Re: [Qemu-devel] [PATCH] linux-user/signal.c: Generate opcode data for restorer in setup_rt_frame

[Chen Gang]

Hello All:

Please help check this patch when you have time.

After this patch, we can let gcc testsuite cleanup-10 run successfully.

Next, I shall continue to implement floating point instructions: remove
(u)int64_to_float64 from fdouble implementation.


Thanks.

On 3/15/16 05:51, address@hidden wrote:
> From: Chen Gang <address@hidden>
> 
> 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 <address@hidden>
> ---
>  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;
>      }
>      env->pc = (unsigned long) ka->_sa_handler;
>      env->regs[TILEGX_R_SP] = (unsigned long) frame;
> 

-- 
Chen Gang (陈刚)

Managing Natural Environments is the Duty of Human Beings.