Re: [Qemu-devel] vhost broken?

[Michael S. Tsirkin]

On Thu, Jan 05, 2012 at 01:16:22PM +0200, Avi Kivity wrote:
> On 01/05/2012 01:05 PM, Gerd Hoffmann wrote:
> >   Hi,
> >
> > current master seems to corrupt guest memory, I get guest errors like
> > this one:
> >
> > swap_dup: Bad swap file entry 1999800080
> > BUG: Bad page map in process udevd  pte:bec5f30054520100 pmd:1f6f4067
> > addr:00007fc464a02000 vm_flags:00100073 anon_vma:ffff88001f928ec0
> > mapping:(null) index:7fc464a02
> > Pid: 555, comm: udevd Not tainted 2.6.32-220.el6.x86_64 #1
> >
> > bisecting points to this commit:
> >
> > commit 04097f7c5957273c578f72b9bd603ba6b1d69e33
> > Author: Avi Kivity <address@hidden>
> > Date:   Sun Dec 18 14:06:05 2011 +0200
> >
> >     vhost: convert to MemoryListener API
> >
> 
> Very likely.  Michael, can you help?
> 
> I don't have a vhost setup, can you share your command line?

Just chmod /dev/vhost-net to allow access, then
add vhost=on to the tap device.
Example

-netdev
tap,id=foo,ifname=msttap0,script=/home/mst/ifup,downscript=no,vhost=on
-device virtio-net-pci,netdev=foo

> -- 
> error compiling committee.c: too many arguments to function