Re: [RFC 3/3] Revert "rcutorture: Tweak kvm options"

[Dmitry Vyukov]

On Mon, Jul 1, 2019 at 4:14 PM Joel Fernandes <joel@xxxxxxxxxxxxxxxxx> wrote:
>
> On Mon, Jul 01, 2019 at 02:23:58PM +0200, Sebastian Andrzej Siewior wrote:
> > On 2019-07-01 00:04:15 [-0400], Joel Fernandes (Google) wrote:
> > > This reverts commit a6fda6dab93c2c06ef4b8cb4b9258df6674d2438 which
> > > causes kvm.sh to not run on my machines. The qemu-system-x86_64 command
> > > runs but does nothing.
> >
> > Nope. I would like to know *why* you need 'noapic' to work. Is it a
> > brand new or old qemu-system-x86_64?
>
> I did not have time to debug yesterday and I posted this particular revert as
> an 'RFC' just to make aware of this problem.
>
> I spent some more time just now, it looks like this has nothing to do with
> 'noapic' and appears to be a problem on debian distros with the e1000e NIC.
> May be this NIC was added to the virtual hardware because of -machine in the
> patch?
>
> Any if I add the following to the qemu command that kvm.sh runs, it works again:
> -net nic,model=e1000
>
> Without it I get:
>  qemu-system-x86_64: Initialization of device e1000e failed: failed to find romfile "efi-e1000e.rom"
>
> Seems to be mentioned here:
> https://bugs.launchpad.net/ubuntu/+source/ipxe/+bug/1737211
>
> And in syzkaller as well:
> https://github.com/google/syzkaller/blob/master/vm/qemu/qemu.go#L88
>
> Adding Dmitry who is syzkaller owner for any thoughts as well.

I don't have many thoughts on this. That particular error looked like
a bug in the package in the particular distro/version.


> I'm happy to write a patch to set the nic model as e1000 and send it out if
> we agree this solution is good enough.
>
>  - Joel
>