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Message-ID: <d1e4eaba-2dcd-ec08-4e23-98ab8ea6c37b@redhat.com>
Date:   Thu, 28 Apr 2022 19:22:43 +0200
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Subject: Re: [syzbot] WARNING in kvm_mmu_uninit_tdp_mmu (2)
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To:     Sean Christopherson <seanjc@google.com>,
        Maxim Levitsky <mlevitsk@redhat.com>
Cc:     syzbot <syzbot+a8ad3ee1525a0c4b40ec@syzkaller.appspotmail.com>,
        bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com,
        jmattson@google.com, joro@8bytes.org, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, mingo@redhat.com,
        syzkaller-bugs@googlegroups.com, tglx@linutronix.de,
        vkuznets@redhat.com, wanpengli@tencent.com, x86@kernel.org
References: <00000000000082452505dd503126@google.com>
 <13b3235ef66f22475fd4059df95ad0144548ccd1.camel@redhat.com>
 <YmqzoFqdmH1WuPv0@google.com>
From:   Paolo Bonzini <pbonzini@redhat.com>
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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?

(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