From: Dmitry Vyukov dvyukov@google.com
[ Upstream commit b4142fc4d52d051d4d8df1fb6c569e5b445d369e ]
vkms_vblank_simulate() uses WARN_ON for timing-dependent condition (timer overrun). This is a mis-use of WARN_ON, WARN_ON must be used to denote kernel bugs. Use pr_warn() instead.
Signed-off-by: Dmitry Vyukov dvyukov@google.com Reported-by: syzbot+4fc21a003c8332eb0bdd@syzkaller.appspotmail.com Cc: Rodrigo Siqueira rodrigosiqueiramelo@gmail.com Cc: Melissa Wen melissa.srw@gmail.com Cc: Haneen Mohammed hamohammed.sa@gmail.com Cc: Daniel Vetter daniel@ffwll.ch Cc: David Airlie airlied@linux.ie Cc: dri-devel@lists.freedesktop.org Cc: linux-kernel@vger.kernel.org Acked-by: Melissa Wen melissa.srw@gmail.com Signed-off-by: Melissa Wen melissa.srw@gmail.com Link: https://patchwork.freedesktop.org/patch/msgid/20210320132840.1315853-1-dvyuk... Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/vkms/vkms_crtc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/vkms/vkms_crtc.c b/drivers/gpu/drm/vkms/vkms_crtc.c index 0443b7deeaef..758d8a98d96b 100644 --- a/drivers/gpu/drm/vkms/vkms_crtc.c +++ b/drivers/gpu/drm/vkms/vkms_crtc.c @@ -18,7 +18,8 @@ static enum hrtimer_restart vkms_vblank_simulate(struct hrtimer *timer)
ret_overrun = hrtimer_forward_now(&output->vblank_hrtimer, output->period_ns); - WARN_ON(ret_overrun != 1); + if (ret_overrun != 1) + pr_warn("%s: vblank timer overrun\n", __func__);
spin_lock(&output->lock); ret = drm_crtc_handle_vblank(crtc);