3.13.11-ckt29 -stable review patch.  If anyone has any objections, please let 
me know.

------------------

From: Marc Zyngier <marc.zyng...@arm.com>

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 <christoffer.d...@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyng...@arm.com>
Signed-off-by: Kamal Mostafa <ka...@canonical.com>
---
 arch/arm64/kvm/hyp.S | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S
index 3b47c36..a1621ff 100644
--- a/arch/arm64/kvm/hyp.S
+++ b/arch/arm64/kvm/hyp.S
@@ -485,8 +485,6 @@ CPU_BE(     rev     w5, w5 )
        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
 
@@ -494,6 +492,9 @@ CPU_BE(     rev     w5, w5 )
        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
-- 
1.9.1

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