On Wed, Sep 16, 2015 at 04:58:06PM +0100, Marc Zyngier wrote: > 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. > > Cc: [email protected] > Signed-off-by: Marc Zyngier <[email protected]> > --- > arch/arm64/kvm/hyp.S | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S > index 6addf97..38f5434 100644 > --- a/arch/arm64/kvm/hyp.S > +++ b/arch/arm64/kvm/hyp.S > @@ -570,8 +570,6 @@ alternative_endif
The context confuses me; did you happen to base this on your VHE patches? > 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 > > @@ -579,6 +577,8 @@ alternative_endif > str x3, [x0, #VCPU_TIMER_CNTV_CVAL] > > 1: > + msr cntv_ctl_el0, xzr > + We could have a comment here, but ok. > // Allow physical timer/counter access for the host > mrs x2, cnthctl_el2 > orr x2, x2, #3 > -- > 2.1.4 > Otherwise: Reviewed-by: Christoffer Dall <[email protected]> _______________________________________________ kvmarm mailing list [email protected] https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
