[PATCH 6/6] openrisc: use scratch regs in atomic syscall

From: Jonas Bonn
Date: Tue May 08 2012 - 05:54:31 EST

The function sys_or1k_atomic was using call-saved registers without
restoring their value before returning. This is a faux pas: either
we need to restore their values or use scratch regs; the latter is
less code so that's the route this patch takes.

Thanks to David HennerstrÃm for doing most of the heavy-lifting in
tracking this one down.

Reported-by: Davd HennerstrÃm <david.hennerstrom@xxxxxxxxxxxxxxx>
Signed-off-by: Jonas Bonn <jonas@xxxxxxxxxxxx>
arch/openrisc/kernel/entry.S | 8 ++++----
1 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/openrisc/kernel/entry.S b/arch/openrisc/kernel/entry.S
index 6e61af8..ddfcaa8 100644
--- a/arch/openrisc/kernel/entry.S
+++ b/arch/openrisc/kernel/entry.S
@@ -1117,10 +1117,10 @@ ENTRY(sys_rt_sigreturn)
/* FIXME: This ignores r3 and always does an XCHG */
- l.lwz r30,0(r4)
- l.lwz r28,0(r5)
- l.sw 0(r4),r28
- l.sw 0(r5),r30
+ l.lwz r29,0(r4)
+ l.lwz r27,0(r5)
+ l.sw 0(r4),r27
+ l.sw 0(r5),r29
l.jr r9
l.or r11,r0,r0

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