linux-kernel - Re: [PATCH] panic/kexec: Allow forcing panic execution on a specific CPU

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20260103102927.7add52a51ed0623c6e8bc729@linux-foundation.org>
Date: Sat, 3 Jan 2026 10:29:27 -0800
From: Andrew Morton <akpm@...ux-foundation.org>
To: Pnina Feder <pnina.feder@...ileye.com>
Cc: Petr Mladek <pmladek@...e.com>, Sergey Senozhatsky
 <senozhatsky@...omium.org>, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] panic/kexec: Allow forcing panic execution on a
 specific CPU

On Thu,  1 Jan 2026 14:32:37 +0200 Pnina Feder <pnina.feder@...ileye.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?