From 253dcbd39adb00890f3c350230ae310fcfeeb760 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 17 Nov 2015 14:07:45 +0000 Subject: [PATCH] arm64: KVM: VHE: Add alternative panic handling As the kernel fully runs in HYP when VHE is enabled, we can directly branch to the kernel's panic() implementation, and not perform an exception return. Add the alternative code to deal with this. Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier --- arch/arm64/kvm/hyp/switch.c | 35 +++++++++++++++++++++++++++-------- 1 file changed, 27 insertions(+), 8 deletions(-) diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c index e609942ef79c..731f0a2ffee0 100644 --- a/arch/arm64/kvm/hyp/switch.c +++ b/arch/arm64/kvm/hyp/switch.c @@ -210,11 +210,34 @@ __alias(__guest_run) int __kvm_vcpu_run(struct kvm_vcpu *vcpu); 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) +static void __hyp_text __hyp_call_panic_nvhe(u64 spsr, u64 elr, u64 par) { unsigned long str_va = (unsigned long)__hyp_panic_string; - u64 spsr = read_sysreg(spsr_el2); - u64 elr = read_sysreg(elr_el2); + + __hyp_do_panic(hyp_kern_va(str_va), + spsr, elr, + read_sysreg(esr_el2), read_sysreg_el2(far), + read_sysreg(hpfar_el2), par, + (void *)read_sysreg(tpidr_el2)); +} + +static void __hyp_text __hyp_call_panic_vhe(u64 spsr, u64 elr, u64 par) +{ + panic(__hyp_panic_string, + spsr, elr, + read_sysreg_el2(esr), read_sysreg_el2(far), + read_sysreg(hpfar_el2), par, + (void *)read_sysreg(tpidr_el2)); +} + +static hyp_alternate_select(__hyp_call_panic, + __hyp_call_panic_nvhe, __hyp_call_panic_vhe, + ARM64_HAS_VIRT_HOST_EXTN); + +void __hyp_text __noreturn __hyp_panic(void) +{ + u64 spsr = read_sysreg_el2(spsr); + u64 elr = read_sysreg_el2(elr); u64 par = read_sysreg(par_el1); if (read_sysreg(vttbr_el2)) { @@ -229,11 +252,7 @@ void __hyp_text __noreturn __hyp_panic(void) } /* 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)); + __hyp_call_panic()(spsr, elr, par); unreachable(); }