Subject: Re: [PATCH 1/3] panic: Disable crash_kexec_post_notifiers if kdump is not available

From: [email-masked] (Eric W. Biederman)
Date: Fri, 10 Jul 2015 08:41:28 -0500

Hidehiro Kawai <[email-masked]> writes:

> You can call panic notifiers and kmsg dumpers before kdump by
> specifying "crash_kexec_post_notifiers" as a boot parameter.
> However, it doesn't make sense if kdump is not available.  In that
> case, disable "crash_kexec_post_notifiers" boot parameter so that
> you can't change the value of the parameter.

Nacked-by: "Eric W. Biederman" <[email-masked]>

You are confusing kexec on panic and CONFIG_CRASH_DUMP
which is about the tools for reading the state of the previous kernel.

Eric

> Signed-off-by: Hidehiro Kawai <[email-masked]>
> Cc: Andrew Morton <[email-masked]>
> Cc: Eric Biederman <[email-masked]>
> Cc: Vivek Goyal <[email-masked]>
> ---
>  kernel/panic.c |    2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/kernel/panic.c b/kernel/panic.c
> index 04e91ff..5252331 100644
> --- a/kernel/panic.c
> +++ b/kernel/panic.c
> @@ -502,12 +502,14 @@ __visible void __stack_chk_fail(void)
>  core_param(pause_on_oops, pause_on_oops, int, 0644);
>  core_param(panic_on_warn, panic_on_warn, int, 0644);
>  
> +#ifdef CONFIG_CRASH_DUMP
>  static int __init setup_crash_kexec_post_notifiers(char *s)
>  {
>  	crash_kexec_post_notifiers = true;
>  	return 0;
>  }
>  early_param("crash_kexec_post_notifiers", setup_crash_kexec_post_notifiers);
> +#endif
>  
>  static int __init oops_setup(char *s)
>  {