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[Request] ASRock X470 Taichi w/ 3.60 BIOS IOMMU groups

I’m looking to put together a VFIO-focused build using the X470 Taichi and 3700X. The Taichi is currently the top contender due to price, features and availability (and lack of X570-style chipset fan), but several discussions suggest that BIOS updates for X470 motherboards which include AGESA updates for Ryzen 3000 compatibility introduce regressions in IOMMU groups.

Can anyone with an X470 Taichi running the latest 3.60 BIOS please post the IOMMU groups. Alternatively, what X470 with the latest BIOS updates is the best option for VFIO?

I am using the X470 Failitity K4 latest bios, this might help abit

IOMMU Group 0 00:01.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe Dummy Host Bridge [1022:1452]
IOMMU Group 10 00:08.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe Dummy Host Bridge [1022:1452]
IOMMU Group 11 00:08.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Internal PCIe GPP Bridge 0 to Bus B [1022:1454]
IOMMU Group 12 00:14.0 SMBus [0c05]: Advanced Micro Devices, Inc. [AMD] FCH SMBus Controller [1022:790b] (rev 59)
IOMMU Group 12 00:14.3 ISA bridge [0601]: Advanced Micro Devices, Inc. [AMD] FCH LPC Bridge [1022:790e] (rev 51)
IOMMU Group 13 00:18.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 0 [1022:1460]
IOMMU Group 13 00:18.1 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 1 [1022:1461]
IOMMU Group 13 00:18.2 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 2 [1022:1462]
IOMMU Group 13 00:18.3 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 3 [1022:1463]
IOMMU Group 13 00:18.4 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 4 [1022:1464]
IOMMU Group 13 00:18.5 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 5 [1022:1465]
IOMMU Group 13 00:18.6 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 6 [1022:1466]
IOMMU Group 13 00:18.7 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 7 [1022:1467]
IOMMU Group 14 01:00.0 Non-Volatile memory controller [0108]: Phison Electronics Corporation Device [1987:5012] (rev 01)
IOMMU Group 15 02:00.0 USB controller [0c03]: Advanced Micro Devices, Inc. [AMD] Device [1022:43d0] (rev 01)
IOMMU Group 15 02:00.1 SATA controller [0106]: Advanced Micro Devices, Inc. [AMD] Device [1022:43c8] (rev 01)
IOMMU Group 15 02:00.2 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Device [1022:43c6] (rev 01)
IOMMU Group 15 03:00.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Device [1022:43c7] (rev 01)
IOMMU Group 15 03:01.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Device [1022:43c7] (rev 01)
IOMMU Group 15 03:02.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Device [1022:43c7] (rev 01)
IOMMU Group 15 03:03.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Device [1022:43c7] (rev 01)
IOMMU Group 15 03:04.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Device [1022:43c7] (rev 01)
IOMMU Group 15 03:06.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Device [1022:43c7] (rev 01)
IOMMU Group 15 03:07.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Device [1022:43c7] (rev 01)
IOMMU Group 15 05:00.0 Ethernet controller [0200]: Intel Corporation I211 Gigabit Network Connection [8086:1539] (rev 03)
IOMMU Group 16 0b:00.0 VGA compatible controller [0300]: NVIDIA Corporation GV104 [GeForce GTX 1180] [10de:1e87] (rev a1)
IOMMU Group 16 0b:00.1 Audio device [0403]: NVIDIA Corporation Device [10de:10f8] (rev a1)
IOMMU Group 16 0b:00.2 USB controller [0c03]: NVIDIA Corporation Device [10de:1ad8] (rev a1)
IOMMU Group 16 0b:00.3 Serial bus controller [0c80]: NVIDIA Corporation Device [10de:1ad9] (rev a1)
IOMMU Group 17 0c:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Ellesmere [Radeon RX 470/480/570/570X/580/580X] [1002:67df] (rev e7)
IOMMU Group 17 0c:00.1 Audio device [0403]: Advanced Micro Devices, Inc. [AMD/ATI] Ellesmere [Radeon RX 580] [1002:aaf0]
IOMMU Group 18 0d:00.0 Non-Essential Instrumentation [1300]: Advanced Micro Devices, Inc. [AMD] Device [1022:145a]
IOMMU Group 19 0d:00.2 Encryption controller [1080]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Platform Security Processor [1022:1456]
IOMMU Group 1 00:01.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe GPP Bridge [1022:1453]
IOMMU Group 20 0d:00.3 USB controller [0c03]: Advanced Micro Devices, Inc. [AMD] USB 3.0 Host controller [1022:145f]
IOMMU Group 21 0e:00.0 Non-Essential Instrumentation [1300]: Advanced Micro Devices, Inc. [AMD] Device [1022:1455]
IOMMU Group 22 0e:00.2 SATA controller [0106]: Advanced Micro Devices, Inc. [AMD] FCH SATA Controller [AHCI mode] [1022:7901] (rev 51)
IOMMU Group 23 0e:00.3 Audio device [0403]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) HD Audio Controller [1022:1457]
IOMMU Group 2 00:01.3 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe GPP Bridge [1022:1453]
IOMMU Group 3 00:02.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe Dummy Host Bridge [1022:1452]
IOMMU Group 4 00:03.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe Dummy Host Bridge [1022:1452]
IOMMU Group 5 00:03.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe GPP Bridge [1022:1453]
IOMMU Group 6 00:03.2 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe GPP Bridge [1022:1453]
IOMMU Group 7 00:04.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe Dummy Host Bridge [1022:1452]
IOMMU Group 8 00:07.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe Dummy Host Bridge [1022:1452]
IOMMU Group 9 00:07.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Internal PCIe GPP Bridge 0 to Bus B [1022:1454]

