On Tue, Jan 25, 2022 at 11:59:02AM +0000, Marc Zyngier wrote:
Mark Brown broonie@kernel.org wrote:
- if (has_vhe()) {
if (system_supports_sme()) {
nit: if (has_vhe() && system_supports_sme()) {
saves you one level of indentation.
Yes, for now. IIRC there was some other stuff there when I had some of the code for doing the register switching properly.
/* Also restore EL0 state seen on entry */if (vcpu->arch.flags & KVM_ARM64_HOST_SME_ENABLED)sysreg_clear_set(CPACR_EL1, 0,CPACR_EL1_SMEN_EL0EN |CPACR_EL1_SMEN_EL1EN);elsesysreg_clear_set(CPACR_EL1,CPACR_EL1_SMEN_EL0EN,CPACR_EL1_SMEN_EL1EN);
I find the use of CPACR_EL1_SMEN in some cases and its individual bits in some others pretty confusing. I understand that you have modelled it after the SVE code, but maybe this is a mistake we don't need to repeat. I'd be in favour of directly exposing the individual bits in all cases.
OK, it is just the KVM code that uses the plain ZEN. I'll add a cleanup patch for that at the start of the series for ZEN I guess otherwise it looks worse, though that will inflate the size of the series a bit.