[ 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.v... 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 f689c75474e5..2901b7944068 100644 --- a/drivers/gpu/drm/drm_debugfs_crc.c +++ b/drivers/gpu/drm/drm_debugfs_crc.c @@ -366,7 +366,7 @@ 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; }
@@ -377,7 +377,7 @@ 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");