From: Marc Zyngier Date: Wed, 16 Sep 2015 15:18:59 +0000 (+0100) Subject: arm64: KVM: Disable virtual timer even if the guest is not using it X-Git-Tag: v4.1.9~135 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=f283a20ab79c44af3e493cfbcc2550404d75c3b8;p=users%2Fjedix%2Flinux-maple.git arm64: KVM: Disable virtual timer even if the guest is not using it commit c4cbba9fa078f55d9f6d081dbb4aec7cf969e7c7 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. Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier Signed-off-by: Greg Kroah-Hartman --- diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S index 4dad27ba7d3d..64f9e60b31da 100644 --- a/arch/arm64/kvm/hyp.S +++ b/arch/arm64/kvm/hyp.S @@ -844,8 +844,6 @@ mrs x3, cntv_ctl_el0 and x3, x3, #3 str w3, [x0, #VCPU_TIMER_CNTV_CTL] - bic x3, x3, #1 // Clear Enable - msr cntv_ctl_el0, x3 isb @@ -853,6 +851,9 @@ str x3, [x0, #VCPU_TIMER_CNTV_CVAL] 1: + // Disable the virtual timer + msr cntv_ctl_el0, xzr + // Allow physical timer/counter access for the host mrs x2, cnthctl_el2 orr x2, x2, #3