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Date:   Thu, 27 Jan 2022 13:47:34 -0300
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Subject: Re: [PATCH V4] panic: Move panic_print before kmsg dumpers
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To:     Baoquan He <bhe@redhat.com>, akpm@linux-foundation.org
Cc:     linux-kernel@vger.kernel.org, pmladek@suse.com, anton@enomsg.org,
        ccross@android.com, dyoung@redhat.com, feng.tang@intel.com,
        john.ogness@linutronix.de, keescook@chromium.org,
        kernel@gpiccoli.net, kexec@lists.infradead.org,
        rostedt@goodmis.org, senozhatsky@chromium.org, tony.luck@intel.com,
        vgoyal@redhat.com
References: <20220124203101.216051-1-gpiccoli@igalia.com>
 <20220126052246.GC2086@MiWiFi-R3L-srv>
From:   "Guilherme G. Piccoli" <gpiccoli@igalia.com>
In-Reply-To: <20220126052246.GC2086@MiWiFi-R3L-srv>
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On 26/01/2022 02:22, Baoquan He wrote:
> [...]
>>  	if (!_crash_kexec_post_notifiers) {
>> +		if (kexec_crash_loaded())
>> +			panic_print_sys_info(false);
>> +
> 
> Please reconsider this change. As I said in another thread, it's not
> suggested when adding any action before kdump switching and the action
> doesn't benefit kdump switching.
> 
> We don't oppose execute handling before kdump switching as long as
> it's executed conditionally. For those conditional extra handling and
> the followoing crash dumping's stability, it's not under kdump's care.
> 

Hi Baoquan, thanks for your review - I understand your concern, so let's
reconsider the change, as you suggest. The only thing is that the
specific bit that concerns you is not really a code added by the hereby
proposed patch, but it was in another patch I submitted, that reached
linux-next.

So, Andrew : can I ask you to please remove the following patch from
linux-next?

"panic: allow printing extra panic information on kdump"
https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=56439cb78293

(I'll also send this request in the original thread of the patch, for
completeness).

Baoquan: once it's removed from linux-next, I'll rework this proposed
patch and send a V5, hopefully a version that you consider more safe =)
Cheers,


Guilherme