Re: [PATCH v5] panic: add panic_force_cpu= parameter to redirect panic to a specific CPU

Steven Rostedt
2026-01-08T21:00:33Z

On Thu, 8 Jan 2026 22:36:12 +0200
Pnina Feder <pnina.feder@mobileye.com> wrote:

First, new versions of a patch or patch set should *always* be a new thread
and not a reply to the old version. That makes it much harder on
maintainers to see a new series.

> If the specified CPU is invalid, offline, or a panic is already in
> progress on another CPU, the redirection is skipped and panic continues
> on the current CPU.
>
> Changes since v4:
> - Make IPI delivery an overridable weak function (panic_smp_redirect_cpu)
> so architectures can use NMI where available
> - Add declaration on include/linux/smp.h alongside other panic SMP functions
> - Add warning to documentation about reduced reliability
> - Address review comments from Andrew Morton (remove unnecessary cast,
> add missing kernel-doc parameters)
>
> Signed-off-by: Pnina Feder <pnina.feder@mobileye.com>
> ---

The "Changes since" line should always be below the '---' otherwise it gets
pulled into the git log and the maintainer needs to manually delete it
(which is annoying).

Also, it is helpful to add a link to the previous version.

> Signed-off-by: Pnina Feder <pnina.feder@mobileye.com>
> ---
Changes since v4: https://lore.kernel.org/all/20260107215659.3619730-1-pnina.feder@mobileye.com/
- Make IPI delivery an overridable weak function (panic_smp_redirect_cpu)
so architectures can use NMI where available
- Add declaration on include/linux/smp.h alongside other panic SMP functions
- Add warning to documentation about reduced reliability
- Address review comments from Andrew Morton (remove unnecessary cast,
add missing kernel-doc parameters)

This provides the continuity between versions without having to be replies
of older versions.

-- Steve