Re: [syzbot] WARNING in kvm_mmu_uninit_tdp_mmu (2)

[Maxim Levitsky]

On Thu, 2022-04-28 at 19:22 +0200, Paolo Bonzini wrote:
> On 4/28/22 17:32, Sean Christopherson wrote:
> > On Tue, Apr 26, 2022, Maxim Levitsky wrote:
> > > I can reproduce this in a VM, by running and CTRL+C'in my ipi_stress test,
> > 
> > Can you post your ipi_stress test?  I'm curious to see if I can repro, and also
> > very curious as to what might be unique about your test.  I haven't been able to
> > repro the syzbot test, nor have I been able to repro by killing VMs/tests.
> 
> Did you test with CONFIG_PREEMPT=y?

yes, I test with CONFIG_PREEMPT but I only enabled it a day ago,
I think I had seen this warning before, but could bit, I'll check
if that fails without CONFIG_PREEMPT as well.


What I recently changed, is that I enabled lockdep and related settings
on all my machines and VMs, I enabled CONFIG_PREEMPT, and I also
switched to tdp_mmu on all systems.

Bugs are biting but it is better this way, especially to weed out
the last bugs of my nested avic code :)

Best regards,
	Maxim Levitsky


> 
> (BTW, the fact that it reproduces under 5.17 is a mixed blessing, 
> because it means that we can analyze/stare at a simpler codebase).
> 
> Paolo
>