s390/cmpxchg: use unsigned long values instead of void pointers

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gcc and clang warn about incompatible pointer types due to the recent
cmpxchg changes:

drivers/gpu/drm/drm_lock.c:75:10: error: passing 'typeof (lock)' (aka 'volatile unsigned int *') to parameter of type 'void *' discards qualifiers [-Werror,-Wincompatible-pointer-types-discards-qualifiers]
                   prev = cmpxchg(lock, old, new);
                          ^~~~~~~~~~~~~~~~~~~~~~~
   include/asm-generic/atomic-instrumented.h:1685:2: note: expanded from macro 'cmpxchg'
           arch_cmpxchg(__ai_ptr, __VA_ARGS__); \
           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

To avoid this simply cast pointers to unsigned long and use them
instead of void pointers. This allows to stay with functions, instead
of using complex defines and having to deal with all their potential
side effects.

Reported-by: kernel test robot <lkp@intel.com>
Fixes: d2b1f6d2d3 ("s390/cmpxchg: get rid of gcc atomic builtins")
Link: https://lore.kernel.org/linux-s390/202104130131.sMmSqpb5-lkp@intel.com/
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

...

This commit is contained in:

Heiko Carstens 2021-04-13 11:23:30 +02:00

parent 9d42a4d3e2

commit 13525f0a62

1 changed files with 23 additions and 26 deletions

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arch/s390/include/asm/cmpxchg.h

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