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Date: Thu, 1 Feb 2024 09:01:34 -0800
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Subject: Re: [PATCH] KVM: selftests: Compare wall time from xen shinfo against KVM_GET_CLOCK
From: Sean Christopherson <seanjc@google.com>
To: kvm@vger.kernel.org, Paolo Bonzini <pbonzini@redhat.com>, 
	Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>, Jan Richter <jarichte@redhat.com>, linux-kernel@vger.kernel.org
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On Tue, Jan 30, 2024, Sean Christopherson wrote:
> On Thu, 11 Jan 2024 14:59:01 +0100, Vitaly Kuznetsov wrote:
> > xen_shinfo_test is observed to be flaky failing sporadically with
> > "VM time too old". With min_ts/max_ts debug print added:
> > 
> > Wall clock (v 3269818) 1704906491.986255664
> > Time info 1: v 1282712 tsc 33530585736 time 14014430025 mul 3587552223 shift 4294967295 flags 1
> > Time info 2: v 1282712 tsc 33530585736 time 14014430025 mul 3587552223 shift 4294967295 flags 1
> > min_ts: 1704906491.986312153
> > max_ts: 1704906506.001006963
> > ==== Test Assertion Failure ====
> >   x86_64/xen_shinfo_test.c:1003: cmp_timespec(&min_ts, &vm_ts) <= 0
> >   pid=32724 tid=32724 errno=4 - Interrupted system call
> >      1	0x00000000004030ad: main at xen_shinfo_test.c:1003
> >      2	0x00007fca6b23feaf: ?? ??:0
> >      3	0x00007fca6b23ff5f: ?? ??:0
> >      4	0x0000000000405e04: _start at ??:?
> >   VM time too old
> > 
> > [...]
> 
> Applied to kvm-x86 selftests.  David, please holler if you disagree with
> any of the changes.  They look sane to me, but clock stuff ain't my forte.
> 
> Thanks!
> 
> [1/1] KVM: selftests: Compare wall time from xen shinfo against KVM_GET_CLOCK
>       https://github.com/kvm-x86/linux/commit/a0868e7c5575

FYI, I've dropped this as it looks like there will be a new version.