Re: [PATCH 0/4] Backported amdgpu ttm deadlock fixes for 4.14

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Am 01.12.2017 um 01:23 schrieb Lyude Paul:
I haven't gone to see where it started, but as of late a good number of
pretty nasty deadlock issues have appeared with the kernel. Easy
reproduction recipe on a laptop with i915/amdgpu prime with lockdep enabled:

DRI_PRIME=1 glxinfo

Acked-by: Christian König <christian.koenig@xxxxxxx>

Thanks for taking care of this,
Christian.


Additionally, some more race conditions exist that I've managed to
trigger with piglit and lockdep enabled after applying these patches:

     =============================
     WARNING: suspicious RCU usage
     4.14.3Lyude-Test+ #2 Not tainted
     -----------------------------
     ./include/linux/reservation.h:216 suspicious rcu_dereference_protected() usage!

     other info that might help us debug this:

     rcu_scheduler_active = 2, debug_locks = 1
     1 lock held by ext_image_dma_b/27451:
      #0:  (reservation_ww_class_mutex){+.+.}, at: [<ffffffffa034f2ff>] ttm_bo_unref+0x9f/0x3c0 [ttm]

     stack backtrace:
     CPU: 0 PID: 27451 Comm: ext_image_dma_b Not tainted 4.14.3Lyude-Test+ #2
     Hardware name: HP HP ZBook 15 G4/8275, BIOS P70 Ver. 01.02 06/09/2017
     Call Trace:
      dump_stack+0x8e/0xce
      lockdep_rcu_suspicious+0xc5/0x100
      reservation_object_copy_fences+0x292/0x2b0
      ? ttm_bo_unref+0x9f/0x3c0 [ttm]
      ttm_bo_unref+0xbd/0x3c0 [ttm]
      amdgpu_bo_unref+0x2a/0x50 [amdgpu]
      amdgpu_gem_object_free+0x4b/0x50 [amdgpu]
      drm_gem_object_free+0x1f/0x40 [drm]
      drm_gem_object_put_unlocked+0x40/0xb0 [drm]
      drm_gem_object_handle_put_unlocked+0x6c/0xb0 [drm]
      drm_gem_object_release_handle+0x51/0x90 [drm]
      drm_gem_handle_delete+0x5e/0x90 [drm]
      ? drm_gem_handle_create+0x40/0x40 [drm]
      drm_gem_close_ioctl+0x20/0x30 [drm]
      drm_ioctl_kernel+0x5d/0xb0 [drm]
      drm_ioctl+0x2f7/0x3b0 [drm]
      ? drm_gem_handle_create+0x40/0x40 [drm]
      ? trace_hardirqs_on_caller+0xf4/0x190
      ? trace_hardirqs_on+0xd/0x10
      amdgpu_drm_ioctl+0x4f/0x90 [amdgpu]
      do_vfs_ioctl+0x93/0x670
      ? __fget+0x108/0x1f0
      SyS_ioctl+0x79/0x90
      entry_SYSCALL_64_fastpath+0x23/0xc2

I've also added the relevant fixes for the issue mentioned above.

Christian König (3):
   drm/ttm: fix ttm_bo_cleanup_refs_or_queue once more
   dma-buf: make reservation_object_copy_fences rcu save
   drm/amdgpu: reserve root PD while releasing it

Michel Dänzer (1):
   drm/ttm: Always and only destroy bo->ttm_resv in ttm_bo_release_list

  drivers/dma-buf/reservation.c          | 56 +++++++++++++++++++++++++---------
  drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 13 ++++++--
  drivers/gpu/drm/ttm/ttm_bo.c           | 43 +++++++++++++-------------
  3 files changed, 74 insertions(+), 38 deletions(-)

--
2.14.3

_______________________________________________
amd-gfx mailing list
amd-gfx@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/amd-gfx




[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]