KVM: arm64: pkvm: Add a generic synchronous exception injection primitive

Similarly to the "classic" KVM code, pKVM doesn't have an "anything
goes" synchronous exception injection primitive.

Carve one out of the UNDEF injection code.

Link: https://patch.msgid.link/20260108173233.2911955-8-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>

diff --git a/arch/arm64/kvm/hyp/nvhe/sys_regs.c b/arch/arm64/kvm/hyp/nvhe/sys_regs.c
index 4db0562f5bfa42e3b313a9f6b306e35e38bf53bf..b197f3eb272c1340c8a432b1d301e7d3faae2576 100644 (file)
--- a/arch/arm64/kvm/hyp/nvhe/sys_regs.c
+++ b/arch/arm64/kvm/hyp/nvhe/sys_regs.c
@@ -243,16 +243,15 @@ static u64 pvm_calc_id_reg(const struct kvm_vcpu *vcpu, u32 id)
        }
 }
 
-/*
- * Inject an unknown/undefined exception to an AArch64 guest while most of its
- * sysregs are live.
- */
-static void inject_undef64(struct kvm_vcpu *vcpu)
+static void inject_sync64(struct kvm_vcpu *vcpu, u64 esr)
 {
-       u64 esr = (ESR_ELx_EC_UNKNOWN << ESR_ELx_EC_SHIFT);
-
        *vcpu_pc(vcpu) = read_sysreg_el2(SYS_ELR);
        *vcpu_cpsr(vcpu) = read_sysreg_el2(SYS_SPSR);
+
+       /*
+        * Make sure we have the latest update to VBAR_EL1, as pKVM
+        * handles traps very early, before sysregs are resync'ed
+        */
        __vcpu_assign_sys_reg(vcpu, VBAR_EL1, read_sysreg_el1(SYS_VBAR));
 
        kvm_pend_exception(vcpu, EXCEPT_AA64_EL1_SYNC);
@@ -265,6 +264,15 @@ static void inject_undef64(struct kvm_vcpu *vcpu)
        write_sysreg_el2(*vcpu_cpsr(vcpu), SYS_SPSR);
 }
 
+/*
+ * Inject an unknown/undefined exception to an AArch64 guest while most of its
+ * sysregs are live.
+ */
+static void inject_undef64(struct kvm_vcpu *vcpu)
+{
+       inject_sync64(vcpu, (ESR_ELx_EC_UNKNOWN << ESR_ELx_EC_SHIFT));
+}
+
 static u64 read_id_reg(const struct kvm_vcpu *vcpu,
                       struct sys_reg_desc const *r)
 {