* Connecting multiple TB3 eGPUs via USB4 hub?
@ 2026-05-24 14:56 Dag B
2026-06-08 15:26 ` Connecting multiple TB3 eGPUs via USB4 hub?' Bjorn Helgaas
0 siblings, 1 reply; 6+ messages in thread
From: Dag B @ 2026-05-24 14:56 UTC (permalink / raw)
To: linux-pci
I am attempting to connect two TB3 enclosures to the same USB4 port via
a USB4 hub.
I cannot figure out of this is in violation of the TB3, TB4 or USB4 spec.
.... or, in case it is not:
Can this work with current USB4/Thunderbolt drivers in Linux? (I am not
worried about bandwidth limitations.)
This appears to be too niche to find answers anywhere else. I would be
very grateful for any clarifying answer here, really.
Hardware
- Framework 13 mb with 12th gen Alder Lake (Intel Corporation Alder
Lake-P Thunderbolt 4 NHI) (4 USB4 ports)
- Sonnettech Echo 5 hub (Intel Corporation Thunderbolt 4 Bridge [Goshen
Ridge 2020] )
- Razer Core X (Intel Corporation JHL6340 Thunderbolt 3 Bridge (C step)
[Alpine Ridge 2C 2016])
- GPUs are Nvidia RTX 3090. They expose two PCIe devices, the GPU and an
audio device.
Using kernel 7.0.10 with gentoo patches.
Been playing *a lot* with various permutations of pci-related kernel
options. Current options:
pci=realloc=on,hpmmiosize=256M,hpiosize=2M,hpmemsize=1G,hpbussize=0x33,pcie_scan_all,big_root_window
pcie_port_pm=off
pcie_aspm.policy=performance
thunderbolt.clx=0
Booting with 2 eGPUS directly connected to separate USB4 ports. (pcie
messages only):
[ 0.000000] Command line: root=/dev/nvme0n1p2
pci=realloc=on,hpmmiosize=256M,hpiosize=2M,hpmemsize=1G,hpbussize=0x33,pcie_scan_all,big_root_window
pcie_port_pm=off pcie_aspm.policy=performance thunderbolt.clx=0
[ 0.082296] Kernel command line:
pci=realloc=on,hpmmiosize=256M,hpiosize=2M,hpmemsize=1G,hpbussize=0x33,pcie_scan_all,big_root_window
\
[ 0.082297] Kernel command line: pcie_port_pm=off
pcie_aspm.policy=performance \
[ 0.864174] pcieport 0000:00:06.0: PME: Signaling with IRQ 122
[ 0.864343] pcieport 0000:00:07.0: PME: Signaling with IRQ 123
[ 0.864358] pcieport 0000:00:07.0: pciehp: Slot #3 AttnBtn- PwrCtrl-
MRL- AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis-
LLActRep+
[ 0.864661] pcieport 0000:00:07.1: PME: Signaling with IRQ 124
[ 0.864677] pcieport 0000:00:07.1: pciehp: Slot #4 AttnBtn- PwrCtrl-
MRL- AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis-
LLActRep+
[ 0.864900] pcieport 0000:00:07.2: PME: Signaling with IRQ 125
[ 0.864914] pcieport 0000:00:07.2: pciehp: Slot #5 AttnBtn- PwrCtrl-
MRL- AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis-
LLActRep+
[ 0.865139] pcieport 0000:00:07.3: PME: Signaling with IRQ 126
[ 0.865153] pcieport 0000:00:07.3: pciehp: Slot #6 AttnBtn- PwrCtrl-
MRL- AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis-
LLActRep+
[ 0.865376] pcieport 0000:00:1d.0: PME: Signaling with IRQ 127
[ 5.127515] pcieport 0000:00:07.3: pciehp: Slot(6): Card present
[ 5.134225] pcieport 0000:00:07.0: pciehp: Slot(3): Card present
[ 5.263158] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
can't assign; no space
[ 5.263178] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
failed to assign
[ 5.263197] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
can't assign; no space
[ 5.263215] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
failed to assign
[ 5.270527] pcieport 0000:00:07.3: PCI bridge to [bus 7d-a5]
[ 5.270529] pcieport 0000:00:07.3: bridge window [mem
0x52000000-0x5e1fffff]
[ 5.270531] pcieport 0000:00:07.3: bridge window [mem
0x6060000000-0x607bffffff 64bit pref]
[ 5.270537] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
can't assign; no space
[ 5.270537] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
failed to assign
[ 5.270538] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
can't assign; no space
[ 5.270539] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
failed to assign
[ 5.270577] pcieport 0000:00:07.3: PCI bridge to [bus 7d-a5]
[ 5.270579] pcieport 0000:00:07.3: bridge window [mem
0x52000000-0x5e1fffff]
[ 5.270581] pcieport 0000:00:07.3: bridge window [mem
0x6060000000-0x607bffffff 64bit pref]
[ 5.270703] pcieport 0000:7d:00.0: enabling device (0000 -> 0002)
[ 5.287127] pcieport 0000:7e:01.0: enabling device (0000 -> 0002)
[ 5.325065] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
can't assign; no space
[ 5.325560] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
failed to assign
[ 5.326061] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
can't assign; no space
[ 5.326560] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
failed to assign
[ 5.340678] pcieport 0000:00:07.0: PCI bridge to [bus 02-2a]
[ 5.340680] pcieport 0000:00:07.0: bridge window [mem
0x7c000000-0x881fffff]
[ 5.340682] pcieport 0000:00:07.0: bridge window [mem
0x6000000000-0x601bffffff 64bit pref]
[ 5.340688] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
can't assign; no space
[ 5.340689] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
failed to assign
[ 5.340690] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
can't assign; no space
[ 5.340690] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
failed to assign
[ 5.340741] pcieport 0000:00:07.0: PCI bridge to [bus 02-2a]
[ 5.340744] pcieport 0000:00:07.0: bridge window [mem
0x7c000000-0x881fffff]
[ 5.340745] pcieport 0000:00:07.0: bridge window [mem
0x6000000000-0x601bffffff 64bit pref]
[ 5.340866] pcieport 0000:02:00.0: enabling device (0000 -> 0002)
[ 5.355410] pcieport 0000:03:01.0: enabling device (0000 -> 0002)
Then, connecting the hub with two additional eGPUs to a third USB4 port
(all messages):
[ 596.449718] thunderbolt 0-3: new device found, vendor=0x8 device=0x5f
[ 596.449771] thunderbolt 0-3: Sonnet Technologies, Inc. Echo 5
Thunderbolt 4 Hub
[ 596.710380] thunderbolt 0-0:3.1: new retimer found, vendor=0x8087
device=0x15ee
[ 596.962295] usb 3-3: new high-speed USB device number 4 using xhci_hcd
[ 597.156102] usb 3-3: New USB device found, idVendor=1d5c,
idProduct=5801, bcdDevice= 1.01
[ 597.156118] usb 3-3: New USB device strings: Mfr=1, Product=2,
SerialNumber=0
[ 597.156130] usb 3-3: Product: USB2.0 Hub
[ 597.156138] usb 3-3: Manufacturer: Fresco Logic, Inc.
[ 597.157120] hub 3-3:1.0: USB hub found
[ 597.157152] hub 3-3:1.0: 6 ports detected
[ 597.458933] usb 2-2: new SuperSpeed Plus Gen 2x1 USB device number 4
using xhci_hcd
[ 597.472670] usb 2-2: New USB device found, idVendor=8087,
idProduct=0b40, bcdDevice=12.34
[ 597.472687] usb 2-2: New USB device strings: Mfr=1, Product=2,
SerialNumber=0
[ 597.472700] usb 2-2: Product: USB3.0 Hub
[ 597.472711] usb 2-2: Manufacturer: Intel Corporation.
[ 597.473459] hub 2-2:1.0: USB hub found
[ 597.473587] hub 2-2:1.0: 4 ports detected
[ 597.559335] thunderbolt 0-303: new device found, vendor=0x127 device=0x1
[ 597.559350] thunderbolt 0-303: Razer Core X
[ 597.702310] usb 3-3.5: new full-speed USB device number 5 using xhci_hcd
[ 597.801389] usb 3-3.5: New USB device found, idVendor=2a8c,
idProduct=205f, bcdDevice=17.46
[ 597.801406] usb 3-3.5: New USB device strings: Mfr=1, Product=2,
SerialNumber=3
[ 597.801418] usb 3-3.5: Product: Echo 5 Thunderbolt 4 Hub
[ 597.801428] usb 3-3.5: Manufacturer: Sonnet Technologies,Inc.
[ 597.801438] usb 3-3.5: SerialNumber: 11AD1D0A510D2E0D381E0B00
[ 597.885632] usb 3-3.6: new high-speed USB device number 6 using xhci_hcd
[ 597.983768] usb 3-3.6: New USB device found, idVendor=1d5c,
idProduct=5530, bcdDevice= 1.01
[ 597.983785] usb 3-3.6: New USB device strings: Mfr=1, Product=2,
SerialNumber=0
[ 597.983798] usb 3-3.6: Product: Frescologic VENDOR HID
[ 597.983807] usb 3-3.6: Manufacturer: Frescologic
[ 597.985769] hid-generic 0003:1D5C:5530.0002: hidraw1: USB HID v1.01
Device [Frescologic Frescologic VENDOR HID] on usb-0000:00:14.0-3.6/input0
[ 598.294042] thunderbolt 0-503: new device found, vendor=0x127 device=0x1
[ 598.294057] thunderbolt 0-503: Razer Core X
[ 598.619985] pcieport 0000:00:07.1: pciehp: Slot(4): Card present
[ 598.619999] pcieport 0000:00:07.1: pciehp: Slot(4): Link Up
[ 598.745860] pci 0000:2b:00.0: [8086:0b26] type 01 class 0x060400 PCIe
Switch Upstream Port
[ 598.745987] pci 0000:2b:00.0: PCI bridge to [bus 00]
[ 598.746028] pci 0000:2b:00.0: bridge window [io 0x0000-0x0fff]
[ 598.746061] pci 0000:2b:00.0: bridge window [mem
0x00000000-0x000fffff]
[ 598.746113] pci 0000:2b:00.0: bridge window [mem
0x00000000-0x000fffff 64bit pref]
[ 598.746173] pci 0000:2b:00.0: enabling Extended Tags
[ 598.746450] pci 0000:2b:00.0: supports D1 D2
[ 598.746471] pci 0000:2b:00.0: PME# supported from D0 D1 D2 D3hot D3cold
[ 598.747002] pci 0000:2b:00.0: Adding to iommu group 22
[ 598.755705] pci 0000:2b:00.0: bridge configuration invalid ([bus
00-00]), reconfiguring
[ 598.755945] pci 0000:2c:00.0: [8086:0b26] type 01 class 0x060400 PCIe
Switch Downstream Port
[ 598.756014] pci 0000:2c:00.0: PCI bridge to [bus 00]
[ 598.756039] pci 0000:2c:00.0: bridge window [io 0x0000-0x0fff]
[ 598.756059] pci 0000:2c:00.0: bridge window [mem
0x00000000-0x000fffff]
[ 598.756094] pci 0000:2c:00.0: bridge window [mem
0x00000000-0x000fffff 64bit pref]
[ 598.756136] pci 0000:2c:00.0: enabling Extended Tags
[ 598.756346] pci 0000:2c:00.0: supports D1 D2
[ 598.756359] pci 0000:2c:00.0: PME# supported from D0 D1 D2 D3hot D3cold
[ 598.756675] pci 0000:2c:00.0: Adding to iommu group 23
[ 598.756854] pci 0000:2c:01.0: [8086:0b26] type 01 class 0x060400 PCIe
Switch Downstream Port
[ 598.756925] pci 0000:2c:01.0: PCI bridge to [bus 00]
[ 598.756950] pci 0000:2c:01.0: bridge window [io 0x0000-0x0fff]
[ 598.756970] pci 0000:2c:01.0: bridge window [mem
0x00000000-0x000fffff]
[ 598.757863] pci 0000:2c:01.0: bridge window [mem
0x00000000-0x000fffff 64bit pref]
[ 598.758743] pci 0000:2c:01.0: enabling Extended Tags
[ 598.759822] pci 0000:2c:01.0: supports D1 D2
[ 598.760599] pci 0000:2c:01.0: PME# supported from D0 D1 D2 D3hot D3cold
[ 598.761582] pci 0000:2c:01.0: Adding to iommu group 24
[ 598.762477] pci 0000:2c:02.0: [8086:0b26] type 01 class 0x060400 PCIe
Switch Downstream Port
[ 598.763270] pci 0000:2c:02.0: PCI bridge to [bus 00]
[ 598.764010] pci 0000:2c:02.0: bridge window [io 0x0000-0x0fff]
[ 598.764697] pci 0000:2c:02.0: bridge window [mem
0x00000000-0x000fffff]
[ 598.765266] pci 0000:2c:02.0: bridge window [mem
0x00000000-0x000fffff 64bit pref]
[ 598.765832] pci 0000:2c:02.0: enabling Extended Tags
[ 598.766513] pci 0000:2c:02.0: supports D1 D2
[ 598.767016] pci 0000:2c:02.0: PME# supported from D0 D1 D2 D3hot D3cold
[ 598.767686] pci 0000:2c:02.0: Adding to iommu group 25
[ 598.768272] pci 0000:2c:03.0: [8086:0b26] type 01 class 0x060400 PCIe
Switch Downstream Port
[ 598.768804] pci 0000:2c:03.0: PCI bridge to [bus 00]
[ 598.769323] pci 0000:2c:03.0: bridge window [io 0x0000-0x0fff]
[ 598.769815] pci 0000:2c:03.0: bridge window [mem
0x00000000-0x000fffff]
[ 598.770317] pci 0000:2c:03.0: bridge window [mem
0x00000000-0x000fffff 64bit pref]
[ 598.770816] pci 0000:2c:03.0: enabling Extended Tags
[ 598.771451] pci 0000:2c:03.0: supports D1 D2
[ 598.771929] pci 0000:2c:03.0: PME# supported from D0 D1 D2 D3hot D3cold
[ 598.772596] pci 0000:2c:03.0: Adding to iommu group 26
[ 598.773173] pci 0000:2c:04.0: [8086:0b26] type 01 class 0x060400 PCIe
Switch Downstream Port
[ 598.773694] pci 0000:2c:04.0: PCI bridge to [bus 00]
[ 598.774196] pci 0000:2c:04.0: bridge window [io 0x0000-0x0fff]
[ 598.774683] pci 0000:2c:04.0: bridge window [mem
0x00000000-0x000fffff]
[ 598.775179] pci 0000:2c:04.0: bridge window [mem
0x00000000-0x000fffff 64bit pref]
[ 598.775687] pci 0000:2c:04.0: enabling Extended Tags
[ 598.776319] pci 0000:2c:04.0: supports D1 D2
[ 598.776794] pci 0000:2c:04.0: PME# supported from D0 D1 D2 D3hot D3cold
[ 598.777437] pci 0000:2c:04.0: Adding to iommu group 27
[ 598.777985] pci 0000:2b:00.0: PCI bridge to [bus 2c-53]
[ 598.778481] pci 0000:2c:00.0: bridge configuration invalid ([bus
00-00]), reconfiguring
[ 598.778983] pci 0000:2c:01.0: bridge configuration invalid ([bus
00-00]), reconfiguring
[ 598.779463] pci 0000:2c:02.0: bridge configuration invalid ([bus
00-00]), reconfiguring
[ 598.779939] pci 0000:2c:03.0: bridge configuration invalid ([bus
00-00]), reconfiguring
[ 598.780408] pci 0000:2c:04.0: bridge configuration invalid ([bus
00-00]), reconfiguring
[ 598.780987] pci 0000:2c:00.0: PCI bridge to [bus 2d-53]
[ 598.781458] pci_bus 0000:2d: busn_res: [bus 2d-53] end is updated to 2d
[ 598.782096] pci 0000:2e:00.0: [8086:15da] type 01 class 0x060400 PCIe
Switch Upstream Port
[ 598.782628] pci 0000:2e:00.0: PCI bridge to [bus 00]
[ 598.783089] pci 0000:2e:00.0: bridge window [io 0x0000-0x0fff]
[ 598.783548] pci 0000:2e:00.0: bridge window [mem
0x00000000-0x000fffff]
[ 598.784020] pci 0000:2e:00.0: bridge window [mem
0x00000000-0x000fffff 64bit pref]
[ 598.784493] pci 0000:2e:00.0: enabling Extended Tags
[ 598.785172] pci 0000:2e:00.0: supports D1 D2
[ 598.785624] pci 0000:2e:00.0: PME# supported from D0 D1 D2 D3hot D3cold
[ 598.786319] pci 0000:2e:00.0: Adding to iommu group 28
[ 598.792407] pci 0000:2c:01.0: PCI bridge to [bus 2e-53]
[ 598.792880] pci 0000:2e:00.0: bridge configuration invalid ([bus
00-00]), reconfiguring
[ 598.793579] pci 0000:2f:01.0: [8086:15da] type 01 class 0x060400 PCIe
Switch Downstream Port
[ 598.794094] pci 0000:2f:01.0: PCI bridge to [bus 00]
[ 598.794559] pci 0000:2f:01.0: bridge window [io 0x0000-0x0fff]
[ 598.795014] pci 0000:2f:01.0: bridge window [mem
0x00000000-0x000fffff]
[ 598.795485] pci 0000:2f:01.0: bridge window [mem
0x00000000-0x000fffff 64bit pref]
[ 598.795981] pci 0000:2f:01.0: enabling Extended Tags
[ 598.796665] pci 0000:2f:01.0: supports D1 D2
[ 598.797111] pci 0000:2f:01.0: PME# supported from D0 D1 D2 D3hot D3cold
[ 598.797785] pci 0000:2f:01.0: Adding to iommu group 29
[ 598.798344] pci 0000:2e:00.0: PCI bridge to [bus 2f-53]
[ 598.798826] pci 0000:2f:01.0: bridge configuration invalid ([bus
00-00]), reconfiguring
[ 598.799576] pci 0000:30:00.0: [10de:2204] type 00 class 0x030000 PCIe
Legacy Endpoint
[ 598.800146] pci 0000:30:00.0: BAR 0 [mem 0x00000000-0x00ffffff]
