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

[Ira Weiny]

Jonathan Cameron wrote:
> On Wed, 14 Feb 2024 17:33:18 -0500
> Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:
> 
> > On Wed, 14 Feb 2024 14:19:19 -0800
> > Ira Weiny <ira.weiny@xxxxxxxxx> wrote:
> > 
> > > > > Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> 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!
> > > > >   
> > 
> > I may be like Jon Corbet predicting RT will land in mainline if I do.
> > 
> > -- Steve
> > 
> 
> 
> Agreed. Don't wait on printk fixes landing. (Well unless you are sure
> it's the year of the Linux desktop.) Reverting is fine for 6.8
> if you and Dan feel it's unwise to take this forwards (all the distros
> will backport it anyway and 6.8 isn't an LTS so no great rush)
> so fine to just queue it up again for 6.9 with this fix.
> 
> As Steve said, tp_printk is a hack (a very useful one) and
> hopefully no one runs it in production.

OMG...  I did not realize what tp_printk() was exactly.  I should have
looked closer.

Do we have evidence of its use in production?

I would love to not have to revert/respin,
Ira