[PATCH 2/2] drm/amd/amdgpu: skip amdgpu_gem_va_update_vm when shadow page directory is swapped out

[nhaehnle@xxxxxxxxx (Nicolai Hähnle)]

From: Nicolai Hähnle <nicolai.haehnle@xxxxxxx>

This fixes a crash with the following stack trace:

 amdgpu_gtt_mgr_alloc
 amdgpu_ttm_bind
 amdgpu_vm_update_page_directory
 amdgpu_gem_va_update_vm

Signed-off-by: Nicolai Hähnle <nicolai.haehnle at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
index fbfbe5a..ffb3e70 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
@@ -495,20 +495,21 @@ static int amdgpu_gem_va_check(void *param, struct amdgpu_bo *bo)
  *
  * Update the bo_va directly after setting it's address. Errors are not
  * vital here, so they are not reported back to userspace.
  */
 static void amdgpu_gem_va_update_vm(struct amdgpu_device *adev,
 				    struct amdgpu_bo_va *bo_va,
 				    uint32_t operation)
 {
 	struct ttm_validate_buffer tv, *entry;
 	struct amdgpu_bo_list_entry vm_pd;
+	struct amdgpu_bo *pd_shadow;
 	struct ww_acquire_ctx ticket;
 	struct list_head list, duplicates;
 	unsigned domain;
 	int r;
 
 	INIT_LIST_HEAD(&list);
 	INIT_LIST_HEAD(&duplicates);
 
 	tv.bo = &bo_va->bo->tbo;
 	tv.shared = true;
@@ -521,20 +522,30 @@ static void amdgpu_gem_va_update_vm(struct amdgpu_device *adev,
 	if (r)
 		goto error_print;
 
 	list_for_each_entry(entry, &list, head) {
 		domain = amdgpu_mem_type_to_domain(entry->bo->mem.mem_type);
 		/* if anything is swapped out don't swap it in here,
 		   just abort and wait for the next CS */
 		if (domain == AMDGPU_GEM_DOMAIN_CPU)
 			goto error_unreserve;
 	}
+
+	/* Also abort if the page directory shadow has been swapped out. */
+	pd_shadow = bo_va->vm->page_directory->shadow;
+	if (pd_shadow) {
+		domain = amdgpu_mem_type_to_domain(pd_shadow->tbo.mem.mem_type);
+
+		if (domain == AMDGPU_GEM_DOMAIN_CPU)
+			goto error_unreserve;
+	}
+
 	r = amdgpu_vm_validate_pt_bos(adev, bo_va->vm, amdgpu_gem_va_check,
 				      NULL);
 	if (r)
 		goto error_unreserve;
 
 	r = amdgpu_vm_update_page_directory(adev, bo_va->vm);
 	if (r)
 		goto error_unreserve;
 
 	r = amdgpu_vm_clear_freed(adev, bo_va->vm);
-- 
2.7.4