[ 598.800598] pci 0000:30:00.0: BAR 1 [mem 0x00000000-0x0fffffff 64bit
pref]
[ 598.801062] pci 0000:30:00.0: BAR 3 [mem 0x00000000-0x01ffffff 64bit
pref]
[ 598.801512] pci 0000:30:00.0: BAR 5 [io 0x0000-0x007f]
[ 598.801961] pci 0000:30:00.0: ROM [mem 0x00000000-0x0007ffff pref]
[ 598.802697] pci 0000:30:00.0: PME# supported from D0 D3hot
[ 598.803421] pci 0000:30:00.0: 8.000 Gb/s available PCIe bandwidth,
limited by 2.5 GT/s PCIe x4 link at 0000:00:07.1 (capable of 252.048
Gb/s with 16.0 GT/s PCIe x16 link)
[ 598.804053] pci 0000:30:00.0: Adding to iommu group 29
[ 598.804517] pci 0000:30:00.0: vgaarb: bridge control possible
[ 598.804969] pci 0000:30:00.0: vgaarb: VGA device added:
decodes=io+mem,owns=none,locks=none
[ 598.805427] i915 0000:00:02.0: vgaarb: VGA decodes changed:
olddecodes=none,decodes=none:owns=io+mem
[ 598.806033] pci 0000:30:00.1: [10de:1aef] type 00 class 0x040300 PCIe
Endpoint
[ 598.806622] pci 0000:30:00.1: BAR 0 [mem 0x00000000-0x00003fff]
[ 598.807434] pci 0000:30:00.1: Adding to iommu group 29
[ 598.808118] pci 0000:2f:01.0: PCI bridge to [bus 30-53]
[ 598.808614] pci_bus 0000:30: busn_res: [bus 30-53] end is updated to 30
[ 598.809107] pci_bus 0000:2f: busn_res: [bus 2f-53] end is updated to 30
[ 598.809575] pci_bus 0000:2e: busn_res: [bus 2e-53] end is updated to 53
[ 598.810077] pci_bus 0000:54: busn_res: [bus 54-7c] end is updated to 7c
[ 598.810714] pci_bus 0000:7d: busn_res: [bus 7d-a5] end is updated to a5
[ 598.811226] pci_bus 0000:a6: busn_res: [bus a6] end is updated to a6
[ 598.811682] pci_bus 0000:2c: busn_res: [bus 2c-53] end can not be
updated to a6
[ 598.812141] pci 0000:2c:00.0: disabling bridge window [mem
0x00000000-0x000fffff 64bit pref] to [bus 2d] (unused)
[ 598.812621] pci 0000:2c:00.0: disabling bridge window [mem
0x00000000-0x000fffff] to [bus 2d] (unused)
[ 598.813082] pci 0000:2c:01.0: bridge window [io 0x1000-0x1fff] to
[bus 2e-53] add_size 1ff000
[ 598.813544] pci 0000:2c:01.0: bridge window [mem
0x10000000-0x21ffffff 64bit pref] to [bus 2e-53] add_size 2e000000
add_align 10000000
[ 598.814007] pci 0000:2c:01.0: bridge window [mem
0x01000000-0x020fffff] to [bus 2e-53] add_size 3ef00000 add_align 1000000
[ 598.814474] pci 0000:2b:00.0: bridge window [io 0x1000-0x2fff] to
[bus 2c-53] add_size 1ff000
[ 598.814942] pci 0000:2b:00.0: bridge window [mem
0x10000000-0x21ffffff 64bit pref] to [bus 2c-53] add_size 2e000000
add_align 10000000
[ 598.815414] pci 0000:2b:00.0: bridge window [mem
0x01000000-0x020fffff] to [bus 2c-53] add_size 3ef00000 add_align 1000000
[ 598.815908] pcieport 0000:00:07.1: bridge window [io size 0x200000]
to [bus 2b-53] add_size 1ff000
[ 598.816393] pcieport 0000:00:07.1: bridge window [io size 0x3ff000]:
can't assign; no space
[ 598.816870] pcieport 0000:00:07.1: bridge window [io size 0x3ff000]:
failed to assign
[ 598.817346] pcieport 0000:00:07.1: bridge window [io size 0x200000]:
can't assign; no space
[ 598.817828] pcieport 0000:00:07.1: bridge window [io size 0x200000]:
failed to assign
[ 598.818304] pci 0000:2b:00.0: bridge window [mem size 0x40000000
64bit pref]: can't assign; no space
[ 598.818785] pci 0000:2b:00.0: bridge window [mem size 0x40000000
64bit pref]: failed to assign
[ 598.819281] pci 0000:2b:00.0: bridge window [mem
0x6e000000-0x7a0fffff]: assigned
[ 598.819765] pci 0000:2b:00.0: bridge window [io size 0x200000]:
can't assign; no space
[ 598.820250] pci 0000:2b:00.0: bridge window [io size 0x200000]:
failed to assign
[ 598.820740] pci 0000:2b:00.0: bridge window [mem
0x6e000000-0x7a0fffff]: releasing
[ 598.821235] pci 0000:2b:00.0: bridge window [mem
0x6020000000-0x6031ffffff 64bit pref]: assigned
[ 598.821727] pci 0000:2b:00.0: bridge window [mem
0x6e000000-0x7a0fffff]: assigned
[ 598.822227] pci 0000:2b:00.0: bridge window [io size 0x200000]:
can't assign; no space
[ 598.822722] pci 0000:2b:00.0: bridge window [io size 0x200000]:
failed to assign
[ 598.823206] pci 0000:2b:00.0: bridge window [mem
0x6020000000-0x6031ffffff 64bit pref]: failed to expand by 0x2e000000
[ 598.823697] pci 0000:2b:00.0: bridge window [mem
0x6020000000-0x6031ffffff 64bit pref]: failed to add optional 2e000000
[ 598.824186] pci 0000:2c:01.0: bridge window [mem size 0x40000000
64bit pref]: can't assign; no space
[ 598.824679] pci 0000:2c:01.0: bridge window [mem size 0x40000000
64bit pref]: failed to assign
[ 598.825173] pci 0000:2c:01.0: bridge window [mem
0x6e000000-0x720fffff]: assigned
[ 598.825677] pci 0000:2c:00.0: bridge window [io size 0x1000]: can't
assign; no space
[ 598.826173] pci 0000:2c:00.0: bridge window [io size 0x1000]: failed
to assign
[ 598.826666] pci 0000:2c:01.0: bridge window [io size 0xab000]: can't
assign; no space
[ 598.827161] pci 0000:2c:01.0: bridge window [io size 0xab000]:
failed to assign
[ 598.827652] pci 0000:2c:01.0: bridge window [mem
0x6e000000-0x720fffff]: releasing
[ 598.828140] pci 0000:2c:01.0: bridge window [mem
0x6020000000-0x6031ffffff 64bit pref]: assigned
[ 598.828630] pci 0000:2c:01.0: bridge window [mem
0x6e000000-0x720fffff]: assigned
[ 598.829132] pci 0000:2c:00.0: bridge window [io size 0x1000]: can't
assign; no space
[ 598.829623] pci 0000:2c:00.0: bridge window [io size 0x1000]: failed
to assign
[ 598.830116] pci 0000:2c:01.0: bridge window [io size 0xab000]: can't
assign; no space
[ 598.830606] pci 0000:2c:01.0: bridge window [io size 0xab000]:
failed to assign
[ 598.831099] pci 0000:2c:01.0: bridge window [mem
0x6020000000-0x6031ffffff 64bit pref]: failed to expand by 0x2e000000
[ 598.831588] pci 0000:2c:01.0: bridge window [mem
0x6020000000-0x6031ffffff 64bit pref]: failed to add optional 2e000000
[ 598.832080] pci 0000:2c:00.0: PCI bridge to [bus 2d]
[ 598.832605] pci 0000:2e:00.0: bridge window [mem
0x6020000000-0x6031ffffff 64bit pref]: assigned
[ 598.833106] pci 0000:2e:00.0: bridge window [mem
0x6e000000-0x720fffff]: assigned
[ 598.833599] pci 0000:2e:00.0: bridge window [io size 0xab000]: can't
assign; no space
[ 598.834091] pci 0000:2e:00.0: bridge window [io size 0xab000]:
failed to assign
[ 598.834590] pci 0000:2e:00.0: bridge window [io size 0xab000]: can't
assign; no space
[ 598.835088] pci 0000:2e:00.0: bridge window [io size 0xab000]:
failed to assign
[ 598.835592] pci 0000:2f:01.0: bridge window [mem
0x6020000000-0x6031ffffff 64bit pref]: assigned
[ 598.836098] pci 0000:2f:01.0: bridge window [mem
0x6e000000-0x720fffff]: assigned
[ 598.836600] pci 0000:2f:01.0: bridge window [io size 0xab000]: can't
assign; no space
[ 598.837097] pci 0000:2f:01.0: bridge window [io size 0xab000]:
failed to assign
[ 598.837585] pci 0000:2f:01.0: bridge window [io size 0xab000]: can't
assign; no space
[ 598.838073] pci 0000:2f:01.0: bridge window [io size 0xab000]:
failed to assign
[ 598.838559] pci 0000:30:00.0: BAR 1 [mem 0x6020000000-0x602fffffff
64bit pref]: assigned
[ 598.839079] pci 0000:30:00.0: BAR 3 [mem 0x6030000000-0x6031ffffff
64bit pref]: assigned
[ 598.839581] pci 0000:30:00.0: BAR 0 [mem 0x6e000000-0x6effffff]:
assigned
[ 598.840063] pci 0000:30:00.0: ROM [mem 0x6f000000-0x6f07ffff pref]:
assigned
[ 598.840538] pci 0000:30:00.1: BAR 0 [mem 0x6f080000-0x6f083fff]:
assigned
[ 598.841020] pci 0000:30:00.0: BAR 5 [io size 0x0080]: can't assign;
no space
[ 598.841496] pci 0000:30:00.0: BAR 5 [io size 0x0080]: failed to assign
[ 598.841974] pci 0000:30:00.0: BAR 5 [io size 0x0080]: can't assign;
no space
[ 598.842463] pci 0000:30:00.0: BAR 5 [io size 0x0080]: failed to assign
[ 598.842941] pci 0000:2f:01.0: PCI bridge to [bus 30]
[ 598.843429] pci 0000:2f:01.0: bridge window [mem
0x6e000000-0x720fffff]
[ 598.843918] pci 0000:2f:01.0: bridge window [mem
0x6020000000-0x6031ffffff 64bit pref]
[ 598.844415] pci 0000:2e:00.0: PCI bridge to [bus 2f-30]
[ 598.844901] pci 0000:2e:00.0: bridge window [mem
0x6e000000-0x720fffff]
[ 598.845388] pci 0000:2e:00.0: bridge window [mem
0x6020000000-0x6031ffffff 64bit pref]
[ 598.845890] pci 0000:2c:01.0: PCI bridge to [bus 2e-53]
[ 598.846369] pci 0000:2c:01.0: bridge window [mem
0x6e000000-0x720fffff]
[ 598.846845] pci 0000:2c:01.0: bridge window [mem
0x6020000000-0x6031ffffff 64bit pref]
[ 598.847319] pci 0000:2b:00.0: PCI bridge to [bus 2c-53]
[ 598.847789] pci 0000:2b:00.0: bridge window [mem
0x6e000000-0x7a0fffff]
[ 598.848255] pci 0000:2b:00.0: bridge window [mem
0x6020000000-0x6031ffffff 64bit pref]
[ 598.848720] pcieport 0000:00:07.1: PCI bridge to [bus 2b-53]
[ 598.849198] pcieport 0000:00:07.1: bridge window [mem
0x6e000000-0x7a1fffff]
[ 598.849667] pcieport 0000:00:07.1: bridge window [mem
0x6020000000-0x603bffffff 64bit pref]
[ 598.850136] PCI: No. 2 try to assign unassigned res
[ 598.850602] pci 0000:2c:00.0: disabling bridge window [mem
0x00000000-0x000fffff 64bit pref disabled] to [bus 2d] (unused)
[ 598.851083] pci 0000:2c:00.0: disabling bridge window [mem
0x00000000-0x000fffff disabled] to [bus 2d] (unused)
[ 598.851556] pci 0000:2c:01.0: bridge window [io size 0xab000] to
[bus 2e-53] add_size 155000
[ 598.852035] pci 0000:2b:00.0: bridge window [io size 0x200000] to
[bus 2c-53] add_size 155000
[ 598.852530] pcieport 0000:00:07.1: bridge window [io size 0x200000]
to [bus 2b-53] add_size 155000
[ 598.853014] pcieport 0000:00:07.1: bridge window [io size 0x355000]:
can't assign; no space
[ 598.853493] pcieport 0000:00:07.1: bridge window [io size 0x355000]:
failed to assign
[ 598.853971] pcieport 0000:00:07.1: bridge window [io size 0x200000]:
can't assign; no space
[ 598.854448] pcieport 0000:00:07.1: bridge window [io size 0x200000]:
failed to assign
[ 598.854921] pci 0000:2b:00.0: bridge window [io size 0x355000]:
can't assign; no space
[ 598.855401] pci 0000:2b:00.0: bridge window [io size 0x355000]:
failed to assign
[ 598.855896] pci 0000:2b:00.0: bridge window [io size 0x200000]:
can't assign; no space
[ 598.856376] pci 0000:2b:00.0: bridge window [io size 0x200000]:
failed to assign
[ 598.856847] pci 0000:2c:00.0: bridge window [io size 0x1000]: can't
assign; no space
[ 598.857319] pci 0000:2c:00.0: bridge window [io size 0x1000]: failed
to assign
[ 598.857788] pci 0000:2c:01.0: bridge window [io size 0x11c000]:
can't assign; no space
[ 598.858255] pci 0000:2c:01.0: bridge window [io size 0x11c000]:
failed to assign
[ 598.858722] pci 0000:2c:00.0: bridge window [io size 0x1000]: can't
assign; no space
[ 598.859209] pci 0000:2c:00.0: bridge window [io size 0x1000]: failed
to assign
[ 598.859677] pci 0000:2c:01.0: bridge window [io size 0x11c000]:
can't assign; no space
[ 598.860143] pci 0000:2c:01.0: bridge window [io size 0x11c000]:
failed to assign
[ 598.860609] pci 0000:2c:00.0: PCI bridge to [bus 2d]
[ 598.861088] pci 0000:2e:00.0: bridge window [io size 0x11c000]:
can't assign; no space
[ 598.861556] pci 0000:2e:00.0: bridge window [io size 0x11c000]:
failed to assign
[ 598.862018] pci 0000:2e:00.0: bridge window [io size 0x11c000]:
can't assign; no space
[ 598.862501] pci 0000:2e:00.0: bridge window [io size 0x11c000]:
failed to assign
[ 598.862970] pci 0000:2f:01.0: bridge window [io size 0x11c000]:
can't assign; no space
[ 598.863429] pci 0000:2f:01.0: bridge window [io size 0x11c000]:
failed to assign
[ 598.863891] pci 0000:2f:01.0: bridge window [io size 0x11c000]:
can't assign; no space
[ 598.864349] pci 0000:2f:01.0: bridge window [io size 0x11c000]:
failed to assign
[ 598.864802] pci 0000:30:00.0: BAR 5 [io size 0x0080]: can't assign;
no space
[ 598.865254] pci 0000:30:00.0: BAR 5 [io size 0x0080]: failed to assign
[ 598.865715] pci 0000:30:00.0: BAR 5 [io size 0x0080]: can't assign;
no space
[ 598.866163] pci 0000:30:00.0: BAR 5 [io size 0x0080]: failed to assign
[ 598.866615] pci 0000:2f:01.0: PCI bridge to [bus 30]
[ 598.867073] pci 0000:2f:01.0: bridge window [mem
0x6e000000-0x720fffff]
[ 598.867528] pci 0000:2f:01.0: bridge window [mem
0x6020000000-0x6031ffffff 64bit pref]
[ 598.867992] pci 0000:2e:00.0: PCI bridge to [bus 2f-30]
[ 598.868448] pci 0000:2e:00.0: bridge window [mem
0x6e000000-0x720fffff]
[ 598.868907] pci 0000:2e:00.0: bridge window [mem
0x6020000000-0x6031ffffff 64bit pref]
[ 598.869374] pci 0000:2c:01.0: PCI bridge to [bus 2e-53]
[ 598.869833] pci 0000:2c:01.0: bridge window [mem
0x6e000000-0x720fffff]
[ 598.870286] pci 0000:2c:01.0: bridge window [mem
0x6020000000-0x6031ffffff 64bit pref]
[ 598.870749] pci 0000:2b:00.0: PCI bridge to [bus 2c-53]
[ 598.871209] pci 0000:2b:00.0: bridge window [mem
0x6e000000-0x7a0fffff]
[ 598.871670] pci 0000:2b:00.0: bridge window [mem
0x6020000000-0x6031ffffff 64bit pref]
[ 598.872132] pcieport 0000:00:07.1: PCI bridge to [bus 2b-53]
[ 598.872613] pcieport 0000:00:07.1: bridge window [mem
0x6e000000-0x7a1fffff]
[ 598.873080] pcieport 0000:00:07.1: bridge window [mem
0x6020000000-0x603bffffff 64bit pref]
[ 598.873649] pcieport 0000:2b:00.0: enabling device (0000 -> 0002)
[ 598.874666] pcieport 0000:2c:01.0: enabling device (0000 -> 0002)
[ 598.875244] pcieport 0000:2c:01.0: pciehp: Slot #1 AttnBtn- PwrCtrl-
MRL- AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis-
LLActRep+
[ 598.876454] pcieport 0000:2c:02.0: pciehp: Hotplug bridge without
secondary bus, ignoring
[ 598.877284] pcieport 0000:2c:03.0: pciehp: Hotplug bridge without
secondary bus, ignoring
[ 598.878335] pcieport 0000:2e:00.0: enabling device (0000 -> 0002)
[ 598.879210] pcieport 0000:2f:01.0: enabling device (0000 -> 0002)
[ 598.880224] nvidia 0000:30:00.0: enabling device (0000 -> 0002)
[ 598.880833] nvidia 0000:30:00.0: vgaarb: VGA decodes changed:
olddecodes=io+mem,decodes=none:owns=none
[ 599.171370] [drm] [nvidia-drm] [GPU ID 0x00003000] Loading driver
[ 599.172273] [drm] Initialized nvidia-drm 0.0.0 for 0000:30:00.0 on
minor 3
[ 599.172936] pci 0000:30:00.1: extending delay after power-on from
D3hot to 20 msec
[ 599.173650] pci 0000:30:00.1: D0 power state depends on 0000:30:00.0
[ 683.104898] Loading firmware: nvidia/595.71.05/gsp_ga10x.bin
[ 683.634039] Loading firmware: nvidia/595.71.05/gsp_ga10x.bin
[ 684.043158] Loading firmware: nvidia/595.71.05/gsp_ga10x.bin
So, only one of the two hub-connected eGPUs are recognized.
