[PATCH] drm/amdgpu: fix the nullptr issue when reenter GPU recovery

[Li, Dennis]

[AMD Public Use]

Hi, Hawking,
      When RAS uncorrectable error happens, RAS interrupt will trigger a GPU recovery.  At the same time, if a GFX or compute job is timeout, driver will trigger a new one. 

Best Regards
Dennis Li
-----Original Message-----
From: Zhang, Hawking <Hawking.Zhang at amd.com> 
Sent: Thursday, August 20, 2020 4:24 PM
To: Li, Dennis <Dennis.Li at amd.com>; amd-gfx at lists.freedesktop.org; Deucher, Alexander <Alexander.Deucher at amd.com>; Kuehling, Felix <Felix.Kuehling at amd.com>; Koenig, Christian <Christian.Koenig at amd.com>
Cc: Li, Dennis <Dennis.Li at amd.com>
Subject: RE: [PATCH] drm/amdgpu: fix the nullptr issue when reenter GPU recovery

[AMD Public Use]

Hi Dennis,

Can you elaborate the case that driver re-enter GPU recovery in sGPU system? I'm wondering whether this is a valid case or we shall prevent this from the beginning.

Regards,
Hawking

-----Original Message-----
From: Dennis Li <Dennis.Li at amd.com> 
Sent: Thursday, August 20, 2020 10:21
To: amd-gfx at lists.freedesktop.org; Deucher, Alexander <Alexander.Deucher at amd.com>; Kuehling, Felix <Felix.Kuehling at amd.com>; Zhang, Hawking <Hawking.Zhang at amd.com>; Koenig, Christian <Christian.Koenig at amd.com>
Cc: Li, Dennis <Dennis.Li at amd.com>
Subject: [PATCH] drm/amdgpu: fix the nullptr issue when reenter GPU recovery

in single gpu system, if driver reenter gpu recovery, amdgpu_device_lock_adev will return false, but hive is nullptr now.

Signed-off-by: Dennis Li <Dennis.Li at amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index 82242e2f5658..81b1d9a1dca0 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -4371,8 +4371,8 @@ int amdgpu_device_gpu_recover(struct amdgpu_device *adev,
 		if (!amdgpu_device_lock_adev(tmp_adev)) {
 			DRM_INFO("Bailing on TDR for s_job:%llx, as another already in progress",
 				  job ? job->base.id : -1);
-			mutex_unlock(&hive->hive_lock);
-			return 0;
+			r = 0;
+			goto skip_recovery;
 		}
 
 		/*
@@ -4505,6 +4505,7 @@ int amdgpu_device_gpu_recover(struct amdgpu_device *adev,
 		amdgpu_device_unlock_adev(tmp_adev);
 	}
 
+skip_recovery:
 	if (hive) {
 		atomic_set(&hive->in_reset, 0);
 		mutex_unlock(&hive->hive_lock);
--
2.17.1