Being able to set a global offset isn't enough.
With NV, we also need to a per-vcpu, per-timer offset (for example,
CNTVCT_EL0 being offset by CNTVOFF_EL2).
Use a similar method as the VM-wide offset to have a timer point
to the shadow register that contains the offset value.
Reviewed-by: Colton Lewis <coltonlewis@xxxxxxxxxx>
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
---
arch/arm64/kvm/arch_timer.c | 13 ++++++++++---
arch/arm64/kvm/hyp/include/hyp/switch.h | 2 ++
include/kvm/arm_arch_timer.h | 5 +++++
3 files changed, 17 insertions(+), 3 deletions(-)
diff --git a/arch/arm64/kvm/arch_timer.c b/arch/arm64/kvm/arch_timer.c
index d3a7902269c1..b87bf182af33 100644
--- a/arch/arm64/kvm/arch_timer.c
+++ b/arch/arm64/kvm/arch_timer.c
@@ -89,10 +89,17 @@ u64 timer_get_cval(struct arch_timer_context *ctxt)
static u64 timer_get_offset(struct arch_timer_context *ctxt)
{
- if (ctxt && ctxt->offset.vm_offset)
- return *ctxt->offset.vm_offset;
+ u64 offset = 0;
- return 0;
+ if (!ctxt)
+ return 0;
+
+ if (ctxt->offset.vm_offset)
+ offset += *ctxt->offset.vm_offset;
+ if (ctxt->offset.vcpu_offset)
+ offset += *ctxt->offset.vcpu_offset;
+
+ return offset;
}
static void timer_set_ctl(struct arch_timer_context *ctxt, u32 ctl)
diff --git a/arch/arm64/kvm/hyp/include/hyp/switch.h b/arch/arm64/kvm/hyp/include/hyp/switch.h
index 9954368f639d..d07cbc313889 100644
--- a/arch/arm64/kvm/hyp/include/hyp/switch.h
+++ b/arch/arm64/kvm/hyp/include/hyp/switch.h
@@ -353,6 +353,8 @@ static bool kvm_hyp_handle_cntpct(struct kvm_vcpu *vcpu)
if (ctxt->offset.vm_offset)
val -= *kern_hyp_va(ctxt->offset.vm_offset);
+ if (ctxt->offset.vcpu_offset)
+ val -= *kern_hyp_va(ctxt->offset.vcpu_offset);
vcpu_set_reg(vcpu, kvm_vcpu_sys_get_rt(vcpu), val);
__kvm_skip_instr(vcpu);
diff --git a/include/kvm/arm_arch_timer.h b/include/kvm/arm_arch_timer.h
index f093ea9f540d..209da0c2ac9f 100644
--- a/include/kvm/arm_arch_timer.h
+++ b/include/kvm/arm_arch_timer.h
@@ -29,6 +29,11 @@ struct arch_timer_offset {
* structure. If NULL, assume a zero offset.
*/
u64 *vm_offset;
+ /*
+ * If set, pointer to one of the offsets in the vcpu's sysreg
+ * array. If NULL, assume a zero offset.
+ */
+ u64 *vcpu_offset;
};
struct arch_timer_vm_data {
--
2.34.1
