RE: [PATCH] x86: Optimise x86 IP checksum code

[David Laight <David.Laight@ACULAB.COM>]

From: kbuild test robot
> Sent: 06 December 2019 01:45
> 
> [auto build test WARNING on tip/auto-latest]
> [also build test WARNING on tip/x86/core linus/master v5.4 next-20191202]
> [if your patch is applied to the wrong git tree, please drop us a note to help
> improve the system. BTW, we also suggest to use '--base' option to specify the
> base tree in git format-patch, please see https://stackoverflow.com/a/37406982]
> 
> url:    https://github.com/0day-ci/linux/commits/David-Laight/x86-Optimise-x86-IP-checksum-code/20191203-211313
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git e445033e58108a9891abfbc0dea90b066a75e4a9
> reproduce:
>         # apt-get install sparse
>         # sparse version: v0.6.1-91-g817270f-dirty
>         make ARCH=x86_64 allmodconfig
>         make C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__'
> 
> If you fix the issue, kindly add following tag
> Reported-by: kbuild test robot <lkp@intel.com>
> 
> 
> sparse warnings: (new ones prefixed by >>)
> 
> >> arch/x86/lib/csum-partial_64.c:141:23: sparse: sparse: incorrect type in return expression (different base types) @@    expected
> restricted __wsum @@    got icted __wsum @@
> >> arch/x86/lib/csum-partial_64.c:141:23: sparse:    expected restricted __wsum
> >> arch/x86/lib/csum-partial_64.c:141:23: sparse:    got unsigned int
> 
> vim +141 arch/x86/lib/csum-partial_64.c
> 
...
>    138	 */
>    139	__wsum csum_partial(const void *buff, int len, __wsum sum)
>    140	{
>  > 141		return do_csum(buff, len, (__force u32)sum);
>    142	}
>    143	EXPORT_SYMBOL(csum_partial);
>    144

I can regenerate the patch with the (__force __wsum) cast added back in.

Anyone going to review the changes?
I've tested all (I hope) of the corner cases in a user-space test program.

	David

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