Re: xl create/save throwing errors

[Petr Beneš <w1benny@xxxxxxxxx>]

On Wed, Feb 26, 2025 at 4:46 AM Petr Beneš <w1benny@xxxxxxxxx> wrote:
>
> This is just a wild guess and it might be wrong. But clearly,
> something weird is happening around IPI during the xl save process
> that Windows doesn't like.
>

After carefully examining the crashdumps I have finally found the issue.
I looked at the stacks of the other cores and in both dumps I found
Shark.sys performing a call to KeIpiGenericCall.

Then it hit me - a long time ago I installed to the VM a tool to
defuse the PatchGuard - due to some shenanigans with a development of
an unrelated driver in the past.
I remembered that the tool installed a "Shark" driver -
https://github.com/9176324/Shark

After removing it from the VM, the "xl save" no longer causes problems.

Xen is innocent.

With that said, I'm still seeing errors during "xl create" I have
mentioned at the beginning of this mail chain, e.g.
libxl: error: libxl_aoutils.c:646:libxl__kill_xs_path: qemu
command-line probe already exited

They seem benign - they don't appear to disrupt anything. The VM is
created normally. But I have no idea why they show up.

P.