pciehp: Hotplug bridge without secondary bus, ignoring <- This sounds
less promising.
lspci (after connecting hub):
00:00.0 Host bridge: Intel Corporation 12th Gen Core Processor Host
Bridge/DRAM Registers (rev 02)
00:02.0 VGA compatible controller: Intel Corporation Alder Lake-P GT2
[Iris Xe Graphics] (rev 0c)
00:04.0 Signal processing controller: Intel Corporation Alder Lake
Innovation Platform Framework Processor Participant (rev 02)
00:06.0 PCI bridge: Intel Corporation 12th Gen Core Processor PCI
Express x4 Controller #0 (rev 02)
00:07.0 PCI bridge: Intel Corporation Alder Lake-P Thunderbolt 4 PCI
Express Root Port #0 (rev 02)
00:07.1 PCI bridge: Intel Corporation Alder Lake-P Thunderbolt 4 PCI
Express Root Port #1 (rev 02)
00:07.2 PCI bridge: Intel Corporation Alder Lake-P Thunderbolt 4 PCI
Express Root Port #2 (rev 02)
00:07.3 PCI bridge: Intel Corporation Alder Lake-P Thunderbolt 4 PCI
Express Root Port #3 (rev 02)
00:08.0 System peripheral: Intel Corporation 12th Gen Core Processor
Gaussian & Neural Accelerator (rev 02)
00:0a.0 Signal processing controller: Intel Corporation Platform
Monitoring Technology (rev 01)
00:0d.0 USB controller: Intel Corporation Alder Lake-P Thunderbolt 4 USB
Controller (rev 02)
00:0d.2 USB controller: Intel Corporation Alder Lake-P Thunderbolt 4 NHI
#0 (rev 02)
00:0d.3 USB controller: Intel Corporation Alder Lake-P Thunderbolt 4 NHI
#1 (rev 02)
00:14.0 USB controller: Intel Corporation Alder Lake PCH USB 3.2 xHCI
Host Controller (rev 01)
00:14.2 RAM memory: Intel Corporation Alder Lake PCH Shared SRAM (rev 01)
00:15.0 Serial bus controller: Intel Corporation Alder Lake PCH Serial
IO I2C Controller #0 (rev 01)
00:15.1 Serial bus controller: Intel Corporation Alder Lake PCH Serial
IO I2C Controller #1 (rev 01)
00:15.3 Serial bus controller: Intel Corporation Alder Lake PCH Serial
IO I2C Controller #3 (rev 01)
00:16.0 Communication controller: Intel Corporation Alder Lake PCH HECI
Controller (rev 01)
00:16.3 Serial controller: Intel Corporation Alder Lake AMT SOL
Redirection (rev 01)
00:1d.0 PCI bridge: Intel Corporation Alder Lake PCI Express Root Port
#9 (rev 01)
00:1f.0 ISA bridge: Intel Corporation Alder Lake PCH eSPI Controller
(rev 01)
00:1f.3 Audio device: Intel Corporation Alder Lake PCH-P High Definition
Audio Controller (rev 01)
00:1f.4 SMBus: Intel Corporation Alder Lake PCH-P SMBus Host Controller
(rev 01)
00:1f.5 Serial bus controller: Intel Corporation Alder Lake-P PCH SPI
Controller (rev 01)
01:00.0 Non-Volatile memory controller: Samsung Electronics Co Ltd NVMe
SSD Controller PM9C1a (DRAM-less)
02:00.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C
step) [Alpine Ridge 2C 2016] (rev 02)
03:01.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C
step) [Alpine Ridge 2C 2016] (rev 02)
04:00.0 VGA compatible controller: NVIDIA Corporation GA102 [GeForce RTX
3090] (rev a1)
04:00.1 Audio device: NVIDIA Corporation GA102 High Definition Audio
Controller (rev a1)
2b:00.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
2020] (rev 03)
2c:00.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
2020] (rev 03)
2c:01.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
2020] (rev 03)
2c:02.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
2020] (rev 03)
2c:03.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
2020] (rev 03)
2c:04.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
2020] (rev 03)
2e:00.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C
step) [Alpine Ridge 2C 2016] (rev 02)
2f:01.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C
step) [Alpine Ridge 2C 2016] (rev 02)
30:00.0 VGA compatible controller: NVIDIA Corporation GA102 [GeForce RTX
3090] (rev a1)
30:00.1 Audio device: NVIDIA Corporation GA102 High Definition Audio
Controller (rev a1)
7d:00.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C
step) [Alpine Ridge 2C 2016] (rev 02)
7e:01.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C
step) [Alpine Ridge 2C 2016] (rev 02)
7f:00.0 VGA compatible controller: NVIDIA Corporation GA102 [GeForce RTX
3090 Ti] (rev a1)
7f:00.1 Audio device: NVIDIA Corporation GA102 High Definition Audio
Controller (rev a1)
a6:00.0 Ethernet controller: Intel Corporation Ethernet Controller
I226-V (rev 04)
/proc/iomem after connecting hub
00000000-00000fff : Reserved
00001000-0009efff : System RAM
0009f000-000fffff : Reserved
000a0000-000bffff : PCI Bus 0000:00
000f0000-000fffff : System ROM
00100000-3727bfff : System RAM
3727c000-372cafff : Reserved
372cb000-388b2fff : System RAM
388b3000-388b3fff : Reserved
388b4000-3b138fff : System RAM
3b139000-3ba38fff : Reserved
3ba39000-3d84efff : System RAM
3d84f000-40a7efff : Reserved
40a7f000-43a2efff : ACPI Non-volatile Storage
43945000-43945fff : USBC000:00
43a2f000-43afefff : ACPI Tables
43aff000-43afffff : System RAM
43b00000-47ffffff : Reserved
49200000-493fffff : Reserved
4a000000-503fffff : Reserved
4c800000-503fffff : Graphics Stolen Memory
50400000-bfffffff : PCI Bus 0000:00
50400000-50400fff : 0000:00:1f.5
50500000-507fffff : PCI Bus 0000:a6
50500000-505fffff : 0000:a6:00.0
50500000-505fffff : igc
50600000-506fffff : 0000:a6:00.0
50700000-50703fff : 0000:a6:00.0
50700000-50703fff : igc
52000000-5e1fffff : PCI Bus 0000:7d
52000000-5e0fffff : PCI Bus 0000:7e
52000000-5e0fffff : PCI Bus 0000:7f
52000000-52ffffff : 0000:7f:00.0
52000000-52ffffff : nvidia
53000000-5307ffff : 0000:7f:00.0
53080000-53083fff : 0000:7f:00.1
60000000-6c1fffff : PCI Bus 0000:54
6e000000-7a1fffff : PCI Bus 0000:2b
6e000000-7a0fffff : PCI Bus 0000:2c
6e000000-720fffff : PCI Bus 0000:2e
6e000000-720fffff : PCI Bus 0000:2f
6e000000-720fffff : PCI Bus 0000:30
6e000000-6effffff : 0000:30:00.0
6e000000-6effffff : nvidia
6f000000-6f07ffff : 0000:30:00.0
6f080000-6f083fff : 0000:30:00.1
7a400000-7a4fffff : PCI Bus 0000:01
7a400000-7a403fff : 0000:01:00.0
7a400000-7a403fff : nvme
7a600000-7a60ffff : 0000:00:14.0
7a600000-7a60ffff : xhci-hcd
7a611000-7a611fff : 0000:00:16.3
7c000000-881fffff : PCI Bus 0000:02
7c000000-880fffff : PCI Bus 0000:03
7c000000-880fffff : PCI Bus 0000:04
7c000000-7cffffff : 0000:04:00.0
7c000000-7cffffff : nvidia
7d000000-7d07ffff : 0000:04:00.0
7d080000-7d083fff : 0000:04:00.1
c0000000-cfffffff : PCI ECAM 0000 [bus 00-ff]
c0000000-cfffffff : PNP0C02:01
fd000000-fd68ffff : PNP0C02:02
fd690000-fd69ffff : INTC1055:00
fd6a0000-fd6affff : INTC1055:00
fd6b0000-fd6cffff : PNP0C02:02
fd6d0000-fd6dffff : INTC1055:00
fd6e0000-fd6effff : INTC1055:00
fd6f0000-fdffffff : PNP0C02:02
fe000000-fe01ffff : PNP0C02:02
fe04c000-fe04ffff : PNP0C02:02
fe050000-fe0affff : PNP0C02:02
fe0d0000-fe0fffff : PNP0C02:02
fe200000-fe7fffff : PNP0C02:02
fec00000-fec003ff : IOAPIC 0
fed00000-fed003ff : HPET 0
fed00000-fed003ff : PNP0103:00
fed20000-fed7ffff : Reserved
fed40000-fed44fff : NTC0702:00
fed90000-fed90fff : dmar0
fed91000-fed91fff : dmar1
feda0000-feda0fff : PNP0C02:01
feda1000-feda1fff : PNP0C02:01
fedc0000-fedc7fff : PNP0C02:01
fee00000-feefffff : PNP0C02:01
ff000000-ffffffff : PNP0C02:02
100000000-10afbfffff : System RAM
d6a000000-d6b1e52f7 : Kernel code
d6b200000-d6b7a0fff : Kernel rodata
d6b800000-d6bac0cff : Kernel data
d6c247000-d6c30ffff : Kernel bss
10afc00000-10afffffff : RAM buffer
4000000000-7fffffffff : PCI Bus 0000:00
4000000000-400fffffff : 0000:00:02.0
4010000000-4016ffffff : 0000:00:02.0
4017000000-4017000fff : 0000:00:15.0
4017000000-40170001ff : lpss_dev
4017000000-40170001ff : i2c_designware.0 lpss_dev
4017000200-40170002ff : lpss_priv
4017000800-4017000fff : idma64.0
4017001000-4017001fff : 0000:00:15.1
4017001000-40170011ff : lpss_dev
4017001000-40170011ff : i2c_designware.1 lpss_dev
4017001200-40170012ff : lpss_priv
4017001800-4017001fff : idma64.1
4017002000-4017002fff : 0000:00:15.3
4017002000-40170021ff : lpss_dev
4017002000-40170021ff : i2c_designware.2 lpss_dev
4017002200-40170022ff : lpss_priv
4017002800-4017002fff : idma64.2
4020000000-40ffffffff : 0000:00:02.0
6000000000-601bffffff : PCI Bus 0000:02
6000000000-6011ffffff : PCI Bus 0000:03
6000000000-6011ffffff : PCI Bus 0000:04
6000000000-600fffffff : 0000:04:00.0
6010000000-6011ffffff : 0000:04:00.0
6020000000-603bffffff : PCI Bus 0000:2b
6020000000-6031ffffff : PCI Bus 0000:2c
6020000000-6031ffffff : PCI Bus 0000:2e
6020000000-6031ffffff : PCI Bus 0000:2f
6020000000-6031ffffff : PCI Bus 0000:30
6020000000-602fffffff : 0000:30:00.0
6030000000-6031ffffff : 0000:30:00.0
6040000000-605bffffff : PCI Bus 0000:54
605c000000-605cffffff : 0000:00:02.0
605d000000-605d0fffff : 0000:00:1f.3
605d100000-605d13ffff : 0000:00:0d.3
605d100000-605d13ffff : thunderbolt
605d140000-605d17ffff : 0000:00:0d.2
605d140000-605d17ffff : thunderbolt
605d180000-605d19ffff : 0000:00:04.0
605d180000-605d19ffff : proc_thermal
605d1a0000-605d1affff : 0000:00:0d.0
605d1a0000-605d1affff : xhci-hcd
605d1b0000-605d1b7fff : 0000:00:0a.0
605d1b8000-605d1bbfff : 0000:00:1f.3
605d1bc000-605d1bffff : 0000:00:14.2
605d1c0000-605d1c00ff : 0000:00:1f.4
605d1c0000-605d1c00ff : i801_smbus
605d1c1000-605d1c1fff : 0000:00:16.0
605d1c1000-605d1c1fff : mei_me
605d1c5000-605d1c5fff : 0000:00:14.2
605d1c6000-605d1c6fff : 0000:00:0d.3
605d1c7000-605d1c7fff : 0000:00:0d.2
605d1c8000-605d1c8fff : 0000:00:08.0
6060000000-607bffffff : PCI Bus 0000:7d
6060000000-6071ffffff : PCI Bus 0000:7e
6060000000-6071ffffff : PCI Bus 0000:7f
6060000000-606fffffff : 0000:7f:00.0
6070000000-6071ffffff : 0000:7f:00.0
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Connecting multiple TB3 eGPUs via USB4 hub?'
2026-05-24 14:56 Connecting multiple TB3 eGPUs via USB4 hub? Dag B
@ 2026-06-08 15:26 ` Bjorn Helgaas
2026-06-09 12:08 ` Mika Westerberg
0 siblings, 1 reply; 6+ messages in thread
From: Bjorn Helgaas @ 2026-06-08 15:26 UTC (permalink / raw)
To: Dag B; +Cc: linux-pci, linux-usb, Ilpo Järvinen, Lukas Wunner
[+cc linux-usb (Thunderbolt maintainers), Ilpo, Lukas]
On Sun, May 24, 2026 at 04:56:56PM +0200, Dag B wrote:
> I am attempting to connect two TB3 enclosures to the same USB4 port via a
> USB4 hub.
>
> I cannot figure out of this is in violation of the TB3, TB4 or USB4 spec.
I'm not aware of a spec issue here.
Below it looks like you hot-added the hub. Does it make any
difference if everything is connected before boot?
Please don't filter the dmesg logs you collect. We can do that if
needed.
> .... or, in case it is not:
>
> Can this work with current USB4/Thunderbolt drivers in Linux? (I am not
> worried about bandwidth limitations.)
>
>
> This appears to be too niche to find answers anywhere else. I would be very
> grateful for any clarifying answer here, really.
