From: Christoffer Dall <christoffer.d...@arm.com>

The VMPIDR_EL2 and VPIDR_EL2 are architecturally UNKNOWN at reset, but
let's be nice to a guest hypervisor behaving foolishly and reset these
to something reasonable anyway.

Signed-off-by: Christoffer Dall <christoffer.d...@arm.com>
Signed-off-by: Marc Zyngier <m...@kernel.org>
---
 arch/arm64/kvm/sys_regs.c | 25 +++++++++++++++++++++----
 1 file changed, 21 insertions(+), 4 deletions(-)

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index a23701f29858..730a24468915 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -618,7 +618,7 @@ static void reset_actlr(struct kvm_vcpu *vcpu, const struct 
sys_reg_desc *r)
        vcpu_write_sys_reg(vcpu, actlr, ACTLR_EL1);
 }
 
-static void reset_mpidr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
+static u64 compute_reset_mpidr(struct kvm_vcpu *vcpu)
 {
        u64 mpidr;
 
@@ -632,7 +632,24 @@ static void reset_mpidr(struct kvm_vcpu *vcpu, const 
struct sys_reg_desc *r)
        mpidr = (vcpu->vcpu_id & 0x0f) << MPIDR_LEVEL_SHIFT(0);
        mpidr |= ((vcpu->vcpu_id >> 4) & 0xff) << MPIDR_LEVEL_SHIFT(1);
        mpidr |= ((vcpu->vcpu_id >> 12) & 0xff) << MPIDR_LEVEL_SHIFT(2);
-       vcpu_write_sys_reg(vcpu, (1ULL << 31) | mpidr, MPIDR_EL1);
+       mpidr |= (1ULL << 31);
+
+       return mpidr;
+}
+
+static void reset_mpidr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
+{
+       vcpu_write_sys_reg(vcpu, compute_reset_mpidr(vcpu), MPIDR_EL1);
+}
+
+static void reset_vmpidr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
+{
+       vcpu_write_sys_reg(vcpu, compute_reset_mpidr(vcpu), VMPIDR_EL2);
+}
+
+static void reset_vpidr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
+{
+       vcpu_write_sys_reg(vcpu, read_cpuid_id(), VPIDR_EL2);
 }
 
 static unsigned int pmu_visibility(const struct kvm_vcpu *vcpu,
@@ -1882,8 +1899,8 @@ static const struct sys_reg_desc sys_reg_descs[] = {
        { PMU_SYS_REG(SYS_PMCCFILTR_EL0), .access = access_pmu_evtyper,
          .reset = reset_val, .reg = PMCCFILTR_EL0, .val = 0 },
 
-       { SYS_DESC(SYS_VPIDR_EL2), access_rw, reset_val, VPIDR_EL2, 0 },
-       { SYS_DESC(SYS_VMPIDR_EL2), access_rw, reset_val, VMPIDR_EL2, 0 },
+       { SYS_DESC(SYS_VPIDR_EL2), access_rw, reset_vpidr, VPIDR_EL2 },
+       { SYS_DESC(SYS_VMPIDR_EL2), access_rw, reset_vmpidr, VMPIDR_EL2 },
 
        { SYS_DESC(SYS_SCTLR_EL2), access_sctlr_el2, reset_val, SCTLR_EL2, 
SCTLR_EL2_RES1 },
        { SYS_DESC(SYS_ACTLR_EL2), access_rw, reset_val, ACTLR_EL2, 0 },
-- 
2.30.2

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