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Date:   Wed, 17 Aug 2022 19:09:26 -0300
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Subject: Re: [PATCH v2 10/13] EDAC/altera: Skip the panic notifier if kdump is
 loaded
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To:     Borislav Petkov <bp@alien8.de>
Cc:     pmladek@suse.com, Dinh Nguyen <dinguyen@kernel.org>,
        Tony Luck <tony.luck@intel.com>, akpm@linux-foundation.org,
        bhe@redhat.com, kexec@lists.infradead.org,
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        tglx@linutronix.de, vgoyal@redhat.com, vkuznets@redhat.com,
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From:   "Guilherme G. Piccoli" <gpiccoli@igalia.com>
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On 17/08/2022 19:00, Borislav Petkov wrote:
> On Wed, Aug 17, 2022 at 06:56:11PM -0300, Guilherme G. Piccoli wrote:
>> But do you agree that currently, in case of a kdump, that information
>> *is not collected*, with our without my patch?
> 
> If for some reason that panic notifier does not get run before kdump,
> then that's a bug and that driver should not use a panic notifier to log
> hw errors in the first place.
> 

Indeed, the notifiers don't run before kdump by default, in a conscious
decision of the kdump maintainers.

You might be right, in the sense that maybe the edac error handler
shouldn't run as a panic notifier. Let's see if Tony / Dinh can chime in
on that discussion - we could move it to run in the kexec event as well,
so it'd always run before a kdump, but maybe the risk it offers during
panic time is not worth.

Again - a matter of a trade-off, a good compromise must be agreed by all
parties (kdump maintainers are usually extremely afraid of taking risks
to not break kdump).

Cheers!