Comment 20 for bug 1033727

Revision history for this message
Peter Schaefer (derschaefer) wrote : Re: [Bug 1033727] Re: USB passthrough doesn't work anymore with qemu-kvm 1.1.1

Hello Michael,

Am 1/12/2013 1:24 PM, Michael Tokarev wrote:

> Peter, are you able to run git bisect or something like that, to try to
> pinpoint either the commit which introduced this issue or which fixed
> it?

Well, i'm no expert at git, but i made some progress, see below.

> Besides, what are the sympthoms of the device non-working? Does it
> happen with linux guest too? Have you tried re-running the guest again
> when the problem occur, using the same problematic version of qemu - I
> mean, is it 100% reproducible or happens at random?

In my case it's the SmartCard-Reader that's not working, i.e. the DATEV Software called "Sicherheitspaket" does not
work. The background process called "SiPaHost.exe" just hangs; any client program trying to display SmartCard
information does also just hang forever. That behaviour is 100% reproducible and persists over reboots of the Linux host
and/or the Windows guest (Windows XP SP3). I did not try Linux guests.

Yesterday, i used git to checkout all qemu-kvm versions from kernel.org and build Debian packets from it (source kept
vanilla, i just applied the two patches that rename paths from 'qemuXXX' to 'kvmXXX').

The findings were:

- v1.0 -> ok
- v1.0.1 -> ok
- v1.1.0 -> not ok
- v1.1.1 -> not ok
- v1.1.2 -> not ok
- v1.2.0 -> not ok

So far, this is consistent with the findings in this bug report.

BUT: The latest HEAD from kernel.org (called "v1.2.50") also does work again!

So, i'm now learning about git bisect (however, today i won't have time for this).

Regards,
Peter