tdcall: return hypercall error code directly from tdvmcalls, let caller handle errors

[babayet2]

resolves #1565

[Copilot]

Pull Request Overview

This PR changes the TD call path to return raw hypercall output codes so the caller can handle errors directly.

• Changed tdcall_hypercall signature to return HypercallOutput instead of Result<(), TdVmCallR10Result>.
• Updated invoke_tdcall_hypercall in OpenHCL to propagate HypercallOutput directly.
• Adjusted imports to bring in the new HypercallOutput type.

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
vm/x86/tdcall/src/lib.rs	Switched return type of tdcall_hypercall and removed result mapping
openhcl/openhcl_boot/src/arch/x86_64/tdx.rs	Simplified invoke_tdcall_hypercall to forward HypercallOutput directly

Comments suppressed due to low confidence (3)

vm/x86/tdcall/src/lib.rs:90

• Update the doc comment for tdcall_hypercall to reflect that it now returns a HypercallOutput instead of a Result. This will make the new error-handling contract clear to callers.

) -> HypercallOutput {

vm/x86/tdcall/src/lib.rs:90

• Add unit tests for the updated tdcall_hypercall function to verify that HypercallOutput::from correctly interprets various r11 codes, per the guideline to write unit tests for new functionality.

) -> HypercallOutput {

openhcl/openhcl_boot/src/arch/x86_64/tdx.rs:158

• [nitpick] Consider adding a doc comment on invoke_tdcall_hypercall to clarify that it now directly returns the HypercallOutput and that callers must inspect the returned code for errors.

) -> hvdef::hypercall::HypercallOutput {

[benhillis]

@babayet2 - would you mind writing a bit more description about the change? Thanks!

[github-actions]

At least one Petri test failed.

[benhillis]

@babayet2 - looks like there is a tdx test failure.