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References: <20221116195624.124092-1-joel@joelfernandes.org> <20221116151610.7294a9e8@gandalf.local.home>
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From:   Joel Fernandes <joel@joelfernandes.org>
Date:   Wed, 16 Nov 2022 21:07:56 +0000
Message-ID: <CAEXW_YTu2-zM_Qmm5=giLoDvqEutMHFNxsi8Q2kT9axCgHFwEQ@mail.gmail.com>
Subject: Re: [PATCH RFC] kexec: Freeze processes before kexec
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     linux-kernel@vger.kernel.org, ribalda@google.com,
        zwisler@google.com, robdclark@gmail.com,
        Eric Biederman <ebiederm@xmission.com>,
        kexec@lists.infradead.org
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Hey Steve,

On Wed, Nov 16, 2022 at 8:15 PM Steven Rostedt <rostedt@goodmis.org> wrote:
>
> On Wed, 16 Nov 2022 19:56:24 +0000
> "Joel Fernandes (Google)" <joel@joelfernandes.org> wrote:
>
> > --- a/kernel/kexec_core.c
> > +++ b/kernel/kexec_core.c
> > @@ -1175,6 +1175,12 @@ int kernel_kexec(void)
> >       } else
> >  #endif
> >       {
> > +             error = freeze_processes();
> > +             if (error) {
> > +                     error = -EBUSY;
> > +                     goto Unlock;
> > +             }
>
> If this is the path of a kernel panic, do we really want to check the
> return error of freeze_processes()? We are panicing, there's not much more
> we can do.

I am OK with not checking the return of freeze_processes() and trying
to shut down anyway. Will re-spin after any other feedback.

Thanks,

 - Joel