[AMD Official Use Only]
It is the internal staging drm-next.
-----Original Message----- From: Koenig, Christian Christian.Koenig@amd.com Sent: 2021年9月6日 19:26 To: Pan, Xinhui Xinhui.Pan@amd.com; amd-gfx@lists.freedesktop.org Cc: Deucher, Alexander Alexander.Deucher@amd.com; chenli@uniontech.com; dri-devel@lists.freedesktop.org Subject: Re: [PATCH v2 1/2] drm/ttm: Fix a deadlock if the target BO is not idle during swap
Which branch is this patch based on? Please rebase on top drm-misc-fixes and resend.
Thanks, Christian.
Am 06.09.21 um 03:12 schrieb xinhui pan:
The ret value might be -EBUSY, caller will think lru lock is still locked but actually NOT. So return -ENOSPC instead. Otherwise we hit list corruption.
ttm_bo_cleanup_refs might fail too if BO is not idle. If we return 0, caller(ttm_tt_populate -> ttm_global_swapout ->ttm_device_swapout) will be stuck as we actually did not free any BO memory. This usually happens when the fence is not signaled for a long time.
Signed-off-by: xinhui pan xinhui.pan@amd.com Reviewed-by: Christian König christian.koenig@amd.com
drivers/gpu/drm/ttm/ttm_bo.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c index 1fedd0eb67ba..f1367107925b 100644 --- a/drivers/gpu/drm/ttm/ttm_bo.c +++ b/drivers/gpu/drm/ttm/ttm_bo.c @@ -1159,9 +1159,9 @@ int ttm_bo_swapout(struct ttm_buffer_object *bo, struct ttm_operation_ctx *ctx, }
if (bo->deleted) {
ttm_bo_cleanup_refs(bo, false, false, locked);
ret = ttm_bo_cleanup_refs(bo, false, false, locked); ttm_bo_put(bo);
return 0;
return ret == -EBUSY ? -ENOSPC : ret; } ttm_bo_move_to_pinned(bo);@@ -1215,7 +1215,7 @@ int ttm_bo_swapout(struct ttm_buffer_object *bo, struct ttm_operation_ctx *ctx, if (locked) dma_resv_unlock(bo->base.resv); ttm_bo_put(bo);
return ret;
return ret == -EBUSY ? -ENOSPC : ret;}
void ttm_bo_tt_destroy(struct ttm_buffer_object *bo)