diff options
| author | Nathan Chancellor <nathan@kernel.org> | 2023-05-26 08:47:40 -0700 |
|---|---|---|
| committer | Dave Hansen <dave.hansen@linux.intel.com> | 2023-05-29 06:52:32 -0700 |
| commit | 2fe1e67e6987b6f05329740da79c8150a2205b0d (patch) | |
| tree | 5dba4fe5eefe76b240c385bfe7a36c1242cc184a /arch/x86/lib | |
| parent | 688eb8191b475db5acfd48634600b04fd3dda9ad (diff) | |
x86/csum: Fix clang -Wuninitialized in csum_partial()
Clang warns:
arch/x86/lib/csum-partial_64.c:74:20: error: variable 'result' is uninitialized when used here [-Werror,-Wuninitialized]
return csum_tail(result, temp64, odd);
^~~~~~
arch/x86/lib/csum-partial_64.c:48:22: note: initialize the variable 'result' to silence this warning
unsigned odd, result;
^
= 0
1 error generated.
The only initialization and uses of result in csum_partial() were moved
into csum_tail() but result is still being passed by value to
csum_tail() (clang's -Wuninitialized does not do interprocedural
analysis to realize that result is always assigned in csum_tail()
however). Sink the declaration of result into csum_tail() to clear up
the warning.
Closes: https://lore.kernel.org/202305262039.3HUYjWJk-lkp@intel.com/
Fixes: 688eb8191b47 ("x86/csum: Improve performance of `csum_partial`")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/all/20230526-csum_partial-wuninitialized-v1-1-ebc0108dcec1%40kernel.org
Diffstat (limited to 'arch/x86/lib')
| -rw-r--r-- | arch/x86/lib/csum-partial_64.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/arch/x86/lib/csum-partial_64.c b/arch/x86/lib/csum-partial_64.c index fe5861951b15..cea25ca8b8cf 100644 --- a/arch/x86/lib/csum-partial_64.c +++ b/arch/x86/lib/csum-partial_64.c @@ -21,8 +21,10 @@ static inline unsigned short from32to16(unsigned a) return b; } -static inline __wsum csum_tail(unsigned int result, u64 temp64, int odd) +static inline __wsum csum_tail(u64 temp64, int odd) { + unsigned int result; + result = add32_with_carry(temp64 >> 32, temp64 & 0xffffffff); if (unlikely(odd)) { result = from32to16(result); @@ -45,7 +47,7 @@ static inline __wsum csum_tail(unsigned int result, u64 temp64, int odd) __wsum csum_partial(const void *buff, int len, __wsum sum) { u64 temp64 = (__force u64)sum; - unsigned odd, result; + unsigned odd; odd = 1 & (unsigned long) buff; if (unlikely(odd)) { @@ -71,7 +73,7 @@ __wsum csum_partial(const void *buff, int len, __wsum sum) "adcq $0,%[res]" : [res] "+r"(temp64) : [src] "r"(buff), "m"(*(const char(*)[40])buff)); - return csum_tail(result, temp64, odd); + return csum_tail(temp64, odd); } if (unlikely(len >= 64)) { /* @@ -141,7 +143,7 @@ __wsum csum_partial(const void *buff, int len, __wsum sum) : [res] "+r"(temp64) : [trail] "r"(trail)); } - return csum_tail(result, temp64, odd); + return csum_tail(temp64, odd); } EXPORT_SYMBOL(csum_partial); |