>
>
> Hardware
>
> - Framework 13 mb with 12th gen Alder Lake (Intel Corporation Alder Lake-P
> Thunderbolt 4 NHI) (4 USB4 ports)
>
> - Sonnettech Echo 5 hub (Intel Corporation Thunderbolt 4 Bridge [Goshen
> Ridge 2020] )
>
> - Razer Core X (Intel Corporation JHL6340 Thunderbolt 3 Bridge (C step)
> [Alpine Ridge 2C 2016])
>
> - GPUs are Nvidia RTX 3090. They expose two PCIe devices, the GPU and an
> audio device.
>
>
> Using kernel 7.0.10 with gentoo patches.
>
>
> Been playing *a lot* with various permutations of pci-related kernel
> options. Current options:
>
> pci=realloc=on,hpmmiosize=256M,hpiosize=2M,hpmemsize=1G,hpbussize=0x33,pcie_scan_all,big_root_window
>
>
> pcie_port_pm=off
>
> pcie_aspm.policy=performance
>
> thunderbolt.clx=0
>
>
>
> Booting with 2 eGPUS directly connected to separate USB4 ports. (pcie
> messages only):
>
> [ 0.000000] Command line: root=/dev/nvme0n1p2 pci=realloc=on,hpmmiosize=256M,hpiosize=2M,hpmemsize=1G,hpbussize=0x33,pcie_scan_all,big_root_window
> pcie_port_pm=off pcie_aspm.policy=performance thunderbolt.clx=0
> [ 0.082296] Kernel command line: pci=realloc=on,hpmmiosize=256M,hpiosize=2M,hpmemsize=1G,hpbussize=0x33,pcie_scan_all,big_root_window
> \
> [ 0.082297] Kernel command line: pcie_port_pm=off
> pcie_aspm.policy=performance \
> [ 0.864174] pcieport 0000:00:06.0: PME: Signaling with IRQ 122
> [ 0.864343] pcieport 0000:00:07.0: PME: Signaling with IRQ 123
> [ 0.864358] pcieport 0000:00:07.0: pciehp: Slot #3 AttnBtn- PwrCtrl- MRL-
> AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis- LLActRep+
> [ 0.864661] pcieport 0000:00:07.1: PME: Signaling with IRQ 124
> [ 0.864677] pcieport 0000:00:07.1: pciehp: Slot #4 AttnBtn- PwrCtrl- MRL-
> AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis- LLActRep+
> [ 0.864900] pcieport 0000:00:07.2: PME: Signaling with IRQ 125
> [ 0.864914] pcieport 0000:00:07.2: pciehp: Slot #5 AttnBtn- PwrCtrl- MRL-
> AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis- LLActRep+
> [ 0.865139] pcieport 0000:00:07.3: PME: Signaling with IRQ 126
> [ 0.865153] pcieport 0000:00:07.3: pciehp: Slot #6 AttnBtn- PwrCtrl- MRL-
> AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis- LLActRep+
> [ 0.865376] pcieport 0000:00:1d.0: PME: Signaling with IRQ 127
> [ 5.127515] pcieport 0000:00:07.3: pciehp: Slot(6): Card present
> [ 5.134225] pcieport 0000:00:07.0: pciehp: Slot(3): Card present
> [ 5.263158] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
> can't assign; no space
> [ 5.263178] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
> failed to assign
> [ 5.263197] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
> can't assign; no space
> [ 5.263215] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
> failed to assign
> [ 5.270527] pcieport 0000:00:07.3: PCI bridge to [bus 7d-a5]
> [ 5.270529] pcieport 0000:00:07.3: bridge window [mem
> 0x52000000-0x5e1fffff]
> [ 5.270531] pcieport 0000:00:07.3: bridge window [mem
> 0x6060000000-0x607bffffff 64bit pref]
> [ 5.270537] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
> can't assign; no space
> [ 5.270537] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
> failed to assign
> [ 5.270538] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
> can't assign; no space
> [ 5.270539] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
> failed to assign
> [ 5.270577] pcieport 0000:00:07.3: PCI bridge to [bus 7d-a5]
> [ 5.270579] pcieport 0000:00:07.3: bridge window [mem
> 0x52000000-0x5e1fffff]
> [ 5.270581] pcieport 0000:00:07.3: bridge window [mem
> 0x6060000000-0x607bffffff 64bit pref]
> [ 5.270703] pcieport 0000:7d:00.0: enabling device (0000 -> 0002)
> [ 5.287127] pcieport 0000:7e:01.0: enabling device (0000 -> 0002)
> [ 5.325065] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
> can't assign; no space
> [ 5.325560] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
> failed to assign
> [ 5.326061] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
> can't assign; no space
> [ 5.326560] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
> failed to assign
> [ 5.340678] pcieport 0000:00:07.0: PCI bridge to [bus 02-2a]
> [ 5.340680] pcieport 0000:00:07.0: bridge window [mem
> 0x7c000000-0x881fffff]
> [ 5.340682] pcieport 0000:00:07.0: bridge window [mem
> 0x6000000000-0x601bffffff 64bit pref]
> [ 5.340688] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
> can't assign; no space
> [ 5.340689] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
> failed to assign
> [ 5.340690] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
> can't assign; no space
> [ 5.340690] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
> failed to assign
> [ 5.340741] pcieport 0000:00:07.0: PCI bridge to [bus 02-2a]
> [ 5.340744] pcieport 0000:00:07.0: bridge window [mem
> 0x7c000000-0x881fffff]
> [ 5.340745] pcieport 0000:00:07.0: bridge window [mem
> 0x6000000000-0x601bffffff 64bit pref]
> [ 5.340866] pcieport 0000:02:00.0: enabling device (0000 -> 0002)
> [ 5.355410] pcieport 0000:03:01.0: enabling device (0000 -> 0002)
>
>
> Then, connecting the hub with two additional eGPUs to a third USB4 port (all
> messages):
>
> [ 596.449718] thunderbolt 0-3: new device found, vendor=0x8 device=0x5f
> [ 596.449771] thunderbolt 0-3: Sonnet Technologies, Inc. Echo 5 Thunderbolt
> 4 Hub
> [ 596.710380] thunderbolt 0-0:3.1: new retimer found, vendor=0x8087
> device=0x15ee
> [ 596.962295] usb 3-3: new high-speed USB device number 4 using xhci_hcd
> [ 597.156102] usb 3-3: New USB device found, idVendor=1d5c, idProduct=5801,
> bcdDevice= 1.01
> [ 597.156118] usb 3-3: New USB device strings: Mfr=1, Product=2,
> SerialNumber=0
> [ 597.156130] usb 3-3: Product: USB2.0 Hub
> [ 597.156138] usb 3-3: Manufacturer: Fresco Logic, Inc.
> [ 597.157120] hub 3-3:1.0: USB hub found
> [ 597.157152] hub 3-3:1.0: 6 ports detected
> [ 597.458933] usb 2-2: new SuperSpeed Plus Gen 2x1 USB device number 4
> using xhci_hcd
> [ 597.472670] usb 2-2: New USB device found, idVendor=8087, idProduct=0b40,
> bcdDevice=12.34
> [ 597.472687] usb 2-2: New USB device strings: Mfr=1, Product=2,
> SerialNumber=0
> [ 597.472700] usb 2-2: Product: USB3.0 Hub
> [ 597.472711] usb 2-2: Manufacturer: Intel Corporation.
> [ 597.473459] hub 2-2:1.0: USB hub found
> [ 597.473587] hub 2-2:1.0: 4 ports detected
> [ 597.559335] thunderbolt 0-303: new device found, vendor=0x127 device=0x1
> [ 597.559350] thunderbolt 0-303: Razer Core X
> [ 597.702310] usb 3-3.5: new full-speed USB device number 5 using xhci_hcd
> [ 597.801389] usb 3-3.5: New USB device found, idVendor=2a8c,
> idProduct=205f, bcdDevice=17.46
> [ 597.801406] usb 3-3.5: New USB device strings: Mfr=1, Product=2,
> SerialNumber=3
> [ 597.801418] usb 3-3.5: Product: Echo 5 Thunderbolt 4 Hub
> [ 597.801428] usb 3-3.5: Manufacturer: Sonnet Technologies,Inc.
> [ 597.801438] usb 3-3.5: SerialNumber: 11AD1D0A510D2E0D381E0B00
> [ 597.885632] usb 3-3.6: new high-speed USB device number 6 using xhci_hcd
> [ 597.983768] usb 3-3.6: New USB device found, idVendor=1d5c,
> idProduct=5530, bcdDevice= 1.01
> [ 597.983785] usb 3-3.6: New USB device strings: Mfr=1, Product=2,
> SerialNumber=0
> [ 597.983798] usb 3-3.6: Product: Frescologic VENDOR HID
> [ 597.983807] usb 3-3.6: Manufacturer: Frescologic
> [ 597.985769] hid-generic 0003:1D5C:5530.0002: hidraw1: USB HID v1.01
> Device [Frescologic Frescologic VENDOR HID] on usb-0000:00:14.0-3.6/input0
> [ 598.294042] thunderbolt 0-503: new device found, vendor=0x127 device=0x1
> [ 598.294057] thunderbolt 0-503: Razer Core X
> [ 598.619985] pcieport 0000:00:07.1: pciehp: Slot(4): Card present
> [ 598.619999] pcieport 0000:00:07.1: pciehp: Slot(4): Link Up
> [ 598.745860] pci 0000:2b:00.0: [8086:0b26] type 01 class 0x060400 PCIe
> Switch Upstream Port
> [ 598.745987] pci 0000:2b:00.0: PCI bridge to [bus 00]
> [ 598.746028] pci 0000:2b:00.0: bridge window [io 0x0000-0x0fff]
> [ 598.746061] pci 0000:2b:00.0: bridge window [mem 0x00000000-0x000fffff]
> [ 598.746113] pci 0000:2b:00.0: bridge window [mem 0x00000000-0x000fffff
> 64bit pref]
> [ 598.746173] pci 0000:2b:00.0: enabling Extended Tags
> [ 598.746450] pci 0000:2b:00.0: supports D1 D2
> [ 598.746471] pci 0000:2b:00.0: PME# supported from D0 D1 D2 D3hot D3cold
> [ 598.747002] pci 0000:2b:00.0: Adding to iommu group 22
> [ 598.755705] pci 0000:2b:00.0: bridge configuration invalid ([bus 00-00]),
> reconfiguring
> [ 598.755945] pci 0000:2c:00.0: [8086:0b26] type 01 class 0x060400 PCIe
> Switch Downstream Port
> [ 598.756014] pci 0000:2c:00.0: PCI bridge to [bus 00]
> [ 598.756039] pci 0000:2c:00.0: bridge window [io 0x0000-0x0fff]
> [ 598.756059] pci 0000:2c:00.0: bridge window [mem 0x00000000-0x000fffff]
> [ 598.756094] pci 0000:2c:00.0: bridge window [mem 0x00000000-0x000fffff
> 64bit pref]
> [ 598.756136] pci 0000:2c:00.0: enabling Extended Tags
> [ 598.756346] pci 0000:2c:00.0: supports D1 D2
> [ 598.756359] pci 0000:2c:00.0: PME# supported from D0 D1 D2 D3hot D3cold
> [ 598.756675] pci 0000:2c:00.0: Adding to iommu group 23
> [ 598.756854] pci 0000:2c:01.0: [8086:0b26] type 01 class 0x060400 PCIe
> Switch Downstream Port
> [ 598.756925] pci 0000:2c:01.0: PCI bridge to [bus 00]
> [ 598.756950] pci 0000:2c:01.0: bridge window [io 0x0000-0x0fff]
> [ 598.756970] pci 0000:2c:01.0: bridge window [mem 0x00000000-0x000fffff]
> [ 598.757863] pci 0000:2c:01.0: bridge window [mem 0x00000000-0x000fffff
> 64bit pref]
> [ 598.758743] pci 0000:2c:01.0: enabling Extended Tags
> [ 598.759822] pci 0000:2c:01.0: supports D1 D2
> [ 598.760599] pci 0000:2c:01.0: PME# supported from D0 D1 D2 D3hot D3cold
> [ 598.761582] pci 0000:2c:01.0: Adding to iommu group 24
> [ 598.762477] pci 0000:2c:02.0: [8086:0b26] type 01 class 0x060400 PCIe
> Switch Downstream Port
> [ 598.763270] pci 0000:2c:02.0: PCI bridge to [bus 00]
> [ 598.764010] pci 0000:2c:02.0: bridge window [io 0x0000-0x0fff]
> [ 598.764697] pci 0000:2c:02.0: bridge window [mem 0x00000000-0x000fffff]
> [ 598.765266] pci 0000:2c:02.0: bridge window [mem 0x00000000-0x000fffff
> 64bit pref]
> [ 598.765832] pci 0000:2c:02.0: enabling Extended Tags
> [ 598.766513] pci 0000:2c:02.0: supports D1 D2
> [ 598.767016] pci 0000:2c:02.0: PME# supported from D0 D1 D2 D3hot D3cold
> [ 598.767686] pci 0000:2c:02.0: Adding to iommu group 25
> [ 598.768272] pci 0000:2c:03.0: [8086:0b26] type 01 class 0x060400 PCIe
> Switch Downstream Port
> [ 598.768804] pci 0000:2c:03.0: PCI bridge to [bus 00]
> [ 598.769323] pci 0000:2c:03.0: bridge window [io 0x0000-0x0fff]
> [ 598.769815] pci 0000:2c:03.0: bridge window [mem 0x00000000-0x000fffff]
> [ 598.770317] pci 0000:2c:03.0: bridge window [mem 0x00000000-0x000fffff
> 64bit pref]
> [ 598.770816] pci 0000:2c:03.0: enabling Extended Tags
> [ 598.771451] pci 0000:2c:03.0: supports D1 D2
> [ 598.771929] pci 0000:2c:03.0: PME# supported from D0 D1 D2 D3hot D3cold
> [ 598.772596] pci 0000:2c:03.0: Adding to iommu group 26
> [ 598.773173] pci 0000:2c:04.0: [8086:0b26] type 01 class 0x060400 PCIe
> Switch Downstream Port
> [ 598.773694] pci 0000:2c:04.0: PCI bridge to [bus 00]
> [ 598.774196] pci 0000:2c:04.0: bridge window [io 0x0000-0x0fff]
> [ 598.774683] pci 0000:2c:04.0: bridge window [mem 0x00000000-0x000fffff]
> [ 598.775179] pci 0000:2c:04.0: bridge window [mem 0x00000000-0x000fffff
> 64bit pref]
> [ 598.775687] pci 0000:2c:04.0: enabling Extended Tags
> [ 598.776319] pci 0000:2c:04.0: supports D1 D2
> [ 598.776794] pci 0000:2c:04.0: PME# supported from D0 D1 D2 D3hot D3cold
> [ 598.777437] pci 0000:2c:04.0: Adding to iommu group 27
> [ 598.777985] pci 0000:2b:00.0: PCI bridge to [bus 2c-53]
> [ 598.778481] pci 0000:2c:00.0: bridge configuration invalid ([bus 00-00]),
> reconfiguring
> [ 598.778983] pci 0000:2c:01.0: bridge configuration invalid ([bus 00-00]),
> reconfiguring
> [ 598.779463] pci 0000:2c:02.0: bridge configuration invalid ([bus 00-00]),
> reconfiguring
> [ 598.779939] pci 0000:2c:03.0: bridge configuration invalid ([bus 00-00]),
> reconfiguring
> [ 598.780408] pci 0000:2c:04.0: bridge configuration invalid ([bus 00-00]),
> reconfiguring
> [ 598.780987] pci 0000:2c:00.0: PCI bridge to [bus 2d-53]
> [ 598.781458] pci_bus 0000:2d: busn_res: [bus 2d-53] end is updated to 2d
> [ 598.782096] pci 0000:2e:00.0: [8086:15da] type 01 class 0x060400 PCIe
> Switch Upstream Port
> [ 598.782628] pci 0000:2e:00.0: PCI bridge to [bus 00]
> [ 598.783089] pci 0000:2e:00.0: bridge window [io 0x0000-0x0fff]
> [ 598.783548] pci 0000:2e:00.0: bridge window [mem 0x00000000-0x000fffff]
> [ 598.784020] pci 0000:2e:00.0: bridge window [mem 0x00000000-0x000fffff
> 64bit pref]
> [ 598.784493] pci 0000:2e:00.0: enabling Extended Tags
> [ 598.785172] pci 0000:2e:00.0: supports D1 D2
> [ 598.785624] pci 0000:2e:00.0: PME# supported from D0 D1 D2 D3hot D3cold
> [ 598.786319] pci 0000:2e:00.0: Adding to iommu group 28
> [ 598.792407] pci 0000:2c:01.0: PCI bridge to [bus 2e-53]
> [ 598.792880] pci 0000:2e:00.0: bridge configuration invalid ([bus 00-00]),
> reconfiguring
> [ 598.793579] pci 0000:2f:01.0: [8086:15da] type 01 class 0x060400 PCIe
> Switch Downstream Port
> [ 598.794094] pci 0000:2f:01.0: PCI bridge to [bus 00]
> [ 598.794559] pci 0000:2f:01.0: bridge window [io 0x0000-0x0fff]
> [ 598.795014] pci 0000:2f:01.0: bridge window [mem 0x00000000-0x000fffff]
> [ 598.795485] pci 0000:2f:01.0: bridge window [mem 0x00000000-0x000fffff
> 64bit pref]
> [ 598.795981] pci 0000:2f:01.0: enabling Extended Tags
> [ 598.796665] pci 0000:2f:01.0: supports D1 D2
> [ 598.797111] pci 0000:2f:01.0: PME# supported from D0 D1 D2 D3hot D3cold
> [ 598.797785] pci 0000:2f:01.0: Adding to iommu group 29
> [ 598.798344] pci 0000:2e:00.0: PCI bridge to [bus 2f-53]
> [ 598.798826] pci 0000:2f:01.0: bridge configuration invalid ([bus 00-00]),
> reconfiguring
> [ 598.799576] pci 0000:30:00.0: [10de:2204] type 00 class 0x030000 PCIe
> Legacy Endpoint
> [ 598.800146] pci 0000:30:00.0: BAR 0 [mem 0x00000000-0x00ffffff]
> [ 598.800598] pci 0000:30:00.0: BAR 1 [mem 0x00000000-0x0fffffff 64bit
> pref]
> [ 598.801062] pci 0000:30:00.0: BAR 3 [mem 0x00000000-0x01ffffff 64bit
> pref]
> [ 598.801512] pci 0000:30:00.0: BAR 5 [io 0x0000-0x007f]
> [ 598.801961] pci 0000:30:00.0: ROM [mem 0x00000000-0x0007ffff pref]
> [ 598.802697] pci 0000:30:00.0: PME# supported from D0 D3hot
