Re: [Qemu-discuss] EHCI usb passthrough not working with FreeBSD 8/9/10 guest

[Jon Doe]

On Fri, Apr 15, 2016 at 4:39 PM, Programmingkid
<address@hidden> wrote:
> On Apr 15, 2016, at 9:39 AM, Jon Doe wrote:
>
>> Fedora 21 was on qemu 2.1.3 and Fedora 23 is on 2.4.1. I'm busy trying
>> to figure out how to use mock to build a previous version of qemu for
>> Fedora 23 but it's all a bit too complex for my packaging skill level
>> :-(
>
> Top posting is kind of a no-no here.
>
> Does your system have git? If it does, then I would suggest using it to 
> download and install QEMU.
>
> git clone git://git.qemu-project.org/qemu.git
> cd qemu
> ./configure --target-list=i386-softmmu
> make
>
> If you have gcc and all of QEMU's prerequisites, then you would be able to do 
> this.
>

Ok, found the offending commit:

156a2e4dbffa85997636a7a39ef12da6f1b40254 ehci: make idt processing more robust

This security fix (CVE-2015-8558) is intended to prevent loops, but
breaks ehci in FreeBSD. Do I report this as a regression on
qemu-devel?

The 100% cpu seems to be an unrelated issue. Choosing a machine type
above pc-i440fx-2.0 ( i.e. 2.1, 2.2, etc) triggers this bug. I haven't
found the cause yet.