From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f66.google.com ([74.125.82.66]:32877 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754682AbcB2N1h (ORCPT ); Mon, 29 Feb 2016 08:27:37 -0500 From: Michal Hocko Subject: [PATCH 16/18] drm/i915: make i915_gem_mmap_ioctl wait for mmap_sem killable Date: Mon, 29 Feb 2016 14:26:55 +0100 Message-ID: <1456752417-9626-17-git-send-email-mhocko@kernel.org> In-Reply-To: <1456752417-9626-1-git-send-email-mhocko@kernel.org> References: <1456752417-9626-1-git-send-email-mhocko@kernel.org> Sender: linux-arch-owner@vger.kernel.org List-ID: To: LKML Cc: Andrew Morton , linux-mm@kvack.org, Alex Deucher , Alex Thorlton , Andrea Arcangeli , Andy Lutomirski , Benjamin LaHaise , =?UTF-8?q?Christian=20K=C3=B6nig?= , Daniel Vetter , Dave Hansen , David Airlie , Davidlohr Bueso , David Rientjes , "H . Peter Anvin" , Hugh Dickins , Ingo Molnar , Johannes Weiner , "Kirill A . Shutemov" , Konstantin Khlebnikov , linux-arch@vger.kernel.org, Mel Gorman , Oleg Nesterov , Peter Zijlstra , Petr Cermak , Thomas Gleixner , Michal Hocko Message-ID: <20160229132655.24-LC2G4rfn9JaRHqYsjbSQaK_ajtdMoBNTLd7Lhv4c@z> From: Michal Hocko 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. Cc: Daniel Vetter Cc: David Airlie Signed-off-by: Michal Hocko --- 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 f68f34606f2f..a50136cbd332 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 = -- 2.7.0