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s390/uaccess: avoid (false positive) compiler warnings

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[ Upstream commit 062795fcdcb2d22822fb42644b1d76a8ad8439b3 ]

Depending on inlining decisions by the compiler, __get/put_user_fn
might become out of line. Then the compiler is no longer able to tell
that size can only be 1,2,4 or 8 due to the check in __get/put_user
resulting in false positives like

./arch/s390/include/asm/uaccess.h: In function ‘__put_user_fn’:
./arch/s390/include/asm/uaccess.h:113:9: warning: ‘rc’ may be used uninitialized in this function [-Wmaybe-uninitialized]
  113 |  return rc;
      |         ^~
./arch/s390/include/asm/uaccess.h: In function ‘__get_user_fn’:
./arch/s390/include/asm/uaccess.h:143:9: warning: ‘rc’ may be used uninitialized in this function [-Wmaybe-uninitialized]
  143 |  return rc;
      |         ^~

These functions are supposed to be always inlined. Mark it as such.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Christian Borntraeger 2019-10-08 17:02:32 +02:00 committed by Greg Kroah-Hartman
parent 640fb32d61
commit fbfd8dadf5
1 changed files with 2 additions and 2 deletions
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4
arch/s390/include/asm/uaccess.h
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@ -95,7 +95,7 @@ raw_copy_to_user(void __user *to, const void *from, unsigned long n);
__rc; \
})
static inline int __put_user_fn(void *x, void __user *ptr, unsigned long size)
static __always_inline int __put_user_fn(void *x, void __user *ptr, unsigned long size)
{
unsigned long spec = 0x810000UL;
int rc;
@ -125,7 +125,7 @@ static inline int __put_user_fn(void *x, void __user *ptr, unsigned long size)
return rc;
}
static inline int __get_user_fn(void *x, const void __user *ptr, unsigned long size)
static __always_inline int __get_user_fn(void *x, const void __user *ptr, unsigned long size)
{
unsigned long spec = 0x81UL;
int rc;