tag:blogger.com,1999:blog-8694303781453133223.post5970558615654614953..comments2023-12-12T08:07:13.883-07:00Comments on VFIO tips and tricks: VFIO GPU How To series, part 1 - The hardwareAlex Williamsonhttp://www.blogger.com/profile/02071923591707250496noreply@blogger.comBlogger5125tag:blogger.com,1999:blog-8694303781453133223.post-44435097733767499222015-08-04T05:14:49.966-06:002015-08-04T05:14:49.966-06:00Personally I use UDEV rules to attach devices auto...Personally I use UDEV rules to attach devices automatically to the desired machine. This may not solve all problems, but it seems the most convenient way to solve mine.<br />Example:<br />ACTION=="add", \<br /> SUBSYSTEM=="usb", \<br /> ENV{ID_VENDOR_ID}=="046d", \<br /> ENV{ID_MODEL_ID}=="c21f", \<br /> RUN+="/usr/bin/virsh attach-device infmc /etc/libvirt/qemu/infmc-devices/logitech-f710.xml"<br />ACTION=="remove", \<br /> SUBSYSTEM=="usb", \<br /> ENV{ID_VENDOR_ID}=="046d", \<br /> ENV{ID_MODEL_ID}=="c21f", \<br /> RUN+="/usr/bin/virsh detach-device infmc /etc/libvirt/qemu/infmc-devices/logitech-f710.xml"<br />The only issue I've met is when you shutdown machine (I have to do it before suspend host system, for example) device is detached. And you may need to replug it.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8694303781453133223.post-85271626269433177242015-05-17T14:20:43.491-06:002015-05-17T14:20:43.491-06:00It's easy to achieve, use a Xeon E5 or newer w...It's easy to achieve, use a Xeon E5 or newer with X79 or X99 chipset and you should be able to do whatever you want. If you choose to use an i5/i7 or Xeon E3 1200, then there are limitations, but often they can be worked around. See recent posts in the archlinux thread for further suggestions.Alex Williamsonhttps://www.blogger.com/profile/02071923591707250496noreply@blogger.comtag:blogger.com,1999:blog-8694303781453133223.post-12370104357286832082015-05-17T14:17:20.910-06:002015-05-17T14:17:20.910-06:00"..choose your hardware configuration approri..."..choose your hardware configuration approriately..." call me pessimistic, but maybe that's not too easy to achieve, I guess. In the best case someone else with the same goal had a piece of hardware already tested to provide proper information. I guess I will see how good this works when it comes to new/recent hardwareAnonymoushttps://www.blogger.com/profile/18117711222287795599noreply@blogger.comtag:blogger.com,1999:blog-8694303781453133223.post-20947513834536711142015-05-17T12:45:00.434-06:002015-05-17T12:45:00.434-06:00Not to be overly dramatic, but that's sort of ...Not to be overly dramatic, but that's sort of like playing Russian Roulette and saying you haven't been shot yet. You may never see a problem. You may also update QEMU some day, or install another card, or update some other software or hardware component and that lack of isolation will start to bite you. You might not even notice. Personally I'm not going to risk it, nor do I have any interest in patching my kernel forever, and if you know how IOMMU groups work and choose your hardware configuration appropriately, it's avoidable.Alex Williamsonhttps://www.blogger.com/profile/02071923591707250496noreply@blogger.comtag:blogger.com,1999:blog-8694303781453133223.post-1212950291203805392015-05-17T11:07:16.404-06:002015-05-17T11:07:16.404-06:00Thanks for the article. This is very helpful. One ...Thanks for the article. This is very helpful. One question remains: Do I only have to have a look at the isolation properties if I don't want to use the ACS patch? In other words, regardless of how the iommu groups look like without the ACS patch, by using it I can always get a proper isolation? Of course there are risks, as you wrote, but currently I already use it and I don't experiencing any downsides so far.Anonymoushttps://www.blogger.com/profile/18117711222287795599noreply@blogger.com