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| author | Matthew Wilcox <willy@infradead.org> | 2019-01-03 15:26:41 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-01-04 13:13:46 -0800 |
| commit | 3fc2579e6f162fcff964f5aa01c8a29438ca5c05 (patch) | |
| tree | a90c733a19c07e111d9195181d1f3a37e92ef0eb /arch/x86/include/asm/bitops.h | |
| parent | e6310f0fb5cd3f65244dbdef2fb264859891c7ec (diff) | |
| download | linux-0-day-3fc2579e6f162fcff964f5aa01c8a29438ca5c05.tar.gz linux-0-day-3fc2579e6f162fcff964f5aa01c8a29438ca5c05.tar.xz | |
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/x86/include/asm/bitops.h')
| -rw-r--r-- | arch/x86/include/asm/bitops.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/include/asm/bitops.h b/arch/x86/include/asm/bitops.h index 124f9195eb3ef..ad7b210aa3f62 100644 --- a/arch/x86/include/asm/bitops.h +++ b/arch/x86/include/asm/bitops.h @@ -448,7 +448,7 @@ static __always_inline int ffs(int x) * set bit if value is nonzero. The last (most significant) bit is * at position 32. */ -static __always_inline int fls(int x) +static __always_inline int fls(unsigned int x) { int r; |