RE: [RFC RFT PATCH 0/4] Handle set_memory_XXcrypted() errors in hyperv

Michael Kelley
2024-03-07T20:25:31Z

From: Edgecombe, Rick P <rick.p.edgecombe@intel.com> Sent: Thursday, March 7, 2024 11:12 AM
>
> On Thu, 2024-03-07 at 17:11 +0000, Michael Kelley wrote:
> > Using your patches plus the changes in my comments, I've
> > done most of the testing described above. The normal
> > paths work, and when I hack set_memory_encrypted()
> > to fail, the error paths correctly did not free the memory.
> > I checked both the ring buffer memory and the additional
> > vmalloc memory allocated by the netvsc driver and the uio
> > driver.  The memory status can be checked after-the-fact
> > via /proc/vmmallocinfo and /proc/buddyinfo since these
> > are mostly large allocations. As expected, the drivers
> > output their own error messages after the failures to
> > teardown the GPADLs.
> >
> > I did not test the vmbus_disconnect() path since that
> > effectively kills the VM.
> >
> > I tested in a normal VM, and in an SEV-SNP VM.  I didn't
> > specifically test in a TDX VM, but given that Hyper-V CoCo
> > guests run with a paravisor, the guest sees the same thing
> > either way.
>
> Thanks Michael! How would you feel about reposting the patches with
> your changes added? I think you have a very good handle on the part of
> the problem I understand, and additionally much more familiarity with
> these drivers.

Yes, I can submit a new version.

Michael