[PATCH AUTOSEL 5.1 032/141] drm/crc-debugfs: Also sprinkle irqrestore over early exits

Sasha Levin
2019-07-19T04:32:30Z

From: Daniel Vetter <daniel.vetter@ffwll.ch>

[ Upstream commit d99004d7201aa653658ff2390d6e516567c96ebc ]

I. was. blind.

Caught with vkms, which has some really slow crc computation function.

Fixes: 1882018a70e0 ("drm/crc-debugfs: User irqsafe spinlock in drm_crtc_add_crc_entry")
Cc: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Cc: Emil Velikov <emil.velikov@collabora.com>
Cc: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190606211544.5389-1-daniel.vetter@ffwll.ch
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpu/drm/drm_debugfs_crc.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/drm_debugfs_crc.c b/drivers/gpu/drm/drm_debugfs_crc.c
index 1a6a5b78e30f..fde298d9f510 100644
--- a/drivers/gpu/drm/drm_debugfs_crc.c
+++ b/drivers/gpu/drm/drm_debugfs_crc.c
@@ -395,7 +395,7 @@ int drm_crtc_add_crc_entry(struct drm_crtc *crtc, bool has_frame,

/* Caller may not have noticed yet that userspace has stopped reading */
if (!crc->entries) {
- spin_unlock(&crc->lock);
+ spin_unlock_irqrestore(&crc->lock, flags);
return -EINVAL;
}

@@ -406,7 +406,7 @@ int drm_crtc_add_crc_entry(struct drm_crtc *crtc, bool has_frame,
bool was_overflow = crc->overflow;

crc->overflow = true;
- spin_unlock(&crc->lock);
+ spin_unlock_irqrestore(&crc->lock, flags);

if (!was_overflow)
DRM_ERROR("Overflow of CRC buffer, userspace reads too slow.\n");
--
2.20.1