From 38ea1f358b3b7dd4b965ef992894b5857471dc45 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Tue, 21 Jan 2014 14:03:58 +0100 Subject: [PATCH] s390/32bit: fix cmpxchg64 Fix broken inline assembly contraints for cmpxchg64 on 32bit. Fixes this crash: specification exception: 0006 [#1] SMP CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.13.0 #4 task: 005a16c8 ti: 00592000 task.ti: 00592000 Krnl PSW : 070ce000 8029abd6 (lockref_get+0x3e/0x9c) ... Krnl Code: 8029abcc: a71a0001 ahi %r1,1 8029abd0: 1852 lr %r5,%r2 #8029abd2: bb40f064 cds %r4,%r0,100(%r15) >8029abd6: 1943 cr %r4,%r3 8029abd8: 1815 lr %r1,%r5 Call Trace: ([<0000000078e01870>] 0x78e01870) [<000000000021105a>] sysfs_mount+0xd2/0x1c8 [<00000000001b551e>] mount_fs+0x3a/0x134 [<00000000001ce768>] vfs_kern_mount+0x44/0x11c [<00000000001ce864>] kern_mount_data+0x24/0x3c [<00000000005cc4b8>] sysfs_init+0x74/0xd4 [<00000000005cb5b4>] mnt_init+0xe0/0x1fc [<00000000005cb16a>] vfs_caches_init+0xb6/0x14c [<00000000005be794>] start_kernel+0x318/0x33c [<000000000010001c>] _stext+0x1c/0x80 Reported-by: Mike Frysinger Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky --- arch/s390/include/asm/cmpxchg.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/s390/include/asm/cmpxchg.h b/arch/s390/include/asm/cmpxchg.h index 0f636cbdf342..4236408070e5 100644 --- a/arch/s390/include/asm/cmpxchg.h +++ b/arch/s390/include/asm/cmpxchg.h @@ -185,11 +185,12 @@ static inline unsigned long long __cmpxchg64(void *ptr, { register_pair rp_old = {.pair = old}; register_pair rp_new = {.pair = new}; + unsigned long long *ullptr = ptr; asm volatile( " cds %0,%2,%1" - : "+&d" (rp_old), "=Q" (ptr) - : "d" (rp_new), "Q" (ptr) + : "+d" (rp_old), "+Q" (*ullptr) + : "d" (rp_new) : "memory", "cc"); return rp_old.pair; }