Merge branch 'x86-microcode-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86/microcode changes from Ingo Molnar:
 "The biggest changes are to AMD microcode patching: add code for
  caching all microcode patches which belong to the current family on
  which we're running, in the kernel.

  We look up the patch needed for each core from the cache at
  patch-application time instead of holding a single patch per-system"

* 'x86-microcode-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, microcode, AMD: Fix use after free in free_cache()
  x86, microcode, AMD: Rewrite patch application procedure
  x86, microcode, AMD: Add a small, per-family patches cache
  x86, microcode, AMD: Add reverse equiv table search
  x86, microcode: Add a refresh firmware flag to ->request_microcode_fw
  x86, microcode, AMD: Read CPUID(1).EAX on the correct cpu
  x86, microcode, AMD: Check before applying a patch
  x86, microcode, AMD: Remove useless get_ucode_data wrapper
  x86, microcode: Straighten out Kconfig text
  x86, microcode: Cleanup cpu hotplug notifier callback
  x86, microcode: Drop uci->mc check on resume path
  x86, microcode: Save an indentation level in reload_for_cpu

3 files changed, 261 insertions, 166 deletions

diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index 82746f942cd8..7720ff5a9ee2 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -75,20 +75,113 @@ struct microcode_amd {
 
 static struct equiv_cpu_entry *equiv_cpu_table;
 
-/* page-sized ucode patch buffer */
-void *patch;
+struct ucode_patch {
+	struct list_head plist;
+	void *data;
+	u32 patch_id;
+	u16 equiv_cpu;
+};
+
+static LIST_HEAD(pcache);
+
+static u16 find_equiv_id(unsigned int cpu)
+{
+	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+	int i = 0;
+
+	if (!equiv_cpu_table)
+		return 0;
+
+	while (equiv_cpu_table[i].installed_cpu != 0) {
+		if (uci->cpu_sig.sig == equiv_cpu_table[i].installed_cpu)
+			return equiv_cpu_table[i].equiv_cpu;
+
+		i++;
+	}
+	return 0;
+}
+
+static u32 find_cpu_family_by_equiv_cpu(u16 equiv_cpu)
+{
+	int i = 0;
+
+	BUG_ON(!equiv_cpu_table);
+
+	while (equiv_cpu_table[i].equiv_cpu != 0) {
+		if (equiv_cpu == equiv_cpu_table[i].equiv_cpu)
+			return equiv_cpu_table[i].installed_cpu;
+		i++;
+	}
+	return 0;
+}
+
+/*
+ * a small, trivial cache of per-family ucode patches
+ */
+static struct ucode_patch *cache_find_patch(u16 equiv_cpu)
+{
+	struct ucode_patch *p;
+
+	list_for_each_entry(p, &pcache, plist)
+		if (p->equiv_cpu == equiv_cpu)
+			return p;
+	return NULL;
+}
+
+static void update_cache(struct ucode_patch *new_patch)
+{
+	struct ucode_patch *p;
+
+	list_for_each_entry(p, &pcache, plist) {
+		if (p->equiv_cpu == new_patch->equiv_cpu) {
+			if (p->patch_id >= new_patch->patch_id)
+				/* we already have the latest patch */
+				return;
+
+			list_replace(&p->plist, &new_patch->plist);
+			kfree(p->data);
+			kfree(p);
+			return;
+		}
+	}
+	/* no patch found, add it */
+	list_add_tail(&new_patch->plist, &pcache);
+}
+
+static void free_cache(void)
+{
+	struct ucode_patch *p, *tmp;
+
+	list_for_each_entry_safe(p, tmp, &pcache, plist) {
+		__list_del(p->plist.prev, p->plist.next);
+		kfree(p->data);
+		kfree(p);
+	}
+}
+
+static struct ucode_patch *find_patch(unsigned int cpu)
+{
+	u16 equiv_id;
+
+	equiv_id = find_equiv_id(cpu);
+	if (!equiv_id)
+		return NULL;
+
+	return cache_find_patch(equiv_id);
+}
 
 static int collect_cpu_info_amd(int cpu, struct cpu_signature *csig)
 {
 	struct cpuinfo_x86 *c = &cpu_data(cpu);
 
