wake_new:
 	unregister_trace_sched_wakeup_new(probe_wakeup, NULL);
 fail_deprobe:
diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c
index 2a1abbaca10e..5d2c08efd12f 100644
--- a/kernel/trace/trace_stack.c
+++ b/kernel/trace/trace_stack.c
@@ -201,6 +201,11 @@ check_stack(unsigned long ip, unsigned long *stack)
 	local_irq_restore(flags);
 }
 
+/* Some archs may not define MCOUNT_INSN_SIZE */
+#ifndef MCOUNT_INSN_SIZE
+# define MCOUNT_INSN_SIZE 0
+#endif
+
 static void
 stack_trace_call(unsigned long ip, unsigned long parent_ip,
 		 struct ftrace_ops *op, struct pt_regs *pt_regs)
diff --git a/kernel/trace/trace_stat.c b/kernel/trace/trace_stat.c
index 413ff108fbd0..d19f2191960e 100644
--- a/kernel/trace/trace_stat.c
+++ b/kernel/trace/trace_stat.c
@@ -277,18 +277,22 @@ static int tracing_stat_init(void)
 
 	d_tracing = tracing_init_dentry();
 	if (IS_ERR(d_tracing))
-		return 0;
+		return -ENODEV;
 
 	stat_dir = tracefs_create_dir("trace_stat", d_tracing);
-	if (!stat_dir)
+	if (!stat_dir) {
 		pr_warn("Could not create tracefs 'trace_stat' entry\n");
+		return -ENOMEM;
+	}
 	return 0;
 }
 
 static int init_stat_file(struct stat_session *session)
 {
-	if (!stat_dir && tracing_stat_init())
-		return -ENODEV;
+	int ret;
+
+	if (!stat_dir && (ret = tracing_stat_init()))
+		return ret;
 
 	session->file = tracefs_create_file(session->ts->name, 0644,
 					    stat_dir,
@@ -301,7 +305,7 @@ static int init_stat_file(struct stat_session *session)
 int register_stat_tracer(struct tracer_stat *trace)
 {
 	struct stat_session *session, *node;
-	int ret;
+	int ret = -EINVAL;
 
 	if (!trace)
 		return -EINVAL;
@@ -312,17 +316,15 @@ int register_stat_tracer(struct tracer_stat *trace)
 	/* Already registered? */
 	mutex_lock(&all_stat_sessions_mutex);
 	list_for_each_entry(node, &all_stat_sessions, session_list) {
-		if (node->ts == trace) {
-			mutex_unlock(&all_stat_sessions_mutex);
-			return -EINVAL;
-		}
+		if (node->ts == trace)
+			goto out;
 	}
-	mutex_unlock(&all_stat_sessions_mutex);
 
+	ret = -ENOMEM;
 	/* Init the session */
 	session = kzalloc(sizeof(*session), GFP_KERNEL);
 	if (!session)
-		return -ENOMEM;
+		goto out;
 
 	session->ts = trace;
 	INIT_LIST_HEAD(&session->session_list);
@@ -331,15 +333,16 @@ int register_stat_tracer(struct tracer_stat *trace)
 	ret = init_stat_file(session);
 	if (ret) {
 		destroy_session(session);
-		return ret;
+		goto out;
 	}
 
+	ret = 0;
 	/* Register */
-	mutex_lock(&all_stat_sessions_mutex);
 	list_add_tail(&session->session_list, &all_stat_sessions);
+ out:
 	mutex_unlock(&all_stat_sessions_mutex);
 
