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From: John Ogness <john.ogness@linutronix.de>
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To: Carlos Bilbao <carlos.bilbao.osdev@gmail.com>, carlos.bilbao@kernel.org,
 tglx@linutronix.de, seanjc@google.com, jan.glauber@gmail.com
Cc: bilbao@vt.edu, pmladek@suse.com, akpm@linux-foundation.org,
 jani.nikula@intel.com, linux-kernel@vger.kernel.org,
 gregkh@linuxfoundation.org, takakura@valinux.co.jp
Subject: Re: [PATCH v2 2/2] x86/panic: Add x86_panic_handler as default
 post-panic behavior
In-Reply-To: <781ef1d7-f9c6-4a15-b94d-c735e83e7d01@gmail.com>
References: <20250428215952.1332985-1-carlos.bilbao@kernel.org>
 <20250428215952.1332985-3-carlos.bilbao@kernel.org>
 <84ldri7vv0.fsf@jogness.linutronix.de>
 <781ef1d7-f9c6-4a15-b94d-c735e83e7d01@gmail.com>
Date: Wed, 30 Apr 2025 10:04:05 +0206
Message-ID: <84bjseozci.fsf@jogness.linutronix.de>
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On 2025-04-29, Carlos Bilbao <carlos.bilbao.osdev@gmail.com> wrote:
>> I see no reason why you don't just use safe_halt() as your panic
>> handler.
>
> Yes, in my original implementation I simply used halt, but I was
> trying to be cautious in case any remaining messages hadn't flushed. I
> wonder, can we be certain that, as you said, all output (e.g., a
> backtrace) has already been displayed on screen at this point? I'm not
> sure.

Well, without this series, the kernel goes into an infinite loop. So if
the messages are not all out, they won't magically appear during the
infinite loop either.

John