+	csig->sig = cpuid_eax(0x00000001);
 	csig->rev = c->microcode;
 	pr_info("CPU%d: patch_level=0x%08x\n", cpu, csig->rev);
 
 	return 0;
 }
 
-static unsigned int verify_ucode_size(int cpu, u32 patch_size,
+static unsigned int verify_patch_size(int cpu, u32 patch_size,
 				      unsigned int size)
 {
 	struct cpuinfo_x86 *c = &cpu_data(cpu);
@@ -118,95 +211,37 @@ static unsigned int verify_ucode_size(int cpu, u32 patch_size,
 	return patch_size;
 }
 
-static u16 find_equiv_id(void)
+static int apply_microcode_amd(int cpu)
 {
-	unsigned int current_cpu_id, i = 0;
-
-	BUG_ON(equiv_cpu_table == NULL);
-
-	current_cpu_id = cpuid_eax(0x00000001);
-
-	while (equiv_cpu_table[i].installed_cpu != 0) {
-		if (current_cpu_id == equiv_cpu_table[i].installed_cpu)
-			return equiv_cpu_table[i].equiv_cpu;
-
-		i++;
-	}
-	return 0;
-}
+	struct cpuinfo_x86 *c = &cpu_data(cpu);
+	struct microcode_amd *mc_amd;
+	struct ucode_cpu_info *uci;
+	struct ucode_patch *p;
+	u32 rev, dummy;
 
-/*
- * we signal a good patch is found by returning its size > 0
- */
-static int get_matching_microcode(int cpu, const u8 *ucode_ptr,
-				  unsigned int leftover_size, int rev,
-				  unsigned int *current_size)
-{
-	struct microcode_header_amd *mc_hdr;
-	unsigned int actual_size, patch_size;
-	u16 equiv_cpu_id;
+	BUG_ON(raw_smp_processor_id() != cpu);
 
-	/* size of the current patch we're staring at */
-	patch_size = *(u32 *)(ucode_ptr + 4);
-	*current_size = patch_size + SECTION_HDR_SIZE;
+	uci = ucode_cpu_info + cpu;
 
-	equiv_cpu_id = find_equiv_id();
-	if (!equiv_cpu_id)
+	p = find_patch(cpu);
+	if (!p)
 		return 0;
 
-	/*
-	 * let's look at the patch header itself now
-	 */
-	mc_hdr = (struct microcode_header_amd *)(ucode_ptr + SECTION_HDR_SIZE);
+	mc_amd  = p->data;
+	uci->mc = p->data;
 
-	if (mc_hdr->processor_rev_id != equiv_cpu_id)
-		return 0;
+	rdmsr(MSR_AMD64_PATCH_LEVEL, rev, dummy);
 
-	/* ucode might be chipset specific -- currently we don't support this */
-	if (mc_hdr->nb_dev_id || mc_hdr->sb_dev_id) {
-		pr_err("CPU%d: chipset specific code not yet supported\n",
-		       cpu);
+	/* need to apply patch? */
+	if (rev >= mc_amd->hdr.patch_id) {
+		c->microcode = rev;
 		return 0;
 	}
 
