From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH] target-i386: clear guest TSC on reset
Date: Thu, 05 Dec 2013 17:38:33 +0100
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Cc: Fernando Luis Vazquez Cao <fernando_b1@lab.ntt.co.jp>,
	Gleb Natapov <gleb@kernel.org>,
	Will Auld <will.auld@intel.com>, qemu-devel@nongnu.org,
	kvm@vger.kernel.org
To: Marcelo Tosatti <mtosatti@redhat.com>
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Il 05/12/2013 17:17, Marcelo Tosatti ha scritto:
>> > I agree it is a bit ugly, but in my testing QEMU seemed to loop over all
>> > the VCPUS fast enough for the kernel side kvm_write_tsc() to do a
>> > reasonable job of matching the offsets (the Linux guest did not mark
>> > the TSC unstable due to the TSCs being unsynchronized). Am I missing
>> > something?
> Right, modern kernels (see kvm_write_tsc) perform synchronization, so in
> theory the "KVM is yet unable to synchronize ..." code is not necessary
> anymore.
> 
> I vote for dropping the thing entirely.

If it can be dropped entirely, I certainly have no problem with starting
with a simple patch first.

Paolo