diff mbox series

drm/tegra: Fix shift overflow in tegra_shared_plane_atomic_update

Message ID 20210415152913.1363964-1-nathan@kernel.org
State Accepted
Headers show
Series drm/tegra: Fix shift overflow in tegra_shared_plane_atomic_update | expand

Commit Message

Nathan Chancellor April 15, 2021, 3:29 p.m. UTC 
Clang warns:

drivers/gpu/drm/tegra/hub.c:513:11: warning: shift count >= width of
type [-Wshift-count-overflow]
                base |= BIT(39);
                        ^~~~~~~

BIT is unsigned long, which is 32-bit on ARCH=arm, hence the overflow
warning. Switch to BIT_ULL, which is 64-bit and will not overflow.

Fixes: 7b6f846785f4 ("drm/tegra: Support sector layout on Tegra194")
Link: https://github.com/ClangBuiltLinux/linux/issues/1351
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
---
 drivers/gpu/drm/tegra/hub.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)


base-commit: 0265531f0897f890da3f9c2958707af099c7d974

Comments

Thierry Reding April 15, 2021, 3:49 p.m. UTC | #1 
On Thu, Apr 15, 2021 at 08:29:14AM -0700, Nathan Chancellor wrote:
> Clang warns:
> 
> drivers/gpu/drm/tegra/hub.c:513:11: warning: shift count >= width of
> type [-Wshift-count-overflow]
>                 base |= BIT(39);
>                         ^~~~~~~
> 
> BIT is unsigned long, which is 32-bit on ARCH=arm, hence the overflow
> warning. Switch to BIT_ULL, which is 64-bit and will not overflow.
> 
> Fixes: 7b6f846785f4 ("drm/tegra: Support sector layout on Tegra194")
> Link: https://github.com/ClangBuiltLinux/linux/issues/1351
> Signed-off-by: Nathan Chancellor <nathan@kernel.org>
> ---
>  drivers/gpu/drm/tegra/hub.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

This code never runs on 32-bit platforms, so another option would be to
not try and build this on 32-bit configurations either. But none of the
rest of the code is built conditionally, so fixing this is preferable.

Applied, thanks.

Thierry
diff mbox series

Patch

diff --git a/drivers/gpu/drm/tegra/hub.c b/drivers/gpu/drm/tegra/hub.c
index 79bff8b48271..bfae8a02f55b 100644
--- a/drivers/gpu/drm/tegra/hub.c
+++ b/drivers/gpu/drm/tegra/hub.c
@@ -510,7 +510,7 @@  static void tegra_shared_plane_atomic_update(struct drm_plane *plane,
 	 * dGPU sector layout.
 	 */
 	if (tegra_plane_state->tiling.sector_layout == TEGRA_BO_SECTOR_LAYOUT_GPU)
-		base |= BIT(39);
+		base |= BIT_ULL(39);
 #endif
 
 	tegra_plane_writel(p, tegra_plane_state->format, DC_WIN_COLOR_DEPTH);