[PATCH v9 03/10] arm64/kvm: expose FEAT_MTE_TAGGED_FAR feature to guest
From: Yeoreum Yun <hidden>
Date: 2025-06-18 08:45:25
Also in:
linux-doc, lkml
Subsystem:
arm64 port (aarch64 architecture), kernel virtual machine for arm64 (kvm/arm64), the rest · Maintainers:
Catalin Marinas, Will Deacon, Marc Zyngier, Oliver Upton, Linus Torvalds
expose FEAT_MTE_TAGGED_FAR feature to guest. Signed-off-by: Yeoreum Yun <redacted> --- arch/arm64/kvm/sys_regs.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-)
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 76c2f0da821f..c8c92cb9da01 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c@@ -1586,7 +1586,7 @@ static u64 __kvm_read_sanitised_id_reg(const struct kvm_vcpu *vcpu, const struct sys_reg_desc *r) { u32 id = reg_to_encoding(r); - u64 val; + u64 val, mask; if (sysreg_visible_as_raz(vcpu, r)) return 0;
@@ -1617,8 +1617,12 @@ static u64 __kvm_read_sanitised_id_reg(const struct kvm_vcpu *vcpu, val &= ~ARM64_FEATURE_MASK(ID_AA64PFR1_EL1_MPAM_frac); break; case SYS_ID_AA64PFR2_EL1: - /* We only expose FPMR */ - val &= ID_AA64PFR2_EL1_FPMR; + mask = ID_AA64PFR2_EL1_FPMR; + + if (kvm_has_mte(vcpu->kvm)) + mask |= ID_AA64PFR2_EL1_MTEFAR; + + val &= mask; break; case SYS_ID_AA64ISAR1_EL1: if (!vcpu_has_ptrauth(vcpu))
@@ -2878,7 +2882,9 @@ static const struct sys_reg_desc sys_reg_descs[] = { ID_AA64PFR1_EL1_MPAM_frac | ID_AA64PFR1_EL1_RAS_frac | ID_AA64PFR1_EL1_MTE)), - ID_WRITABLE(ID_AA64PFR2_EL1, ID_AA64PFR2_EL1_FPMR), + ID_WRITABLE(ID_AA64PFR2_EL1, + ID_AA64PFR2_EL1_FPMR | + ID_AA64PFR2_EL1_MTEFAR), ID_UNALLOCATED(4,3), ID_WRITABLE(ID_AA64ZFR0_EL1, ~ID_AA64ZFR0_EL1_RES0), ID_HIDDEN(ID_AA64SMFR0_EL1),
--
LEVI:{C3F47F37-75D8-414A-A8BA-3980EC8A46D7}