-	return 0;
+	return ret;
 }
 
 void unregister_stat_tracer(struct tracer_stat *trace)
diff --git a/kernel/trace/tracing_map.c b/kernel/trace/tracing_map.c
index 305039b122fa..35b2ba07f3c6 100644
--- a/kernel/trace/tracing_map.c
+++ b/kernel/trace/tracing_map.c
@@ -90,8 +90,8 @@ static int tracing_map_cmp_atomic64(void *val_a, void *val_b)
 #define DEFINE_TRACING_MAP_CMP_FN(type)					\
 static int tracing_map_cmp_##type(void *val_a, void *val_b)		\
 {									\
-	type a = *(type *)val_a;					\
-	type b = *(type *)val_b;					\
+	type a = (type)(*(u64 *)val_a);					\
+	type b = (type)(*(u64 *)val_b);					\
 									\
 	return (a > b) ? 1 : ((a < b) ? -1 : 0);			\
 }
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 1961dd408bc5..00c295d3104b 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -1384,14 +1384,16 @@ static void __queue_work(int cpu, struct workqueue_struct *wq,
 	    WARN_ON_ONCE(!is_chained_work(wq)))
 		return;
 retry:
-	if (req_cpu == WORK_CPU_UNBOUND)
-		cpu = wq_select_unbound_cpu(raw_smp_processor_id());
-
 	/* pwq which will be used unless @work is executing elsewhere */
-	if (!(wq->flags & WQ_UNBOUND))
-		pwq = per_cpu_ptr(wq->cpu_pwqs, cpu);
-	else
+	if (wq->flags & WQ_UNBOUND) {
+		if (req_cpu == WORK_CPU_UNBOUND)
+			cpu = wq_select_unbound_cpu(raw_smp_processor_id());
 		pwq = unbound_pwq_by_node(wq, cpu_to_node(cpu));
+	} else {
+		if (req_cpu == WORK_CPU_UNBOUND)
+			cpu = raw_smp_processor_id();
+		pwq = per_cpu_ptr(wq->cpu_pwqs, cpu);
+	}
 
 	/*
 	 * If @work was previously on a different pool, it might still be
@@ -2344,8 +2346,14 @@ repeat:
 			 */
 			if (need_to_create_worker(pool)) {
 				spin_lock(&wq_mayday_lock);
-				get_pwq(pwq);
-				list_move_tail(&pwq->mayday_node, &wq->maydays);
+				/*
+				 * Queue iff we aren't racing destruction
+				 * and somebody else hasn't queued it already.
+				 */
+				if (wq->rescuer && list_empty(&pwq->mayday_node)) {
+					get_pwq(pwq);
+					list_add_tail(&pwq->mayday_node, &wq->maydays);
+				}
 				spin_unlock(&wq_mayday_lock);
 			}
 		}
@@ -4031,9 +4039,29 @@ void destroy_workqueue(struct workqueue_struct *wq)
 	struct pool_workqueue *pwq;
 	int node;
 
+	/*
+	 * Remove it from sysfs first so that sanity check failure doesn't
+	 * lead to sysfs name conflicts.
+	 */
+	workqueue_sysfs_unregister(wq);
+
 	/* drain it before proceeding with destruction */
 	drain_workqueue(wq);
 
+	/* kill rescuer, if sanity checks fail, leave it w/o rescuer */
+	if (wq->rescuer) {
+		struct worker *rescuer = wq->rescuer;
+
+		/* this prevents new queueing */
+		spin_lock_irq(&wq_mayday_lock);
+		wq->rescuer = NULL;
+		spin_unlock_irq(&wq_mayday_lock);
+
+		/* rescuer will empty maydays list before exiting */
+		kthread_stop(rescuer->task);
+		kfree(rescuer);
+	}
+
 	/* sanity checks */
 	mutex_lock(&wq->mutex);
 	for_each_pwq(pwq, wq) {
@@ -4063,11 +4091,6 @@ void destroy_workqueue(struct workqueue_struct *wq)
 	list_del_rcu(&wq->list);
 	mutex_unlock(&wq_pool_mutex);
 
-	workqueue_sysfs_unregister(wq);
-
-	if (wq->rescuer)
-		kthread_stop(wq->rescuer->task);
-
 	if (!(wq->flags & WQ_UNBOUND)) {
 		/*
 		 * The base ref is never dropped on per-cpu pwqs.  Directly
@@ -4344,7 +4367,8 @@ static void show_pwq(struct pool_workqueue *pwq)
 	pr_info("  pwq %d:", pool->id);
 	pr_cont_pool_info(pool);
 
-	pr_cont(" active=%d/%d%s\n", pwq->nr_active, pwq->max_active,
+	pr_cont(" active=%d/%d refcnt=%d%s\n",
+		pwq->nr_active, pwq->max_active, pwq->refcnt,
 		!list_empty(&pwq->mayday_node) ? " MAYDAY" : "");
 
 	hash_for_each(pool->busy_hash, bkt, worker, hentry) {