Thanks for posting your groups. Having USB, SATA and audio separated out (in 20, 22 and 23) could be quite handy.

I’m 90% sure the iommu groups are gonna be the same if I upgraded from 3.50 to 3.60. I got the x470 Taichi:

IOMMU Group 0:
	00:01.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-1fh) PCIe Dummy Host Bridge [1022:1452]
IOMMU Group 1:
	00:01.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe GPP Bridge [1022:1453]
IOMMU Group 10:
	00:08.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-1fh) PCIe Dummy Host Bridge [1022:1452]
IOMMU Group 11:
	00:08.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Internal PCIe GPP Bridge 0 to Bus B [1022:1454]
IOMMU Group 12:
	00:14.0 SMBus [0c05]: Advanced Micro Devices, Inc. [AMD] FCH SMBus Controller [1022:790b] (rev 59)
	00:14.3 ISA bridge [0601]: Advanced Micro Devices, Inc. [AMD] FCH LPC Bridge [1022:790e] (rev 51)
IOMMU Group 13:
	00:18.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 0 [1022:1460]
	00:18.1 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 1 [1022:1461]
	00:18.2 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 2 [1022:1462]
	00:18.3 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 3 [1022:1463]
	00:18.4 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 4 [1022:1464]
	00:18.5 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 5 [1022:1465]
	00:18.6 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 6 [1022:1466]
	00:18.7 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Data Fabric: Device 18h; Function 7 [1022:1467]
IOMMU Group 14:
	01:00.0 Non-Volatile memory controller [0108]: Sandisk Corp WD Black NVMe SSD [15b7:5001]
IOMMU Group 15:
	02:00.0 USB controller [0c03]: Advanced Micro Devices, Inc. [AMD] Device [1022:43d0] (rev 01)
	02:00.1 SATA controller [0106]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset SATA Controller [1022:43c8] (rev 01)
	02:00.2 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset PCIe Bridge [1022:43c6] (rev 01)
	03:00.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset PCIe Port [1022:43c7] (rev 01)
	03:02.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset PCIe Port [1022:43c7] (rev 01)
	03:03.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset PCIe Port [1022:43c7] (rev 01)
	03:04.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset PCIe Port [1022:43c7] (rev 01)
	03:09.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset PCIe Port [1022:43c7] (rev 01)
	04:00.0 USB controller [0c03]: ASMedia Technology Inc. ASM2142 USB 3.1 Host Controller [1b21:2142]
	05:00.0 SATA controller [0106]: ASMedia Technology Inc. ASM1062 Serial ATA Controller [1b21:0612] (rev 02)
	06:00.0 PCI bridge [0604]: ASMedia Technology Inc. ASM1184e PCIe Switch Port [1b21:1184]
	07:01.0 PCI bridge [0604]: ASMedia Technology Inc. ASM1184e PCIe Switch Port [1b21:1184]
	07:03.0 PCI bridge [0604]: ASMedia Technology Inc. ASM1184e PCIe Switch Port [1b21:1184]
	07:05.0 PCI bridge [0604]: ASMedia Technology Inc. ASM1184e PCIe Switch Port [1b21:1184]
	07:07.0 PCI bridge [0604]: ASMedia Technology Inc. ASM1184e PCIe Switch Port [1b21:1184]
	08:00.0 Network controller [0280]: Intel Corporation Dual Band Wireless-AC 3168NGW [Stone Peak] [8086:24fb] (rev 10)
	0a:00.0 Ethernet controller [0200]: Intel Corporation I211 Gigabit Network Connection [8086:1539] (rev 03)
IOMMU Group 16:
	0e:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Ellesmere [Radeon RX 470/480/570/570X/580/580X/590] [1002:67df] (rev e7)
