diff options
| author | Oliver Upton <oliver.upton@linux.dev> | 2025-09-26 12:41:07 -0700 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2025-10-13 14:17:02 +0100 |
| commit | ed25dcfbc4327570b28f0328a8e17d121434c0ea (patch) | |
| tree | dedcdd29c322a240c6718e8904580cf8abf1568a | |
| parent | 3a8660878839faadb4f1a6dd72c3179c1df56787 (diff) | |
KVM: arm64: nv: Don't treat ZCR_EL2 as a 'mapped' register
Unlike the other mapped EL2 sysregs ZCR_EL2 isn't guaranteed to be
resident when a vCPU is loaded as it actually follows the SVE
context. As such, the contents of ZCR_EL1 may belong to another guest if
the vCPU has been preempted before reaching sysreg emulation.
Unconditionally use the in-memory value of ZCR_EL2 and switch to the
memory-only accessors. The in-memory value is guaranteed to be valid as
fpsimd_lazy_switch_to_{guest,host}() will restore/save the register
appropriately.
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
| -rw-r--r-- | arch/arm64/kvm/sys_regs.c | 6 |
1 files changed, 2 insertions, 4 deletions
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 91053aa832d0..4a75e5f0c259 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -203,7 +203,6 @@ static void locate_register(const struct kvm_vcpu *vcpu, enum vcpu_sysreg reg, MAPPED_EL2_SYSREG(AMAIR_EL2, AMAIR_EL1, NULL ); MAPPED_EL2_SYSREG(ELR_EL2, ELR_EL1, NULL ); MAPPED_EL2_SYSREG(SPSR_EL2, SPSR_EL1, NULL ); - MAPPED_EL2_SYSREG(ZCR_EL2, ZCR_EL1, NULL ); MAPPED_EL2_SYSREG(CONTEXTIDR_EL2, CONTEXTIDR_EL1, NULL ); MAPPED_EL2_SYSREG(SCTLR2_EL2, SCTLR2_EL1, NULL ); case CNTHCTL_EL2: @@ -2709,14 +2708,13 @@ static bool access_zcr_el2(struct kvm_vcpu *vcpu, } if (!p->is_write) { - p->regval = vcpu_read_sys_reg(vcpu, ZCR_EL2); + p->regval = __vcpu_sys_reg(vcpu, ZCR_EL2); return true; } vq = SYS_FIELD_GET(ZCR_ELx, LEN, p->regval) + 1; vq = min(vq, vcpu_sve_max_vq(vcpu)); - vcpu_write_sys_reg(vcpu, vq - 1, ZCR_EL2); - + __vcpu_assign_sys_reg(vcpu, ZCR_EL2, vq - 1); return true; } |