From: Gustavo A. R. Silva gustavoars@kernel.org
commit 336feb502a715909a8136eb6a62a83d7268a353b upstream.
Fix the following -Wstringop-overflow warnings when building with GCC-11:
drivers/gpu/drm/i915/intel_pm.c:3106:9: warning: ‘intel_read_wm_latency’ accessing 16 bytes in a region of size 10 [-Wstringop-overflow=] 3106 | intel_read_wm_latency(dev_priv, dev_priv->wm.pri_latency); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/i915/intel_pm.c:3106:9: note: referencing argument 2 of type ‘u16 *’ {aka ‘short unsigned int *’} drivers/gpu/drm/i915/intel_pm.c:2861:13: note: in a call to function ‘intel_read_wm_latency’ 2861 | static void intel_read_wm_latency(struct drm_i915_private *dev_priv, | ^~~~~~~~~~~~~~~~~~~~~
by removing the over-specified array size from the argument declarations.
It seems that this code is actually safe because the size of the array depends on the hardware generation, and the function checks for that.
Notice that wm can be an array of 5 elements: drivers/gpu/drm/i915/intel_pm.c:3109: intel_read_wm_latency(dev_priv, dev_priv->wm.pri_latency);
or an array of 8 elements: drivers/gpu/drm/i915/intel_pm.c:3131: intel_read_wm_latency(dev_priv, dev_priv->wm.skl_latency);
and the compiler legitimately complains about that.
This helps with the ongoing efforts to globally enable -Wstringop-overflow.
Link: https://github.com/KSPP/linux/issues/181 Signed-off-by: Gustavo A. R. Silva gustavoars@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/i915/intel_pm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -2083,7 +2083,7 @@ hsw_compute_linetime_wm(const struct int PIPE_WM_LINETIME_TIME(linetime); }
-static void intel_read_wm_latency(struct drm_device *dev, uint16_t wm[8]) +static void intel_read_wm_latency(struct drm_device *dev, uint16_t wm[]) { struct drm_i915_private *dev_priv = to_i915(dev);