	0e:00.1 Audio device [0403]: Advanced Micro Devices, Inc. [AMD/ATI] Ellesmere HDMI Audio [Radeon RX 470/480 / 570/580/590] [1002:aaf0]
IOMMU Group 17:
	0f:00.0 VGA compatible controller [0300]: NVIDIA Corporation GM200 [GeForce GTX 980 Ti] [10de:17c8] (rev a1)
	0f:00.1 Audio device [0403]: NVIDIA Corporation GM200 High Definition Audio [10de:0fb0] (rev a1)
IOMMU Group 18:
	10:00.0 Non-Essential Instrumentation [1300]: Advanced Micro Devices, Inc. [AMD] Zeppelin/Raven/Raven2 PCIe Dummy Function [1022:145a]
IOMMU Group 19:
	10:00.2 Encryption controller [1080]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Platform Security Processor [1022:1456]
IOMMU Group 2:
	00:01.3 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe GPP Bridge [1022:1453]
IOMMU Group 20:
	10:00.3 USB controller [0c03]: Advanced Micro Devices, Inc. [AMD] Zeppelin USB 3.0 Host controller [1022:145f]
IOMMU Group 21:
	11:00.0 Non-Essential Instrumentation [1300]: Advanced Micro Devices, Inc. [AMD] Zeppelin/Renoir PCIe Dummy Function [1022:1455]
IOMMU Group 22:
	11:00.2 SATA controller [0106]: Advanced Micro Devices, Inc. [AMD] FCH SATA Controller [AHCI mode] [1022:7901] (rev 51)
IOMMU Group 23:
	11:00.3 Audio device [0403]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) HD Audio Controller [1022:1457]
IOMMU Group 3:
	00:02.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-1fh) PCIe Dummy Host Bridge [1022:1452]
IOMMU Group 4:
	00:03.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-1fh) PCIe Dummy Host Bridge [1022:1452]
IOMMU Group 5:
	00:03.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe GPP Bridge [1022:1453]
IOMMU Group 6:
	00:03.2 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) PCIe GPP Bridge [1022:1453]
IOMMU Group 7:
	00:04.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-1fh) PCIe Dummy Host Bridge [1022:1452]
IOMMU Group 8:
	00:07.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-1fh) PCIe Dummy Host Bridge [1022:1452]
IOMMU Group 9:
	00:07.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-0fh) Internal PCIe GPP Bridge 0 to Bus B [1022:1454]

It’s been great for VFIO for me.

The X470 Taichi groups look pretty much in line with @AcidzDesigns Fatality K4 groups; probably not surprising given they’re both ASRock boards.

Since posting this thread, it’s become apparent that decent IOMMU groups aren’t the only barrier to a successful VFIO build. I’ve been following your unknown pci header type ‘127’ thread, and the current situation for both X470 and X570 seems to be less than ideal. I’m not adverse to manually patching/compiling kernels, buy would rather avoid it if at all possible.

Allegedly ASRock will be releasing BIOS updates for X470 boards in the coming weeks which contain AGESA Combo-AM4 1.0.0.4. Potentially something to keep an eye out for.

I would be adverse too if the patch didn’t work so perfectly/consistently. It’s just a few lines of code changed in the kernel. Also, you can apply the patch to an already working system and it should work fine too. If ASRock does release another BIOS and it has additional features that may benefit me, I’ll upgrade and test the patch again as I have been doing the past 3 updates since Aiber made it.

EDIT: The only reason I haven’t tested the patch with 3.60 is because ASRock explicitly recommends against upgrading to it if you are using Pinnacle Ridge (I’m on the 2700x). If someone reliable tells me it doesn’t really harm anything, I’ll test patch on 3.60 and re-post the iommu groups.

