ARM: 8475/1: SWP emulation: Restore original *data when failed

__user_swpX_asm maybe failed in first STREX operation, emulate_swpX
will try again, but the *data has been changed in first time. which
causes the result is wrong.
This patch is to fix this issue. When STREX succeed, change the *data.
if it fail, *data is not changed.

Signed-off-by: Shengjiu Wang <shengjiu.wang@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Shengjiu Wang 2015-12-08 13:37:19 +01:00 committed by Russell King
parent fa0708b320
commit 34bfbae33a

View file

@ -36,10 +36,10 @@
*/
#define __user_swpX_asm(data, addr, res, temp, B) \
__asm__ __volatile__( \
" mov %2, %1\n" \
"0: ldrex"B" %1, [%3]\n" \
"1: strex"B" %0, %2, [%3]\n" \
"0: ldrex"B" %2, [%3]\n" \
"1: strex"B" %0, %1, [%3]\n" \
" cmp %0, #0\n" \
" moveq %1, %2\n" \
" movne %0, %4\n" \
"2:\n" \
" .section .text.fixup,\"ax\"\n" \