Re: [PATCH v4 3/4] MIPS: Return earlier in die() if notify_die() returns NOTIFY_STOP

[Tiezhu Yang]

On 08/20/2023 04:53 PM, Huacai Chen wrote:
> Hi, Tiezhu,
>
> On Sun, Aug 20, 2023 at 7:21 AM Tiezhu Yang <yangtiezhu@xxxxxxxxxxx> 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@xxxxxxxxxxx>
> > Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
> > ---
> >  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 == 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 != 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.

No, it can return if (ret == NOTIFY_STOP), so die() is a return
function now, please see objdump -d arch/mips/kernel/traps.o.

Thanks,
Tiezhu