From fbb4574ce9a37e15a9872860bf202f2be5bdf6c4 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Mon, 16 Nov 2015 13:58:29 +0000 Subject: [PATCH] arm64: kvm: report original PAR_EL1 upon panic If we call __kvm_hyp_panic while a guest context is active, we call __restore_sysregs before acquiring the system register values for the panic, in the process throwing away the PAR_EL1 value at the point of the panic. This patch modifies __kvm_hyp_panic to stash the PAR_EL1 value prior to restoring host register values, enabling us to report the original values at the point of the panic. Acked-by: Marc Zyngier Signed-off-by: Mark Rutland Signed-off-by: Christoffer Dall --- arch/arm64/kvm/hyp.S | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S index ce70817a9223..86c289832272 100644 --- a/arch/arm64/kvm/hyp.S +++ b/arch/arm64/kvm/hyp.S @@ -864,6 +864,10 @@ ENTRY(__kvm_flush_vm_context) ENDPROC(__kvm_flush_vm_context) __kvm_hyp_panic: + // Stash PAR_EL1 before corrupting it in __restore_sysregs + mrs x0, par_el1 + push x0, xzr + // Guess the context by looking at VTTBR: // If zero, then we're already a host. // Otherwise restore a minimal host context before panicing. @@ -898,7 +902,7 @@ __kvm_hyp_panic: mrs x3, esr_el2 mrs x4, far_el2 mrs x5, hpfar_el2 - mrs x6, par_el1 + pop x6, xzr // active context PAR_EL1 mrs x7, tpidr_el2 mov lr, #(PSR_F_BIT | PSR_I_BIT | PSR_A_BIT | PSR_D_BIT |\ -- 2.20.1