@david, I cherry-picked 6778ff5b21bd8e78 and built a test kernel @ https://people.canonical.com/~alexhung/LP1917203/. I tested on an AMD Ryzen 5 2500U
Before [ 0.975812] pci 0000:00:00.2: AMD-Vi: Unable to read/write to IOMMU perf counter. After: [ 1.006639] pci 0000:00:00.2: AMD-Vi: IOMMU performance counters supported It would be great if you can give it a try and update the results. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1917203 Title: AMD-Vi: Unable to read/write to IOMMU perf counter Status in linux package in Ubuntu: In Progress Bug description: This boot warning (concealed by grub not taking over the fbcon console on a solo installation but always present on a multi-boot) has been bothering Linux users of AMD Ryzen machines for some time. The problem is currently under discussion at kernel level <https://bugzilla.kernel.org/show_bug.cgi?id=201753>. One solution proposed by Suravee Suthikulpanit <suravee.suthikulpa...@amd.com> <https://lkml.org/lkml/2021/2/8/486> works but inserts a boot-up delay of (at least) 100 msec. A second option by Alexander Monakov <amona...@ispras.ru> <https://bugzilla.kernel.org/show_bug.cgi?id=201753> also works but inserts no delay and more-or-less just moves one line of code. I've tried both solutions with kernel rebuilds for both Breezy kernel 5.8.18 and Hirsute kernel 5.10.11 and both work on my AMD Ryzen 2400G. Could I encourage your kernel experts to evaluate the situation (I think SuSE folk already are). My suggestion (as a humble user :-) ) would be to fold Alex's simple patch into your own list of kernel tweeks and get the correction out with the upcoming Hirsute release. Best regards and all respect! To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1917203/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
