From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Tosatti <mtosatti@redhat.com>
Subject: [patch 0/2] fix lapic_timer_advance_ns guest triggerable unlimited delays
Date: Mon, 20 Jun 2016 22:28:01 -0300
Message-ID: <20160621012801.145630514@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>,
	Radim Krcmar <rkrcmar@redhat.com>,
	Alan Jenkins <alan.christopher.jenkins@gmail.com>
To: kvm@vger.kernel.org
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The host timer which emulates the guest LAPIC TSC deadline
timer has its expiration diminished by lapic_timer_advance_ns
nanoseconds. Therefore if, at wait_lapic_expire, a difference
larger than lapic_timer_advance_ns is encountered, delay at most
lapic_timer_advance_ns.

This fixes a problem where the guest can cause the host
to delay for large amounts of time.

Thanks to Alan Jenkins for reporting.