Hi,
--verbose please. Do you see the same hang? Does the patch fix it?
--- a/drivers/gpu/drm/ttm/ttm_execbuf_util.c +++ b/drivers/gpu/drm/ttm/ttm_execbuf_util.c @@ -97,8 +97,9 @@ int ttm_eu_reserve_buffers(struct ww_acq struct list_head *dups, bool del_lru)
[ ... ]
if (locked)ttm_eu_backoff_reservation_reverse(list, entry);
Hmm, I think the patch is wrong. As far I know it is the qxl drivers's job to call ttm_eu_backoff_reservation(). Doing that automatically in ttm will most likely break other ttm users.
So I guess the call is missing in the qxl driver somewhere, most likely in some error handling code path given that this bug is a relatively rare event.
There is only a single ttm_eu_reserve_buffers() call in qxl. So how about this?
----------------------- cut here -------------------- diff --git a/drivers/gpu/drm/qxl/qxl_release.c b/drivers/gpu/drm/qxl/qxl_release.c index 312216caeea2..2f9950fa0b8d 100644 --- a/drivers/gpu/drm/qxl/qxl_release.c +++ b/drivers/gpu/drm/qxl/qxl_release.c @@ -262,18 +262,20 @@ int qxl_release_reserve_list(struct qxl_release *release, bool no_intr) ret = ttm_eu_reserve_buffers(&release->ticket, &release->bos, !no_intr, NULL, true); if (ret) - return ret; + goto err_backoff;
list_for_each_entry(entry, &release->bos, tv.head) { struct qxl_bo *bo = to_qxl_bo(entry->tv.bo);
ret = qxl_release_validate_bo(bo); - if (ret) { - ttm_eu_backoff_reservation(&release->ticket, &release->bos); - return ret; - } + if (ret) + goto err_backoff; } return 0; + +err_backoff: + ttm_eu_backoff_reservation(&release->ticket, &release->bos); + return ret; }
void qxl_release_backoff_reserve_list(struct qxl_release *release) ----------------------- cut here --------------------
cheers, Gerd