Double EDIT: Also, it’s worth mentioning that that header 127 issue affects all AMD motherboards with AGESA >=0.0.7.2

With the header 127 bug, i did create a few scripts to patch and compile the kernel for CentOS, Arch and Ubuntu. You can get them from my GitHub

Having taken the plunge to acquire an X470 Taichi, I’m now able to answer my own question. Hopefully the following is useful to someone else.

WIth BIOS 3.62 (to work around some ECC memory issues) running AGESA Combo-AM4 1.0.0.3 ABB, stock 5.3 kernel (i.e. no ACS or 127 bug workaround), IOMMU groups are as follows:

IOMMU Group 0:
	00:01.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge [1022:1482]
IOMMU Group 1:
	00:01.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse GPP Bridge [1022:1483]
IOMMU Group 2:
	00:01.3 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse GPP Bridge [1022:1483]
IOMMU Group 3:
	00:02.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge [1022:1482]
IOMMU Group 4:
	00:03.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge [1022:1482]
IOMMU Group 5:
	00:03.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse GPP Bridge [1022:1483]
IOMMU Group 6:
	00:03.2 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse GPP Bridge [1022:1483]
IOMMU Group 7:
	00:04.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge [1022:1482]
IOMMU Group 8:
	00:05.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge [1022:1482]
IOMMU Group 9:
	00:07.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge [1022:1482]
	00:07.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse Internal PCIe GPP Bridge 0 to bus[E:B] [1022:1484]
	10:00.0 Non-Essential Instrumentation [1300]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Function [1022:148a]
IOMMU Group 10:
	00:08.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge [1022:1482]
	00:08.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse Internal PCIe GPP Bridge 0 to bus[E:B] [1022:1484]
	00:08.2 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse Internal PCIe GPP Bridge 0 to bus[E:B] [1022:1484]
	00:08.3 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse Internal PCIe GPP Bridge 0 to bus[E:B] [1022:1484]
	11:00.0 Non-Essential Instrumentation [1300]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse Reserved SPP [1022:1485]
	11:00.1 Encryption controller [1080]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse Cryptographic Coprocessor PSPCPP [1022:1486]
	11:00.3 USB controller [0c03]: Advanced Micro Devices, Inc. [AMD] Matisse USB 3.0 Host Controller [1022:149c]
	11:00.4 Audio device [0403]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse HD Audio Controller [1022:1487]
	12:00.0 SATA controller [0106]: Advanced Micro Devices, Inc. [AMD] FCH SATA Controller [AHCI mode] [1022:7901] (rev 51)
	13:00.0 SATA controller [0106]: Advanced Micro Devices, Inc. [AMD] FCH SATA Controller [AHCI mode] [1022:7901] (rev 51)
IOMMU Group 11:
	00:14.0 SMBus [0c05]: Advanced Micro Devices, Inc. [AMD] FCH SMBus Controller [1022:790b] (rev 61)
	00:14.3 ISA bridge [0601]: Advanced Micro Devices, Inc. [AMD] FCH LPC Bridge [1022:790e] (rev 51)
IOMMU Group 12:
	00:18.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 0 [1022:1440]
	00:18.1 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 1 [1022:1441]
	00:18.2 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 2 [1022:1442]
	00:18.3 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 3 [1022:1443]
	00:18.4 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 4 [1022:1444]
	00:18.5 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 5 [1022:1445]
	00:18.6 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 6 [1022:1446]
	00:18.7 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 7 [1022:1447]
IOMMU Group 13:
	01:00.0 Non-Volatile memory controller [0108]: Samsung Electronics Co Ltd NVMe SSD Controller SM981/PM981/PM983 [144d:a808]
IOMMU Group 14:
	02:00.0 USB controller [0c03]: Advanced Micro Devices, Inc. [AMD] Device [1022:43d0] (rev 01)
	02:00.1 SATA controller [0106]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset SATA Controller [1022:43c8] (rev 01)
	02:00.2 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset PCIe Bridge [1022:43c6] (rev 01)
	03:00.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset PCIe Port [1022:43c7] (rev 01)
	03:02.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset PCIe Port [1022:43c7] (rev 01)
	03:03.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset PCIe Port [1022:43c7] (rev 01)
	03:04.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset PCIe Port [1022:43c7] (rev 01)
	03:09.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset PCIe Port [1022:43c7] (rev 01)
	04:00.0 USB controller [0c03]: ASMedia Technology Inc. ASM2142 USB 3.1 Host Controller [1b21:2142]
	05:00.0 SATA controller [0106]: ASMedia Technology Inc. ASM1062 Serial ATA Controller [1b21:0612] (rev 02)
	06:00.0 PCI bridge [0604]: ASMedia Technology Inc. ASM1184e PCIe Switch Port [1b21:1184]
	07:01.0 PCI bridge [0604]: ASMedia Technology Inc. ASM1184e PCIe Switch Port [1b21:1184]
	07:03.0 PCI bridge [0604]: ASMedia Technology Inc. ASM1184e PCIe Switch Port [1b21:1184]
	07:05.0 PCI bridge [0604]: ASMedia Technology Inc. ASM1184e PCIe Switch Port [1b21:1184]
	07:07.0 PCI bridge [0604]: ASMedia Technology Inc. ASM1184e PCIe Switch Port [1b21:1184]
	08:00.0 Network controller [0280]: Intel Corporation Dual Band Wireless-AC 3168NGW [Stone Peak] [8086:24fb] (rev 10)
	0a:00.0 Ethernet controller [0200]: Intel Corporation I211 Gigabit Network Connection [8086:1539] (rev 03)
IOMMU Group 15:
	0e:00.0 VGA compatible controller [0300]: NVIDIA Corporation GK208B [GeForce GT 710] [10de:128b] (rev a1)
	0e:00.1 Audio device [0403]: NVIDIA Corporation GK208 HDMI/DP Audio Controller [10de:0e0f] (rev a1)
IOMMU Group 16:
	0f:00.0 VGA compatible controller [0300]: NVIDIA Corporation TU116 [GeForce GTX 1660 Ti] [10de:2182] (rev a1)
	0f:00.1 Audio device [0403]: NVIDIA Corporation Device [10de:1aeb] (rev a1)
	0f:00.2 USB controller [0c03]: NVIDIA Corporation Device [10de:1aec] (rev a1)
	0f:00.3 Serial bus controller [0c80]: NVIDIA Corporation Device [10de:1aed] (rev a1)

