On 2/12/2025 9:32 AM, Binbin Wu wrote:
On 2/11/2025 6:23 PM, Xiaoyao Li wrote:
On 2/11/2025 10:54 AM, Binbin Wu wrote:
Have ____kvm_emulate_hypercall() read the GPRs instead of passing them
in via the macro.
When emulating KVM hypercalls via TDVMCALL, TDX will marshall
registers of
TDVMCALL ABI into KVM's x86 registers to match the definition of KVM
hypercall ABI _before_ ____kvm_emulate_hypercall() gets called.
Therefore,
____kvm_emulate_hypercall() can just read registers internally based
on KVM
hypercall ABI, and those registers can be removed from the
__kvm_emulate_hypercall() macro.
Also, op_64_bit can be determined inside ____kvm_emulate_hypercall(),
remove it from the __kvm_emulate_hypercall() macro as well.
After this patch, __kvm_emulate_hypercall() becomes superfluous.
we can just put the logic to call the "complete_hypercall" into
____kvm_emulate_hypercall() and rename it to __kvm_emulate_hypercall()
According to the commit message of
"KVM: x86: Refactor __kvm_emulate_hypercall() into a macro":
"Rework __kvm_emulate_hypercall() into a macro so that completion of
hypercalls that don't exit to userspace use direct function calls to the
completion helper, i.e. don't trigger a retpoline when RETPOLINE=y."
I see.
I thought the purpose of introducing the macro was for TDX usage. My
fault that didn't checking the commit message of that change.
It makes sense for retpoline reason.
So I kept the macro.
