On Thu, 2012-05-31 at 20:47 +0100, Richard W.M. Jones wrote: > On Thu, May 31, 2012 at 02:42:11PM -0500, Chris Adams wrote: > > Once upon a time, Adam Williamson <awilliam@xxxxxxxxxx> said: > > > On Tue, 2012-05-29 at 20:36 -0400, Jared K. Smith wrote: > > > > Yes, that's a possible culprit. I've had massive problems with VT-d > > > > enabled on both a Thinkpad T510 and on a Thinkpad X220. I don't > > > > pretend to understand what advantages VT-d is *supposed* to give me, > > > > but it's the first thing I turn off in the BIOS. In fact, on the > > > > T510, I couldn't even get an installation to complete without turning > > > > it off. > > > > > > You need it to run as a KVM host with anything resembling speed. > > > > Isn't VT-d only for VMs directly talking to the hardware, bypassing the > > host? You can run VMs with decent speed using virtualized drivers > > without VT-d (and unless you have storage controllers and network > > interfaces dedicated to each VM, virtualized drivers is the only secure > > method). > > That's right. VT-d allows the I/O port space to be partitioned like > memory, so that devices (SCSI disks etc) can be passed directly to > guests which can use them without (in theory) compromising the host, > eg. issuing DMA requests to overwrite host kernel memory. > > VT-x is what Intel calls the regular hardware virtualization > extensions. Gah. Sorry, I stopped reading after VT-. =) -- Adam Williamson Fedora QA Community Monkey IRC: adamw | Twitter: AdamW_Fedora | identi.ca: adamwfedora http://www.happyassassin.net -- devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/devel
