Re: [PATCH v11 4/6] arm64: smp: Add arch support for backtrace using pseudo-NMI

[Doug Anderson]

Hi,

On Mon, Aug 28, 2023 at 10:23 PM Tomohiro Misono (Fujitsu)
<misono.tomohiro@xxxxxxxxxxx> wrote:
>
> > -----Original Message-----
> > Subject: [PATCH v11 4/6] arm64: smp: Add arch support for backtrace using
> > pseudo-NMI
> >
> > Enable arch_trigger_cpumask_backtrace() support on arm64. This enables
> > things much like they are enabled on arm32 (including some of the
> > funky logic around NR_IPI, nr_ipi, and MAX_IPI) but with the
> > difference that, unlike arm32, we'll try to enable the backtrace to
> > use pseudo-NMI.
> >
> > NOTE: this patch is a squash of the little bit of code adding the
> > ability to mark an IPI to try to use pseudo-NMI plus the little bit of
> > code to hook things up for kgdb. This approach was decided upon in the
> > discussion of v9 [1].
> >
> > This patch depends on commit 36759e343ff9 ("nmi_backtrace: allow
>
> Hi,
> Is this commit ID valid? I believe this commit is not included in the
> mainline yet. Other than this,
>  Reviewed-by: Misono Tomohiro <misono.tomohiro@xxxxxxxxxxx>

Ah, good call. I must have grabbed that git hash before the commit
moved from Andrew Morton's unstable branch to his stable branch. As
far as I can tell, it should be commit 8d539b84f1e3 ("nmi_backtrace:
allow excluding an arbitrary CPU"). ...at least that's what's in
linuxnext today. That also appears to match the commit hash in the
pull request that Andrew just sent to Linus [1].

I'll update the git hash and add your tag in v12, which I'm currently
aiming to send out tomorrow.

[1] https://lore.kernel.org/r/20230828225431.354d3d2d3b80ee5b88e65eb5@xxxxxxxxxxxxxxxxxxxx