On Mon, Jan 25, 2016 at 03:53:51PM +0000, Marc Zyngier wrote:
> 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.
>
> Signed-off-by: Marc Zyngier <marc.zyng...@arm.com>
Reviewed-by: Christoffer Dall <christoffer.d...@linaro.org>
> ---
> 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 77f7c94..0cadb7f 100644
> --- a/arch/arm64/kvm/hyp/switch.c
> +++ b/arch/arm64/kvm/hyp/switch.c
> @@ -211,11 +211,34 @@ __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)) {
> @@ -230,11 +253,7 @@ 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();
> }
> --
> 2.1.4
>
