No, scheduler restart and device unlock must take place
inamdgpu_pci_resume (see struct pci_error_handlers for the various
states of PCI recovery). So just add a flag (probably in amdgpu_device)
so we can remember what pci_channel_state_t we came from (unfortunately
it's not passed to us in amdgpu_pci_resume) and unless it's set don't
do anything in amdgpu_pci_resume.
Andrey
On 2021-10-01 4:21 a.m., Chen, Guchun wrote:
[Public]
Hi Andrey,
Do you mean to move the code of drm_sched_resubmit_jobs and drm_sched_start in amdgpu_pci_resume to amdgpu_pci_error_detected, under the case pci_channel_io_frozen?
Then leave amdgpu_pci_resume as a null function, and in this way, we can drop the acquire/lock write lock for case of pci_channel_io_normal as well?
Regards,
Guchun
-----Original Message-----
From: Grodzovsky, Andrey <Andrey.Grodzovsky@xxxxxxx>
Sent: Friday, October 1, 2021 10:22 AM
To: Chen, Guchun <Guchun.Chen@xxxxxxx>; amd-gfx@xxxxxxxxxxxxxxxxxxxxx; Koenig, Christian <Christian.Koenig@xxxxxxx>; Pan, Xinhui <Xinhui.Pan@xxxxxxx>; Deucher, Alexander <Alexander.Deucher@xxxxxxx>
Subject: Re: [PATCH] drm/amdgpu: add missed write lock for pci detected state pci_channel_io_normal
On 2021-09-30 10:00 p.m., Guchun Chen wrote:
When a PCI error state pci_channel_io_normal is detectd, it will
report PCI_ERS_RESULT_CAN_RECOVER status to PCI driver, and PCI driver
will continue the execution of PCI resume callback report_resume by
pci_walk_bridge, and the callback will go into amdgpu_pci_resume
finally, where write lock is releasd unconditionally without acquiring
such lock.
Good catch but, the issue is even wider in scope, what about drm_sched_resubmit_jobs and drm_sched_start called without being stopped before ? Better to put the entire scope of code in this function under flag that set only in pci_channel_io_frozen. As far as i remember we don't need to do anything in case of pci_channel_io_normal.
Andrey
Fixes: c9a6b82f45e2("drm/amdgpu: Implement DPC recovery")
Signed-off-by: Guchun Chen <guchun.chen@xxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index bb5ad2b6ca13..12f822d51de2 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -5370,6 +5370,7 @@ pci_ers_result_t
amdgpu_pci_error_detected(struct pci_dev *pdev, pci_channel_sta
switch (state) {
case pci_channel_io_normal:
+ amdgpu_device_lock_adev(adev, NULL);
return PCI_ERS_RESULT_CAN_RECOVER;
/* Fatal error, prepare for slot reset */
case pci_channel_io_frozen:
