KVM: arm64: Prepare to handle deferred save/restore of ELR_EL1

ELR_EL1 is not used by a VHE host kernel and can be deferred, but we
need to rework the accesses to this register to access the latest value
depending on whether or not guest system registers are loaded on the CPU
or only reside in memory.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
index f32640132e26f697b9720b12a03fbac9699c7626..6ed18ce0d63833d0ba586e3a80e2e0d16804ab94 100644 (file)
--- a/arch/arm64/include/asm/kvm_emulate.h
+++ b/arch/arm64/include/asm/kvm_emulate.h
@@ -90,11 +90,27 @@ static inline unsigned long *vcpu_pc(const struct kvm_vcpu *vcpu)
        return (unsigned long *)&vcpu_gp_regs(vcpu)->regs.pc;
 }
 
-static inline unsigned long *vcpu_elr_el1(const struct kvm_vcpu *vcpu)
+static inline unsigned long *__vcpu_elr_el1(const struct kvm_vcpu *vcpu)
 {
        return (unsigned long *)&vcpu_gp_regs(vcpu)->elr_el1;
 }
 
+static inline unsigned long vcpu_read_elr_el1(const struct kvm_vcpu *vcpu)
+{
+       if (vcpu->arch.sysregs_loaded_on_cpu)
+               return read_sysreg_el1(elr);
+       else
+               return *__vcpu_elr_el1(vcpu);
+}
+
+static inline void vcpu_write_elr_el1(const struct kvm_vcpu *vcpu, unsigned long v)
+{
+       if (vcpu->arch.sysregs_loaded_on_cpu)
+               write_sysreg_el1(v, elr);
+       else
+               *__vcpu_elr_el1(vcpu) = v;
+}
+
 static inline unsigned long *vcpu_cpsr(const struct kvm_vcpu *vcpu)
 {
        return (unsigned long *)&vcpu_gp_regs(vcpu)->regs.pstate;

diff --git a/arch/arm64/kvm/inject_fault.c b/arch/arm64/kvm/inject_fault.c
index 7f8d2a4e420f71affbaa981935848b782781ded7..d8e71659ba7e1bed0d7d21c94ff0931188b8118d 100644 (file)
--- a/arch/arm64/kvm/inject_fault.c
+++ b/arch/arm64/kvm/inject_fault.c
@@ -67,7 +67,7 @@ static void inject_abt64(struct kvm_vcpu *vcpu, bool is_iabt, unsigned long addr
        bool is_aarch32 = vcpu_mode_is_32bit(vcpu);
        u32 esr = 0;
 
-       *vcpu_elr_el1(vcpu) = *vcpu_pc(vcpu);
+       vcpu_write_elr_el1(vcpu, *vcpu_pc(vcpu));
        *vcpu_pc(vcpu) = get_except_vector(vcpu, except_type_sync);
 
        *vcpu_cpsr(vcpu) = PSTATE_FAULT_BITS_64;
@@ -102,7 +102,7 @@ static void inject_undef64(struct kvm_vcpu *vcpu)
        unsigned long cpsr = *vcpu_cpsr(vcpu);
        u32 esr = (ESR_ELx_EC_UNKNOWN << ESR_ELx_EC_SHIFT);
 
-       *vcpu_elr_el1(vcpu) = *vcpu_pc(vcpu);
+       vcpu_write_elr_el1(vcpu, *vcpu_pc(vcpu));
        *vcpu_pc(vcpu) = get_except_vector(vcpu, except_type_sync);
 
        *vcpu_cpsr(vcpu) = PSTATE_FAULT_BITS_64;