From 2515b5c1b63a5f7425610eb514f29f556f081d96 Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Mon, 23 May 2016 16:26:11 -0700 Subject: [PATCH] drm/i915: make i915_gem_mmap_ioctl wait for mmap_sem killable i915_gem_mmap_ioctl relies on mmap_sem for write. If the waiting task gets killed by the oom killer it would block oom_reaper from asynchronous address space reclaim and reduce the chances of timely OOM resolving. Wait for the lock in the killable mode and return with EINTR if the task got killed while waiting. Signed-off-by: Michal Hocko Acked-by: Vlastimil Babka Cc: Daniel Vetter Cc: David Airlie Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/gpu/drm/i915/i915_gem.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 233adc31ef0c9..ddd1d78c346f3 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -1754,7 +1754,10 @@ i915_gem_mmap_ioctl(struct drm_device *dev, void *data, struct mm_struct *mm = current->mm; struct vm_area_struct *vma; - down_write(&mm->mmap_sem); + if (down_write_killable(&mm->mmap_sem)) { + drm_gem_object_unreference_unlocked(obj); + return -EINTR; + } vma = find_vma(mm, addr); if (vma) vma->vm_page_prot = -- 2.39.5