KVM: arm64: Use BUG and BUG_ON in nVHE hyp

hyp_panic() reports the address of the panic by using ELR_EL2, but this
isn't a useful address when hyp_panic() is called directly. Replace such
direct calls with BUG() and BUG_ON() which use BRK to trigger an
exception that then goes to hyp_panic() with the correct address. Also
remove the hyp_panic() declaration from the header file to avoid
accidental misuse.

Signed-off-by: Andrew Scull <ascull@google.com>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210318143311.839894-5-ascull@google.com

diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h
index 32ae676..fe5fc81 100644 (file)
--- a/arch/arm64/include/asm/kvm_hyp.h
+++ b/arch/arm64/include/asm/kvm_hyp.h
@@ -100,7 +100,6 @@ u64 __guest_enter(struct kvm_vcpu *vcpu);
 
 bool kvm_host_psci_handler(struct kvm_cpu_context *host_ctxt);
 
-void __noreturn hyp_panic(void);
 #ifdef __KVM_NVHE_HYPERVISOR__
 void __noreturn __hyp_do_panic(struct kvm_cpu_context *host_ctxt, u64 spsr,
                               u64 elr, u64 par);

diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c
index 9363282..821a696 100644 (file)
--- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c
+++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c
@@ -178,6 +178,6 @@ void handle_trap(struct kvm_cpu_context *host_ctxt)
                handle_host_smc(host_ctxt);
                break;
        default:
-               hyp_panic();
+               BUG();
        }
 }

diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-smp.c b/arch/arm64/kvm/hyp/nvhe/hyp-smp.c
index 8795590..9f54833 100644 (file)
--- a/arch/arm64/kvm/hyp/nvhe/hyp-smp.c
+++ b/arch/arm64/kvm/hyp/nvhe/hyp-smp.c
@@ -18,8 +18,7 @@ u64 __ro_after_init hyp_cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = INVALID
 
 u64 cpu_logical_map(unsigned int cpu)
 {
-       if (cpu >= ARRAY_SIZE(hyp_cpu_logical_map))
-               hyp_panic();
+       BUG_ON(cpu >= ARRAY_SIZE(hyp_cpu_logical_map));
 
        return hyp_cpu_logical_map[cpu];
 }
@@ -30,8 +29,7 @@ unsigned long __hyp_per_cpu_offset(unsigned int cpu)
        unsigned long this_cpu_base;
        unsigned long elf_base;
 
-       if (cpu >= ARRAY_SIZE(kvm_arm_hyp_percpu_base))
-               hyp_panic();
+       BUG_ON(cpu >= ARRAY_SIZE(kvm_arm_hyp_percpu_base));
 
        cpu_base_array = (unsigned long *)&kvm_arm_hyp_percpu_base;
        this_cpu_base = kern_hyp_va(cpu_base_array[cpu]);