Merge tag 'v4.1.33' into 4.1-2.0.x-imx

Linux 4.1.33

* tag 'v4.1.33': (1760 commits)
  Linux 4.1.33
  Revert "ARC: mm: don't loose PTE_SPECIAL in pte_modify()"
  x86/AMD: Apply erratum 665 on machines without a BIOS fix
  x86/paravirt: Do not trace _paravirt_ident_*() functions
  ovl: listxattr: use strnlen()
  ovl: remove posix_acl_default from workdir
  serial: 8250: added acces i/o products quad and octal serial cards
  sysfs: correctly handle read offset on PREALLOC attrs
  sysfs: correctly handle short reads on PREALLOC attrs.
  kernfs: don't depend on d_find_any_alias() when generating notifications
  dm crypt: fix free of bad values after tfm allocation failure
  dm crypt: fix error with too large bios
  dm log writes: fix check of kthread_run() return value
  dm log writes: fix bug with too large bios
  dm log writes: move IO accounting earlier to fix error path
  NFSv4.x: Fix a refcount leak in nfs_callback_up_net
  xfs: prevent dropping ioend completions during buftarg wait
  xfs: fix superblock inprogress check
  USB: serial: option: add WeTelecom 0x6802 and 0x6803 products
  USB: avoid left shift by -1
  ...

Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>

1 files changed, 12 insertions, 5 deletions

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 68dea90334cb..221762e24a68 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3824,16 +3824,17 @@ static void __mem_cgroup_usage_unregister_event(struct mem_cgroup *memcg,
 swap_buffers:
 	/* Swap primary and spare array */
 	thresholds->spare = thresholds->primary;
-	/* If all events are unregistered, free the spare array */
-	if (!new) {
-		kfree(thresholds->spare);
-		thresholds->spare = NULL;
-	}
 
 	rcu_assign_pointer(thresholds->primary, new);
 
 	/* To be sure that nobody uses thresholds */
 	synchronize_rcu();
+
+	/* If all events are unregistered, free the spare array */
+	if (!new) {
+		kfree(thresholds->spare);
+		thresholds->spare = NULL;
+	}
 unlock:
 	mutex_unlock(&memcg->thresholds_lock);
 }
@@ -5288,6 +5289,7 @@ static ssize_t memory_high_write(struct kernfs_open_file *of,
 				 char *buf, size_t nbytes, loff_t off)
 {
 	struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));
+	unsigned long nr_pages;
 	unsigned long high;
 	int err;
 
@@ -5298,6 +5300,11 @@ static ssize_t memory_high_write(struct kernfs_open_file *of,
 
 	memcg->high = high;
 
+	nr_pages = page_counter_read(&memcg->memory);
+	if (nr_pages > high)
+		try_to_free_mem_cgroup_pages(memcg, nr_pages - high,
+					     GFP_KERNEL, true);
+
 	return nbytes;
 }