| Message ID | 1447682309-5875-1-git-send-email-mark.rutland@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, 16 Nov 2015 13:58:29 +0000 Mark Rutland <mark.rutland@arm.com> wrote: > 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. > > Signed-off-by: Mark Rutland <mark.rutland@arm.com> > Cc: Marc Zyngier <marc.zyngier@arm.com> > Cc: Christoffer Dall <christoffer.dall@linaro.org> > --- > 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 11183ce..2a8a4aa 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 |\ Acked-by: Marc Zyngier <marc.zyngier@arm.com> M.
On Mon, Nov 16, 2015 at 01:58:29PM +0000, Mark Rutland wrote: > 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. > > Signed-off-by: Mark Rutland <mark.rutland@arm.com> > Cc: Marc Zyngier <marc.zyngier@arm.com> > Cc: Christoffer Dall <christoffer.dall@linaro.org> Thanks, applied. -Christoffer
diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S index 11183ce..2a8a4aa 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 |\
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. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Christoffer Dall <christoffer.dall@linaro.org> --- arch/arm64/kvm/hyp.S | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)