KVM: arm64: Don't save the host ELR_EL2 and SPSR_EL2 on VHE systems

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On non-VHE systems we need to save the ELR_EL2 and SPSR_EL2 so that we can
return to the host in EL1 in the same state and location where we issued a
hypercall to EL2, but on VHE ELR_EL2 and SPSR_EL2 are not useful because we
never enter a guest as a result of an exception entry that would be directly
handled by KVM. The kernel entry code already saves ELR_EL1/SPSR_EL1 on
exception entry, which is enough.  Therefore, factor out these registers into
separate save/restore functions, making it easy to exclude them from the VHE
world-switch path later on.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

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Christoffer Dall 2017-10-10 22:54:57 +02:00 • committed by Marc Zyngier

parent 4cdecaba01

commit 0c389d90eb

1 changed files with 13 additions and 0 deletions

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arch/arm64/kvm/hyp/sysreg-sr.c

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