From 9c2876d56f1ce9b6b2072f1446fb1e8d1532cb3d Mon Sep 17 00:00:00 2001 From: Lang Yu Date: Mon, 17 May 2021 12:47:20 +0800 Subject: drm/amd/amdgpu: fix a potential deadlock in gpu reset MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When amdgpu_ib_ring_tests failed, the reset logic called amdgpu_device_ip_suspend twice, then deadlock occurred. Deadlock log: [ 805.655192] amdgpu 0000:04:00.0: amdgpu: ib ring test failed (-110). [ 806.290952] [drm] free PSP TMR buffer [ 806.319406] ============================================ [ 806.320315] WARNING: possible recursive locking detected [ 806.321225] 5.11.0-custom #1 Tainted: G W OEL [ 806.322135] -------------------------------------------- [ 806.323043] cat/2593 is trying to acquire lock: [ 806.323825] ffff888136b1cdc8 (&adev->dm.dc_lock){+.+.}-{3:3}, at: dm_suspend+0xb8/0x1d0 [amdgpu] [ 806.325668] but task is already holding lock: [ 806.326664] ffff888136b1cdc8 (&adev->dm.dc_lock){+.+.}-{3:3}, at: dm_suspend+0xb8/0x1d0 [amdgpu] [ 806.328430] other info that might help us debug this: [ 806.329539] Possible unsafe locking scenario: [ 806.330549] CPU0 [ 806.330983] ---- [ 806.331416] lock(&adev->dm.dc_lock); [ 806.332086] lock(&adev->dm.dc_lock); [ 806.332738] *** DEADLOCK *** [ 806.333747] May be due to missing lock nesting notation [ 806.334899] 3 locks held by cat/2593: [ 806.335537] #0: ffff888100d3f1b8 (&attr->mutex){+.+.}-{3:3}, at: simple_attr_read+0x4e/0x110 [ 806.337009] #1: ffff888136b1fd78 (&adev->reset_sem){++++}-{3:3}, at: amdgpu_device_lock_adev+0x42/0x94 [amdgpu] [ 806.339018] #2: ffff888136b1cdc8 (&adev->dm.dc_lock){+.+.}-{3:3}, at: dm_suspend+0xb8/0x1d0 [amdgpu] [ 806.340869] stack backtrace: [ 806.341621] CPU: 6 PID: 2593 Comm: cat Tainted: G W OEL 5.11.0-custom #1 [ 806.342921] Hardware name: AMD Celadon-CZN/Celadon-CZN, BIOS WLD0C23N_Weekly_20_12_2 12/23/2020 [ 806.344413] Call Trace: [ 806.344849] dump_stack+0x93/0xbd [ 806.345435] __lock_acquire.cold+0x18a/0x2cf [ 806.346179] lock_acquire+0xca/0x390 [ 806.346807] ? dm_suspend+0xb8/0x1d0 [amdgpu] [ 806.347813] __mutex_lock+0x9b/0x930 [ 806.348454] ? dm_suspend+0xb8/0x1d0 [amdgpu] [ 806.349434] ? amdgpu_device_indirect_rreg+0x58/0x70 [amdgpu] [ 806.350581] ? _raw_spin_unlock_irqrestore+0x47/0x50 [ 806.351437] ? dm_suspend+0xb8/0x1d0 [amdgpu] [ 806.352437] ? rcu_read_lock_sched_held+0x4f/0x80 [ 806.353252] ? rcu_read_lock_sched_held+0x4f/0x80 [ 806.354064] mutex_lock_nested+0x1b/0x20 [ 806.354747] ? mutex_lock_nested+0x1b/0x20 [ 806.355457] dm_suspend+0xb8/0x1d0 [amdgpu] [ 806.356427] ? soc15_common_set_clockgating_state+0x17d/0x19 [amdgpu] [ 806.357736] amdgpu_device_ip_suspend_phase1+0x78/0xd0 [amdgpu] [ 806.360394] amdgpu_device_ip_suspend+0x21/0x70 [amdgpu] [ 806.362926] amdgpu_device_pre_asic_reset+0xb3/0x270 [amdgpu] [ 806.365560] amdgpu_device_gpu_recover.cold+0x679/0x8eb [amdgpu] Signed-off-by: Lang Yu Acked-by: Christian KÃnig Reviewed-by: Andrey Grodzovsky Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c index 8b2a37bf2adf..66ddfe4f58c2 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c @@ -4479,7 +4479,6 @@ out: r = amdgpu_ib_ring_tests(tmp_adev); if (r) { dev_err(tmp_adev->dev, "ib ring test failed (%d).\n", r); - r = amdgpu_device_ip_suspend(tmp_adev); need_full_reset = true; r = -EAGAIN; goto end; -- cgit v1.2.3