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From:   Huacai Chen <chenhuacai@kernel.org>
Date:   Sun, 20 Aug 2023 16:53:14 +0800
Message-ID: <CAAhV-H5_3NeAEqiBgXqxwhUbTGRhEO0fL2bY4KCOJ6J=cf9Emw@mail.gmail.com>
Subject: Re: [PATCH v4 3/4] MIPS: Return earlier in die() if notify_die()
 returns NOTIFY_STOP
To:     Tiezhu Yang <yangtiezhu@loongson.cn>
Cc:     Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
        "Maciej W. Rozycki" <macro@orcam.me.uk>,
        linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org,
        loongson-kernel@lists.loongnix.cn
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Hi, Tiezhu,

On Sun, Aug 20, 2023 at 7:21=E2=80=AFAM Tiezhu Yang <yangtiezhu@loongson.cn=
> wrote:
>
> After the call to oops_exit(), it should not panic or execute
> the crash kernel if the oops is to be suppressed.
>
> Suggested-by: Maciej W. Rozycki <macro@orcam.me.uk>
> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
> ---
>  arch/mips/kernel/traps.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
> index 8e528a8..fd770dc 100644
> --- a/arch/mips/kernel/traps.c
> +++ b/arch/mips/kernel/traps.c
> @@ -412,6 +412,9 @@ void die(const char *str, struct pt_regs *regs)
>
>         oops_exit();
>
> +       if (ret =3D=3D NOTIFY_STOP)
> +               return;
> +
>         if (in_interrupt())
>                 panic("Fatal exception in interrupt");
>
> @@ -421,8 +424,7 @@ void die(const char *str, struct pt_regs *regs)
>         if (regs && kexec_should_crash(current))
>                 crash_kexec(regs);
>
> -       if (ret !=3D NOTIFY_STOP)
> -               make_task_dead(SIGSEGV);
> +       make_task_dead(SIGSEGV);
Then you call make_task_dead() at the end unconditionally, and die()
becomes a noreturn function again.

Huacai
>  }
>
>  extern struct exception_table_entry __start___dbe_table[];
> --
> 2.1.0
>