Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull core fix from Ingo Molnar:
 "Fix GENMASK macro shift overflow"

Nobody seems to currently use GENMASK() to fill every single last bit
(which is what overflows) in-tree, and gcc would warn about it, so we
have that going for us.  But apparently there are pending changes that
want this.

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  bitops: Fix shift overflow in GENMASK macros
This commit is contained in:
Linus Torvalds 2014-11-21 15:38:21 -08:00
commit a64bb02f4a

View file

@ -18,8 +18,11 @@
* position @h. For example
* GENMASK_ULL(39, 21) gives us the 64bit vector 0x000000ffffe00000.
*/
#define GENMASK(h, l) (((U32_C(1) << ((h) - (l) + 1)) - 1) << (l))
#define GENMASK_ULL(h, l) (((U64_C(1) << ((h) - (l) + 1)) - 1) << (l))
#define GENMASK(h, l) \
(((~0UL) << (l)) & (~0UL >> (BITS_PER_LONG - 1 - (h))))
#define GENMASK_ULL(h, l) \
(((~0ULL) << (l)) & (~0ULL >> (BITS_PER_LONG_LONG - 1 - (h))))
extern unsigned int __sw_hweight8(unsigned int w);
extern unsigned int __sw_hweight16(unsigned int w);