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: stable@vger.kernel.org
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
mrc p15, 0, r2, c14, c3, 1 @ CNTV_CTL
str r2, [vcpu, #VCPU_TIMER_CNTV_CTL]
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
isb
mrrc p15, 3, rr_lo_hi(r2, r3), c14 @ CNTV_CVAL
mcrr p15, 4, r2, r2, c14 @ CNTVOFF
1:
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)
@ Allow physical timer/counter access for the host
mrc p15, 4, r2, c14, c1, 0 @ CNTHCTL
orr r2, r2, #(CNTHCTL_PL1PCEN | CNTHCTL_PL1PCTEN)