-	if (mc_hdr->patch_id <= rev)
-		return 0;
-
-	/*
-	 * now that the header looks sane, verify its size
-	 */
-	actual_size = verify_ucode_size(cpu, patch_size, leftover_size);
-	if (!actual_size)
-		return 0;
-
-	/* clear the patch buffer */
-	memset(patch, 0, PAGE_SIZE);
-
-	/* all looks ok, get the binary patch */
-	get_ucode_data(patch, ucode_ptr + SECTION_HDR_SIZE, actual_size);
-
-	return actual_size;
-}
-
-static int apply_microcode_amd(int cpu)
-{
-	u32 rev, dummy;
-	int cpu_num = raw_smp_processor_id();
-	struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
-	struct microcode_amd *mc_amd = uci->mc;
-	struct cpuinfo_x86 *c = &cpu_data(cpu);
-
-	/* We should bind the task to the CPU */
-	BUG_ON(cpu_num != cpu);
-
-	if (mc_amd == NULL)
-		return 0;
-
 	wrmsrl(MSR_AMD64_PATCH_LOADER, (u64)(long)&mc_amd->hdr.data_code);
-	/* get patch id after patching */
-	rdmsr(MSR_AMD64_PATCH_LEVEL, rev, dummy);
 
-	/* check current patch id and patch's id for match */
+	/* verify patch application was successful */
+	rdmsr(MSR_AMD64_PATCH_LEVEL, rev, dummy);
 	if (rev != mc_amd->hdr.patch_id) {
 		pr_err("CPU%d: update failed for patch_level=0x%08x\n",
 		       cpu, mc_amd->hdr.patch_id);
@@ -238,7 +273,7 @@ static int install_equiv_cpu_table(const u8 *buf)
 		return -ENOMEM;
 	}
 
-	get_ucode_data(equiv_cpu_table, buf + CONTAINER_HDR_SZ, size);
+	memcpy(equiv_cpu_table, buf + CONTAINER_HDR_SZ, size);
 
 	/* add header length */
 	return size + CONTAINER_HDR_SZ;
@@ -250,61 +285,113 @@ static void free_equiv_cpu_table(void)
 	equiv_cpu_table = NULL;
 }
 
-static enum ucode_state
-generic_load_microcode(int cpu, const u8 *data, size_t size)
+static void cleanup(void)
 {
-	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
-	struct microcode_header_amd *mc_hdr = NULL;
-	unsigned int mc_size, leftover, current_size = 0;
+	free_equiv_cpu_table();
+	free_cache();
+}
+
+/*
+ * We return the current size even if some of the checks failed so that
+ * we can skip over the next patch. If we return a negative value, we
+ * signal a grave error like a memory allocation has failed and the
+ * driver cannot continue functioning normally. In such cases, we tear
+ * down everything we've used up so far and exit.
+ */
+static int verify_and_add_patch(unsigned int cpu, u8 *fw, unsigned int leftover)
+{
+	struct cpuinfo_x86 *c = &cpu_data(cpu);
+	struct microcode_header_amd *mc_hdr;
+	struct ucode_patch *patch;
+	unsigned int patch_size, crnt_size, ret;
+	u32 proc_fam;
+	u16 proc_id;
+
+	patch_size  = *(u32 *)(fw + 4);
+	crnt_size   = patch_size + SECTION_HDR_SIZE;
+	mc_hdr	    = (struct microcode_header_amd *)(fw + SECTION_HDR_SIZE);
+	proc_id	    = mc_hdr->processor_rev_id;
+
+	proc_fam = find_cpu_family_by_equiv_cpu(proc_id);
+	if (!proc_fam) {
+		pr_err("No patch family for equiv ID: 0x%04x\n", proc_id);
+		return crnt_size;
+	}
+
+	/* check if patch is for the current family */
+	proc_fam = ((proc_fam >> 8) & 0xf) + ((proc_fam >> 20) & 0xff);
+	if (proc_fam != c->x86)
+		return crnt_size;
+
+	if (mc_hdr->nb_dev_id || mc_hdr->sb_dev_id) {
+		pr_err("Patch-ID 0x%08x: chipset-specific code unsupported.\n",
+			mc_hdr->patch_id);
+		return crnt_size;
+	}
+
+	ret = verify_patch_size(cpu, patch_size, leftover);
+	if (!ret) {
+		pr_err("Patch-ID 0x%08x: size mismatch.\n", mc_hdr->patch_id);
+		return crnt_size;
+	}
+
+	patch = kzalloc(sizeof(*patch), GFP_KERNEL);
+	if (!patch) {
+		pr_err("Patch allocation failure.\n");
+		return -EINVAL;
+	}
+
+	patch->data = kzalloc(patch_size, GFP_KERNEL);
+	if (!patch->data) {
+		pr_err("Patch data allocation failure.\n");
+		kfree(patch);
+		return -EINVAL;
+	}
+
+	/* All looks ok, copy patch... */
+	memcpy(patch->data, fw + SECTION_HDR_SIZE, patch_size);
+	INIT_LIST_HEAD(&patch->plist);
+	patch->patch_id  = mc_hdr->patch_id;
+	patch->equiv_cpu = proc_id;
+
+	/* ... and add to cache. */
+	update_cache(patch);
+
+	return crnt_size;
+}
+
+static enum ucode_state load_microcode_amd(int cpu, const u8 *data, size_t size)
+{
+	enum ucode_state ret = UCODE_ERROR;
+	unsigned int leftover;
+	u8 *fw = (u8 *)data;
+	int crnt_size = 0;
 	int offset;
-	const u8 *ucode_ptr = data;
-	void *new_mc = NULL;
-	unsigned int new_rev = uci->cpu_sig.rev;
-	enum ucode_state state = UCODE_ERROR;
 
