Re: [PATCH 1/2] nmi: Export CPU backtrace APIs for loadable modules

From: Guenter Roeck

Date: Thu Aug 06 2026 - 17:43:32 EST


On Thu, Jul 30, 2026 at 03:00:21PM -0700, Mayank Rungta wrote:
> From: Mayank Rungta <mrungta@xxxxxxxxxx>
>
> Currently, CPU backtrace functions cannot be called from loadable
> modules because the underlying helper arch_trigger_cpumask_backtrace()
> is not exported.
>
> Instead of exporting arch_trigger_cpumask_backtrace() individually
> across every supported architecture, introduce and export a common
> helper, cpumask_backtrace(), in lib/nmi_backtrace.c. Update the four
> inline CPU backtrace macros in include/linux/nmi.h to route through this
> centralized helper.
>
> Signed-off-by: Mayank Rungta <mrungta@xxxxxxxxxx>
> Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx>

Just to give an update: I'd love to apply this and the next patch of the
series, but I can not do wo without formal Ack from a maintainer (I did
that once and got burned for it, so it won't happen again).

I'll send an Ack to the next patch of the series, in case someone else
wants to pick it up.

Guenter