I was attempting to rebase containerd/containerd#4419 onto #901 to verify it, and this involves upgrading hcsshim from v0.9.2 to master (+my PR).

I noticed a couple of unrelated test failures in containerd, and so I put together a branch that was just the hcsshim upgrade (specific commit in CI) and it produces the same test failures, which are different failures for the same test in Windows Server 2019 and Windows Server 2022.

The failing test is pkg/os TestResolvePath line 153, and on Windows Serve 2019 it reports:

=== FAIL: pkg/os TestResolvePath (0.50s)
    os_windows_test.go:153: failed to format VHD: failed to attach virtual disk: Incorrect function.

while on Windows Server 2022 it reports

=== FAIL: pkg/os TestResolvePath (0.22s)
    os_windows_test.go:153: failed to format VHD: failed to attach virtual disk: The process cannot access the file because it is being used by another process.

My guess is that there's some conflict between the RS5 workaround for disk handle vs VHD handle in containerd and the same workaround in hcsshim master which wasn't present in v0.9.2.

That said, since neither workaround should be active on Windows Server 2022, perhaps there's something else going on.

I haven't tested it (I might quickly do so by removing the workaround from containerd), but perhaps the function should be renamed or have its type changed in some way to highlight to callers that the API behaviour has changed and now always expects the VHD Handle, never the disk handle?