[PATCH v4 08/21] KVM: ARM64: Add reset and access handlers for PMXEVTYPER register

On 2015/12/1 2:12, Marc Zyngier wrote:

On Fri, 30 Oct 2015 14:21:50 +0800
Shannon Zhao [off-list ref] wrote:

quoted

quoted

From: Shannon Zhao <redacted>

Since the reset value of PMXEVTYPER is UNKNOWN, use reset_unknown or
reset_unknown_cp15 for its reset handler. Add access handler which
emulates writing and reading PMXEVTYPER register. When writing to
PMXEVTYPER, call kvm_pmu_set_counter_event_type to create a perf_event
for the selected event type.

Signed-off-by: Shannon Zhao <redacted>
---
 arch/arm64/kvm/sys_regs.c | 26 ++++++++++++++++++++++++--
 1 file changed, 24 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index cb82b15..4e606ea 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c

@@ -491,6 +491,17 @@ static bool access_pmu_regs(struct kvm_vcpu *vcpu,
 
 	if (p->is_write) {
 		switch (r->reg) {
+		case PMXEVTYPER_EL0: {
+			val = vcpu_sys_reg(vcpu, PMSELR_EL0);
+			kvm_pmu_set_counter_event_type(vcpu,
+						       *vcpu_reg(vcpu, p->Rt),
+						       val);

You are blindingly truncating 64bit values to u32. Is that intentional?

Yeah, the register PMXEVTYPER_EL0 and PMSELR_EL0 are all 32bit.

-- 
Shannon