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Date:   Wed, 16 Nov 2022 15:16:10 -0500
From:   Steven Rostedt <rostedt@goodmis.org>
To:     "Joel Fernandes (Google)" <joel@joelfernandes.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
Subject: Re: [PATCH RFC] kexec: Freeze processes before kexec
Message-ID: <20221116151610.7294a9e8@gandalf.local.home>
In-Reply-To: <20221116195624.124092-1-joel@joelfernandes.org>
References: <20221116195624.124092-1-joel@joelfernandes.org>
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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.

-- Steve


> +
>  		kexec_in_progress = true;
>  		kernel_restart_prepare("kexec reboot");
>  		migrate_to_reboot_cpu();