| [Qemu-ppc] [PATCH 1/1] target-ppc, tcg: fix usermode segfault with pthread |
| |
| From: Sam Bobroff |
| Subject: [Qemu-ppc] [PATCH 1/1] target-ppc, tcg: fix usermode segfault with pthread_create() |
| Date: Mon, 30 Jan 2017 16:08:07 +1100 |
| Programs run under qemu-ppc64 on an x86_64 host currently segfault |
| if they use pthread_create() due to the adjustment made to the NIP in |
| commit bd6fefe71cec5a0c7d2be4ac96307f25db56abf9. |
| |
| This patch changes cpu_loop() to set the NIP back to the |
| pre-incremented value before calling do_syscall(), which causes the |
| correct address to be used for the new thread and corrects the fault. |
| |
| Signed-off-by: Sam Bobroff <address@hidden> |
| |
| Upstream-Status: Backport |
| |
| --- |
| |
| linux-user/main.c | 4 +++- |
| 1 file changed, 3 insertions(+), 1 deletion(-) |
| |
| diff --git a/linux-user/main.c b/linux-user/main.c |
| index 30049581ef..b5dee01541 100644 |
| --- a/linux-user/main.c |
| +++ b/linux-user/main.c |
| @@ -1712,18 +1712,20 @@ void cpu_loop(CPUPPCState *env) |
| * in syscalls. |
| */ |
| env->crf[0] &= ~0x1; |
| + env->nip += 4; |
| ret = do_syscall(env, env->gpr[0], env->gpr[3], env->gpr[4], |
| env->gpr[5], env->gpr[6], env->gpr[7], |
| env->gpr[8], 0, 0); |
| if (ret == -TARGET_ERESTARTSYS) { |
| + env->nip -= 4; |
| break; |
| } |
| if (ret == (target_ulong)(-TARGET_QEMU_ESIGRETURN)) { |
| + env->nip -= 4; |
| /* Returning from a successful sigreturn syscall. |
| Avoid corrupting register state. */ |
| break; |
| } |
| - env->nip += 4; |
| if (ret > (target_ulong)(-515)) { |
| env->crf[0] |= 0x1; |
| ret = -ret; |