diff options
| author | Matthew Wilcox <willy@infradead.org> | 2019-01-04 00:26:41 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-01-04 22:13:46 +0100 |
| commit | 3fc2579e6f162fcff964f5aa01c8a29438ca5c05 (patch) | |
| tree | a90c733a19c07e111d9195181d1f3a37e92ef0eb /arch/arc/include/asm/bitops.h | |
| parent | include/linux/printk.h: drop silly "static inline asmlinkage" from dump_stack() (diff) | |
| download | linux-3fc2579e6f162fcff964f5aa01c8a29438ca5c05.tar.xz linux-3fc2579e6f162fcff964f5aa01c8a29438ca5c05.zip | |
fls: change parameter to unsigned int
When testing in userspace, UBSAN pointed out that shifting into the sign
bit is undefined behaviour. It doesn't really make sense to ask for the
highest set bit of a negative value, so just turn the argument type into
an unsigned int.
Some architectures (eg ppc) already had it declared as an unsigned int,
so I don't expect too many problems.
Link: http://lkml.kernel.org/r/20181105221117.31828-1-willy@infradead.org
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/arc/include/asm/bitops.h')
| -rw-r--r-- | arch/arc/include/asm/bitops.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/arc/include/asm/bitops.h b/arch/arc/include/asm/bitops.h index 8da87feec59a..ee9246184033 100644 --- a/arch/arc/include/asm/bitops.h +++ b/arch/arc/include/asm/bitops.h @@ -278,7 +278,7 @@ static inline __attribute__ ((const)) int clz(unsigned int x) return res; } -static inline int constant_fls(int x) +static inline int constant_fls(unsigned int x) { int r = 32; @@ -312,7 +312,7 @@ static inline int constant_fls(int x) * @result: [1-32] * fls(1) = 1, fls(0x80000000) = 32, fls(0) = 0 */ -static inline __attribute__ ((const)) int fls(unsigned long x) +static inline __attribute__ ((const)) int fls(unsigned int x) { if (__builtin_constant_p(x)) return constant_fls(x); |