From: Christian Borntraeger <borntrae...@de.ibm.com>

[ 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 <borntrae...@de.ibm.com>
Signed-off-by: Vasily Gorbik <g...@linux.ibm.com>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
 arch/s390/include/asm/uaccess.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/s390/include/asm/uaccess.h b/arch/s390/include/asm/uaccess.h
index bd2fd9a7821da..a470f1fa9f2af 100644
--- a/arch/s390/include/asm/uaccess.h
+++ b/arch/s390/include/asm/uaccess.h
@@ -83,7 +83,7 @@ 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 = 0x010000UL;
        int rc;
@@ -113,7 +113,7 @@ 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 = 0x01UL;
        int rc;
-- 
2.20.1

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