Merge tag 'v4.1.7' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable into linux-linaro-lsk-v4.1lsk-v4.1-15.09

This is the 4.1.7 stable release

* tag 'v4.1.7' of git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable: (165 commits)
  Linux 4.1.7
  ARM: 8405/1: VDSO: fix regression with toolchains lacking ld.bfd executable
  x86/idle: Restore trace_cpu_idle to mwait_idle() calls
  x86/apic: Fix fallout from x2apic cleanup
  x86/xen: make CONFIG_XEN depend on CONFIG_X86_LOCAL_APIC
  arm64: perf: fix unassigned cpu_pmu->plat_device when probing PMU PPIs
  arm64: KVM: Fix host crash when injecting a fault into a 32bit guest
  fnic: Use the local variable instead of I/O flag to acquire io_req_lock in fnic_queuecommand() to avoid deadloack
  Add factory recertified Crucial M500s to blacklist
  can: pcan_usb: don't provide CAN FD bittimings by non-FD adapters
  SCSI: Fix NULL pointer dereference in runtime PM
  genirq: Introduce irq_chip_set_type_parent() helper
  genirq: Don't return ENOSYS in irq_chip_retrigger_hierarchy
  ARM: OMAP: wakeupgen: Restore the irq_set_type() mechanism
  irqchip/crossbar: Restore set_wake functionality
  irqchip/crossbar: Restore the mask on suspend behaviour
  irqchip/crossbar: Restore the irq_set_type() mechanism
  9p: ensure err is initialized to 0 in p9_client_read/write
  drm/i915: Avoid TP3 on CHV
  drm/i915: remove HBR2 from chv supported list
  ...

1 files changed, 5 insertions, 9 deletions

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 5e8eadd71bac..0d024fc8aa8e 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -937,21 +937,17 @@ static unsigned long shrink_page_list(struct list_head *page_list,
 		 *
 		 * 2) Global reclaim encounters a page, memcg encounters a
 		 *    page that is not marked for immediate reclaim or
-		 *    the caller does not have __GFP_IO. In this case mark
+		 *    the caller does not have __GFP_FS (or __GFP_IO if it's
+		 *    simply going to swap, not to fs). In this case mark
 		 *    the page for immediate reclaim and continue scanning.
 		 *
-		 *    __GFP_IO is checked  because a loop driver thread might
+		 *    Require may_enter_fs because we would wait on fs, which
+		 *    may not have submitted IO yet. And the loop driver might
 		 *    enter reclaim, and deadlock if it waits on a page for
 		 *    which it is needed to do the write (loop masks off
 		 *    __GFP_IO|__GFP_FS for this reason); but more thought
 		 *    would probably show more reasons.
 		 *
-		 *    Don't require __GFP_FS, since we're not going into the
-		 *    FS, just waiting on its writeback completion. Worryingly,
-		 *    ext4 gfs2 and xfs allocate pages with
-		 *    grab_cache_page_write_begin(,,AOP_FLAG_NOFS), so testing
-		 *    may_enter_fs here is liable to OOM on them.
-		 *
 		 * 3) memcg encounters a page that is not already marked
 		 *    PageReclaim. memcg does not have any dirty pages
 		 *    throttling so we could easily OOM just because too many
@@ -968,7 +964,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
 
 			/* Case 2 above */
 			} else if (global_reclaim(sc) ||
-			    !PageReclaim(page) || !(sc->gfp_mask & __GFP_IO)) {
+			    !PageReclaim(page) || !may_enter_fs) {
 				/*
 				 * This is slightly racy - end_page_writeback()
 				 * might have just cleared PageReclaim, then