Michael Ellerman 01e6a61ace powerpc/64: Fix atomic64_inc_not_zero() to return an int ... Although it's not documented anywhere, there is an expectation that atomic64_inc_not_zero() returns a result which fits in an int. This is the behaviour implemented on all arches except powerpc. This has caused at least one bug in practice, in the percpu-refcount code, where the long result from our atomic64_inc_not_zero() was truncated to an int leading to lost references and stuck systems. That was worked around in that code in commit 966d2b04e0 ("percpu-refcount: fix reference leak during percpu-atomic transition"). To the best of my grepping abilities there are no other callers in-tree which truncate the value, but we should fix it anyway. Because the breakage is subtle and potentially very harmful I'm also tagging it for stable. Code generation is largely unaffected because in most cases the callers are just using the result for a test anyway. In particular the case of fget() that was mentioned in commit a6cf7ed511 ("powerpc/atomic: Implement atomic*_inc_not_zero") generates exactly the same code. Fixes: a6cf7ed511 ("powerpc/atomic: Implement atomic*_inc_not_zero") Cc: stable@vger.kernel.org # v3.4 Noticed-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>		2017-07-12 21:49:55 +10:00
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asm	powerpc/64: Fix atomic64_inc_not_zero() to return an int	2017-07-12 21:49:55 +10:00
uapi/asm	powerpc updates for 4.13	2017-07-07 13:55:45 -07:00