From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:36238 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750856AbbJMS3H (ORCPT ); Tue, 13 Oct 2015 14:29:07 -0400 Subject: Patch "arm: KVM: Disable virtual timer even if the guest is not using it" has been added to the 4.1-stable tree To: marc.zyngier@arm.com, gregkh@linuxfoundation.org Cc: , From: Date: Tue, 13 Oct 2015 11:21:01 -0700 Message-ID: <144476046122207@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled arm: KVM: Disable virtual timer even if the guest is not using it to the 4.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: arm-kvm-disable-virtual-timer-even-if-the-guest-is-not-using-it.patch and it can be found in the queue-4.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 688bc577ac42ae3d07c889a1f0a72f0b23763d58 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 16 Sep 2015 16:18:59 +0100 Subject: arm: KVM: Disable virtual timer even if the guest is not using it From: Marc Zyngier commit 688bc577ac42ae3d07c889a1f0a72f0b23763d58 upstream. When running a guest with the architected timer disabled (with QEMU and the kernel_irqchip=off option, for example), it is important to make sure the timer gets turned off. Otherwise, the guest may try to enable it anyway, leading to a screaming HW interrupt. The fix is to unconditionally turn off the virtual timer on guest exit. Signed-off-by: Marc Zyngier Signed-off-by: Greg Kroah-Hartman --- arch/arm/kvm/interrupts_head.S | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/arch/arm/kvm/interrupts_head.S +++ b/arch/arm/kvm/interrupts_head.S @@ -518,8 +518,7 @@ ARM_BE8(rev r6, r6 ) mrc p15, 0, r2, c14, c3, 1 @ CNTV_CTL str r2, [vcpu, #VCPU_TIMER_CNTV_CTL] - bic r2, #1 @ Clear ENABLE - mcr p15, 0, r2, c14, c3, 1 @ CNTV_CTL + isb mrrc p15, 3, rr_lo_hi(r2, r3), c14 @ CNTV_CVAL @@ -532,6 +531,9 @@ ARM_BE8(rev r6, r6 ) mcrr p15, 4, r2, r2, c14 @ CNTVOFF 1: + mov r2, #0 @ Clear ENABLE + mcr p15, 0, r2, c14, c3, 1 @ CNTV_CTL + @ Allow physical timer/counter access for the host mrc p15, 4, r2, c14, c1, 0 @ CNTHCTL orr r2, r2, #(CNTHCTL_PL1PCEN | CNTHCTL_PL1PCTEN) Patches currently in stable-queue which might be from marc.zyngier@arm.com are queue-4.1/arm-kvm-fix-incorrect-device-to-ipa-mapping.patch queue-4.1/arm-kvm-disable-virtual-timer-even-if-the-guest-is-not-using-it.patch