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Subject: Re: [PATCH] KVM:Hyper-V reduce one kvm_write_guest operation
To: Rhett Rhett <rhett.kernel@gmail.com>
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From: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <2ee6e3c6-f1c1-a5e4-a2ca-934f3414f3a9@redhat.com>
Date: Wed, 20 Dec 2017 10:45:02 +0100
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On 20/12/2017 10:33, Rhett Rhett wrote:
> tsc_sequence  had been set to 0 before,  so the tsc page won't function.
> guest has no chance to read tsc page before the last write.
> 

kvm_write_guest is not atomic.  The guest can see a non-zero sequence
before the other fields have been set.

Paolo