> [ 598.803421] pci 0000:30:00.0: 8.000 Gb/s available PCIe bandwidth,
> limited by 2.5 GT/s PCIe x4 link at 0000:00:07.1 (capable of 252.048 Gb/s
> with 16.0 GT/s PCIe x16 link)
> [ 598.804053] pci 0000:30:00.0: Adding to iommu group 29
> [ 598.804517] pci 0000:30:00.0: vgaarb: bridge control possible
> [ 598.804969] pci 0000:30:00.0: vgaarb: VGA device added:
> decodes=io+mem,owns=none,locks=none
> [ 598.805427] i915 0000:00:02.0: vgaarb: VGA decodes changed:
> olddecodes=none,decodes=none:owns=io+mem
> [ 598.806033] pci 0000:30:00.1: [10de:1aef] type 00 class 0x040300 PCIe
> Endpoint
> [ 598.806622] pci 0000:30:00.1: BAR 0 [mem 0x00000000-0x00003fff]
> [ 598.807434] pci 0000:30:00.1: Adding to iommu group 29
> [ 598.808118] pci 0000:2f:01.0: PCI bridge to [bus 30-53]
> [ 598.808614] pci_bus 0000:30: busn_res: [bus 30-53] end is updated to 30
> [ 598.809107] pci_bus 0000:2f: busn_res: [bus 2f-53] end is updated to 30
> [ 598.809575] pci_bus 0000:2e: busn_res: [bus 2e-53] end is updated to 53
> [ 598.810077] pci_bus 0000:54: busn_res: [bus 54-7c] end is updated to 7c
> [ 598.810714] pci_bus 0000:7d: busn_res: [bus 7d-a5] end is updated to a5
> [ 598.811226] pci_bus 0000:a6: busn_res: [bus a6] end is updated to a6
> [ 598.811682] pci_bus 0000:2c: busn_res: [bus 2c-53] end can not be updated
> to a6
> [ 598.812141] pci 0000:2c:00.0: disabling bridge window [mem
> 0x00000000-0x000fffff 64bit pref] to [bus 2d] (unused)
> [ 598.812621] pci 0000:2c:00.0: disabling bridge window [mem
> 0x00000000-0x000fffff] to [bus 2d] (unused)
> [ 598.813082] pci 0000:2c:01.0: bridge window [io 0x1000-0x1fff] to [bus
> 2e-53] add_size 1ff000
> [ 598.813544] pci 0000:2c:01.0: bridge window [mem 0x10000000-0x21ffffff
> 64bit pref] to [bus 2e-53] add_size 2e000000 add_align 10000000
> [ 598.814007] pci 0000:2c:01.0: bridge window [mem 0x01000000-0x020fffff]
> to [bus 2e-53] add_size 3ef00000 add_align 1000000
> [ 598.814474] pci 0000:2b:00.0: bridge window [io 0x1000-0x2fff] to [bus
> 2c-53] add_size 1ff000
> [ 598.814942] pci 0000:2b:00.0: bridge window [mem 0x10000000-0x21ffffff
> 64bit pref] to [bus 2c-53] add_size 2e000000 add_align 10000000
> [ 598.815414] pci 0000:2b:00.0: bridge window [mem 0x01000000-0x020fffff]
> to [bus 2c-53] add_size 3ef00000 add_align 1000000
> [ 598.815908] pcieport 0000:00:07.1: bridge window [io size 0x200000] to
> [bus 2b-53] add_size 1ff000
> [ 598.816393] pcieport 0000:00:07.1: bridge window [io size 0x3ff000]:
> can't assign; no space
> [ 598.816870] pcieport 0000:00:07.1: bridge window [io size 0x3ff000]:
> failed to assign
> [ 598.817346] pcieport 0000:00:07.1: bridge window [io size 0x200000]:
> can't assign; no space
> [ 598.817828] pcieport 0000:00:07.1: bridge window [io size 0x200000]:
> failed to assign
> [ 598.818304] pci 0000:2b:00.0: bridge window [mem size 0x40000000 64bit
> pref]: can't assign; no space
> [ 598.818785] pci 0000:2b:00.0: bridge window [mem size 0x40000000 64bit
> pref]: failed to assign
> [ 598.819281] pci 0000:2b:00.0: bridge window [mem 0x6e000000-0x7a0fffff]:
> assigned
> [ 598.819765] pci 0000:2b:00.0: bridge window [io size 0x200000]: can't
> assign; no space
> [ 598.820250] pci 0000:2b:00.0: bridge window [io size 0x200000]: failed
> to assign
> [ 598.820740] pci 0000:2b:00.0: bridge window [mem 0x6e000000-0x7a0fffff]:
> releasing
> [ 598.821235] pci 0000:2b:00.0: bridge window [mem
> 0x6020000000-0x6031ffffff 64bit pref]: assigned
> [ 598.821727] pci 0000:2b:00.0: bridge window [mem 0x6e000000-0x7a0fffff]:
> assigned
> [ 598.822227] pci 0000:2b:00.0: bridge window [io size 0x200000]: can't
> assign; no space
> [ 598.822722] pci 0000:2b:00.0: bridge window [io size 0x200000]: failed
> to assign
> [ 598.823206] pci 0000:2b:00.0: bridge window [mem
> 0x6020000000-0x6031ffffff 64bit pref]: failed to expand by 0x2e000000
> [ 598.823697] pci 0000:2b:00.0: bridge window [mem
> 0x6020000000-0x6031ffffff 64bit pref]: failed to add optional 2e000000
> [ 598.824186] pci 0000:2c:01.0: bridge window [mem size 0x40000000 64bit
> pref]: can't assign; no space
> [ 598.824679] pci 0000:2c:01.0: bridge window [mem size 0x40000000 64bit
> pref]: failed to assign
> [ 598.825173] pci 0000:2c:01.0: bridge window [mem 0x6e000000-0x720fffff]:
> assigned
> [ 598.825677] pci 0000:2c:00.0: bridge window [io size 0x1000]: can't
> assign; no space
> [ 598.826173] pci 0000:2c:00.0: bridge window [io size 0x1000]: failed to
> assign
> [ 598.826666] pci 0000:2c:01.0: bridge window [io size 0xab000]: can't
> assign; no space
> [ 598.827161] pci 0000:2c:01.0: bridge window [io size 0xab000]: failed to
> assign
> [ 598.827652] pci 0000:2c:01.0: bridge window [mem 0x6e000000-0x720fffff]:
> releasing
> [ 598.828140] pci 0000:2c:01.0: bridge window [mem
> 0x6020000000-0x6031ffffff 64bit pref]: assigned
> [ 598.828630] pci 0000:2c:01.0: bridge window [mem 0x6e000000-0x720fffff]:
> assigned
> [ 598.829132] pci 0000:2c:00.0: bridge window [io size 0x1000]: can't
> assign; no space
> [ 598.829623] pci 0000:2c:00.0: bridge window [io size 0x1000]: failed to
> assign
> [ 598.830116] pci 0000:2c:01.0: bridge window [io size 0xab000]: can't
> assign; no space
> [ 598.830606] pci 0000:2c:01.0: bridge window [io size 0xab000]: failed to
> assign
> [ 598.831099] pci 0000:2c:01.0: bridge window [mem
> 0x6020000000-0x6031ffffff 64bit pref]: failed to expand by 0x2e000000
> [ 598.831588] pci 0000:2c:01.0: bridge window [mem
> 0x6020000000-0x6031ffffff 64bit pref]: failed to add optional 2e000000
> [ 598.832080] pci 0000:2c:00.0: PCI bridge to [bus 2d]
> [ 598.832605] pci 0000:2e:00.0: bridge window [mem
> 0x6020000000-0x6031ffffff 64bit pref]: assigned
> [ 598.833106] pci 0000:2e:00.0: bridge window [mem 0x6e000000-0x720fffff]:
> assigned
> [ 598.833599] pci 0000:2e:00.0: bridge window [io size 0xab000]: can't
> assign; no space
> [ 598.834091] pci 0000:2e:00.0: bridge window [io size 0xab000]: failed to
> assign
> [ 598.834590] pci 0000:2e:00.0: bridge window [io size 0xab000]: can't
> assign; no space
> [ 598.835088] pci 0000:2e:00.0: bridge window [io size 0xab000]: failed to
> assign
> [ 598.835592] pci 0000:2f:01.0: bridge window [mem
> 0x6020000000-0x6031ffffff 64bit pref]: assigned
> [ 598.836098] pci 0000:2f:01.0: bridge window [mem 0x6e000000-0x720fffff]:
> assigned
> [ 598.836600] pci 0000:2f:01.0: bridge window [io size 0xab000]: can't
> assign; no space
> [ 598.837097] pci 0000:2f:01.0: bridge window [io size 0xab000]: failed to
> assign
> [ 598.837585] pci 0000:2f:01.0: bridge window [io size 0xab000]: can't
> assign; no space
> [ 598.838073] pci 0000:2f:01.0: bridge window [io size 0xab000]: failed to
> assign
> [ 598.838559] pci 0000:30:00.0: BAR 1 [mem 0x6020000000-0x602fffffff 64bit
> pref]: assigned
> [ 598.839079] pci 0000:30:00.0: BAR 3 [mem 0x6030000000-0x6031ffffff 64bit
> pref]: assigned
> [ 598.839581] pci 0000:30:00.0: BAR 0 [mem 0x6e000000-0x6effffff]: assigned
> [ 598.840063] pci 0000:30:00.0: ROM [mem 0x6f000000-0x6f07ffff pref]:
> assigned
> [ 598.840538] pci 0000:30:00.1: BAR 0 [mem 0x6f080000-0x6f083fff]: assigned
> [ 598.841020] pci 0000:30:00.0: BAR 5 [io size 0x0080]: can't assign; no
> space
> [ 598.841496] pci 0000:30:00.0: BAR 5 [io size 0x0080]: failed to assign
> [ 598.841974] pci 0000:30:00.0: BAR 5 [io size 0x0080]: can't assign; no
> space
> [ 598.842463] pci 0000:30:00.0: BAR 5 [io size 0x0080]: failed to assign
> [ 598.842941] pci 0000:2f:01.0: PCI bridge to [bus 30]
> [ 598.843429] pci 0000:2f:01.0: bridge window [mem 0x6e000000-0x720fffff]
> [ 598.843918] pci 0000:2f:01.0: bridge window [mem
> 0x6020000000-0x6031ffffff 64bit pref]
> [ 598.844415] pci 0000:2e:00.0: PCI bridge to [bus 2f-30]
> [ 598.844901] pci 0000:2e:00.0: bridge window [mem 0x6e000000-0x720fffff]
> [ 598.845388] pci 0000:2e:00.0: bridge window [mem
> 0x6020000000-0x6031ffffff 64bit pref]
> [ 598.845890] pci 0000:2c:01.0: PCI bridge to [bus 2e-53]
> [ 598.846369] pci 0000:2c:01.0: bridge window [mem 0x6e000000-0x720fffff]
> [ 598.846845] pci 0000:2c:01.0: bridge window [mem
> 0x6020000000-0x6031ffffff 64bit pref]
> [ 598.847319] pci 0000:2b:00.0: PCI bridge to [bus 2c-53]
> [ 598.847789] pci 0000:2b:00.0: bridge window [mem 0x6e000000-0x7a0fffff]
> [ 598.848255] pci 0000:2b:00.0: bridge window [mem
> 0x6020000000-0x6031ffffff 64bit pref]
> [ 598.848720] pcieport 0000:00:07.1: PCI bridge to [bus 2b-53]
> [ 598.849198] pcieport 0000:00:07.1: bridge window [mem
> 0x6e000000-0x7a1fffff]
> [ 598.849667] pcieport 0000:00:07.1: bridge window [mem
> 0x6020000000-0x603bffffff 64bit pref]
> [ 598.850136] PCI: No. 2 try to assign unassigned res
> [ 598.850602] pci 0000:2c:00.0: disabling bridge window [mem
> 0x00000000-0x000fffff 64bit pref disabled] to [bus 2d] (unused)
> [ 598.851083] pci 0000:2c:00.0: disabling bridge window [mem
> 0x00000000-0x000fffff disabled] to [bus 2d] (unused)
> [ 598.851556] pci 0000:2c:01.0: bridge window [io size 0xab000] to [bus
> 2e-53] add_size 155000
> [ 598.852035] pci 0000:2b:00.0: bridge window [io size 0x200000] to [bus
> 2c-53] add_size 155000
> [ 598.852530] pcieport 0000:00:07.1: bridge window [io size 0x200000] to
> [bus 2b-53] add_size 155000
> [ 598.853014] pcieport 0000:00:07.1: bridge window [io size 0x355000]:
> can't assign; no space
> [ 598.853493] pcieport 0000:00:07.1: bridge window [io size 0x355000]:
> failed to assign
> [ 598.853971] pcieport 0000:00:07.1: bridge window [io size 0x200000]:
> can't assign; no space
> [ 598.854448] pcieport 0000:00:07.1: bridge window [io size 0x200000]:
> failed to assign
> [ 598.854921] pci 0000:2b:00.0: bridge window [io size 0x355000]: can't
> assign; no space
> [ 598.855401] pci 0000:2b:00.0: bridge window [io size 0x355000]: failed
> to assign
> [ 598.855896] pci 0000:2b:00.0: bridge window [io size 0x200000]: can't
> assign; no space
> [ 598.856376] pci 0000:2b:00.0: bridge window [io size 0x200000]: failed
> to assign
> [ 598.856847] pci 0000:2c:00.0: bridge window [io size 0x1000]: can't
> assign; no space
> [ 598.857319] pci 0000:2c:00.0: bridge window [io size 0x1000]: failed to
> assign
> [ 598.857788] pci 0000:2c:01.0: bridge window [io size 0x11c000]: can't
> assign; no space
> [ 598.858255] pci 0000:2c:01.0: bridge window [io size 0x11c000]: failed
> to assign
> [ 598.858722] pci 0000:2c:00.0: bridge window [io size 0x1000]: can't
> assign; no space
> [ 598.859209] pci 0000:2c:00.0: bridge window [io size 0x1000]: failed to
> assign
> [ 598.859677] pci 0000:2c:01.0: bridge window [io size 0x11c000]: can't
> assign; no space
> [ 598.860143] pci 0000:2c:01.0: bridge window [io size 0x11c000]: failed
> to assign
> [ 598.860609] pci 0000:2c:00.0: PCI bridge to [bus 2d]
> [ 598.861088] pci 0000:2e:00.0: bridge window [io size 0x11c000]: can't
> assign; no space
> [ 598.861556] pci 0000:2e:00.0: bridge window [io size 0x11c000]: failed
> to assign
> [ 598.862018] pci 0000:2e:00.0: bridge window [io size 0x11c000]: can't
> assign; no space
> [ 598.862501] pci 0000:2e:00.0: bridge window [io size 0x11c000]: failed
> to assign
> [ 598.862970] pci 0000:2f:01.0: bridge window [io size 0x11c000]: can't
> assign; no space
> [ 598.863429] pci 0000:2f:01.0: bridge window [io size 0x11c000]: failed
> to assign
> [ 598.863891] pci 0000:2f:01.0: bridge window [io size 0x11c000]: can't
> assign; no space
> [ 598.864349] pci 0000:2f:01.0: bridge window [io size 0x11c000]: failed
> to assign
> [ 598.864802] pci 0000:30:00.0: BAR 5 [io size 0x0080]: can't assign; no
> space
> [ 598.865254] pci 0000:30:00.0: BAR 5 [io size 0x0080]: failed to assign
> [ 598.865715] pci 0000:30:00.0: BAR 5 [io size 0x0080]: can't assign; no
> space
> [ 598.866163] pci 0000:30:00.0: BAR 5 [io size 0x0080]: failed to assign
> [ 598.866615] pci 0000:2f:01.0: PCI bridge to [bus 30]
> [ 598.867073] pci 0000:2f:01.0: bridge window [mem 0x6e000000-0x720fffff]
> [ 598.867528] pci 0000:2f:01.0: bridge window [mem
> 0x6020000000-0x6031ffffff 64bit pref]
> [ 598.867992] pci 0000:2e:00.0: PCI bridge to [bus 2f-30]
> [ 598.868448] pci 0000:2e:00.0: bridge window [mem 0x6e000000-0x720fffff]
> [ 598.868907] pci 0000:2e:00.0: bridge window [mem
> 0x6020000000-0x6031ffffff 64bit pref]
> [ 598.869374] pci 0000:2c:01.0: PCI bridge to [bus 2e-53]
> [ 598.869833] pci 0000:2c:01.0: bridge window [mem 0x6e000000-0x720fffff]
> [ 598.870286] pci 0000:2c:01.0: bridge window [mem
> 0x6020000000-0x6031ffffff 64bit pref]
> [ 598.870749] pci 0000:2b:00.0: PCI bridge to [bus 2c-53]
> [ 598.871209] pci 0000:2b:00.0: bridge window [mem 0x6e000000-0x7a0fffff]
> [ 598.871670] pci 0000:2b:00.0: bridge window [mem
> 0x6020000000-0x6031ffffff 64bit pref]
> [ 598.872132] pcieport 0000:00:07.1: PCI bridge to [bus 2b-53]
> [ 598.872613] pcieport 0000:00:07.1: bridge window [mem
> 0x6e000000-0x7a1fffff]
> [ 598.873080] pcieport 0000:00:07.1: bridge window [mem
> 0x6020000000-0x603bffffff 64bit pref]
> [ 598.873649] pcieport 0000:2b:00.0: enabling device (0000 -> 0002)
> [ 598.874666] pcieport 0000:2c:01.0: enabling device (0000 -> 0002)
> [ 598.875244] pcieport 0000:2c:01.0: pciehp: Slot #1 AttnBtn- PwrCtrl- MRL-
> AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis- LLActRep+
> [ 598.876454] pcieport 0000:2c:02.0: pciehp: Hotplug bridge without
> secondary bus, ignoring
> [ 598.877284] pcieport 0000:2c:03.0: pciehp: Hotplug bridge without
> secondary bus, ignoring
> [ 598.878335] pcieport 0000:2e:00.0: enabling device (0000 -> 0002)
> [ 598.879210] pcieport 0000:2f:01.0: enabling device (0000 -> 0002)
> [ 598.880224] nvidia 0000:30:00.0: enabling device (0000 -> 0002)
> [ 598.880833] nvidia 0000:30:00.0: vgaarb: VGA decodes changed:
> olddecodes=io+mem,decodes=none:owns=none
> [ 599.171370] [drm] [nvidia-drm] [GPU ID 0x00003000] Loading driver
> [ 599.172273] [drm] Initialized nvidia-drm 0.0.0 for 0000:30:00.0 on minor
> 3
> [ 599.172936] pci 0000:30:00.1: extending delay after power-on from D3hot
> to 20 msec
> [ 599.173650] pci 0000:30:00.1: D0 power state depends on 0000:30:00.0
> [ 683.104898] Loading firmware: nvidia/595.71.05/gsp_ga10x.bin
> [ 683.634039] Loading firmware: nvidia/595.71.05/gsp_ga10x.bin
> [ 684.043158] Loading firmware: nvidia/595.71.05/gsp_ga10x.bin
>
> So, only one of the two hub-connected eGPUs are recognized.
