On Tue, Apr 06, 2021 at 12:08:55PM +0200, Helge Deller wrote:
> On 4/6/21 6:59 AM, Gao Xiang wrote:
> > From: Gao Xiang <hsiangkao@xxxxxxxxxx>
> >
> > commit b344d6a83d01 ("parisc: add support for cmpxchg on u8 pointers")
> > can generate a sparse warningi ("cast truncates bits from constant
> > value"), which has been reported several times [1] [2] [3].
> >
> > The original code worked as expected, but anyway, let silence such
> > sparse warning as what others did [4].
> >
> > [1] https://lore.kernel.org/r/202104061220.nRMBwCXw-lkp@xxxxxxxxx
> > [2] https://lore.kernel.org/r/202012291914.T5Agcn99-lkp@xxxxxxxxx
> > [3] https://lore.kernel.org/r/202008210829.KVwn7Xeh%25lkp@xxxxxxxxx
> > [4] https://lore.kernel.org/r/20210315131512.133720-2-jacopo+renesas@xxxxxxxxxx
> > Cc: Liam Beguin <liambeguin@xxxxxxxxx>
> > Cc: Helge Deller <deller@xxxxxx>
> > Signed-off-by: Gao Xiang <hsiangkao@xxxxxxxxxx>
>
> applied to the parisc for-next git tree.
> (I fixed up the typo above too)
Thanks all! :)
Thanks,
Gao Xiang
>
> Thanks!
> Helge
>
> > ---
> > arch/parisc/include/asm/cmpxchg.h | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/arch/parisc/include/asm/cmpxchg.h b/arch/parisc/include/asm/cmpxchg.h
> > index cf5ee9b0b393..84ee232278a6 100644
> > --- a/arch/parisc/include/asm/cmpxchg.h
> > +++ b/arch/parisc/include/asm/cmpxchg.h
> > @@ -72,7 +72,7 @@ __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new_, int size)
> > #endif
> > case 4: return __cmpxchg_u32((unsigned int *)ptr,
> > (unsigned int)old, (unsigned int)new_);
> > - case 1: return __cmpxchg_u8((u8 *)ptr, (u8)old, (u8)new_);
> > + case 1: return __cmpxchg_u8((u8 *)ptr, old & 0xff, new_ & 0xff);
> > }
> > __cmpxchg_called_with_bad_pointer();
> > return old;
> >
>