-	offset = install_equiv_cpu_table(ucode_ptr);
+	offset = install_equiv_cpu_table(data);
 	if (offset < 0) {
 		pr_err("failed to create equivalent cpu table\n");
-		goto out;
+		return ret;
 	}
-	ucode_ptr += offset;
+	fw += offset;
 	leftover = size - offset;
 
-	if (*(u32 *)ucode_ptr != UCODE_UCODE_TYPE) {
+	if (*(u32 *)fw != UCODE_UCODE_TYPE) {
 		pr_err("invalid type field in container file section header\n");
-		goto free_table;
+		free_equiv_cpu_table();
+		return ret;
 	}
 
 	while (leftover) {
-		mc_size = get_matching_microcode(cpu, ucode_ptr, leftover,
-						 new_rev, &current_size);
-		if (mc_size) {
-			mc_hdr  = patch;
-			new_mc  = patch;
-			new_rev = mc_hdr->patch_id;
-			goto out_ok;
-		}
-
-		ucode_ptr += current_size;
-		leftover  -= current_size;
-	}
+		crnt_size = verify_and_add_patch(cpu, fw, leftover);
+		if (crnt_size < 0)
+			return ret;
 
-	if (!new_mc) {
-		state = UCODE_NFOUND;
-		goto free_table;
+		fw	 += crnt_size;
+		leftover -= crnt_size;
 	}
 
-out_ok:
-	uci->mc = new_mc;
-	state = UCODE_OK;
-	pr_debug("CPU%d update ucode (0x%08x -> 0x%08x)\n",
-		 cpu, uci->cpu_sig.rev, new_rev);
-
-free_table:
-	free_equiv_cpu_table();
-
-out:
-	return state;
+	return UCODE_OK;
 }
 
 /*
@@ -315,7 +402,7 @@ out:
  *
  * This legacy file is always smaller than 2K in size.
  *
- * Starting at family 15h they are in family specific firmware files:
+ * Beginning with family 15h, they are in family-specific firmware files:
  *
  *    amd-ucode/microcode_amd_fam15h.bin
  *    amd-ucode/microcode_amd_fam16h.bin
@@ -323,12 +410,17 @@ out:
  *
  * These might be larger than 2K.
  */
-static enum ucode_state request_microcode_amd(int cpu, struct device *device)
+static enum ucode_state request_microcode_amd(int cpu, struct device *device,
+					      bool refresh_fw)
 {
 	char fw_name[36] = "amd-ucode/microcode_amd.bin";
-	const struct firmware *fw;
-	enum ucode_state ret = UCODE_NFOUND;
 	struct cpuinfo_x86 *c = &cpu_data(cpu);
+	enum ucode_state ret = UCODE_NFOUND;
+	const struct firmware *fw;
+
+	/* reload ucode container only on the boot cpu */
+	if (!refresh_fw || c->cpu_index != boot_cpu_data.cpu_index)
+		return UCODE_OK;
 