>
>
> pciehp: Hotplug bridge without secondary bus, ignoring <- This sounds less
> promising.
>
>
> lspci (after connecting hub):
>
> 00:00.0 Host bridge: Intel Corporation 12th Gen Core Processor Host
> Bridge/DRAM Registers (rev 02)
> 00:02.0 VGA compatible controller: Intel Corporation Alder Lake-P GT2 [Iris
> Xe Graphics] (rev 0c)
> 00:04.0 Signal processing controller: Intel Corporation Alder Lake
> Innovation Platform Framework Processor Participant (rev 02)
> 00:06.0 PCI bridge: Intel Corporation 12th Gen Core Processor PCI Express x4
> Controller #0 (rev 02)
> 00:07.0 PCI bridge: Intel Corporation Alder Lake-P Thunderbolt 4 PCI Express
> Root Port #0 (rev 02)
> 00:07.1 PCI bridge: Intel Corporation Alder Lake-P Thunderbolt 4 PCI Express
> Root Port #1 (rev 02)
> 00:07.2 PCI bridge: Intel Corporation Alder Lake-P Thunderbolt 4 PCI Express
> Root Port #2 (rev 02)
> 00:07.3 PCI bridge: Intel Corporation Alder Lake-P Thunderbolt 4 PCI Express
> Root Port #3 (rev 02)
> 00:08.0 System peripheral: Intel Corporation 12th Gen Core Processor
> Gaussian & Neural Accelerator (rev 02)
> 00:0a.0 Signal processing controller: Intel Corporation Platform Monitoring
> Technology (rev 01)
> 00:0d.0 USB controller: Intel Corporation Alder Lake-P Thunderbolt 4 USB
> Controller (rev 02)
> 00:0d.2 USB controller: Intel Corporation Alder Lake-P Thunderbolt 4 NHI #0
> (rev 02)
> 00:0d.3 USB controller: Intel Corporation Alder Lake-P Thunderbolt 4 NHI #1
> (rev 02)
> 00:14.0 USB controller: Intel Corporation Alder Lake PCH USB 3.2 xHCI Host
> Controller (rev 01)
> 00:14.2 RAM memory: Intel Corporation Alder Lake PCH Shared SRAM (rev 01)
> 00:15.0 Serial bus controller: Intel Corporation Alder Lake PCH Serial IO
> I2C Controller #0 (rev 01)
> 00:15.1 Serial bus controller: Intel Corporation Alder Lake PCH Serial IO
> I2C Controller #1 (rev 01)
> 00:15.3 Serial bus controller: Intel Corporation Alder Lake PCH Serial IO
> I2C Controller #3 (rev 01)
> 00:16.0 Communication controller: Intel Corporation Alder Lake PCH HECI
> Controller (rev 01)
> 00:16.3 Serial controller: Intel Corporation Alder Lake AMT SOL Redirection
> (rev 01)
> 00:1d.0 PCI bridge: Intel Corporation Alder Lake PCI Express Root Port #9
> (rev 01)
> 00:1f.0 ISA bridge: Intel Corporation Alder Lake PCH eSPI Controller (rev
> 01)
> 00:1f.3 Audio device: Intel Corporation Alder Lake PCH-P High Definition
> Audio Controller (rev 01)
> 00:1f.4 SMBus: Intel Corporation Alder Lake PCH-P SMBus Host Controller (rev
> 01)
> 00:1f.5 Serial bus controller: Intel Corporation Alder Lake-P PCH SPI
> Controller (rev 01)
> 01:00.0 Non-Volatile memory controller: Samsung Electronics Co Ltd NVMe SSD
> Controller PM9C1a (DRAM-less)
> 02:00.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C step)
> [Alpine Ridge 2C 2016] (rev 02)
> 03:01.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C step)
> [Alpine Ridge 2C 2016] (rev 02)
> 04:00.0 VGA compatible controller: NVIDIA Corporation GA102 [GeForce RTX
> 3090] (rev a1)
> 04:00.1 Audio device: NVIDIA Corporation GA102 High Definition Audio
> Controller (rev a1)
> 2b:00.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
> 2020] (rev 03)
> 2c:00.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
> 2020] (rev 03)
> 2c:01.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
> 2020] (rev 03)
> 2c:02.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
> 2020] (rev 03)
> 2c:03.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
> 2020] (rev 03)
> 2c:04.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
> 2020] (rev 03)
> 2e:00.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C step)
> [Alpine Ridge 2C 2016] (rev 02)
> 2f:01.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C step)
> [Alpine Ridge 2C 2016] (rev 02)
> 30:00.0 VGA compatible controller: NVIDIA Corporation GA102 [GeForce RTX
> 3090] (rev a1)
> 30:00.1 Audio device: NVIDIA Corporation GA102 High Definition Audio
> Controller (rev a1)
> 7d:00.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C step)
> [Alpine Ridge 2C 2016] (rev 02)
> 7e:01.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C step)
> [Alpine Ridge 2C 2016] (rev 02)
> 7f:00.0 VGA compatible controller: NVIDIA Corporation GA102 [GeForce RTX
> 3090 Ti] (rev a1)
> 7f:00.1 Audio device: NVIDIA Corporation GA102 High Definition Audio
> Controller (rev a1)
> a6:00.0 Ethernet controller: Intel Corporation Ethernet Controller I226-V
> (rev 04)
>
>
> /proc/iomem after connecting hub
>
> 00000000-00000fff : Reserved
> 00001000-0009efff : System RAM
> 0009f000-000fffff : Reserved
> 000a0000-000bffff : PCI Bus 0000:00
> 000f0000-000fffff : System ROM
> 00100000-3727bfff : System RAM
> 3727c000-372cafff : Reserved
> 372cb000-388b2fff : System RAM
> 388b3000-388b3fff : Reserved
> 388b4000-3b138fff : System RAM
> 3b139000-3ba38fff : Reserved
> 3ba39000-3d84efff : System RAM
> 3d84f000-40a7efff : Reserved
> 40a7f000-43a2efff : ACPI Non-volatile Storage
> 43945000-43945fff : USBC000:00
> 43a2f000-43afefff : ACPI Tables
> 43aff000-43afffff : System RAM
> 43b00000-47ffffff : Reserved
> 49200000-493fffff : Reserved
> 4a000000-503fffff : Reserved
> 4c800000-503fffff : Graphics Stolen Memory
> 50400000-bfffffff : PCI Bus 0000:00
> 50400000-50400fff : 0000:00:1f.5
> 50500000-507fffff : PCI Bus 0000:a6
> 50500000-505fffff : 0000:a6:00.0
> 50500000-505fffff : igc
> 50600000-506fffff : 0000:a6:00.0
> 50700000-50703fff : 0000:a6:00.0
> 50700000-50703fff : igc
> 52000000-5e1fffff : PCI Bus 0000:7d
> 52000000-5e0fffff : PCI Bus 0000:7e
> 52000000-5e0fffff : PCI Bus 0000:7f
> 52000000-52ffffff : 0000:7f:00.0
> 52000000-52ffffff : nvidia
> 53000000-5307ffff : 0000:7f:00.0
> 53080000-53083fff : 0000:7f:00.1
> 60000000-6c1fffff : PCI Bus 0000:54
> 6e000000-7a1fffff : PCI Bus 0000:2b
> 6e000000-7a0fffff : PCI Bus 0000:2c
> 6e000000-720fffff : PCI Bus 0000:2e
> 6e000000-720fffff : PCI Bus 0000:2f
> 6e000000-720fffff : PCI Bus 0000:30
> 6e000000-6effffff : 0000:30:00.0
> 6e000000-6effffff : nvidia
> 6f000000-6f07ffff : 0000:30:00.0
> 6f080000-6f083fff : 0000:30:00.1
> 7a400000-7a4fffff : PCI Bus 0000:01
> 7a400000-7a403fff : 0000:01:00.0
> 7a400000-7a403fff : nvme
> 7a600000-7a60ffff : 0000:00:14.0
> 7a600000-7a60ffff : xhci-hcd
> 7a611000-7a611fff : 0000:00:16.3
> 7c000000-881fffff : PCI Bus 0000:02
> 7c000000-880fffff : PCI Bus 0000:03
> 7c000000-880fffff : PCI Bus 0000:04
> 7c000000-7cffffff : 0000:04:00.0
> 7c000000-7cffffff : nvidia
> 7d000000-7d07ffff : 0000:04:00.0
> 7d080000-7d083fff : 0000:04:00.1
> c0000000-cfffffff : PCI ECAM 0000 [bus 00-ff]
> c0000000-cfffffff : PNP0C02:01
> fd000000-fd68ffff : PNP0C02:02
> fd690000-fd69ffff : INTC1055:00
> fd6a0000-fd6affff : INTC1055:00
> fd6b0000-fd6cffff : PNP0C02:02
> fd6d0000-fd6dffff : INTC1055:00
> fd6e0000-fd6effff : INTC1055:00
> fd6f0000-fdffffff : PNP0C02:02
> fe000000-fe01ffff : PNP0C02:02
> fe04c000-fe04ffff : PNP0C02:02
> fe050000-fe0affff : PNP0C02:02
> fe0d0000-fe0fffff : PNP0C02:02
> fe200000-fe7fffff : PNP0C02:02
> fec00000-fec003ff : IOAPIC 0
> fed00000-fed003ff : HPET 0
> fed00000-fed003ff : PNP0103:00
> fed20000-fed7ffff : Reserved
> fed40000-fed44fff : NTC0702:00
> fed90000-fed90fff : dmar0
> fed91000-fed91fff : dmar1
> feda0000-feda0fff : PNP0C02:01
> feda1000-feda1fff : PNP0C02:01
> fedc0000-fedc7fff : PNP0C02:01
> fee00000-feefffff : PNP0C02:01
> ff000000-ffffffff : PNP0C02:02
> 100000000-10afbfffff : System RAM
> d6a000000-d6b1e52f7 : Kernel code
> d6b200000-d6b7a0fff : Kernel rodata
> d6b800000-d6bac0cff : Kernel data
> d6c247000-d6c30ffff : Kernel bss
> 10afc00000-10afffffff : RAM buffer
> 4000000000-7fffffffff : PCI Bus 0000:00
> 4000000000-400fffffff : 0000:00:02.0
> 4010000000-4016ffffff : 0000:00:02.0
> 4017000000-4017000fff : 0000:00:15.0
> 4017000000-40170001ff : lpss_dev
> 4017000000-40170001ff : i2c_designware.0 lpss_dev
> 4017000200-40170002ff : lpss_priv
> 4017000800-4017000fff : idma64.0
> 4017001000-4017001fff : 0000:00:15.1
> 4017001000-40170011ff : lpss_dev
> 4017001000-40170011ff : i2c_designware.1 lpss_dev
> 4017001200-40170012ff : lpss_priv
> 4017001800-4017001fff : idma64.1
> 4017002000-4017002fff : 0000:00:15.3
> 4017002000-40170021ff : lpss_dev
> 4017002000-40170021ff : i2c_designware.2 lpss_dev
> 4017002200-40170022ff : lpss_priv
> 4017002800-4017002fff : idma64.2
> 4020000000-40ffffffff : 0000:00:02.0
> 6000000000-601bffffff : PCI Bus 0000:02
> 6000000000-6011ffffff : PCI Bus 0000:03
> 6000000000-6011ffffff : PCI Bus 0000:04
> 6000000000-600fffffff : 0000:04:00.0
> 6010000000-6011ffffff : 0000:04:00.0
> 6020000000-603bffffff : PCI Bus 0000:2b
> 6020000000-6031ffffff : PCI Bus 0000:2c
> 6020000000-6031ffffff : PCI Bus 0000:2e
> 6020000000-6031ffffff : PCI Bus 0000:2f
> 6020000000-6031ffffff : PCI Bus 0000:30
> 6020000000-602fffffff : 0000:30:00.0
> 6030000000-6031ffffff : 0000:30:00.0
> 6040000000-605bffffff : PCI Bus 0000:54
> 605c000000-605cffffff : 0000:00:02.0
> 605d000000-605d0fffff : 0000:00:1f.3
> 605d100000-605d13ffff : 0000:00:0d.3
> 605d100000-605d13ffff : thunderbolt
> 605d140000-605d17ffff : 0000:00:0d.2
> 605d140000-605d17ffff : thunderbolt
> 605d180000-605d19ffff : 0000:00:04.0
> 605d180000-605d19ffff : proc_thermal
> 605d1a0000-605d1affff : 0000:00:0d.0
> 605d1a0000-605d1affff : xhci-hcd
> 605d1b0000-605d1b7fff : 0000:00:0a.0
> 605d1b8000-605d1bbfff : 0000:00:1f.3
> 605d1bc000-605d1bffff : 0000:00:14.2
> 605d1c0000-605d1c00ff : 0000:00:1f.4
> 605d1c0000-605d1c00ff : i801_smbus
> 605d1c1000-605d1c1fff : 0000:00:16.0
> 605d1c1000-605d1c1fff : mei_me
> 605d1c5000-605d1c5fff : 0000:00:14.2
> 605d1c6000-605d1c6fff : 0000:00:0d.3
> 605d1c7000-605d1c7fff : 0000:00:0d.2
> 605d1c8000-605d1c8fff : 0000:00:08.0
> 6060000000-607bffffff : PCI Bus 0000:7d
> 6060000000-6071ffffff : PCI Bus 0000:7e
> 6060000000-6071ffffff : PCI Bus 0000:7f
> 6060000000-606fffffff : 0000:7f:00.0
> 6070000000-6071ffffff : 0000:7f:00.0
>
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Connecting multiple TB3 eGPUs via USB4 hub?'
