We attempt to get fences earlier in the hopes that everything will already have fences and no callbacks will be needed. If we do succeed in getting a fence, getting one a second time will result in a duplicate ref with no unref. This is causing memory leaks in Vulkan applications that create a lot of fences; playing for a few hours can, apparently, bring down the system. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=107899 Signed-off-by: Jason Ekstrand <jason@xxxxxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx --- drivers/gpu/drm/drm_syncobj.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/gpu/drm/drm_syncobj.c b/drivers/gpu/drm/drm_syncobj.c index adb3cb27d31e..759278fef35a 100644 --- a/drivers/gpu/drm/drm_syncobj.c +++ b/drivers/gpu/drm/drm_syncobj.c @@ -97,6 +97,8 @@ static int drm_syncobj_fence_get_or_add_callback(struct drm_syncobj *syncobj, { int ret; + WARN_ON(*fence); + *fence = drm_syncobj_fence_get(syncobj); if (*fence) return 1; @@ -743,6 +745,9 @@ static signed long drm_syncobj_array_wait_timeout(struct drm_syncobj **syncobjs, if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT) { for (i = 0; i < count; ++i) { + if (entries[i].fence) + continue; + drm_syncobj_fence_get_or_add_callback(syncobjs[i], &entries[i].fence, &entries[i].syncobj_cb, -- 2.17.1