On 23/06/21 04:43, Xiaoyao Li wrote:
+ else if (is_alignment_check(intr_info) &&
+ !vmx_guest_inject_ac(vcpu))
+ return true;
Why choose to check in nested_vmx_l0_wants_exit, not in
nested_vmx_l1_wants_exit()?
nested_vmx_l0_wants_exit() == true means "this is a vmexit that needs
some transformation before being injected into L1". Instead,
nested_vmx_l1_wants_exit() == true means "this is an event that should
either be processed directly by L0, or cause a vmexit in L1"
Typically, nested_vmx_l1_wants_exit() checks the controls in vmcs12,
while nested_vmx_l0_wants_exit() returns true unconditionally for most
vmexits; for others it checks processor state, or other state set up by
userspace with ioctls such as vcpu->guest_debug.
In this case it's *L0* that wants that vmexit, in order to either
disable split-lock detection or inject a SIGBUS, so
nested_vmx_l0_wants_exit() is the right one to test.
Paolo
