Re: [PATCH] drm/amdgpu: fix 32-bit compiler warning

From: Arnd Bergmann
Date: Wed Oct 07 2015 - 05:19:30 EST


On Wednesday 07 October 2015 10:57:11 Christian König wrote:
> On 07.10.2015 09:41, Arnd Bergmann wrote:
> > The new amdgpu driver passes a user space pointer in a 64-bit structure
> > member, which is the correct way to do it, but it attempts to
> > directly cast it to a __user pointer in the kernel, which causes
> > a warning in three places:
> >
> > drm/amd/amdgpu/amdgpu_cs.c: In function 'amdgpu_cs_parser_init':
> > drm/amd/amdgpu/amdgpu_cs.c:180:21: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
> > chunk_array_user = (uint64_t __user *)(cs->in.chunks);
> >
> > This changes all three to add an intermediate cast to 'unsigned long'
> > as other drivers do. This avoids the warning and works correctly on
> > both 32-bit and 64-bit architectures.
> >
> > Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
>
> Well if I'm not completely mistaken this is the second time we need to
> fix this because somebody thought the cast was unnecessary.
>
> Anyway the patch is Reviewed-by: Christian König
> <christian.koenig@xxxxxxx> and I'm going to keep an eye open for the
> next time somebody tries to remove this.
>

Ok, thanks.

I guess I should have added

Fixes: e60b344f6c0eff ("drm/amdgpu: optimize amdgpu_parser_init")

Arnd
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