Re: [syzbot] WARNING in static_key_slow_try_dec (2)

[Sean Christopherson]

On Tue, Oct 12, 2021, Sean Christopherson wrote:
> On Sun, Oct 10, 2021, Tetsuo Handa wrote:
> > Hello.
> > 
> > Commit 4547700a4d190ac4 ("KVM: x86: Consolidate APIC base RESET initialization code")
> 
> That's definitely where the error was made visible,

I take that back, the bug was likely visible even before the redundant vendor code
was dropped.  Doesn't change the fix in any way though.

> but commit 421221234ada ("KVM: x86: Open code necessary bits of
> kvm_lapic_set_base() at vCPU RESET") is the real culprit.  I'll send a patch
> later today.  I'm leaning toward a partial revert with some extra comments.
> 
> Thanks for the debug!  I was having trouble reproducing the syzbot report.