Re: [regression] suspend stress test stalls within 30 minutes

[Dave Hansen <dave.hansen@intel.com>]

On 5/14/24 06:17, Kalle Valo wrote:
> The kernel we use in our ath11k testing has almost all kernel debug
> features enabled so I decided disable all of them, which unsurprisingly
> also fixed my suspend problems. So maybe this is something which happens
> only when MITIGATION_IBRS_ENTRY and some debug option from 'Kernel
> hacking' are both enabled?

I had my money on DEBUG_ENTRY, but it doesn't look like you ever had it
enabled.

I've got basically two theories:

One, the IBRS value is getting mucked up somewhere, either that %r15
value is getting stepped on or the per-cpu value is corrupt and the
WRMSR #GP's, causing the hang.

Two, IBRS_{ENTER,EXIT} is called in a "wrong" context somewhere.  Either
it is clobbering something it shouldn't or it is assuming something is
in place that is not (like a valid stack).

But the whole "'sudo shutdown -h now' then suspend somehow immediately
unstalls" thing is really perplexing.  I hope Pawan has some ideas.