From: Fuad Tabba <tabba@xxxxxxxxxx> [ Upstream commit 2fd5b4b0e7b440602455b79977bfa64dea101e6c ] Similar to VHE, calculate the value of cptr_el2 from scratch on activate traps. This removes the need to store cptr_el2 in every vcpu structure. Moreover, some traps, such as whether the guest owns the fp registers, need to be set on every vcpu run. Reported-by: James Clark <james.clark@xxxxxxxxxx> Fixes: 5294afdbf45a ("KVM: arm64: Exclude FP ownership from kvm_vcpu_arch") Signed-off-by: Fuad Tabba <tabba@xxxxxxxxxx> Link: https://lore.kernel.org/r/20241216105057.579031-13-tabba@xxxxxxxxxx Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx> Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/arm64/include/asm/kvm_host.h | 1 arch/arm64/kvm/arm.c | 1 arch/arm64/kvm/hyp/nvhe/pkvm.c | 30 ---------------------- arch/arm64/kvm/hyp/nvhe/switch.c | 51 +++++++++++++++++++++++--------------- 4 files changed, 32 insertions(+), 51 deletions(-) --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -708,7 +708,6 @@ struct kvm_vcpu_arch { u64 hcr_el2; u64 hcrx_el2; u64 mdcr_el2; - u64 cptr_el2; /* Exception Information */ struct kvm_vcpu_fault_info fault; --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1569,7 +1569,6 @@ static int kvm_arch_vcpu_ioctl_vcpu_init } vcpu_reset_hcr(vcpu); - vcpu->arch.cptr_el2 = kvm_get_reset_cptr_el2(vcpu); /* * Handle the "start in power-off" case. --- a/arch/arm64/kvm/hyp/nvhe/pkvm.c +++ b/arch/arm64/kvm/hyp/nvhe/pkvm.c @@ -31,8 +31,6 @@ static void pvm_init_traps_aa64pfr0(stru const u64 feature_ids = pvm_read_id_reg(vcpu, SYS_ID_AA64PFR0_EL1); u64 hcr_set = HCR_RW; u64 hcr_clear = 0; - u64 cptr_set = 0; - u64 cptr_clear = 0; /* Protected KVM does not support AArch32 guests. */ BUILD_BUG_ON(FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_EL0), @@ -62,21 +60,10 @@ static void pvm_init_traps_aa64pfr0(stru /* Trap AMU */ if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_AMU), feature_ids)) { hcr_clear |= HCR_AMVOFFEN; - cptr_set |= CPTR_EL2_TAM; - } - - /* Trap SVE */ - if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_SVE), feature_ids)) { - if (has_hvhe()) - cptr_clear |= CPACR_ELx_ZEN; - else - cptr_set |= CPTR_EL2_TZ; } vcpu->arch.hcr_el2 |= hcr_set; vcpu->arch.hcr_el2 &= ~hcr_clear; - vcpu->arch.cptr_el2 |= cptr_set; - vcpu->arch.cptr_el2 &= ~cptr_clear; } /* @@ -106,7 +93,6 @@ static void pvm_init_traps_aa64dfr0(stru const u64 feature_ids = pvm_read_id_reg(vcpu, SYS_ID_AA64DFR0_EL1); u64 mdcr_set = 0; u64 mdcr_clear = 0; - u64 cptr_set = 0; /* Trap/constrain PMU */ if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer), feature_ids)) { @@ -133,21 +119,12 @@ static void pvm_init_traps_aa64dfr0(stru if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_TraceFilt), feature_ids)) mdcr_set |= MDCR_EL2_TTRF; - /* Trap Trace */ - if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_TraceVer), feature_ids)) { - if (has_hvhe()) - cptr_set |= CPACR_EL1_TTA; - else - cptr_set |= CPTR_EL2_TTA; - } - /* Trap External Trace */ if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_ExtTrcBuff), feature_ids)) mdcr_clear |= MDCR_EL2_E2TB_MASK; vcpu->arch.mdcr_el2 |= mdcr_set; vcpu->arch.mdcr_el2 &= ~mdcr_clear; - vcpu->arch.cptr_el2 |= cptr_set; } /* @@ -198,10 +175,6 @@ static void pvm_init_trap_regs(struct kv /* Clear res0 and set res1 bits to trap potential new features. */ vcpu->arch.hcr_el2 &= ~(HCR_RES0); vcpu->arch.mdcr_el2 &= ~(MDCR_EL2_RES0); - if (!has_hvhe()) { - vcpu->arch.cptr_el2 |= CPTR_NVHE_EL2_RES1; - vcpu->arch.cptr_el2 &= ~(CPTR_NVHE_EL2_RES0); - } } static void pkvm_vcpu_reset_hcr(struct kvm_vcpu *vcpu) @@ -236,7 +209,6 @@ static void pkvm_vcpu_reset_hcr(struct k */ static void pkvm_vcpu_init_traps(struct kvm_vcpu *vcpu) { - vcpu->arch.cptr_el2 = kvm_get_reset_cptr_el2(vcpu); vcpu->arch.mdcr_el2 = 0; pkvm_vcpu_reset_hcr(vcpu); @@ -693,8 +665,6 @@ unlock: return ret; } - hyp_vcpu->vcpu.arch.cptr_el2 = kvm_get_reset_cptr_el2(&hyp_vcpu->vcpu); - return 0; } --- a/arch/arm64/kvm/hyp/nvhe/switch.c +++ b/arch/arm64/kvm/hyp/nvhe/switch.c @@ -36,33 +36,46 @@ DEFINE_PER_CPU(unsigned long, kvm_hyp_ve extern void kvm_nvhe_prepare_backtrace(unsigned long fp, unsigned long pc); -static void __activate_traps(struct kvm_vcpu *vcpu) +static void __activate_cptr_traps(struct kvm_vcpu *vcpu) { - u64 val; + u64 val = CPTR_EL2_TAM; /* Same bit irrespective of E2H */ - ___activate_traps(vcpu, vcpu->arch.hcr_el2); - __activate_traps_common(vcpu); + if (has_hvhe()) { + val |= CPACR_ELx_TTA; - val = vcpu->arch.cptr_el2; - val |= CPTR_EL2_TAM; /* Same bit irrespective of E2H */ - val |= has_hvhe() ? CPACR_EL1_TTA : CPTR_EL2_TTA; - if (cpus_have_final_cap(ARM64_SME)) { - if (has_hvhe()) - val &= ~CPACR_ELx_SMEN; - else - val |= CPTR_EL2_TSM; - } + if (guest_owns_fp_regs()) { + val |= CPACR_ELx_FPEN; + if (vcpu_has_sve(vcpu)) + val |= CPACR_ELx_ZEN; + } + } else { + val |= CPTR_EL2_TTA | CPTR_NVHE_EL2_RES1; + + /* + * Always trap SME since it's not supported in KVM. + * TSM is RES1 if SME isn't implemented. + */ + val |= CPTR_EL2_TSM; - if (!guest_owns_fp_regs()) { - if (has_hvhe()) - val &= ~(CPACR_ELx_FPEN | CPACR_ELx_ZEN); - else - val |= CPTR_EL2_TFP | CPTR_EL2_TZ; + if (!vcpu_has_sve(vcpu) || !guest_owns_fp_regs()) + val |= CPTR_EL2_TZ; - __activate_traps_fpsimd32(vcpu); + if (!guest_owns_fp_regs()) + val |= CPTR_EL2_TFP; } + if (!guest_owns_fp_regs()) + __activate_traps_fpsimd32(vcpu); + kvm_write_cptr_el2(val); +} + +static void __activate_traps(struct kvm_vcpu *vcpu) +{ + ___activate_traps(vcpu, vcpu->arch.hcr_el2); + __activate_traps_common(vcpu); + __activate_cptr_traps(vcpu); + write_sysreg(__this_cpu_read(kvm_hyp_vector), vbar_el2); if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) { Patches currently in stable-queue which might be from broonie@xxxxxxxxxx are queue-6.13/kvm-arm64-remove-host-fpsimd-saving-for-non-protected-kvm.patch queue-6.13/kvm-arm64-mark-some-header-functions-as-inline.patch queue-6.13/kvm-arm64-eagerly-switch-zcr_el-1-2.patch queue-6.13/kvm-arm64-unconditionally-save-flush-host-fpsimd-sve-sme-state.patch queue-6.13/kvm-arm64-refactor-exit-handlers.patch queue-6.13/kvm-arm64-remove-vhe-host-restore-of-cpacr_el1.zen.patch queue-6.13/kvm-arm64-remove-vhe-host-restore-of-cpacr_el1.smen.patch queue-6.13/kvm-arm64-calculate-cptr_el2-traps-on-activating-traps.patch