KVM: arm64: Add POE save/restore for AT emulation fast-path

Just like the other extensions affecting address translation,
we must save/restore POE so that an out-of-context translation
context can be restored and used with the AT instructions.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Link: https://lore.kernel.org/r/20241023145345.1613824-34-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>

diff --git a/arch/arm64/kvm/at.c b/arch/arm64/kvm/at.c
index de7109111e404fd24fa7178d1bbbb5b83e9acb5e..ef1643faedeb450b4fc097d0b7fa14bf1d59b5a3 100644 (file)
--- a/arch/arm64/kvm/at.c
+++ b/arch/arm64/kvm/at.c
@@ -440,6 +440,8 @@ struct mmu_config {
        u64     tcr2;
        u64     pir;
        u64     pire0;
+       u64     por_el0;
+       u64     por_el1;
        u64     sctlr;
        u64     vttbr;
        u64     vtcr;
@@ -458,6 +460,10 @@ static void __mmu_config_save(struct mmu_config *config)
                        config->pir     = read_sysreg_el1(SYS_PIR);
                        config->pire0   = read_sysreg_el1(SYS_PIRE0);
                }
+               if (system_supports_poe()) {
+                       config->por_el1 = read_sysreg_el1(SYS_POR);
+                       config->por_el0 = read_sysreg_s(SYS_POR_EL0);
+               }
        }
        config->sctlr   = read_sysreg_el1(SYS_SCTLR);
        config->vttbr   = read_sysreg(vttbr_el2);
@@ -485,6 +491,10 @@ static void __mmu_config_restore(struct mmu_config *config)
                        write_sysreg_el1(config->pir, SYS_PIR);
                        write_sysreg_el1(config->pire0, SYS_PIRE0);
                }
+               if (system_supports_poe()) {
+                       write_sysreg_el1(config->por_el1, SYS_POR);
+                       write_sysreg_s(config->por_el0, SYS_POR_EL0);
+               }
        }
        write_sysreg_el1(config->sctlr, SYS_SCTLR);
        write_sysreg(config->vttbr,     vttbr_el2);
@@ -1105,6 +1115,10 @@ static u64 __kvm_at_s1e01_fast(struct kvm_vcpu *vcpu, u32 op, u64 vaddr)
                        write_sysreg_el1(vcpu_read_sys_reg(vcpu, PIR_EL1), SYS_PIR);
                        write_sysreg_el1(vcpu_read_sys_reg(vcpu, PIRE0_EL1), SYS_PIRE0);
                }
+               if (kvm_has_s1poe(vcpu->kvm)) {
+                       write_sysreg_el1(vcpu_read_sys_reg(vcpu, POR_EL1), SYS_POR);
+                       write_sysreg_s(vcpu_read_sys_reg(vcpu, POR_EL0), SYS_POR_EL0);
+               }
        }
        write_sysreg_el1(vcpu_read_sys_reg(vcpu, SCTLR_EL1),    SYS_SCTLR);
        __load_stage2(mmu, mmu->arch);