lkml.org 
[lkml]   [2021]   [Apr]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] parisc: avoid a warning on u8 cast for cmpxchg on u8 pointers
From
Date
On 4/6/21 6:59 AM, Gao Xiang wrote:
> From: Gao Xiang <hsiangkao@redhat.com>
>
> 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@intel.com
> [2] https://lore.kernel.org/r/202012291914.T5Agcn99-lkp@intel.com
> [3] https://lore.kernel.org/r/202008210829.KVwn7Xeh%25lkp@intel.com
> [4] https://lore.kernel.org/r/20210315131512.133720-2-jacopo+renesas@jmondi.org
> Cc: Liam Beguin <liambeguin@gmail.com>
> Cc: Helge Deller <deller@gmx.de>
> Signed-off-by: Gao Xiang <hsiangkao@redhat.com>

applied to the parisc for-next git tree.
(I fixed up the typo above too)

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;
>

\
 
 \ /
  Last update: 2021-04-06 12:11    [W:0.047 / U:0.264 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site