2026-06-08 15:26 ` Connecting multiple TB3 eGPUs via USB4 hub?' Bjorn Helgaas
@ 2026-06-09 12:08 ` Mika Westerberg
2026-06-10 22:48 ` Dag B
0 siblings, 1 reply; 6+ messages in thread
From: Mika Westerberg @ 2026-06-09 12:08 UTC (permalink / raw)
To: Bjorn Helgaas
Cc: Dag B, linux-pci, linux-usb, Ilpo Järvinen, Lukas Wunner
Hi,
On Mon, Jun 08, 2026 at 10:26:40AM -0500, Bjorn Helgaas wrote:
> [+cc linux-usb (Thunderbolt maintainers), Ilpo, Lukas]
>
> On Sun, May 24, 2026 at 04:56:56PM +0200, Dag B wrote:
> > I am attempting to connect two TB3 enclosures to the same USB4 port via a
> > USB4 hub.
> >
> > I cannot figure out of this is in violation of the TB3, TB4 or USB4 spec.
>
> I'm not aware of a spec issue here.
It should be fine but typically PCIe resources for one tunneled PCIe root
port may not be enough for multiple GPUs. Therefore I suggest to connect
them directly to the host USB4 ports without a hub.
Second thing is that you have bunch of PCIe related command line parameters
that may affect. I suggest removing all of them, and retry. There is hardly
any reason to add these - the kernel should be able to handle this by
default.
Then provide full dmesg along with output of 'sudo lspci -vv' so we can
look a the resource allocation.
> Below it looks like you hot-added the hub. Does it make any
> difference if everything is connected before boot?
>
> Please don't filter the dmesg logs you collect. We can do that if
> needed.
>
> > .... or, in case it is not:
> >
> > Can this work with current USB4/Thunderbolt drivers in Linux? (I am not
> > worried about bandwidth limitations.)
> >
> >
> > This appears to be too niche to find answers anywhere else. I would be very
> > grateful for any clarifying answer here, really.
> >
> >
> > Hardware
> >
> > - Framework 13 mb with 12th gen Alder Lake (Intel Corporation Alder Lake-P
> > Thunderbolt 4 NHI) (4 USB4 ports)
> >
> > - Sonnettech Echo 5 hub (Intel Corporation Thunderbolt 4 Bridge [Goshen
> > Ridge 2020] )
> >
> > - Razer Core X (Intel Corporation JHL6340 Thunderbolt 3 Bridge (C step)
> > [Alpine Ridge 2C 2016])
> >
> > - GPUs are Nvidia RTX 3090. They expose two PCIe devices, the GPU and an
> > audio device.
> >
> >
> > Using kernel 7.0.10 with gentoo patches.
> >
> >
> > Been playing *a lot* with various permutations of pci-related kernel
> > options. Current options:
> >
> > pci=realloc=on,hpmmiosize=256M,hpiosize=2M,hpmemsize=1G,hpbussize=0x33,pcie_scan_all,big_root_window
> >
> >
> > pcie_port_pm=off
> >
> > pcie_aspm.policy=performance
> >
> > thunderbolt.clx=0
> >
> >
> >
> > Booting with 2 eGPUS directly connected to separate USB4 ports. (pcie
> > messages only):
> >
> > [ 0.000000] Command line: root=/dev/nvme0n1p2 pci=realloc=on,hpmmiosize=256M,hpiosize=2M,hpmemsize=1G,hpbussize=0x33,pcie_scan_all,big_root_window
> > pcie_port_pm=off pcie_aspm.policy=performance thunderbolt.clx=0
> > [ 0.082296] Kernel command line: pci=realloc=on,hpmmiosize=256M,hpiosize=2M,hpmemsize=1G,hpbussize=0x33,pcie_scan_all,big_root_window
> > \
> > [ 0.082297] Kernel command line: pcie_port_pm=off
> > pcie_aspm.policy=performance \
> > [ 0.864174] pcieport 0000:00:06.0: PME: Signaling with IRQ 122
> > [ 0.864343] pcieport 0000:00:07.0: PME: Signaling with IRQ 123
> > [ 0.864358] pcieport 0000:00:07.0: pciehp: Slot #3 AttnBtn- PwrCtrl- MRL-
> > AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis- LLActRep+
> > [ 0.864661] pcieport 0000:00:07.1: PME: Signaling with IRQ 124
> > [ 0.864677] pcieport 0000:00:07.1: pciehp: Slot #4 AttnBtn- PwrCtrl- MRL-
> > AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis- LLActRep+
> > [ 0.864900] pcieport 0000:00:07.2: PME: Signaling with IRQ 125
> > [ 0.864914] pcieport 0000:00:07.2: pciehp: Slot #5 AttnBtn- PwrCtrl- MRL-
> > AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis- LLActRep+
> > [ 0.865139] pcieport 0000:00:07.3: PME: Signaling with IRQ 126
> > [ 0.865153] pcieport 0000:00:07.3: pciehp: Slot #6 AttnBtn- PwrCtrl- MRL-
> > AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis- LLActRep+
> > [ 0.865376] pcieport 0000:00:1d.0: PME: Signaling with IRQ 127
> > [ 5.127515] pcieport 0000:00:07.3: pciehp: Slot(6): Card present
> > [ 5.134225] pcieport 0000:00:07.0: pciehp: Slot(3): Card present
> > [ 5.263158] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
> > can't assign; no space
> > [ 5.263178] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
> > failed to assign
> > [ 5.263197] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
> > can't assign; no space
> > [ 5.263215] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
> > failed to assign
> > [ 5.270527] pcieport 0000:00:07.3: PCI bridge to [bus 7d-a5]
> > [ 5.270529] pcieport 0000:00:07.3: bridge window [mem
> > 0x52000000-0x5e1fffff]
> > [ 5.270531] pcieport 0000:00:07.3: bridge window [mem
> > 0x6060000000-0x607bffffff 64bit pref]
> > [ 5.270537] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
> > can't assign; no space
> > [ 5.270537] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
> > failed to assign
> > [ 5.270538] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
> > can't assign; no space
> > [ 5.270539] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
> > failed to assign
> > [ 5.270577] pcieport 0000:00:07.3: PCI bridge to [bus 7d-a5]
> > [ 5.270579] pcieport 0000:00:07.3: bridge window [mem
> > 0x52000000-0x5e1fffff]
> > [ 5.270581] pcieport 0000:00:07.3: bridge window [mem
> > 0x6060000000-0x607bffffff 64bit pref]
> > [ 5.270703] pcieport 0000:7d:00.0: enabling device (0000 -> 0002)
> > [ 5.287127] pcieport 0000:7e:01.0: enabling device (0000 -> 0002)
> > [ 5.325065] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
> > can't assign; no space
> > [ 5.325560] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
> > failed to assign
> > [ 5.326061] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
> > can't assign; no space
> > [ 5.326560] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
> > failed to assign
> > [ 5.340678] pcieport 0000:00:07.0: PCI bridge to [bus 02-2a]
> > [ 5.340680] pcieport 0000:00:07.0: bridge window [mem
> > 0x7c000000-0x881fffff]
> > [ 5.340682] pcieport 0000:00:07.0: bridge window [mem
> > 0x6000000000-0x601bffffff 64bit pref]
> > [ 5.340688] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
> > can't assign; no space
> > [ 5.340689] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
> > failed to assign
> > [ 5.340690] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
> > can't assign; no space
> > [ 5.340690] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
> > failed to assign
> > [ 5.340741] pcieport 0000:00:07.0: PCI bridge to [bus 02-2a]
> > [ 5.340744] pcieport 0000:00:07.0: bridge window [mem
> > 0x7c000000-0x881fffff]
> > [ 5.340745] pcieport 0000:00:07.0: bridge window [mem
> > 0x6000000000-0x601bffffff 64bit pref]
> > [ 5.340866] pcieport 0000:02:00.0: enabling device (0000 -> 0002)
> > [ 5.355410] pcieport 0000:03:01.0: enabling device (0000 -> 0002)
> >
> >
> > Then, connecting the hub with two additional eGPUs to a third USB4 port (all
> > messages):
> >
> > [ 596.449718] thunderbolt 0-3: new device found, vendor=0x8 device=0x5f
> > [ 596.449771] thunderbolt 0-3: Sonnet Technologies, Inc. Echo 5 Thunderbolt
> > 4 Hub
> > [ 596.710380] thunderbolt 0-0:3.1: new retimer found, vendor=0x8087
> > device=0x15ee
> > [ 596.962295] usb 3-3: new high-speed USB device number 4 using xhci_hcd
> > [ 597.156102] usb 3-3: New USB device found, idVendor=1d5c, idProduct=5801,
> > bcdDevice= 1.01
> > [ 597.156118] usb 3-3: New USB device strings: Mfr=1, Product=2,
> > SerialNumber=0
> > [ 597.156130] usb 3-3: Product: USB2.0 Hub
> > [ 597.156138] usb 3-3: Manufacturer: Fresco Logic, Inc.
> > [ 597.157120] hub 3-3:1.0: USB hub found
> > [ 597.157152] hub 3-3:1.0: 6 ports detected
> > [ 597.458933] usb 2-2: new SuperSpeed Plus Gen 2x1 USB device number 4
> > using xhci_hcd
> > [ 597.472670] usb 2-2: New USB device found, idVendor=8087, idProduct=0b40,
> > bcdDevice=12.34
> > [ 597.472687] usb 2-2: New USB device strings: Mfr=1, Product=2,
> > SerialNumber=0
> > [ 597.472700] usb 2-2: Product: USB3.0 Hub
> > [ 597.472711] usb 2-2: Manufacturer: Intel Corporation.
> > [ 597.473459] hub 2-2:1.0: USB hub found
> > [ 597.473587] hub 2-2:1.0: 4 ports detected
> > [ 597.559335] thunderbolt 0-303: new device found, vendor=0x127 device=0x1
> > [ 597.559350] thunderbolt 0-303: Razer Core X
> > [ 597.702310] usb 3-3.5: new full-speed USB device number 5 using xhci_hcd
> > [ 597.801389] usb 3-3.5: New USB device found, idVendor=2a8c,
> > idProduct=205f, bcdDevice=17.46
> > [ 597.801406] usb 3-3.5: New USB device strings: Mfr=1, Product=2,
> > SerialNumber=3
> > [ 597.801418] usb 3-3.5: Product: Echo 5 Thunderbolt 4 Hub
> > [ 597.801428] usb 3-3.5: Manufacturer: Sonnet Technologies,Inc.
> > [ 597.801438] usb 3-3.5: SerialNumber: 11AD1D0A510D2E0D381E0B00
> > [ 597.885632] usb 3-3.6: new high-speed USB device number 6 using xhci_hcd
> > [ 597.983768] usb 3-3.6: New USB device found, idVendor=1d5c,
> > idProduct=5530, bcdDevice= 1.01
> > [ 597.983785] usb 3-3.6: New USB device strings: Mfr=1, Product=2,
> > SerialNumber=0
> > [ 597.983798] usb 3-3.6: Product: Frescologic VENDOR HID
> > [ 597.983807] usb 3-3.6: Manufacturer: Frescologic
> > [ 597.985769] hid-generic 0003:1D5C:5530.0002: hidraw1: USB HID v1.01
> > Device [Frescologic Frescologic VENDOR HID] on usb-0000:00:14.0-3.6/input0
> > [ 598.294042] thunderbolt 0-503: new device found, vendor=0x127 device=0x1
> > [ 598.294057] thunderbolt 0-503: Razer Core X
> > [ 598.619985] pcieport 0000:00:07.1: pciehp: Slot(4): Card present
> > [ 598.619999] pcieport 0000:00:07.1: pciehp: Slot(4): Link Up
> > [ 598.745860] pci 0000:2b:00.0: [8086:0b26] type 01 class 0x060400 PCIe
> > Switch Upstream Port
> > [ 598.745987] pci 0000:2b:00.0: PCI bridge to [bus 00]
> > [ 598.746028] pci 0000:2b:00.0: bridge window [io 0x0000-0x0fff]
> > [ 598.746061] pci 0000:2b:00.0: bridge window [mem 0x00000000-0x000fffff]
> > [ 598.746113] pci 0000:2b:00.0: bridge window [mem 0x00000000-0x000fffff
> > 64bit pref]
> > [ 598.746173] pci 0000:2b:00.0: enabling Extended Tags
> > [ 598.746450] pci 0000:2b:00.0: supports D1 D2
> > [ 598.746471] pci 0000:2b:00.0: PME# supported from D0 D1 D2 D3hot D3cold
> > [ 598.747002] pci 0000:2b:00.0: Adding to iommu group 22
> > [ 598.755705] pci 0000:2b:00.0: bridge configuration invalid ([bus 00-00]),
> > reconfiguring
> > [ 598.755945] pci 0000:2c:00.0: [8086:0b26] type 01 class 0x060400 PCIe
> > Switch Downstream Port
> > [ 598.756014] pci 0000:2c:00.0: PCI bridge to [bus 00]
> > [ 598.756039] pci 0000:2c:00.0: bridge window [io 0x0000-0x0fff]
> > [ 598.756059] pci 0000:2c:00.0: bridge window [mem 0x00000000-0x000fffff]
> > [ 598.756094] pci 0000:2c:00.0: bridge window [mem 0x00000000-0x000fffff
> > 64bit pref]
> > [ 598.756136] pci 0000:2c:00.0: enabling Extended Tags
> > [ 598.756346] pci 0000:2c:00.0: supports D1 D2
> > [ 598.756359] pci 0000:2c:00.0: PME# supported from D0 D1 D2 D3hot D3cold
> > [ 598.756675] pci 0000:2c:00.0: Adding to iommu group 23
> > [ 598.756854] pci 0000:2c:01.0: [8086:0b26] type 01 class 0x060400 PCIe
> > Switch Downstream Port
> > [ 598.756925] pci 0000:2c:01.0: PCI bridge to [bus 00]
> > [ 598.756950] pci 0000:2c:01.0: bridge window [io 0x0000-0x0fff]
> > [ 598.756970] pci 0000:2c:01.0: bridge window [mem 0x00000000-0x000fffff]
> > [ 598.757863] pci 0000:2c:01.0: bridge window [mem 0x00000000-0x000fffff
> > 64bit pref]
> > [ 598.758743] pci 0000:2c:01.0: enabling Extended Tags
> > [ 598.759822] pci 0000:2c:01.0: supports D1 D2
> > [ 598.760599] pci 0000:2c:01.0: PME# supported from D0 D1 D2 D3hot D3cold
> > [ 598.761582] pci 0000:2c:01.0: Adding to iommu group 24
> > [ 598.762477] pci 0000:2c:02.0: [8086:0b26] type 01 class 0x060400 PCIe
> > Switch Downstream Port
> > [ 598.763270] pci 0000:2c:02.0: PCI bridge to [bus 00]
> > [ 598.764010] pci 0000:2c:02.0: bridge window [io 0x0000-0x0fff]
> > [ 598.764697] pci 0000:2c:02.0: bridge window [mem 0x00000000-0x000fffff]
> > [ 598.765266] pci 0000:2c:02.0: bridge window [mem 0x00000000-0x000fffff
> > 64bit pref]
> > [ 598.765832] pci 0000:2c:02.0: enabling Extended Tags
> > [ 598.766513] pci 0000:2c:02.0: supports D1 D2
> > [ 598.767016] pci 0000:2c:02.0: PME# supported from D0 D1 D2 D3hot D3cold
> > [ 598.767686] pci 0000:2c:02.0: Adding to iommu group 25
> > [ 598.768272] pci 0000:2c:03.0: [8086:0b26] type 01 class 0x060400 PCIe
> > Switch Downstream Port
> > [ 598.768804] pci 0000:2c:03.0: PCI bridge to [bus 00]
> > [ 598.769323] pci 0000:2c:03.0: bridge window [io 0x0000-0x0fff]
> > [ 598.769815] pci 0000:2c:03.0: bridge window [mem 0x00000000-0x000fffff]
