On 3/29/16 06:17, Laurent Vivier wrote:
>> On 3/15/16 05:51, cheng...@emindsoft.com.cn wrote:
>>>
>>> Original implementation uses do_rt_sigreturn directly in host space,
>>> when a guest program is in unwind procedure in guest space, it will get
>>> an incorrect restore address, then causes unwind failure.
>>>
>>> Also cleanup the original incorrect indentation.
>>>
>>> Signed-off-by: Chen Gang <gang.chen.5...@gmail.com>
>>> ---
>>> linux-user/signal.c | 12 ++++++++++--
>>> 1 file changed, 10 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/linux-user/signal.c b/linux-user/signal.c
>>> index 919aa83..0e3b1c6 100644
>>> --- a/linux-user/signal.c
>>> +++ b/linux-user/signal.c
>>> @@ -5566,8 +5566,13 @@ struct target_rt_sigframe {
>>> unsigned char save_area[16]; /* caller save area */
>>> struct target_siginfo info;
>>> struct target_ucontext uc;
>>> + abi_ulong retcode[2];
>>> };
>>>
>>> +#define INSN_MOVELI_R10_139 0x00045fe551483000ULL /* { moveli r10, 139 }
>>> */
>>> +#define INSN_SWINT1 0x286b180051485000ULL /* { swint1 } */
>>> +
>>> +
>>> static void setup_sigcontext(struct target_sigcontext *sc,
>>> CPUArchState *env, int signo)
>>> {
>>> @@ -5643,9 +5648,12 @@ static void setup_rt_frame(int sig, struct
>>> target_sigaction *ka,
>>> __put_user(target_sigaltstack_used.ss_size,
>>> &frame->uc.tuc_stack.ss_size);
>>> setup_sigcontext(&frame->uc.tuc_mcontext, env, info->si_signo);
>>>
>>> - restorer = (unsigned long) do_rt_sigreturn;
>>> if (ka->sa_flags & TARGET_SA_RESTORER) {
>>> - restorer = (unsigned long) ka->sa_restorer;
>>> + restorer = (unsigned long) ka->sa_restorer;
>>> + } else {
>>> + __put_user(INSN_MOVELI_R10_139, &frame->retcode[0]);
>>> + __put_user(INSN_SWINT1, &frame->retcode[1]);
>>> + restorer = (unsigned long)frame->retcode;
>
> The address of retcode in host and guest can differ.
> You need something like:
>
> restorer = (unsigned long)(frame_addr + offsetof(struct
> target_rt_sigframe, retcode));
>
> I've experienced this on sh4 (see commit 2a0fa68)
>
OK, thanks. What you said above sounds reasonable to me. :-)
I shall send patch v2 for it (although tilegx is a pure 64-bit target,
with this patch, I guess, tilegx target should still run correctly under
32-bit host).
By the way, it looks that s390x and microblaze targets also have the
same issue.
Thanks.
--
Chen Gang (陈刚)
Managing Natural Environments is the Duty of Human Beings.
