5.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Erik Kurzinger <ekurzinger@xxxxxxxxxx>
[ Upstream commit 101c9f637efa1655f55876644d4439e552267527 ]
If DRM_IOCTL_SYNCOBJ_TIMELINE_WAIT is invoked with the
DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE flag set but no fence has yet been
submitted for the given timeline point the call will fail immediately
with EINVAL. This does not match the intended behavior where the call
should wait until the fence has been submitted (or the timeout expires).
The following small example program illustrates the issue. It should
wait for 5 seconds and then print ETIME, but instead it terminates right
away after printing EINVAL.
#include <stdio.h>
#include <fcntl.h>
#include <time.h>
#include <errno.h>
#include <xf86drm.h>
int main(void)
{
int fd = open("/dev/dri/card0", O_RDWR);
uint32_t syncobj;
drmSyncobjCreate(fd, 0, &syncobj);
struct timespec ts;
clock_gettime(CLOCK_MONOTONIC, &ts);
uint64_t point = 1;
if (drmSyncobjTimelineWait(fd, &syncobj, &point, 1,
ts.tv_sec * 1000000000 + ts.tv_nsec + 5000000000, // 5s
DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE, NULL)) {
printf("drmSyncobjTimelineWait failed %d\n", errno);
}
}
Fixes: 01d6c3578379 ("drm/syncobj: add support for timeline point wait v8")
Signed-off-by: Erik Kurzinger <ekurzinger@xxxxxxxxxx>
Reviewed by: Simon Ser <contact@xxxxxxxxxxx>
Signed-off-by: Simon Ser <contact@xxxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/1fac96f1-2f3f-f9f9-4eb0-340f27a8f6c0@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/drm_syncobj.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_syncobj.c b/drivers/gpu/drm/drm_syncobj.c
index 993898a2c7791..738e60139db90 100644
--- a/drivers/gpu/drm/drm_syncobj.c
+++ b/drivers/gpu/drm/drm_syncobj.c
@@ -983,7 +983,8 @@ static signed long drm_syncobj_array_wait_timeout(struct drm_syncobj **syncobjs,
fence = drm_syncobj_fence_get(syncobjs[i]);
if (!fence || dma_fence_chain_find_seqno(&fence, points[i])) {
dma_fence_put(fence);
- if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT) {
+ if (flags & (DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT |
+ DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE)) {
continue;
} else {
timeout = -EINVAL;
--
2.42.0
