<html><head><style>body{font-family:Helvetica,Arial;font-size:13px}</style></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px; color: rgba(0,0,0,1.0); margin: 0px; line-height: auto;">On November 30, 2015 at 11:31:17, Dan Ziemba (<a href="mailto:zman0900@gmail.com">zman0900@gmail.com</a>) wrote:</div> <div><blockquote type="cite" class="clean_bq" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;"><span><div><div></div><div>I recently got myself a "new" (used) gpu to replace the one I was<span class="Apple-converted-space"> </span><br>previously using for passthrough with vfio, and I discovered a strange<span class="Apple-converted-space"> </span><br>bug during this. With the new GPU being passed through to the guest,<span class="Apple-converted-space"> </span><br>the host will "sort of" crash on guest shutdown. Video output freezes<span class="Apple-converted-space"> </span><br>and all usb devices seem to stop working, but ssh access still works<span class="Apple-converted-space"> </span><br>fine. virsh cannot be accessed over ssh though, it just hangs. There<span class="Apple-converted-space"> </span><br>is a stack trace printed in dmesg, but I don't think this is the same<span class="Apple-converted-space"> </span><br>each time. See the most recent one at the bottom.<span class="Apple-converted-space"> </span><br><br>My VM is set up to use 8 1GB sized hugepages for memory. By disabling<span class="Apple-converted-space"> </span><br>hugepages completely, or switching to 4096 2MB hugepages, the crash is<span class="Apple-converted-space"> </span><br>eliminated and the guest can be shutdown or reboot as much as I want. <span class="Apple-converted-space"> </span><br>…</div></div></span></blockquote>Hi Dan,</div><div><br></div><div>Hmm interesting, I found my setup to show weird white flickery things on the guest desktop when I use 1 GB hugepages. Did you notice these things on yours? Falling back to 2 MB hugepages bring things back to normal. I didn’t experience the freezing/crashing on the hypervisor host like you describe though. How do you bind the GPU? Is it pci-stub or vfio-pci? I use vfio-pci and load it statically during boot.</div><div><br></div><div>Best regards,</div><div><font face="helvetica, arial">-- </font><br><span data-mce-style="orphans: 2; text-align: -webkit-auto; widows: 2; background-color: #ffffff; color: #020103; font-family: 'Times New Roman', serif;" style="color: rgb(2, 1, 3);"><font face="Calibri"><b>Okky Hendriansyah</b></font></span></div></body></html>