diff options
| author |   Marc Zyngier <maz@kernel.org> | 2020-03-12 16:11:24 +0000 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2020-09-29 14:19:39 +0100 |
| commit | 88865beca90621ae33217d5f23664d382f99205a (patch) | |
| tree | 7c3b9678b922c4699d985dd3dd27919da6340ba0 /arch/arm64/kvm | |
| parent | KVM: arm64: Add PMU event filtering infrastructure (diff) | |
| download | linux-dev-88865beca90621ae33217d5f23664d382f99205a.tar.xz linux-dev-88865beca90621ae33217d5f23664d382f99205a.zip | |
KVM: arm64: Mask out filtered events in PCMEID{0,1}_EL1
As we can now hide events from the guest, let's also adjust its view of
PCMEID{0,1}_EL1 so that it can figure out why some common events are not
counting as they should.
The astute user can still look into the TRM for their CPU and find out
they've been cheated, though. Nobody's perfect.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Diffstat (limited to 'arch/arm64/kvm')
| -rw-r--r-- | arch/arm64/kvm/pmu-emul.c | 29 | ||||
| -rw-r--r-- | arch/arm64/kvm/sys_regs.c | 5 |
2 files changed, 30 insertions, 4 deletions
diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c index 8cd365968af1..ee13c5eecd3d 100644 --- a/arch/arm64/kvm/pmu-emul.c +++ b/arch/arm64/kvm/pmu-emul.c @@ -763,6 +763,35 @@ static int kvm_pmu_probe_pmuver(void) return pmuver; } +u64 kvm_pmu_get_pmceid(struct kvm_vcpu *vcpu, bool pmceid1) +{ + unsigned long *bmap = vcpu->kvm->arch.pmu_filter; + u64 val, mask = 0; + int base, i; + + if (!pmceid1) { + val = read_sysreg(pmceid0_el0); + base = 0; + } else { + val = read_sysreg(pmceid1_el0); + base = 32; + } + + if (!bmap) + return val; + + for (i = 0; i < 32; i += 8) { + u64 byte; + + byte = bitmap_get_value8(bmap, base + i); + mask |= byte << i; + byte = bitmap_get_value8(bmap, 0x4000 + base + i); + mask |= byte << (32 + i); + } + + return val & mask; +} + bool kvm_arm_support_pmu_v3(void) { /* diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 077293b5115f..20ab2a7d37ca 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -769,10 +769,7 @@ static bool access_pmceid(struct kvm_vcpu *vcpu, struct sys_reg_params *p, if (pmu_access_el0_disabled(vcpu)) return false; - if (!(p->Op2 & 1)) - pmceid = read_sysreg(pmceid0_el0); - else - pmceid = read_sysreg(pmceid1_el0); + pmceid = kvm_pmu_get_pmceid(vcpu, (p->Op2 & 1)); p->regval = pmceid; |