From abd5abc58c5d4c9bd23427b0998a44eb87ed47a2 Mon Sep 17 00:00:00 2001 From: Catherine Ho Date: Fri, 15 Feb 2019 09:56:38 +0000 Subject: [PATCH] target/arm: Fix int128_make128 lo, hi order in paired_cmpxchg64_be The lo,hi order is different from the comments. And in commit 1ec182c33379 ("target/arm: Convert to HAVE_CMPXCHG128"), it changes the original code logic. So just restore the old code logic before this commit: do_paired_cmpxchg64_be(): cmpv = int128_make128(env->exclusive_high, env->exclusive_val); newv = int128_make128(new_hi, new_lo); This fixes a bug that would only be visible for big-endian AArch64 guest code. Fixes: 1ec182c33379 ("target/arm: Convert to HAVE_CMPXCHG128") Signed-off-by: Catherine Ho Reviewed-by: Richard Henderson Message-id: 1548985244-24523-1-git-send-email-catherine.hecx@gmail.com [PMM: added note that bug only affects BE guests] Signed-off-by: Peter Maydell --- target/arm/helper-a64.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/target/arm/helper-a64.c b/target/arm/helper-a64.c index 101fa6d3ea..70850e564d 100644 --- a/target/arm/helper-a64.c +++ b/target/arm/helper-a64.c @@ -583,8 +583,8 @@ uint64_t HELPER(paired_cmpxchg64_be)(CPUARMState *env, uint64_t addr, * High and low need to be switched here because this is not actually a * 128bit store but two doublewords stored consecutively */ - Int128 cmpv = int128_make128(env->exclusive_val, env->exclusive_high); - Int128 newv = int128_make128(new_lo, new_hi); + Int128 cmpv = int128_make128(env->exclusive_high, env->exclusive_val); + Int128 newv = int128_make128(new_hi, new_lo); Int128 oldv; uintptr_t ra = GETPC(); uint64_t o0, o1; -- 2.42.0