Re: [PATCH v2] acpi/ghes: Prevent sleeping with spinlock held

Ira Weiny
2024-02-14T22:19:27Z

Jonathan Cameron wrote:
> On Wed, 14 Feb 2024 10:23:10 -0500
> Steven Rostedt <rostedt@goodmis.org> wrote:
>
> > On Wed, 14 Feb 2024 12:11:53 +0000
> > Jonathan Cameron <Jonathan.Cameron@huawei.com> wrote:
> >
> > > So I'm thinking this is a won't fix - wait for the printk rework to land and
> > > assume this will be resolved as well?
> >
> > That pretty much sums up what I was about to say ;-)
> >
> > tp_printk is more of a hack and not to be used sparingly. With the right
> > trace events it can hang the machine.
> >
> > So, you can use your internal patch locally, but I would recommend waiting
> > for the new printk changes to land.

Steven, Do you think that will land in 6.9?

> >
> > I'm really hoping that will be soon!
> >
> > -- Steve
>
> Thanks Steve,
>
> Ira's fix is needed for other valid locking reasons - this was 'just another'
> lock debugging report that came up whilst testing it.
>
> For this patch (not a potential additional one that we aren't going to do ;)
>
> Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Jonathan,

Again thanks for the testing! However, Dan and I just discussed this and
he has an uneasy feeling about going forward with this for 6.8 final.

If we revert the following patch I can squash this fix and wait for the
tp_printk() fix to land in 6.9 and resubmit.

Dan here is the patch which backs out the actual bug:

Fixes: 671a794c33c6 ("acpi/ghes: Process CXL Component Events")

Thanks everyone,
Ira