openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

arm: KVM: Disable virtual timer even if the guest is not using it 

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>
This commit is contained in:
Marc Zyngier 2015-09-16 16:18:59 +01:00
parent c4cbba9fa0
commit 688bc577ac
1 changed files with 4 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
arch/arm/kvm/interrupts_head.S
View File

@ -515,8 +515,7 @@ 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
@ -529,6 +528,9 @@ 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)