 	if (c->x86 >= 0x15)
 		snprintf(fw_name, sizeof(fw_name), "amd-ucode/microcode_amd_fam%.2xh.bin", c->x86);
@@ -344,12 +436,17 @@ static enum ucode_state request_microcode_amd(int cpu, struct device *device)
 		goto fw_release;
 	}
 
-	ret = generic_load_microcode(cpu, fw->data, fw->size);
+	/* free old equiv table */
+	free_equiv_cpu_table();
+
+	ret = load_microcode_amd(cpu, fw->data, fw->size);
+	if (ret != UCODE_OK)
+		cleanup();
 
-fw_release:
+ fw_release:
 	release_firmware(fw);
 
-out:
+ out:
 	return ret;
 }
 
@@ -383,14 +480,10 @@ struct microcode_ops * __init init_amd_microcode(void)
 		return NULL;
 	}
 
-	patch = (void *)get_zeroed_page(GFP_KERNEL);
-	if (!patch)
-		return NULL;
-
 	return &microcode_amd_ops;
 }
 
 void __exit exit_amd_microcode(void)
 {
-	free_page((unsigned long)patch);
+	cleanup();
 }
diff --git a/arch/x86/kernel/microcode_core.c b/arch/x86/kernel/microcode_core.c
index 9e5bcf1e2376..3a04b224d0c0 100644
--- a/arch/x86/kernel/microcode_core.c
+++ b/arch/x86/kernel/microcode_core.c
@@ -279,19 +279,18 @@ static struct platform_device	*microcode_pdev;
 static int reload_for_cpu(int cpu)
 {
 	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+	enum ucode_state ustate;
 	int err = 0;
 
-	if (uci->valid) {
-		enum ucode_state ustate;
-
-		ustate = microcode_ops->request_microcode_fw(cpu, &microcode_pdev->dev);
-		if (ustate == UCODE_OK)
-			apply_microcode_on_target(cpu);
-		else
-			if (ustate == UCODE_ERROR)
-				err = -EINVAL;
-	}
+	if (!uci->valid)
+		return err;
 
+	ustate = microcode_ops->request_microcode_fw(cpu, &microcode_pdev->dev, true);
+	if (ustate == UCODE_OK)
+		apply_microcode_on_target(cpu);
+	else
+		if (ustate == UCODE_ERROR)
+			err = -EINVAL;
 	return err;
 }
 
@@ -373,18 +372,15 @@ static void microcode_fini_cpu(int cpu)
 
 static enum ucode_state microcode_resume_cpu(int cpu)
 {
-	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
-
-	if (!uci->mc)
-		return UCODE_NFOUND;
-
 	pr_debug("CPU%d updated upon resume\n", cpu);
-	apply_microcode_on_target(cpu);
+
+	if (apply_microcode_on_target(cpu))
+		return UCODE_ERROR;
 
 	return UCODE_OK;
 }
 
-static enum ucode_state microcode_init_cpu(int cpu)
+static enum ucode_state microcode_init_cpu(int cpu, bool refresh_fw)
 {
 	enum ucode_state ustate;
 
@@ -395,7 +391,8 @@ static enum ucode_state microcode_init_cpu(int cpu)
 	if (system_state != SYSTEM_RUNNING)
 		return UCODE_NFOUND;
 
