Re: [PATCH] arm64: csum: cast to the proper type
On Sun, 14 Mar 2021 20:26:50 -0500, Alex Elder wrote: > The last line of ip_fast_csum() calls csum_fold(), forcing the > type of the argument passed to be u32. But csum_fold() takes a > __wsum argument (which is __u32 __bitwise for arm64). As long > as we're forcing the cast, cast it to the right type. Applied to arm64 (for-next/fixes), thanks! [1/1] arm64: csum: cast to the proper type https://git.kernel.org/arm64/c/0710442a88d1 Cheers, -- Will https://fixes.arm64.dev https://next.arm64.dev https://will.arm64.dev
Re: [PATCH] arm64: csum: cast to the proper type
On 2021-03-15 01:26, Alex Elder wrote: The last line of ip_fast_csum() calls csum_fold(), forcing the type of the argument passed to be u32. But csum_fold() takes a __wsum argument (which is __u32 __bitwise for arm64). As long as we're forcing the cast, cast it to the right type. Oddly, the commit adding the cast does specifically speak about converting to __wsum, so I'm not sure what happened there... :/ Anyway, this seems to make sense. Acked-by: Robin Murphy Signed-off-by: Alex Elder --- With this patch in place, quite a few "different base types" sparse warnings go away on a full arm64 kernel build. More specifically: warning: incorrect type in argument 1 (different base types) expected restricted __wsum [usertype] csum got unsigned int [usertype] -Alex arch/arm64/include/asm/checksum.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/checksum.h b/arch/arm64/include/asm/checksum.h index 93a161b3bf3fe..dc52b733675db 100644 --- a/arch/arm64/include/asm/checksum.h +++ b/arch/arm64/include/asm/checksum.h @@ -37,7 +37,7 @@ static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl) } while (--n > 0); sum += ((sum >> 32) | (sum << 32)); - return csum_fold((__force u32)(sum >> 32)); + return csum_fold((__force __wsum)(sum >> 32)); } #define ip_fast_csum ip_fast_csum
[PATCH] arm64: csum: cast to the proper type
The last line of ip_fast_csum() calls csum_fold(), forcing the type of the argument passed to be u32. But csum_fold() takes a __wsum argument (which is __u32 __bitwise for arm64). As long as we're forcing the cast, cast it to the right type. Signed-off-by: Alex Elder --- With this patch in place, quite a few "different base types" sparse warnings go away on a full arm64 kernel build. More specifically: warning: incorrect type in argument 1 (different base types) expected restricted __wsum [usertype] csum got unsigned int [usertype] -Alex arch/arm64/include/asm/checksum.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/checksum.h b/arch/arm64/include/asm/checksum.h index 93a161b3bf3fe..dc52b733675db 100644 --- a/arch/arm64/include/asm/checksum.h +++ b/arch/arm64/include/asm/checksum.h @@ -37,7 +37,7 @@ static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl) } while (--n > 0); sum += ((sum >> 32) | (sum << 32)); - return csum_fold((__force u32)(sum >> 32)); + return csum_fold((__force __wsum)(sum >> 32)); } #define ip_fast_csum ip_fast_csum -- 2.27.0
