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Date: Sat, 3 Jan 2026 10:29:27 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: Pnina Feder <pnina.feder@mobileye.com>
Cc: Petr Mladek <pmladek@suse.com>, Sergey Senozhatsky
 <senozhatsky@chromium.org>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] panic/kexec: Allow forcing panic execution on a
 specific CPU
Message-Id: <20260103102927.7add52a51ed0623c6e8bc729@linux-foundation.org>
In-Reply-To: <20260101123237.277411-1-pnina.feder@mobileye.com>
References: <20260101123237.277411-1-pnina.feder@mobileye.com>
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On Thu,  1 Jan 2026 14:32:37 +0200 Pnina Feder <pnina.feder@mobileye.com> wrote:

> Some platforms require panic handling to execute on a specific CPU
> for crash dump to work reliably. This may be due to firmware,
> interrupt routing, or platform-specific constraints where only one
> CPU is able to safely enter the crash kernel.
> 
> Add an optional configuration that allows redirecting panic execution
> to a designated target CPU before invoking kexec into the crash kernel.
> 
> When CONFIG_PANIC_FORCE_CPU is enabled, the initial panic CPU will
> forward the panic to the configured CPU using smp_call_function_single().
> If a panic is already in progress on another CPU, redirection is
> skipped and a warning is printed.

Requiring a recompile/reinstall isn't very user-friendly.  Is it
possible to do this with a kernel boot option?