KVM: arm64: Remove hyp_panic arguments

hyp_panic is able to find all the context it needs from within itself so
remove the argument. The __hyp_panic wrapper becomes redundant so is
also removed.
Signed-off-by: Andrew Scull <ascull@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200915104643.2543892-3-ascull@google.com

arch/arm64/include/asm/kvm_hyp.h

@@ -89,7 +89,7 @@ void deactivate_traps_vhe_put(void);
 
 u64 __guest_enter(struct kvm_vcpu *vcpu, struct kvm_cpu_context *host_ctxt);
 
-void __noreturn hyp_panic(struct kvm_cpu_context *host_ctxt);
+void __noreturn hyp_panic(void);
 #ifdef __KVM_NVHE_HYPERVISOR__
 void __noreturn __hyp_do_panic(unsigned long, ...);
 #endif

arch/arm64/kvm/hyp/hyp-entry.S

@@ -210,12 +210,7 @@ SYM_FUNC_START(__hyp_do_panic)
 SYM_FUNC_END(__hyp_do_panic)
 #endif
 
-SYM_CODE_START(__hyp_panic)
-	get_host_ctxt x0, x1
-	b	hyp_panic
-SYM_CODE_END(__hyp_panic)
-
-.macro invalid_vector	label, target = __hyp_panic
+.macro invalid_vector	label, target = hyp_panic
 	.align	2
 SYM_CODE_START(\label)
 	b \target

arch/arm64/kvm/hyp/include/hyp/switch.h

@@ -510,13 +510,11 @@ static inline void __set_host_arch_workaround_state(struct kvm_vcpu *vcpu)
 static inline void __kvm_unexpected_el2_exception(void)
 {
 	unsigned long addr, fixup;
-	struct kvm_cpu_context *host_ctxt;
 	struct exception_table_entry *entry, *end;
 	unsigned long elr_el2 = read_sysreg(elr_el2);
 
 	entry = hyp_symbol_addr(__start___kvm_ex_table);
 	end = hyp_symbol_addr(__stop___kvm_ex_table);
-	host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
 
 	while (entry < end) {
 		addr = (unsigned long)&entry->insn + entry->insn;
@@ -531,7 +529,7 @@ static inline void __kvm_unexpected_el2_exception(void)
 		return;
 	}
 
-	hyp_panic(host_ctxt);
+	hyp_panic();
 }
 
 #endif /* __ARM64_KVM_HYP_SWITCH_H__ */

arch/arm64/kvm/hyp/nvhe/switch.c

@@ -242,14 +242,18 @@ int __kvm_vcpu_run(struct kvm_vcpu *vcpu)
 	return exit_code;
 }
 
-void __noreturn hyp_panic(struct kvm_cpu_context *host_ctxt)
+void __noreturn hyp_panic(void)
 {
 	u64 spsr = read_sysreg_el2(SYS_SPSR);
 	u64 elr = read_sysreg_el2(SYS_ELR);
 	u64 par = read_sysreg(par_el1);
-	struct kvm_vcpu *vcpu = host_ctxt->__hyp_running_vcpu;
+	struct kvm_cpu_context *host_ctxt;
+	struct kvm_vcpu *vcpu;
 	unsigned long str_va;
 
+	host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
+	vcpu = host_ctxt->__hyp_running_vcpu;
+
 	if (read_sysreg(vttbr_el2)) {
 		__timer_disable_traps(vcpu);
 		__deactivate_traps(vcpu);

arch/arm64/kvm/hyp/vhe/switch.c

@@ -192,10 +192,12 @@ int __kvm_vcpu_run(struct kvm_vcpu *vcpu)
 	return ret;
 }
 
-static void __hyp_call_panic(u64 spsr, u64 elr, u64 par,
-			     struct kvm_cpu_context *host_ctxt)
+static void __hyp_call_panic(u64 spsr, u64 elr, u64 par)
 {
+	struct kvm_cpu_context *host_ctxt;
 	struct kvm_vcpu *vcpu;
+
+	host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
 	vcpu = host_ctxt->__hyp_running_vcpu;
 
 	__deactivate_traps(vcpu);
@@ -208,13 +210,13 @@ static void __hyp_call_panic(u64 spsr, u64 elr, u64 par,
 }
 NOKPROBE_SYMBOL(__hyp_call_panic);
 
-void __noreturn hyp_panic(struct kvm_cpu_context *host_ctxt)
+void __noreturn hyp_panic(void)
 {
 	u64 spsr = read_sysreg_el2(SYS_SPSR);
 	u64 elr = read_sysreg_el2(SYS_ELR);
 	u64 par = read_sysreg(par_el1);
 
-	__hyp_call_panic(spsr, elr, par, host_ctxt);
+	__hyp_call_panic(spsr, elr, par);
 	unreachable();
 }