Track the baseline guest value for mdcr_el2 in struct kvm_vcpu_arch. Use this value when setting mdcr_el2 for the guest. Currently this value is unchanged, but the following patches will set trapping bits based on features supported for the guest. No functional change intended. Signed-off-by: Reiji Watanabe <reijiw@xxxxxxxxxx> --- arch/arm64/include/asm/kvm_arm.h | 16 ++++++++++++++++ arch/arm64/kvm/arm.c | 1 + arch/arm64/kvm/debug.c | 13 ++++--------- 3 files changed, 21 insertions(+), 9 deletions(-) diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h index 8ab6ea038721..4b2ac9e32a36 100644 --- a/arch/arm64/include/asm/kvm_arm.h +++ b/arch/arm64/include/asm/kvm_arm.h @@ -333,6 +333,22 @@ BIT(18) | \ GENMASK(16, 15)) +/* + * The default value for the guest below also clears MDCR_EL2_E2PB_MASK + * and MDCR_EL2_E2TB_MASK to disable guest access to the profiling and + * trace buffers. + */ +#define MDCR_GUEST_FLAGS_DEFAULT \ + (MDCR_EL2_TPM | MDCR_EL2_TPMS | MDCR_EL2_TTRF | \ + MDCR_EL2_TPMCR | MDCR_EL2_TDRA | MDCR_EL2_TDOSA) + +/* Bits that are copied from vcpu->arch.mdcr_el2 to set mdcr_el2 for guest. */ +#define MDCR_GUEST_FLAGS_TRACKED_MASK \ + (MDCR_EL2_TPM | MDCR_EL2_TPMS | MDCR_EL2_TTRF | \ + MDCR_EL2_TPMCR | MDCR_EL2_TDRA | MDCR_EL2_TDOSA | \ + (MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT)) + + /* For compatibility with fault code shared with 32-bit */ #define FSC_FAULT ESR_ELx_FSC_FAULT #define FSC_ACCESS ESR_ELx_FSC_ACCESS diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 7bb744bb23ce..ce7229010a78 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1182,6 +1182,7 @@ static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, } vcpu_reset_hcr(vcpu); + vcpu->arch.mdcr_el2 = MDCR_GUEST_FLAGS_DEFAULT; if (has_vhe()) vcpu->arch.cptr_el2 = CPTR_EL2_VHE_GUEST_DEFAULT; else diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c index db9361338b2a..83330968a411 100644 --- a/arch/arm64/kvm/debug.c +++ b/arch/arm64/kvm/debug.c @@ -84,16 +84,11 @@ void kvm_arm_init_debug(void) static void kvm_arm_setup_mdcr_el2(struct kvm_vcpu *vcpu) { /* - * This also clears MDCR_EL2_E2PB_MASK and MDCR_EL2_E2TB_MASK - * to disable guest access to the profiling and trace buffers + * Keep the vcpu->arch.mdcr_el2 bits that are specified by + * MDCR_GUEST_FLAGS_TRACKED_MASK. */ - vcpu->arch.mdcr_el2 = __this_cpu_read(mdcr_el2) & MDCR_EL2_HPMN_MASK; - vcpu->arch.mdcr_el2 |= (MDCR_EL2_TPM | - MDCR_EL2_TPMS | - MDCR_EL2_TTRF | - MDCR_EL2_TPMCR | - MDCR_EL2_TDRA | - MDCR_EL2_TDOSA); + vcpu->arch.mdcr_el2 &= MDCR_GUEST_FLAGS_TRACKED_MASK; + vcpu->arch.mdcr_el2 |= __this_cpu_read(mdcr_el2) & MDCR_EL2_HPMN_MASK; /* Is the VM being debugged by userspace? */ if (vcpu->guest_debug) -- 2.35.1.723.g4982287a31-goog