I've the same bug.... MOB MSI Tomahawk D450 Max and AMD Ryzen 3400G . 12/19/2020
[ 0.276768] pci 0000:00:00.2: AMD-Vi: Unable to read/write to IOMMU perf counter. [ 0.276860] pci 0000:00:00.2: can't derive routing for PCI INT A [ 0.276861] pci 0000:00:00.2: PCI INT A: not connected [ 0.276889] pci 0000:00:01.0: Adding to iommu group 0 [ 0.276900] pci 0000:00:01.2: Adding to iommu group 1 [ 0.276921] pci 0000:00:08.0: Adding to iommu group 2 [ 0.276930] pci 0000:00:08.1: Adding to iommu group 3 [ 0.276939] pci 0000:00:08.2: Adding to iommu group 4 [ 0.276952] pci 0000:00:14.0: Adding to iommu group 5 [ 0.276958] pci 0000:00:14.3: Adding to iommu group 5 [ 0.276984] pci 0000:00:18.0: Adding to iommu group 6 [ 0.276989] pci 0000:00:18.1: Adding to iommu group 6 [ 0.276995] pci 0000:00:18.2: Adding to iommu group 6 [ 0.277001] pci 0000:00:18.3: Adding to iommu group 6 [ 0.277007] pci 0000:00:18.4: Adding to iommu group 6 [ 0.277013] pci 0000:00:18.5: Adding to iommu group 6 [ 0.277019] pci 0000:00:18.6: Adding to iommu group 6 [ 0.277025] pci 0000:00:18.7: Adding to iommu group 6 [ 0.277047] pci 0000:12:00.0: Adding to iommu group 7 [ 0.277061] pci 0000:12:00.1: Adding to iommu group 7 [ 0.277075] pci 0000:12:00.2: Adding to iommu group 7 [ 0.277079] pci 0000:20:00.0: Adding to iommu group 7 [ 0.277085] pci 0000:20:01.0: Adding to iommu group 7 [ 0.277089] pci 0000:20:04.0: Adding to iommu group 7 [ 0.277093] pci 0000:20:06.0: Adding to iommu group 7 [ 0.277096] pci 0000:20:07.0: Adding to iommu group 7 [ 0.277101] pci 0000:22:00.0: Adding to iommu group 7 [ 0.277107] pci 0000:27:00.0: Adding to iommu group 7 [ 0.277135] pci 0000:29:00.0: Adding to iommu group 8 [ 0.277166] pci 0000:29:00.1: Adding to iommu group 9 [ 0.277182] pci 0000:29:00.2: Adding to iommu group 9 [ 0.277198] pci 0000:29:00.3: Adding to iommu group 9 [ 0.277215] pci 0000:29:00.4: Adding to iommu group 9 [ 0.277232] pci 0000:29:00.6: Adding to iommu group 9 [ 0.277242] pci 0000:2a:00.0: Adding to iommu group 10 [ 0.279494] pci 0000:00:00.2: AMD-Vi: Found IOMMU cap 0x40 [ 0.279495] pci 0000:00:00.2: AMD-Vi: Extended features (0x4f77ef22294ada): -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1804589 Title: AMD-Vi write error To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1804589/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs