On Thu, Feb 15, 2018 at 10:03:14PM +0100, Christoffer Dall wrote: > 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@xxxxxxx> > Signed-off-by: Christoffer Dall <christoffer.dall@xxxxxxxxxx> > --- > arch/arm64/kvm/hyp/sysreg-sr.c | 13 +++++++++++++ > 1 file changed, 13 insertions(+) > Reviewed-by: Andrew Jones <drjones@xxxxxxxxxx>