As expected, without a kernel patched with the 127 bug fix I could only successfully boot a VM with passthrough once. Subsequent attempts to boot would fail until the host system was rebooted.

More recently, I’ve upgraded to the (somewhat official) 3.77 beta BIOS with AGESA Combo-AM4 1.0.0.4 Patch B. With a stock 5.3 kernel, I get the following groups

IOMMU Group 0:
	00:01.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge [1022:1482]
IOMMU Group 1:
	00:01.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse GPP Bridge [1022:1483]
IOMMU Group 2:
	00:01.3 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse GPP Bridge [1022:1483]
IOMMU Group 3:
	00:02.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge [1022:1482]
IOMMU Group 4:
	00:03.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge [1022:1482]
IOMMU Group 5:
	00:03.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse GPP Bridge [1022:1483]
IOMMU Group 6:
	00:03.2 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse GPP Bridge [1022:1483]
IOMMU Group 7:
	00:04.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge [1022:1482]
IOMMU Group 8:
	00:05.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge [1022:1482]
IOMMU Group 9:
	00:07.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge [1022:1482]
IOMMU Group 10:
	00:07.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse Internal PCIe GPP Bridge 0 to bus[E:B] [1022:1484]
IOMMU Group 11:
	00:08.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge [1022:1482]
IOMMU Group 12:
	00:08.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse Internal PCIe GPP Bridge 0 to bus[E:B] [1022:1484]
IOMMU Group 13:
	00:08.2 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse Internal PCIe GPP Bridge 0 to bus[E:B] [1022:1484]
IOMMU Group 14:
	00:08.3 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse Internal PCIe GPP Bridge 0 to bus[E:B] [1022:1484]
IOMMU Group 15:
	00:14.0 SMBus [0c05]: Advanced Micro Devices, Inc. [AMD] FCH SMBus Controller [1022:790b] (rev 61)
	00:14.3 ISA bridge [0601]: Advanced Micro Devices, Inc. [AMD] FCH LPC Bridge [1022:790e] (rev 51)
IOMMU Group 16:
	00:18.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 0 [1022:1440]
	00:18.1 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 1 [1022:1441]
	00:18.2 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 2 [1022:1442]
	00:18.3 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 3 [1022:1443]
	00:18.4 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 4 [1022:1444]
	00:18.5 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 5 [1022:1445]
	00:18.6 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 6 [1022:1446]
	00:18.7 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse Device 24: Function 7 [1022:1447]
IOMMU Group 17:
	01:00.0 Non-Volatile memory controller [0108]: Samsung Electronics Co Ltd NVMe SSD Controller SM981/PM981/PM983 [144d:a808]
IOMMU Group 18:
	02:00.0 USB controller [0c03]: Advanced Micro Devices, Inc. [AMD] Device [1022:43d0] (rev 01)
	02:00.1 SATA controller [0106]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset SATA Controller [1022:43c8] (rev 01)
	02:00.2 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset PCIe Bridge [1022:43c6] (rev 01)
