From bc37d0564c02880b336620f488540c9ab64ace41 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 6 Jan 2021 17:22:27 +0000 Subject: [PATCH] FROMGIT: KVM: arm64: Hide PMU registers from userspace when not available It appears that while we are now able to properly hide PMU registers from the guest when a PMU isn't available (either because none has been configured, the host doesn't have the PMU support compiled in, or that the HW doesn't have one at all), we are still exposing more than we should to userspace. Introduce a visibility callback gating all the PMU registers, which covers both usrespace and guest. Signed-off-by: Marc Zyngier (cherry picked from commit 11663111cd49b4c6dd27479774e420f139e4c447 git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm.git fixes) Signed-off-by: Will Deacon Change-Id: I3c2dfb7f35494bfd4141d001cb67e20be773e5b6 Bug: 178098380 Test: atest VirtualizationHostTestCases on an EL2-enabled device --- arch/arm64/kvm/sys_regs.c | 68 +++++++++++++++++++++++++++------------ 1 file changed, 48 insertions(+), 20 deletions(-) diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 33cd6e4fe48a..6886a6696b23 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -590,6 +590,15 @@ static void reset_mpidr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r) vcpu_write_sys_reg(vcpu, (1ULL << 31) | mpidr, MPIDR_EL1); } +static unsigned int pmu_visibility(const struct kvm_vcpu *vcpu, + const struct sys_reg_desc *r) +{ + if (kvm_vcpu_has_pmu(vcpu)) + return 0; + + return REG_HIDDEN; +} + static void reset_pmcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r) { u64 pmcr, val; @@ -936,15 +945,18 @@ static bool access_pmuserenr(struct kvm_vcpu *vcpu, struct sys_reg_params *p, { SYS_DESC(SYS_DBGWCRn_EL1(n)), \ trap_wcr, reset_wcr, 0, 0, get_wcr, set_wcr } +#define PMU_SYS_REG(r) \ + SYS_DESC(r), .reset = reset_unknown, .visibility = pmu_visibility + /* Macro to expand the PMEVCNTRn_EL0 register */ #define PMU_PMEVCNTR_EL0(n) \ - { SYS_DESC(SYS_PMEVCNTRn_EL0(n)), \ - access_pmu_evcntr, reset_unknown, (PMEVCNTR0_EL0 + n), } + { PMU_SYS_REG(SYS_PMEVCNTRn_EL0(n)), \ + .access = access_pmu_evcntr, .reg = (PMEVCNTR0_EL0 + n), } /* Macro to expand the PMEVTYPERn_EL0 register */ #define PMU_PMEVTYPER_EL0(n) \ - { SYS_DESC(SYS_PMEVTYPERn_EL0(n)), \ - access_pmu_evtyper, reset_unknown, (PMEVTYPER0_EL0 + n), } + { PMU_SYS_REG(SYS_PMEVTYPERn_EL0(n)), \ + .access = access_pmu_evtyper, .reg = (PMEVTYPER0_EL0 + n), } static bool undef_access(struct kvm_vcpu *vcpu, struct sys_reg_params *p, const struct sys_reg_desc *r) @@ -1495,8 +1507,10 @@ static const struct sys_reg_desc sys_reg_descs[] = { { SYS_DESC(SYS_FAR_EL1), access_vm_reg, reset_unknown, FAR_EL1 }, { SYS_DESC(SYS_PAR_EL1), NULL, reset_unknown, PAR_EL1 }, - { SYS_DESC(SYS_PMINTENSET_EL1), access_pminten, reset_unknown, PMINTENSET_EL1 }, - { SYS_DESC(SYS_PMINTENCLR_EL1), access_pminten, reset_unknown, PMINTENSET_EL1 }, + { PMU_SYS_REG(SYS_PMINTENSET_EL1), + .access = access_pminten, .reg = PMINTENSET_EL1 }, + { PMU_SYS_REG(SYS_PMINTENCLR_EL1), + .access = access_pminten, .reg = PMINTENSET_EL1 }, { SYS_DESC(SYS_MAIR_EL1), access_vm_reg, reset_unknown, MAIR_EL1 }, { SYS_DESC(SYS_AMAIR_EL1), access_vm_reg, reset_amair_el1, AMAIR_EL1 }, @@ -1535,23 +1549,36 @@ static const struct sys_reg_desc sys_reg_descs[] = { { SYS_DESC(SYS_CSSELR_EL1), access_csselr, reset_unknown, CSSELR_EL1 }, { SYS_DESC(SYS_CTR_EL0), access_ctr }, - { SYS_DESC(SYS_PMCR_EL0), access_pmcr, reset_pmcr, PMCR_EL0 }, - { SYS_DESC(SYS_PMCNTENSET_EL0), access_pmcnten, reset_unknown, PMCNTENSET_EL0 }, - { SYS_DESC(SYS_PMCNTENCLR_EL0), access_pmcnten, reset_unknown, PMCNTENSET_EL0 }, - { SYS_DESC(SYS_PMOVSCLR_EL0), access_pmovs, reset_unknown, PMOVSSET_EL0 }, - { SYS_DESC(SYS_PMSWINC_EL0), access_pmswinc, reset_unknown, PMSWINC_EL0 }, - { SYS_DESC(SYS_PMSELR_EL0), access_pmselr, reset_unknown, PMSELR_EL0 }, - { SYS_DESC(SYS_PMCEID0_EL0), access_pmceid }, - { SYS_DESC(SYS_PMCEID1_EL0), access_pmceid }, - { SYS_DESC(SYS_PMCCNTR_EL0), access_pmu_evcntr, reset_unknown, PMCCNTR_EL0 }, - { SYS_DESC(SYS_PMXEVTYPER_EL0), access_pmu_evtyper }, - { SYS_DESC(SYS_PMXEVCNTR_EL0), access_pmu_evcntr }, + { PMU_SYS_REG(SYS_PMCR_EL0), .access = access_pmcr, + .reset = reset_pmcr, .reg = PMCR_EL0 }, + { PMU_SYS_REG(SYS_PMCNTENSET_EL0), + .access = access_pmcnten, .reg = PMCNTENSET_EL0 }, + { PMU_SYS_REG(SYS_PMCNTENCLR_EL0), + .access = access_pmcnten, .reg = PMCNTENSET_EL0 }, + { PMU_SYS_REG(SYS_PMOVSCLR_EL0), + .access = access_pmovs, .reg = PMOVSSET_EL0 }, + { PMU_SYS_REG(SYS_PMSWINC_EL0), + .access = access_pmswinc, .reg = PMSWINC_EL0 }, + { PMU_SYS_REG(SYS_PMSELR_EL0), + .access = access_pmselr, .reg = PMSELR_EL0 }, + { PMU_SYS_REG(SYS_PMCEID0_EL0), + .access = access_pmceid, .reset = NULL }, + { PMU_SYS_REG(SYS_PMCEID1_EL0), + .access = access_pmceid, .reset = NULL }, + { PMU_SYS_REG(SYS_PMCCNTR_EL0), + .access = access_pmu_evcntr, .reg = PMCCNTR_EL0 }, + { PMU_SYS_REG(SYS_PMXEVTYPER_EL0), + .access = access_pmu_evtyper, .reset = NULL }, + { PMU_SYS_REG(SYS_PMXEVCNTR_EL0), + .access = access_pmu_evcntr, .reset = NULL }, /* * PMUSERENR_EL0 resets as unknown in 64bit mode while it resets as zero * in 32bit mode. Here we choose to reset it as zero for consistency. */ - { SYS_DESC(SYS_PMUSERENR_EL0), access_pmuserenr, reset_val, PMUSERENR_EL0, 0 }, - { SYS_DESC(SYS_PMOVSSET_EL0), access_pmovs, reset_unknown, PMOVSSET_EL0 }, + { PMU_SYS_REG(SYS_PMUSERENR_EL0), .access = access_pmuserenr, + .reset = reset_val, .reg = PMUSERENR_EL0, .val = 0 }, + { PMU_SYS_REG(SYS_PMOVSSET_EL0), + .access = access_pmovs, .reg = PMOVSSET_EL0 }, { SYS_DESC(SYS_TPIDR_EL0), NULL, reset_unknown, TPIDR_EL0 }, { SYS_DESC(SYS_TPIDRRO_EL0), NULL, reset_unknown, TPIDRRO_EL0 }, @@ -1703,7 +1730,8 @@ static const struct sys_reg_desc sys_reg_descs[] = { * PMCCFILTR_EL0 resets as unknown in 64bit mode while it resets as zero * in 32bit mode. Here we choose to reset it as zero for consistency. */ - { SYS_DESC(SYS_PMCCFILTR_EL0), access_pmu_evtyper, reset_val, PMCCFILTR_EL0, 0 }, + { PMU_SYS_REG(SYS_PMCCFILTR_EL0), .access = access_pmu_evtyper, + .reset = reset_val, .reg = PMCCFILTR_EL0, .val = 0 }, { SYS_DESC(SYS_DACR32_EL2), NULL, reset_unknown, DACR32_EL2 }, { SYS_DESC(SYS_IFSR32_EL2), NULL, reset_unknown, IFSR32_EL2 },