Re: [Intel-gfx] include/drm/i915_drm.h:96: possible bad bitmask ?

From: Dave Airlie
Date: Mon Aug 08 2016 - 22:59:52 EST


On 8 August 2016 at 19:40, Daniel Vetter <daniel@xxxxxxxx> wrote:
> On Mon, Aug 08, 2016 at 10:31:32AM +0100, David Binderman wrote:
>> Hello there,
>>
>> Recent versions of gcc say this:
>>
>> include/drm/i915_drm.h:96:34: warning: result of â65535 << 20â
>> requires 37 bits to represent, but âintâ only has 32 bits
>> [-Wshift-overflow=]
>>
>> Source code is
>>
>> #define INTEL_BSM_MASK (0xFFFF << 20)
>>
>> Maybe something like
>>
>> #define INTEL_BSM_MASK (0xFFFFUL<< 20)
>>
>> might be better.
>
> Yup. Care to bake this into a patch (with s-o-b and everything per
> Documentation/SubmittingPatches) so I can apply it?

Why would you want to apply a clearly incorrect patch :-)

INTEL_BSM_MASK is used in one place, on a 32-bit number

I'm not sure what it needs to be, but a 64-bit number it doesn't.

Dave.