Merge branch 'android-4.4-p' of https://android.googlesource.com/kernel/common into lineage-17.1-caf-msm8998

This brings LA.UM.8.4.r1-05200-8x98.0 up to date with
https://android.googlesource.com/kernel/common/ android-4.4-p at commit:
4db1ebdd40ec0 FROMLIST: HID: nintendo: add nintendo switch controller driver

Conflicts:
	arch/arm64/boot/Makefile
	arch/arm64/kernel/psci.c
	arch/x86/configs/x86_64_cuttlefish_defconfig
	drivers/md/dm.c
	drivers/of/Kconfig
	drivers/thermal/thermal_core.c
	fs/proc/meminfo.c
	kernel/locking/spinlock_debug.c
	kernel/time/hrtimer.c
	net/wireless/util.c

Change-Id: I5b5163497b7c6ab8487ffbb2d036e4cda01ed670

2 files changed, 16 insertions, 40 deletions

diff --git a/fs/proc/array.c b/fs/proc/array.c
index 015cdc615dfb..d4b1c2361adf 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -425,9 +425,21 @@ static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
 	mm = get_task_mm(task);
 	if (mm) {
 		vsize = task_vsize(mm);
-		if (permitted) {
-			eip = KSTK_EIP(task);
-			esp = KSTK_ESP(task);
+		/*
+		 * esp and eip are intentionally zeroed out.  There is no
+		 * non-racy way to read them without freezing the task.
+		 * Programs that need reliable values can use ptrace(2).
+		 *
+		 * The only exception is if the task is core dumping because
+		 * a program is not able to use ptrace(2) in that case. It is
+		 * safe because the task has stopped executing permanently.
+		 */
+		if (permitted && (task->flags & (PF_EXITING|PF_DUMPCORE))) {
+			if (try_get_task_stack(task)) {
+				eip = KSTK_EIP(task);
+				esp = KSTK_ESP(task);
+				put_task_stack(task);
+			}
 		}
 	}
 
diff --git a/fs/proc/meminfo.c b/fs/proc/meminfo.c
index 5e5c443591ea..83720460c5bc 100644
--- a/fs/proc/meminfo.c
+++ b/fs/proc/meminfo.c
@@ -29,10 +29,7 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
 	unsigned long committed;
 	long cached;
 	long available;
-	unsigned long pagecache;
-	unsigned long wmark_low = 0;
 	unsigned long pages[NR_LRU_LISTS];
-	struct zone *zone;
 	int lru;
 
 /*
@@ -51,40 +48,7 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
 	for (lru = LRU_BASE; lru < NR_LRU_LISTS; lru++)
 		pages[lru] = global_page_state(NR_LRU_BASE + lru);
 
-	for_each_zone(zone)
-		wmark_low += zone->watermark[WMARK_LOW];
-
-	/*
-	 * Estimate the amount of memory available for userspace allocations,
-	 * without causing swapping.
-	 */
-	available = i.freeram - totalreserve_pages;
-
-	/*
-	 * Not all the page cache can be freed, otherwise the system will
-	 * start swapping. Assume at least half of the page cache, or the
-	 * low watermark worth of cache, needs to stay.
-	 */
-	pagecache = pages[LRU_ACTIVE_FILE] + pages[LRU_INACTIVE_FILE];
-	pagecache -= min(pagecache / 2, wmark_low);
-	available += pagecache;
-
-	/*
-	 * Part of the reclaimable slab consists of items that are in use,
-	 * and cannot be freed. Cap this estimate at the low watermark.
-	 */
-	available += global_page_state(NR_SLAB_RECLAIMABLE) -
-		     min(global_page_state(NR_SLAB_RECLAIMABLE) / 2, wmark_low);
-
-	/*
-	 * Part of the kernel memory, which can be released under memory
-	 * pressure.
-	 */
-	available += global_page_state(NR_INDIRECTLY_RECLAIMABLE_BYTES) >>
-		PAGE_SHIFT;
-
-	if (available < 0)
-		available = 0;
+	available = si_mem_available();
 
 	/*
 	 * Tagged format, for easy grepping and expansion.