arm64: KVM: Add panic handling

Add the panic handler, together with the small bits of assembly
code to call the kernel's panic implementation.

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

diff --git a/arch/arm64/kvm/hyp/hyp-entry.S b/arch/arm64/kvm/hyp/hyp-entry.S
index 818731a5f61c7be747454065ea734316d8873a56..8e58a3ba6139a2196e2d7ae08d3919549e970b0e 100644 (file)
--- a/arch/arm64/kvm/hyp/hyp-entry.S
+++ b/arch/arm64/kvm/hyp/hyp-entry.S
@@ -155,7 +155,16 @@ el1_irq:
        mov     x1, #ARM_EXCEPTION_IRQ
        b       __guest_exit
 
-.macro invalid_vector  label, target = __kvm_hyp_panic
+ENTRY(__hyp_do_panic)
+       mov     lr, #(PSR_F_BIT | PSR_I_BIT | PSR_A_BIT | PSR_D_BIT |\
+                     PSR_MODE_EL1h)
+       msr     spsr_el2, lr
+       ldr     lr, =panic
+       msr     elr_el2, lr
+       eret
+ENDPROC(__hyp_do_panic)
+
+.macro invalid_vector  label, target = __hyp_panic
        .align  2
 \label:
        b \target

diff --git a/arch/arm64/kvm/hyp/hyp.h b/arch/arm64/kvm/hyp/hyp.h
index 70d4f696c8620fec977b10d19926798380979649..fb275178b6afecac4a22590cb94ba1e8612f7098 100644 (file)
--- a/arch/arm64/kvm/hyp/hyp.h
+++ b/arch/arm64/kvm/hyp/hyp.h
@@ -84,6 +84,7 @@ static inline bool __fpsimd_enabled(void)
 }
 
 u64 __guest_enter(struct kvm_vcpu *vcpu, struct kvm_cpu_context *host_ctxt);
+void __noreturn __hyp_do_panic(unsigned long, ...);
 
 #endif /* __ARM64_KVM_HYP_H__ */
 

diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
index 608155f5b8562d1a817aee34f34174014904de0e..b012870a92e7a81226fd80c388963b2ec9c2be8f 100644 (file)
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -141,3 +141,33 @@ int __hyp_text __guest_run(struct kvm_vcpu *vcpu)
 
        return exit_code;
 }
+
+static const char __hyp_panic_string[] = "HYP panic:\nPS:%08llx PC:%016llx ESR:%08llx\nFAR:%016llx HPFAR:%016llx PAR:%016llx\nVCPU:%p\n";
+
+void __hyp_text __noreturn __hyp_panic(void)
+{
+       unsigned long str_va = (unsigned long)__hyp_panic_string;
+       u64 spsr = read_sysreg(spsr_el2);
+       u64 elr = read_sysreg(elr_el2);
+       u64 par = read_sysreg(par_el1);
+
+       if (read_sysreg(vttbr_el2)) {
+               struct kvm_vcpu *vcpu;
+               struct kvm_cpu_context *host_ctxt;
+
+               vcpu = (struct kvm_vcpu *)read_sysreg(tpidr_el2);
+               host_ctxt = kern_hyp_va(vcpu->arch.host_cpu_context);
+               __deactivate_traps(vcpu);
+               __deactivate_vm(vcpu);
+               __sysreg_restore_state(host_ctxt);
+       }
+
+       /* Call panic for real */
+       __hyp_do_panic(hyp_kern_va(str_va),
+                      spsr,  elr,
+                      read_sysreg(esr_el2),   read_sysreg(far_el2),
+                      read_sysreg(hpfar_el2), par,
+                      (void *)read_sysreg(tpidr_el2));
+
+       unreachable();
+}