	03:00.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset PCIe Port [1022:43c7] (rev 01)
	03:02.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset PCIe Port [1022:43c7] (rev 01)
	03:03.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset PCIe Port [1022:43c7] (rev 01)
	03:04.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset PCIe Port [1022:43c7] (rev 01)
	03:09.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 400 Series Chipset PCIe Port [1022:43c7] (rev 01)
	04:00.0 USB controller [0c03]: ASMedia Technology Inc. ASM2142 USB 3.1 Host Controller [1b21:2142]
	05:00.0 SATA controller [0106]: ASMedia Technology Inc. ASM1062 Serial ATA Controller [1b21:0612] (rev 02)
	06:00.0 PCI bridge [0604]: ASMedia Technology Inc. ASM1184e PCIe Switch Port [1b21:1184]
	07:01.0 PCI bridge [0604]: ASMedia Technology Inc. ASM1184e PCIe Switch Port [1b21:1184]
	07:03.0 PCI bridge [0604]: ASMedia Technology Inc. ASM1184e PCIe Switch Port [1b21:1184]
	07:05.0 PCI bridge [0604]: ASMedia Technology Inc. ASM1184e PCIe Switch Port [1b21:1184]
	07:07.0 PCI bridge [0604]: ASMedia Technology Inc. ASM1184e PCIe Switch Port [1b21:1184]
	08:00.0 Network controller [0280]: Intel Corporation Dual Band Wireless-AC 3168NGW [Stone Peak] [8086:24fb] (rev 10)
	0a:00.0 Ethernet controller [0200]: Intel Corporation I211 Gigabit Network Connection [8086:1539] (rev 03)
IOMMU Group 19:
	0e:00.0 VGA compatible controller [0300]: NVIDIA Corporation GK208B [GeForce GT 710] [10de:128b] (rev a1)
	0e:00.1 Audio device [0403]: NVIDIA Corporation GK208 HDMI/DP Audio Controller [10de:0e0f] (rev a1)
IOMMU Group 20:
	0f:00.0 VGA compatible controller [0300]: NVIDIA Corporation TU116 [GeForce GTX 1660 Ti] [10de:2182] (rev a1)
	0f:00.1 Audio device [0403]: NVIDIA Corporation Device [10de:1aeb] (rev a1)
	0f:00.2 USB controller [0c03]: NVIDIA Corporation Device [10de:1aec] (rev a1)
	0f:00.3 Serial bus controller [0c80]: NVIDIA Corporation Device [10de:1aed] (rev a1)
IOMMU Group 21:
	10:00.0 Non-Essential Instrumentation [1300]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Function [1022:148a]
IOMMU Group 22:
	11:00.0 Non-Essential Instrumentation [1300]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse Reserved SPP [1022:1485]
IOMMU Group 23:
	11:00.1 Encryption controller [1080]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse Cryptographic Coprocessor PSPCPP [1022:1486]
IOMMU Group 24:
	11:00.3 USB controller [0c03]: Advanced Micro Devices, Inc. [AMD] Matisse USB 3.0 Host Controller [1022:149c]
IOMMU Group 25:
	11:00.4 Audio device [0403]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse HD Audio Controller [1022:1487]
IOMMU Group 26:
	12:00.0 SATA controller [0106]: Advanced Micro Devices, Inc. [AMD] FCH SATA Controller [AHCI mode] [1022:7901] (rev 51)
IOMMU Group 27:
	13:00.0 SATA controller [0106]: Advanced Micro Devices, Inc. [AMD] FCH SATA Controller [AHCI mode] [1022:7901] (rev 51)

There are quite a few more groups with the latest BIOS, which I’m still playing with passing through. But, most importantly, there are no more Unknown PCI header type ‘127’ errors and the guest can be rebooted seemingly ad infinitum with no issue.

Now it’s just a matter of waiting for ASRock to formally release a non-beta BIOS with 1.0.0.4 so I can start seriously using this build.