-	ustate = microcode_ops->request_microcode_fw(cpu, &microcode_pdev->dev);
+	ustate = microcode_ops->request_microcode_fw(cpu, &microcode_pdev->dev,
+						     refresh_fw);
 
 	if (ustate == UCODE_OK) {
 		pr_debug("CPU%d updated upon init\n", cpu);
@@ -408,14 +405,11 @@ static enum ucode_state microcode_init_cpu(int cpu)
 static enum ucode_state microcode_update_cpu(int cpu)
 {
 	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
-	enum ucode_state ustate;
 
 	if (uci->valid)
-		ustate = microcode_resume_cpu(cpu);
-	else
-		ustate = microcode_init_cpu(cpu);
+		return microcode_resume_cpu(cpu);
 
-	return ustate;
+	return microcode_init_cpu(cpu, false);
 }
 
 static int mc_device_add(struct device *dev, struct subsys_interface *sif)
@@ -431,7 +425,7 @@ static int mc_device_add(struct device *dev, struct subsys_interface *sif)
 	if (err)
 		return err;
 
-	if (microcode_init_cpu(cpu) == UCODE_ERROR)
+	if (microcode_init_cpu(cpu, true) == UCODE_ERROR)
 		return -EINVAL;
 
 	return err;
@@ -480,34 +474,41 @@ mc_cpu_callback(struct notifier_block *nb, unsigned long action, void *hcpu)
 	struct device *dev;
 
 	dev = get_cpu_device(cpu);
-	switch (action) {
+
+	switch (action & ~CPU_TASKS_FROZEN) {
 	case CPU_ONLINE:
-	case CPU_ONLINE_FROZEN:
 		microcode_update_cpu(cpu);
-	case CPU_DOWN_FAILED:
-	case CPU_DOWN_FAILED_FROZEN:
 		pr_debug("CPU%d added\n", cpu);
+		/*
+		 * "break" is missing on purpose here because we want to fall
+		 * through in order to create the sysfs group.
+		 */
+
+	case CPU_DOWN_FAILED:
 		if (sysfs_create_group(&dev->kobj, &mc_attr_group))
 			pr_err("Failed to create group for CPU%d\n", cpu);
 		break;
+
 	case CPU_DOWN_PREPARE:
-	case CPU_DOWN_PREPARE_FROZEN:
 		/* Suspend is in progress, only remove the interface */
 		sysfs_remove_group(&dev->kobj, &mc_attr_group);
 		pr_debug("CPU%d removed\n", cpu);
 		break;
 
 	/*
+	 * case CPU_DEAD:
+	 *
 	 * When a CPU goes offline, don't free up or invalidate the copy of
 	 * the microcode in kernel memory, so that we can reuse it when the
 	 * CPU comes back online without unnecessarily requesting the userspace
 	 * for it again.
 	 */
-	case CPU_UP_CANCELED_FROZEN:
-		/* The CPU refused to come up during a system resume */
-		microcode_fini_cpu(cpu);
-		break;
 	}
+
+	/* The CPU refused to come up during a system resume */
+	if (action == CPU_UP_CANCELED_FROZEN)
+		microcode_fini_cpu(cpu);
+
 	return NOTIFY_OK;
 }
 
diff --git a/arch/x86/kernel/microcode_intel.c b/arch/x86/kernel/microcode_intel.c
index 0327e2b3c408..3544aed39338 100644
--- a/arch/x86/kernel/microcode_intel.c
+++ b/arch/x86/kernel/microcode_intel.c
@@ -405,7 +405,8 @@ static int get_ucode_fw(void *to, const void *from, size_t n)
 	return 0;
 }
 
-static enum ucode_state request_microcode_fw(int cpu, struct device *device)
+static enum ucode_state request_microcode_fw(int cpu, struct device *device,
+					     bool refresh_fw)
 {
 	char name[30];
 	struct cpuinfo_x86 *c = &cpu_data(cpu);