drm/amdkfd: Fix an issue at userptr buffer validation process.

amdgpu_ttm_tt_get_user_pages can fail(-EFAULT). If it failed mem has no associated
hmm range or user_pages associated. Keep it at process_info->userptr_inval_list and
mark mem->invalid until following scheduled attempts can valid it.

Signed-off-by: Xiaogang Chen <Xiaogang.Chen@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
index 83a83ce..4432e16 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
@@ -2445,7 +2445,9 @@ static int update_invalid_user_pages(struct amdkfd_process_info *process_info,
                        ret = -EAGAIN;
                        goto unlock_out;
                }
-               mem->invalid = 0;
+                /* set mem valid if mem has hmm range associated */
+               if (mem->range)
+                       mem->invalid = 0;
        }
 
 unlock_out:
@@ -2577,8 +2579,15 @@ static int confirm_valid_user_pages_locked(struct amdkfd_process_info *process_i
        list_for_each_entry_safe(mem, tmp_mem,
                                 &process_info->userptr_inval_list,
                                 validate_list.head) {
-               bool valid = amdgpu_ttm_tt_get_user_pages_done(
-                               mem->bo->tbo.ttm, mem->range);
+               bool valid;
+
+               /* keep mem without hmm range at userptr_inval_list */
+               if (!mem->range)
+                        continue;
+
+               /* Only check mem with hmm range associated */
+               valid = amdgpu_ttm_tt_get_user_pages_done(
+                                       mem->bo->tbo.ttm, mem->range);
 
                mem->range = NULL;
                if (!valid) {
@@ -2586,7 +2595,12 @@ static int confirm_valid_user_pages_locked(struct amdkfd_process_info *process_i
                        ret = -EAGAIN;
                        continue;
                }
-               WARN(mem->invalid, "Valid BO is marked invalid");
+
+               if (mem->invalid) {
+                       WARN(1, "Valid BO is marked invalid");
+                       ret = -EAGAIN;
+                       continue;
+               }
 
                list_move_tail(&mem->validate_list.head,
                               &process_info->userptr_valid_list);