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Date: Thu, 4 Jan 2024 09:07:56 -0800
From: Andi Kleen <ak@linux.intel.com>
To: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>,
	Sean Christopherson <seanjc@google.com>,
	Like Xu <like.xu@linux.intel.com>,
	Kan Liang <kan.liang@linux.intel.com>,
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	kvm@vger.kernel.org, Breno Leitao <leitao@debian.org>,
	Arnaldo Carvalho de Melo <acme@kernel.org>,
	Ingo Molnar <mingo@redhat.com>
Subject: Re: [BUG] Guest OSes die simultaneously (bisected)
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In-Reply-To: <b2775ea5-20c9-4dff-b4b1-bbb212065a22@paulmck-laptop>

> My (completely random) guess is that there is some rare combination
> of events that causes this code to fail.  If so, is it feasible to
> construct a test that makes this rare combination of events less rare,
> so that similar future bugs are caught more quickly?

Yes, I tested something similar before. What you need is create lots of 
PMIs with perf (running perf top should be enough) and a workload that creates
lots of exits in a guest (e.g. running fio on a virtio device). This 
will stress test this particular path.

-Andi