Could you please try the attached patch to see if the problem still persist.

Thanks,
Suravee

On 1/25/21 4:24 PM, Tj (Elloe Linux) wrote:
> Lenovo E495 reports:
> 
> pci 0000:00:00.2: AMD-Vi: Unable to read/write to IOMMU perf counter.
> pci 0000:00:00.2: can't derive routing for PCI INT A
> pci 0000:00:00.2: PCI INT A: not connected
> 
> I found an existing identical bug report that doesn't seem to have
> gained any attention:
> 
> https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fbugzilla.kernel.org%2Fshow_bug.cgi%3Fid%3D201753&data=04%7C01%7Csuravee.suthikulpanit%40amd.com%7C7c56640fcf24465050f008d8c145eba4%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637471853347946970%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=uykr%2FZMpr%2BuLrw3k1bKVcwywfJB4CU0p2qJSZXgLNK8%3D&reserved=0
> 
> Linux version 5.11.0-rc4+ (tj@elloe000) (gcc (Ubuntu
> 9.3.0-17ubuntu1~20.04) 9.3.0, GNU ld (GNU Binutils for Ubuntu) 2.34) #12
> SMP PREEMPT Sun Jan 24 11:28:01 GMT 2021
> Command line: BOOT_IMAGE=/vmlinuz-5.11.0-rc4+
> root=/dev/mapper/ELLOE000-rootfs ro acpi_osi=! "acpi_osi=Windows 2016"
> systemd.unified_cgroup_hierarchy=1 nosplash
> ...
> DMI: LENOVO 20NECTO1WW/20NECTO1WW, BIOS R11ET32W (1.12 ) 12/23/2019
> ...
> AMD-Vi: ivrs, add hid:PNPD0040, uid:, rdevid:152
> ...
> smpboot: CPU0: AMD Ryzen 7 3700U with Radeon Vega Mobile Gfx (family:
> 0x17, model: 0x18, stepping: 0x1)
> ...
> pci 0000:00:00.2: AMD-Vi: Unable to read/write to IOMMU perf counter.
> pci 0000:00:00.2: can't derive routing for PCI INT A
> pci 0000:00:00.2: PCI INT A: not connected
> pci 0000:00:01.0: Adding to iommu group 0
> pci 0000:00:01.1: Adding to iommu group 1
> pci 0000:00:01.2: Adding to iommu group 2
> pci 0000:00:01.3: Adding to iommu group 3
> pci 0000:00:01.6: Adding to iommu group 4
> pci 0000:00:08.0: Adding to iommu group 5
> pci 0000:00:08.1: Adding to iommu group 6
> pci 0000:00:14.0: Adding to iommu group 7
> pci 0000:00:14.3: Adding to iommu group 7
> pci 0000:00:18.0: Adding to iommu group 8
> pci 0000:00:18.1: Adding to iommu group 8
> pci 0000:00:18.2: Adding to iommu group 8
> pci 0000:00:18.3: Adding to iommu group 8
> pci 0000:00:18.4: Adding to iommu group 8
> pci 0000:00:18.5: Adding to iommu group 8
> pci 0000:00:18.6: Adding to iommu group 8
> pci 0000:00:18.7: Adding to iommu group 8
> pci 0000:01:00.0: Adding to iommu group 9
> pci 0000:02:00.0: Adding to iommu group 10
> pci 0000:03:00.0: Adding to iommu group 11
> pci 0000:04:00.0: Adding to iommu group 12
> pci 0000:05:00.0: Adding to iommu group 13
> pci 0000:05:00.1: Adding to iommu group 14
> pci 0000:05:00.2: Adding to iommu group 14
> pci 0000:05:00.3: Adding to iommu group 14
> pci 0000:05:00.4: Adding to iommu group 14
> pci 0000:05:00.5: Adding to iommu group 14
> pci 0000:05:00.6: Adding to iommu group 14
> pci 0000:00:00.2: AMD-Vi: Found IOMMU cap 0x40
> pci 0000:00:00.2: AMD-Vi: Extended features (0x4f77ef22294ada):
>   PPR NX GT IA GA PC GA_vAPIC
> AMD-Vi: Interrupt remapping enabled
> AMD-Vi: Virtual APIC enabled
> AMD-Vi: Lazy IO/TLB flushing enabled
> amd_uncore: 4  amd_df counters detected
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