Re: [PATCH 6/7] linux-user/nios2: Use QEMU_ESIGRETURN from do_rt_sigreturn

[Peter Maydell]

On Sun, 20 Mar 2022 at 16:06, Richard Henderson
<richard.henderson@linaro.org> wrote:
>
> Drop the kernel-specific "pr2" code structure and use
> the qemu-specific error return value.
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  linux-user/nios2/signal.c | 10 +++-------
>  1 file changed, 3 insertions(+), 7 deletions(-)
>
> diff --git a/linux-user/nios2/signal.c b/linux-user/nios2/signal.c
> index 133bc05673..4442974001 100644
> --- a/linux-user/nios2/signal.c
> +++ b/linux-user/nios2/signal.c
> @@ -77,8 +77,7 @@ static void rt_setup_ucontext(struct target_ucontext *uc, 
> CPUNios2State *env)
>      __put_user(env->regs[R_SP], &gregs[28]);
>  }
>
> -static int rt_restore_ucontext(CPUNios2State *env, struct target_ucontext 
> *uc,
> -                               int *pr2)
> +static int rt_restore_ucontext(CPUNios2State *env, struct target_ucontext 
> *uc)
>  {
>      int temp;
>      unsigned long *gregs = uc->tuc_mcontext.gregs;
> @@ -128,8 +127,6 @@ static int rt_restore_ucontext(CPUNios2State *env, struct 
> target_ucontext *uc,
>      __get_user(env->regs[R_SP], &gregs[28]);
>
>      target_restore_altstack(&uc->tuc_stack, env);
> -
> -    *pr2 = env->regs[2];
>      return 0;
>  }
>
> @@ -191,7 +188,6 @@ long do_rt_sigreturn(CPUNios2State *env)
>      abi_ulong frame_addr = env->regs[R_SP];
>      struct target_rt_sigframe *frame;
>      sigset_t set;
> -    int rval;
>
>      if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1)) {
>          goto badframe;
> @@ -200,12 +196,12 @@ long do_rt_sigreturn(CPUNios2State *env)
>      target_to_host_sigset(&set, &frame->uc.tuc_sigmask);
>      set_sigmask(&set);
>
> -    if (rt_restore_ucontext(env, &frame->uc, &rval)) {
> +    if (rt_restore_ucontext(env, &frame->uc)) {
>          goto badframe;
>      }
>
>      unlock_user_struct(frame, frame_addr, 0);
> -    return rval;
> +    return -QEMU_ESIGRETURN;
>
>  badframe:
>      unlock_user_struct(frame, frame_addr, 0);

Don't you also need to return -QEMU_ESIGRETURN in the badframe
error-handling case? The other guest architecture implementations
of do_sigreturn seem to do that.

thanks
-- PMM