diff mbox

drm/tegra: bad irqsave/restore in tegra_dc_finish_page_flip()

Message ID 20150107110126.GA14864@mwanda
State Accepted, archived
Headers show

Commit Message

Dan Carpenter Jan. 7, 2015, 11:01 a.m. UTC 
We can't save two values to the IRQ flags at the same time so the IRQs
are not enabled at the end.  This kind of bug is easy to miss in testing
if the function is normally called with IRQs disabled so we wouldn't
enable IRQs anyway.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

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Comments

Thierry Reding Jan. 7, 2015, 1:46 p.m. UTC | #1 
On Wed, Jan 07, 2015 at 02:01:26PM +0300, Dan Carpenter wrote:
> We can't save two values to the IRQ flags at the same time so the IRQs
> are not enabled at the end.  This kind of bug is easy to miss in testing
> if the function is normally called with IRQs disabled so we wouldn't
> enable IRQs anyway.
> 
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

Good catch, applied.

Thanks,
Thierry
diff mbox

Patch

diff --git a/drivers/gpu/drm/tegra/dc.c b/drivers/gpu/drm/tegra/dc.c
index ae26cc0..c746161 100644
--- a/drivers/gpu/drm/tegra/dc.c
+++ b/drivers/gpu/drm/tegra/dc.c
@@ -838,7 +838,7 @@  static void tegra_dc_finish_page_flip(struct tegra_dc *dc)
 
 	bo = tegra_fb_get_plane(crtc->primary->fb, 0);
 
-	spin_lock_irqsave(&dc->lock, flags);
+	spin_lock(&dc->lock);
 
 	/* check if new start address has been latched */
 	tegra_dc_writel(dc, WINDOW_A_SELECT, DC_CMD_DISPLAY_WINDOW_HEADER);
@@ -846,7 +846,7 @@  static void tegra_dc_finish_page_flip(struct tegra_dc *dc)
 	base = tegra_dc_readl(dc, DC_WINBUF_START_ADDR);
 	tegra_dc_writel(dc, 0, DC_CMD_STATE_ACCESS);
 
-	spin_unlock_irqrestore(&dc->lock, flags);
+	spin_unlock(&dc->lock);
 
 	if (base == bo->paddr + crtc->primary->fb->offsets[0]) {
 		drm_crtc_send_vblank_event(crtc, dc->event);