diff options
-rw-r--r-- | arch/arm64/include/asm/kvm_host.h | 2 | ||||
-rw-r--r-- | arch/arm64/kvm/debug.c | 4 | ||||
-rw-r--r-- | arch/arm64/kvm/hyp/nvhe/debug-sr.c | 32 | ||||
-rw-r--r-- | arch/arm64/kvm/hyp/nvhe/switch.c | 2 |
4 files changed, 39 insertions, 1 deletions
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 6ce2c5173482..52c2a591c447 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -704,6 +704,7 @@ struct kvm_host_data { #define KVM_HOST_DATA_FLAG_EL1_TRACING_CONFIGURED 5 #define KVM_HOST_DATA_FLAG_VCPU_IN_HYP_CONTEXT 6 #define KVM_HOST_DATA_FLAG_L1_VNCR_MAPPED 7 +#define KVM_HOST_DATA_FLAG_HAS_BRBE 8 unsigned long flags; struct kvm_cpu_context host_ctxt; @@ -737,6 +738,7 @@ struct kvm_host_data { u64 trfcr_el1; /* Values of trap registers for the host before guest entry. */ u64 mdcr_el2; + u64 brbcr_el1; } host_debug_state; /* Guest trace filter value */ diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c index 0e4c805e7e89..bc6015108a68 100644 --- a/arch/arm64/kvm/debug.c +++ b/arch/arm64/kvm/debug.c @@ -81,6 +81,10 @@ void kvm_init_host_debug_data(void) !(read_sysreg_s(SYS_PMBIDR_EL1) & PMBIDR_EL1_P)) host_data_set_flag(HAS_SPE); + /* Check if we have BRBE implemented and available at the host */ + if (cpuid_feature_extract_unsigned_field(dfr0, ID_AA64DFR0_EL1_BRBE_SHIFT)) + host_data_set_flag(HAS_BRBE); + if (cpuid_feature_extract_unsigned_field(dfr0, ID_AA64DFR0_EL1_TraceFilt_SHIFT)) { /* Force disable trace in protected mode in case of no TRBE */ if (is_protected_kvm_enabled()) diff --git a/arch/arm64/kvm/hyp/nvhe/debug-sr.c b/arch/arm64/kvm/hyp/nvhe/debug-sr.c index 2f4a4f5036bb..2a1c0f49792b 100644 --- a/arch/arm64/kvm/hyp/nvhe/debug-sr.c +++ b/arch/arm64/kvm/hyp/nvhe/debug-sr.c @@ -92,12 +92,42 @@ static void __trace_switch_to_host(void) *host_data_ptr(host_debug_state.trfcr_el1)); } +static void __debug_save_brbe(u64 *brbcr_el1) +{ + *brbcr_el1 = 0; + + /* Check if the BRBE is enabled */ + if (!(read_sysreg_el1(SYS_BRBCR) & (BRBCR_ELx_E0BRE | BRBCR_ELx_ExBRE))) + return; + + /* + * Prohibit branch record generation while we are in guest. + * Since access to BRBCR_EL1 is trapped, the guest can't + * modify the filtering set by the host. + */ + *brbcr_el1 = read_sysreg_el1(SYS_BRBCR); + write_sysreg_el1(0, SYS_BRBCR); +} + +static void __debug_restore_brbe(u64 brbcr_el1) +{ + if (!brbcr_el1) + return; + + /* Restore BRBE controls */ + write_sysreg_el1(brbcr_el1, SYS_BRBCR); +} + void __debug_save_host_buffers_nvhe(struct kvm_vcpu *vcpu) { /* Disable and flush SPE data generation */ if (host_data_test_flag(HAS_SPE)) __debug_save_spe(host_data_ptr(host_debug_state.pmscr_el1)); + /* Disable BRBE branch records */ + if (host_data_test_flag(HAS_BRBE)) + __debug_save_brbe(host_data_ptr(host_debug_state.brbcr_el1)); + if (__trace_needs_switch()) __trace_switch_to_guest(); } @@ -111,6 +141,8 @@ void __debug_restore_host_buffers_nvhe(struct kvm_vcpu *vcpu) { if (host_data_test_flag(HAS_SPE)) __debug_restore_spe(*host_data_ptr(host_debug_state.pmscr_el1)); + if (host_data_test_flag(HAS_BRBE)) + __debug_restore_brbe(*host_data_ptr(host_debug_state.brbcr_el1)); if (__trace_needs_switch()) __trace_switch_to_host(); } diff --git a/arch/arm64/kvm/hyp/nvhe/switch.c b/arch/arm64/kvm/hyp/nvhe/switch.c index 73affe1333a4..ad1da5214b5d 100644 --- a/arch/arm64/kvm/hyp/nvhe/switch.c +++ b/arch/arm64/kvm/hyp/nvhe/switch.c @@ -331,7 +331,7 @@ int __kvm_vcpu_run(struct kvm_vcpu *vcpu) * We're about to restore some new MMU state. Make sure * ongoing page-table walks that have started before we * trapped to EL2 have completed. This also synchronises the - * above disabling of SPE and TRBE. + * above disabling of BRBE, SPE and TRBE. * * See DDI0487I.a D8.1.5 "Out-of-context translation regimes", * rule R_LFHQG and subsequent information statements. |