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From: Marcelo Tosatti <mtosatti@redhat.com>
To: kvm@vger.kernel.org
Cc: Paolo Bonzini <pbonzini@redhat.com>,
	Radim Krcmar <rkrcmar@redhat.com>,
	Alan Jenkins <alan.christopher.jenkins@gmail.com>
Subject: [patch 0/2] fix lapic_timer_advance_ns guest triggerable unlimited delays
Date: Mon, 20 Jun 2016 22:28:01 -0300	[thread overview]
Message-ID: <20160621012801.145630514@redhat.com> (raw)

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.




             reply	other threads:[~2016-06-21  1:29 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-06-21  1:28 Marcelo Tosatti [this message]
2016-06-21  1:28 ` [patch 1/2] KVM: x86: move nsec_to_cycles from x86.c to x86.h Marcelo Tosatti
2016-06-21  1:28 ` [patch 2/2] KVM: LAPIC: cap __delay at lapic_timer_advance_ns Marcelo Tosatti
2016-06-21  1:33   ` [patch 2/2 V2] " Marcelo Tosatti
2016-06-21 12:13     ` Alan Jenkins
2016-06-21  7:53 ` [patch 0/2] fix lapic_timer_advance_ns guest triggerable unlimited delays Paolo Bonzini

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