On 2024-04-08 3:55, Christian König wrote:
Am 07.04.24 um 06:52 schrieb Lang Yu:
When VM is in evicting state, amdgpu_vm_update_range would return
-EBUSY.
Then restore_process_worker runs into a dead loop.
Fixes: 2fdba514ad5a ("drm/amdgpu: Auto-validate DMABuf imports in
compute VMs")
Mhm, while it would be good to have this case handled as error it
should never occur in practice since we should have validated the VM
before validating the DMA-bufs.
@Felix isn't that something we have taken care of?
The problem I saw when I implemented Auto-validate was, that migration
of a BO invalidates its DMABuf attachments. So I need to validate the
DMABuf attachments after validating the BOs they attach to. This
auto-validation happens in amdgpu_vm_validate. So I needed to do the VM
validation after the BO validation. The problem now seems to be that the
BO validation happens in the same loop as the page table update. And the
page table update fails if the VM is not valid.
I never saw this problem in my testing, probably because I never got my
page tables evicted?
Anyway, I think the solution is to split the BO validation and page
table update into two separate loops in amdgpu_amdkfd_restore_process_pos:
1. Validate BOs
2. Validate VM (and DMABuf attachments)
3. Update page tables for the BOs validated above
Regards,
Felix
Regards,
Christian.
Signed-off-by: Lang Yu <lang...@amd.com>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
index 0ae9fd844623..8c71fe07807a 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
@@ -2900,6 +2900,12 @@ int
amdgpu_amdkfd_gpuvm_restore_process_bos(void *info, struct dma_fence
__rcu *
amdgpu_sync_create(&sync_obj);
+ ret = process_validate_vms(process_info, NULL);
+ if (ret) {
+ pr_debug("Validating VMs failed, ret: %d\n", ret);
+ goto validate_map_fail;
+ }
+
/* Validate BOs and map them to GPUVM (update VM page tables). */
list_for_each_entry(mem, &process_info->kfd_bo_list,
validate_list) {
