Asrock B550SL - am I screwed?

Operating Systems & Open Source Virtualization
1

I’d like to set up passthrough for a second gpu… But checking IOMMU groups brought an unpleasant surprise:

IOMMU group 2
	00:03.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge [1022:1482]
[RESET]	00:03.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse GPP Bridge [1022:1483]
[RESET]	08:00.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD/ATI] Navi 10 XL Upstream Port of PCI Express Switch [1002:1478] (rev c1)
[RESET]	09:00.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD/ATI] Navi 10 XL Downstream Port of PCI Express Switch [1002:1479]
[RESET]	0a:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Navi 23 [Radeon RX 6650 XT / 6700S / 6800S] [1002:73ef] (rev c1)
	0a:00.1 Audio device [0403]: Advanced Micro Devices, Inc. [AMD/ATI] Navi 21/23 HDMI/DP Audio Controller [1002:ab28]
IOMMU group 10
	00:18.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse/Vermeer Data Fabric: Device 18h; Function 0 [1022:1440]
	00:18.1 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse/Vermeer Data Fabric: Device 18h; Function 1 [1022:1441]
	00:18.2 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse/Vermeer Data Fabric: Device 18h; Function 2 [1022:1442]
	00:18.3 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse/Vermeer Data Fabric: Device 18h; Function 3 [1022:1443]
	00:18.4 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse/Vermeer Data Fabric: Device 18h; Function 4 [1022:1444]
	00:18.5 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse/Vermeer Data Fabric: Device 18h; Function 5 [1022:1445]
	00:18.6 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse/Vermeer Data Fabric: Device 18h; Function 6 [1022:1446]
	00:18.7 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Matisse/Vermeer Data Fabric: Device 18h; Function 7 [1022:1447]
IOMMU group 0
	00:01.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse PCIe Dummy Host Bridge [1022:1482]
[RESET]	00:01.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse GPP Bridge [1022:1483]
[RESET]	00:01.2 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Starship/Matisse GPP Bridge [1022:1483]
[RESET]	01:00.0 Non-Volatile memory controller [0108]: ADATA Technology Co., Ltd. XPG SX8200 Pro PCIe Gen3x4 M.2 2280 Solid State Drive [1cc1:8201] (rev 03)
[RESET]	02:00.0 USB controller [0c03]: Advanced Micro Devices, Inc. [AMD] 500 Series Chipset USB 3.1 XHCI Controller [1022:43ee]
	02:00.1 SATA controller [0106]: Advanced Micro Devices, Inc. [AMD] 500 Series Chipset SATA Controller [1022:43eb]
	02:00.2 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 500 Series Chipset Switch Upstream Port [1022:43e9]
[RESET]	03:00.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Device [1022:43ea]
	03:04.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Device [1022:43ea]
	03:08.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Device [1022:43ea]
	03:09.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Device [1022:43ea]
[RESET]	04:00.0 VGA compatible controller [0300]: NVIDIA Corporation GF108GL [Quadro 600] [10de:0df8] (rev a1)
	04:00.1 Audio device [0403]: NVIDIA Corporation GF108 High Definition Audio Controller [10de:0bea] (rev a1)
[RESET]	05:00.0 Non-Volatile memory controller [0108]: SK hynix Gold P31/BC711/PC711 NVMe Solid State Drive [1c5c:174a]
[RESET]	06:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8125 2.5GbE Controller [10ec:8125] (rev 05)
[RESET]	07:00.0 Network controller [0280]: Intel Corporation Wi-Fi 6 AX210/AX211/AX411 160MHz [8086:2725] (rev 1a)
IOMMU group 9
	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)

both gpus are in groups with other stuff.

Am I properly screwed or are there any options I could try?
[Asrock B550SL, bios 3.20]

2

sorry for replying so soon after posting - but I found the solution.

After changing AER Cap option to Auto in BIOS a couple more entries showed up. Among them ACS - which I enabled and now I have a whole lot more IOMMU groups :slight_smile:

It’s not all roses though - the GPU I wanted to pass is again in the bundled group. Arghhh… Any suggestions?

In the worst case scenario I’ll simply swap those gpus places… but would prefer to avoid that.

3

your second PCIe x16 Slot is only x4 and probably via Chipset, so you want your passtrough GPU in the first Slot

4

thx for suggestion, but not really. I do most of my work (and entertainment) on the Linux box (host) so I’d prefer to have the more performant GPU there.
In the Windows guest I need only “okeyish” gpu so I could use LookingGlass for simple 3d CAD work … and MS Office :smiley: . And I know the latter seems a bit funny, but I’m a “responsiveness-sensitive” kind of fella, thus spice etc quickly drives me nuts.

Sadly it seems that with this particular moba I have quite limited options - but if anyone has any ideas plz share.
At this point I’ve swapped the GPUs so my main one is in the x4 slot (ouch), while the less performant one is in the x16… Which is a bit dumb, but I don’t see the option that would allow me to have devices from x4 in separate IOMMU group so I could passthrough those.

5

with the right hardware and configuration, you wouldn’t notice any difference

6

would love to hear more about that - tried configuring spice / vnc etc and I’ve never hit the sweet spot.

Even though that wouldn’t cover the CAD part at least I could try setting up VM on my laptop for MS Office, UI Path etc.

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