[ARM] 3271/1: ARM EABI: fix calling of cmpxchg syscall emulation

Patch from Nicolas Pitre

This is kernel provided user space code.

Since a syscall is used, it has to be updated to work with EABI.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 4 insertions, 1 deletions

diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
index 874e6bb79405..d401d908c463 100644
--- a/arch/arm/kernel/entry-armv.S
+++ b/arch/arm/kernel/entry-armv.S
@@ -735,8 +735,11 @@ __kuser_cmpxchg:				@ 0xffff0fc0
          * The kernel itself must perform the operation.
          * A special ghost syscall is used for that (see traps.c).
          */
+        stmfd   sp!, {r7, lr}
+        mov     r7, #0xff00             @ 0xfff0 into r7 for EABI
+        orr     r7, r7, #0xf0
         swi     #0x9ffff0
-        mov     pc, lr
+        ldmfd   sp!, {r7, pc}
 
 #elif __LINUX_ARM_ARCH__ < 6