@@ -183,9 +183,24 @@ void vcpu_write_sys_reg(struct kvm_vcpu *vcpu, u64 val, int reg)
goto memory_write;
if (unlikely(get_el2_mapping(reg, &el1r, &xlate))) {
+ bool need_put_load;
+
if (!is_hyp_ctxt(vcpu))
goto memory_write;
+ /*
+ * HCR_EL2.E2H is nasty: it changes the way we interpret a
+ * lot of the EL2 state, so treat is as a full state
+ * transition.
+ */
+ need_put_load = ((reg == HCR_EL2) &&
+ vcpu_el2_e2h_is_set(vcpu) != !!(val & HCR_E2H));
+
+ if (need_put_load) {
+ preempt_disable();
+ kvm_arch_vcpu_put(vcpu);
+ }
+
/*
* Always store a copy of the write to memory to avoid having
* to reverse-translate virtual EL2 system registers for a
@@ -193,6 +208,11 @@ void vcpu_write_sys_reg(struct kvm_vcpu *vcpu, u64 val, int reg)
*/
__vcpu_sys_reg(vcpu, reg) = val;
+ if (need_put_load) {
+ kvm_arch_vcpu_load(vcpu, smp_processor_id());
+ preempt_enable();
+ }
+
switch (reg) {
case ELR_EL2:
write_sysreg_el1(val, SYS_ELR);
HCR_EL2.E2H is nasty, as a flip of this bit completely changes the way we deal with a lot of the state. So when the guest flips this bit (sysregs are live), do the put/load dance so that we have a consistent state. Yes, this is slow. Don't do it. Suggested-by: Alexandru Elisei <alexandru.elisei@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> --- arch/arm64/kvm/sys_regs.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+)