> > [ 598.770317] pci 0000:2c:03.0: bridge window [mem 0x00000000-0x000fffff
> > 64bit pref]
> > [ 598.770816] pci 0000:2c:03.0: enabling Extended Tags
> > [ 598.771451] pci 0000:2c:03.0: supports D1 D2
> > [ 598.771929] pci 0000:2c:03.0: PME# supported from D0 D1 D2 D3hot D3cold
> > [ 598.772596] pci 0000:2c:03.0: Adding to iommu group 26
> > [ 598.773173] pci 0000:2c:04.0: [8086:0b26] type 01 class 0x060400 PCIe
> > Switch Downstream Port
> > [ 598.773694] pci 0000:2c:04.0: PCI bridge to [bus 00]
> > [ 598.774196] pci 0000:2c:04.0: bridge window [io 0x0000-0x0fff]
> > [ 598.774683] pci 0000:2c:04.0: bridge window [mem 0x00000000-0x000fffff]
> > [ 598.775179] pci 0000:2c:04.0: bridge window [mem 0x00000000-0x000fffff
> > 64bit pref]
> > [ 598.775687] pci 0000:2c:04.0: enabling Extended Tags
> > [ 598.776319] pci 0000:2c:04.0: supports D1 D2
> > [ 598.776794] pci 0000:2c:04.0: PME# supported from D0 D1 D2 D3hot D3cold
> > [ 598.777437] pci 0000:2c:04.0: Adding to iommu group 27
> > [ 598.777985] pci 0000:2b:00.0: PCI bridge to [bus 2c-53]
> > [ 598.778481] pci 0000:2c:00.0: bridge configuration invalid ([bus 00-00]),
> > reconfiguring
> > [ 598.778983] pci 0000:2c:01.0: bridge configuration invalid ([bus 00-00]),
> > reconfiguring
> > [ 598.779463] pci 0000:2c:02.0: bridge configuration invalid ([bus 00-00]),
> > reconfiguring
> > [ 598.779939] pci 0000:2c:03.0: bridge configuration invalid ([bus 00-00]),
> > reconfiguring
> > [ 598.780408] pci 0000:2c:04.0: bridge configuration invalid ([bus 00-00]),
> > reconfiguring
> > [ 598.780987] pci 0000:2c:00.0: PCI bridge to [bus 2d-53]
> > [ 598.781458] pci_bus 0000:2d: busn_res: [bus 2d-53] end is updated to 2d
> > [ 598.782096] pci 0000:2e:00.0: [8086:15da] type 01 class 0x060400 PCIe
> > Switch Upstream Port
> > [ 598.782628] pci 0000:2e:00.0: PCI bridge to [bus 00]
> > [ 598.783089] pci 0000:2e:00.0: bridge window [io 0x0000-0x0fff]
> > [ 598.783548] pci 0000:2e:00.0: bridge window [mem 0x00000000-0x000fffff]
> > [ 598.784020] pci 0000:2e:00.0: bridge window [mem 0x00000000-0x000fffff
> > 64bit pref]
> > [ 598.784493] pci 0000:2e:00.0: enabling Extended Tags
> > [ 598.785172] pci 0000:2e:00.0: supports D1 D2
> > [ 598.785624] pci 0000:2e:00.0: PME# supported from D0 D1 D2 D3hot D3cold
> > [ 598.786319] pci 0000:2e:00.0: Adding to iommu group 28
> > [ 598.792407] pci 0000:2c:01.0: PCI bridge to [bus 2e-53]
> > [ 598.792880] pci 0000:2e:00.0: bridge configuration invalid ([bus 00-00]),
> > reconfiguring
> > [ 598.793579] pci 0000:2f:01.0: [8086:15da] type 01 class 0x060400 PCIe
> > Switch Downstream Port
> > [ 598.794094] pci 0000:2f:01.0: PCI bridge to [bus 00]
> > [ 598.794559] pci 0000:2f:01.0: bridge window [io 0x0000-0x0fff]
> > [ 598.795014] pci 0000:2f:01.0: bridge window [mem 0x00000000-0x000fffff]
> > [ 598.795485] pci 0000:2f:01.0: bridge window [mem 0x00000000-0x000fffff
> > 64bit pref]
> > [ 598.795981] pci 0000:2f:01.0: enabling Extended Tags
> > [ 598.796665] pci 0000:2f:01.0: supports D1 D2
> > [ 598.797111] pci 0000:2f:01.0: PME# supported from D0 D1 D2 D3hot D3cold
> > [ 598.797785] pci 0000:2f:01.0: Adding to iommu group 29
> > [ 598.798344] pci 0000:2e:00.0: PCI bridge to [bus 2f-53]
> > [ 598.798826] pci 0000:2f:01.0: bridge configuration invalid ([bus 00-00]),
> > reconfiguring
> > [ 598.799576] pci 0000:30:00.0: [10de:2204] type 00 class 0x030000 PCIe
> > Legacy Endpoint
> > [ 598.800146] pci 0000:30:00.0: BAR 0 [mem 0x00000000-0x00ffffff]
> > [ 598.800598] pci 0000:30:00.0: BAR 1 [mem 0x00000000-0x0fffffff 64bit
> > pref]
> > [ 598.801062] pci 0000:30:00.0: BAR 3 [mem 0x00000000-0x01ffffff 64bit
> > pref]
> > [ 598.801512] pci 0000:30:00.0: BAR 5 [io 0x0000-0x007f]
> > [ 598.801961] pci 0000:30:00.0: ROM [mem 0x00000000-0x0007ffff pref]
> > [ 598.802697] pci 0000:30:00.0: PME# supported from D0 D3hot
> > [ 598.803421] pci 0000:30:00.0: 8.000 Gb/s available PCIe bandwidth,
> > limited by 2.5 GT/s PCIe x4 link at 0000:00:07.1 (capable of 252.048 Gb/s
> > with 16.0 GT/s PCIe x16 link)
> > [ 598.804053] pci 0000:30:00.0: Adding to iommu group 29
> > [ 598.804517] pci 0000:30:00.0: vgaarb: bridge control possible
> > [ 598.804969] pci 0000:30:00.0: vgaarb: VGA device added:
> > decodes=io+mem,owns=none,locks=none
> > [ 598.805427] i915 0000:00:02.0: vgaarb: VGA decodes changed:
> > olddecodes=none,decodes=none:owns=io+mem
> > [ 598.806033] pci 0000:30:00.1: [10de:1aef] type 00 class 0x040300 PCIe
> > Endpoint
> > [ 598.806622] pci 0000:30:00.1: BAR 0 [mem 0x00000000-0x00003fff]
> > [ 598.807434] pci 0000:30:00.1: Adding to iommu group 29
> > [ 598.808118] pci 0000:2f:01.0: PCI bridge to [bus 30-53]
> > [ 598.808614] pci_bus 0000:30: busn_res: [bus 30-53] end is updated to 30
> > [ 598.809107] pci_bus 0000:2f: busn_res: [bus 2f-53] end is updated to 30
> > [ 598.809575] pci_bus 0000:2e: busn_res: [bus 2e-53] end is updated to 53
> > [ 598.810077] pci_bus 0000:54: busn_res: [bus 54-7c] end is updated to 7c
> > [ 598.810714] pci_bus 0000:7d: busn_res: [bus 7d-a5] end is updated to a5
> > [ 598.811226] pci_bus 0000:a6: busn_res: [bus a6] end is updated to a6
> > [ 598.811682] pci_bus 0000:2c: busn_res: [bus 2c-53] end can not be updated
> > to a6
> > [ 598.812141] pci 0000:2c:00.0: disabling bridge window [mem
> > 0x00000000-0x000fffff 64bit pref] to [bus 2d] (unused)
> > [ 598.812621] pci 0000:2c:00.0: disabling bridge window [mem
> > 0x00000000-0x000fffff] to [bus 2d] (unused)
> > [ 598.813082] pci 0000:2c:01.0: bridge window [io 0x1000-0x1fff] to [bus
> > 2e-53] add_size 1ff000
> > [ 598.813544] pci 0000:2c:01.0: bridge window [mem 0x10000000-0x21ffffff
> > 64bit pref] to [bus 2e-53] add_size 2e000000 add_align 10000000
> > [ 598.814007] pci 0000:2c:01.0: bridge window [mem 0x01000000-0x020fffff]
> > to [bus 2e-53] add_size 3ef00000 add_align 1000000
> > [ 598.814474] pci 0000:2b:00.0: bridge window [io 0x1000-0x2fff] to [bus
> > 2c-53] add_size 1ff000
> > [ 598.814942] pci 0000:2b:00.0: bridge window [mem 0x10000000-0x21ffffff
> > 64bit pref] to [bus 2c-53] add_size 2e000000 add_align 10000000
> > [ 598.815414] pci 0000:2b:00.0: bridge window [mem 0x01000000-0x020fffff]
> > to [bus 2c-53] add_size 3ef00000 add_align 1000000
> > [ 598.815908] pcieport 0000:00:07.1: bridge window [io size 0x200000] to
> > [bus 2b-53] add_size 1ff000
> > [ 598.816393] pcieport 0000:00:07.1: bridge window [io size 0x3ff000]:
> > can't assign; no space
> > [ 598.816870] pcieport 0000:00:07.1: bridge window [io size 0x3ff000]:
> > failed to assign
> > [ 598.817346] pcieport 0000:00:07.1: bridge window [io size 0x200000]:
> > can't assign; no space
> > [ 598.817828] pcieport 0000:00:07.1: bridge window [io size 0x200000]:
> > failed to assign
> > [ 598.818304] pci 0000:2b:00.0: bridge window [mem size 0x40000000 64bit
> > pref]: can't assign; no space
> > [ 598.818785] pci 0000:2b:00.0: bridge window [mem size 0x40000000 64bit
> > pref]: failed to assign
> > [ 598.819281] pci 0000:2b:00.0: bridge window [mem 0x6e000000-0x7a0fffff]:
> > assigned
> > [ 598.819765] pci 0000:2b:00.0: bridge window [io size 0x200000]: can't
> > assign; no space
> > [ 598.820250] pci 0000:2b:00.0: bridge window [io size 0x200000]: failed
> > to assign
> > [ 598.820740] pci 0000:2b:00.0: bridge window [mem 0x6e000000-0x7a0fffff]:
> > releasing
> > [ 598.821235] pci 0000:2b:00.0: bridge window [mem
> > 0x6020000000-0x6031ffffff 64bit pref]: assigned
> > [ 598.821727] pci 0000:2b:00.0: bridge window [mem 0x6e000000-0x7a0fffff]:
> > assigned
> > [ 598.822227] pci 0000:2b:00.0: bridge window [io size 0x200000]: can't
> > assign; no space
> > [ 598.822722] pci 0000:2b:00.0: bridge window [io size 0x200000]: failed
> > to assign
> > [ 598.823206] pci 0000:2b:00.0: bridge window [mem
> > 0x6020000000-0x6031ffffff 64bit pref]: failed to expand by 0x2e000000
> > [ 598.823697] pci 0000:2b:00.0: bridge window [mem
> > 0x6020000000-0x6031ffffff 64bit pref]: failed to add optional 2e000000
> > [ 598.824186] pci 0000:2c:01.0: bridge window [mem size 0x40000000 64bit
> > pref]: can't assign; no space
> > [ 598.824679] pci 0000:2c:01.0: bridge window [mem size 0x40000000 64bit
> > pref]: failed to assign
> > [ 598.825173] pci 0000:2c:01.0: bridge window [mem 0x6e000000-0x720fffff]:
> > assigned
> > [ 598.825677] pci 0000:2c:00.0: bridge window [io size 0x1000]: can't
> > assign; no space
> > [ 598.826173] pci 0000:2c:00.0: bridge window [io size 0x1000]: failed to
> > assign
> > [ 598.826666] pci 0000:2c:01.0: bridge window [io size 0xab000]: can't
> > assign; no space
> > [ 598.827161] pci 0000:2c:01.0: bridge window [io size 0xab000]: failed to
> > assign
> > [ 598.827652] pci 0000:2c:01.0: bridge window [mem 0x6e000000-0x720fffff]:
> > releasing
> > [ 598.828140] pci 0000:2c:01.0: bridge window [mem
> > 0x6020000000-0x6031ffffff 64bit pref]: assigned
> > [ 598.828630] pci 0000:2c:01.0: bridge window [mem 0x6e000000-0x720fffff]:
> > assigned
> > [ 598.829132] pci 0000:2c:00.0: bridge window [io size 0x1000]: can't
> > assign; no space
> > [ 598.829623] pci 0000:2c:00.0: bridge window [io size 0x1000]: failed to
> > assign
> > [ 598.830116] pci 0000:2c:01.0: bridge window [io size 0xab000]: can't
> > assign; no space
> > [ 598.830606] pci 0000:2c:01.0: bridge window [io size 0xab000]: failed to
> > assign
> > [ 598.831099] pci 0000:2c:01.0: bridge window [mem
> > 0x6020000000-0x6031ffffff 64bit pref]: failed to expand by 0x2e000000
> > [ 598.831588] pci 0000:2c:01.0: bridge window [mem
> > 0x6020000000-0x6031ffffff 64bit pref]: failed to add optional 2e000000
> > [ 598.832080] pci 0000:2c:00.0: PCI bridge to [bus 2d]
> > [ 598.832605] pci 0000:2e:00.0: bridge window [mem
> > 0x6020000000-0x6031ffffff 64bit pref]: assigned
> > [ 598.833106] pci 0000:2e:00.0: bridge window [mem 0x6e000000-0x720fffff]:
> > assigned
> > [ 598.833599] pci 0000:2e:00.0: bridge window [io size 0xab000]: can't
> > assign; no space
> > [ 598.834091] pci 0000:2e:00.0: bridge window [io size 0xab000]: failed to
> > assign
> > [ 598.834590] pci 0000:2e:00.0: bridge window [io size 0xab000]: can't
> > assign; no space
> > [ 598.835088] pci 0000:2e:00.0: bridge window [io size 0xab000]: failed to
> > assign
> > [ 598.835592] pci 0000:2f:01.0: bridge window [mem
> > 0x6020000000-0x6031ffffff 64bit pref]: assigned
> > [ 598.836098] pci 0000:2f:01.0: bridge window [mem 0x6e000000-0x720fffff]:
> > assigned
> > [ 598.836600] pci 0000:2f:01.0: bridge window [io size 0xab000]: can't
> > assign; no space
> > [ 598.837097] pci 0000:2f:01.0: bridge window [io size 0xab000]: failed to
> > assign
> > [ 598.837585] pci 0000:2f:01.0: bridge window [io size 0xab000]: can't
> > assign; no space
> > [ 598.838073] pci 0000:2f:01.0: bridge window [io size 0xab000]: failed to
> > assign
> > [ 598.838559] pci 0000:30:00.0: BAR 1 [mem 0x6020000000-0x602fffffff 64bit
> > pref]: assigned
> > [ 598.839079] pci 0000:30:00.0: BAR 3 [mem 0x6030000000-0x6031ffffff 64bit
> > pref]: assigned
> > [ 598.839581] pci 0000:30:00.0: BAR 0 [mem 0x6e000000-0x6effffff]: assigned
> > [ 598.840063] pci 0000:30:00.0: ROM [mem 0x6f000000-0x6f07ffff pref]:
> > assigned
> > [ 598.840538] pci 0000:30:00.1: BAR 0 [mem 0x6f080000-0x6f083fff]: assigned
> > [ 598.841020] pci 0000:30:00.0: BAR 5 [io size 0x0080]: can't assign; no
> > space
> > [ 598.841496] pci 0000:30:00.0: BAR 5 [io size 0x0080]: failed to assign
> > [ 598.841974] pci 0000:30:00.0: BAR 5 [io size 0x0080]: can't assign; no
> > space
> > [ 598.842463] pci 0000:30:00.0: BAR 5 [io size 0x0080]: failed to assign
> > [ 598.842941] pci 0000:2f:01.0: PCI bridge to [bus 30]
> > [ 598.843429] pci 0000:2f:01.0: bridge window [mem 0x6e000000-0x720fffff]
> > [ 598.843918] pci 0000:2f:01.0: bridge window [mem
> > 0x6020000000-0x6031ffffff 64bit pref]
> > [ 598.844415] pci 0000:2e:00.0: PCI bridge to [bus 2f-30]
> > [ 598.844901] pci 0000:2e:00.0: bridge window [mem 0x6e000000-0x720fffff]
> > [ 598.845388] pci 0000:2e:00.0: bridge window [mem
> > 0x6020000000-0x6031ffffff 64bit pref]
> > [ 598.845890] pci 0000:2c:01.0: PCI bridge to [bus 2e-53]
> > [ 598.846369] pci 0000:2c:01.0: bridge window [mem 0x6e000000-0x720fffff]
> > [ 598.846845] pci 0000:2c:01.0: bridge window [mem
> > 0x6020000000-0x6031ffffff 64bit pref]
> > [ 598.847319] pci 0000:2b:00.0: PCI bridge to [bus 2c-53]
> > [ 598.847789] pci 0000:2b:00.0: bridge window [mem 0x6e000000-0x7a0fffff]
> > [ 598.848255] pci 0000:2b:00.0: bridge window [mem
> > 0x6020000000-0x6031ffffff 64bit pref]
> > [ 598.848720] pcieport 0000:00:07.1: PCI bridge to [bus 2b-53]
> > [ 598.849198] pcieport 0000:00:07.1: bridge window [mem
> > 0x6e000000-0x7a1fffff]
> > [ 598.849667] pcieport 0000:00:07.1: bridge window [mem
> > 0x6020000000-0x603bffffff 64bit pref]
> > [ 598.850136] PCI: No. 2 try to assign unassigned res
> > [ 598.850602] pci 0000:2c:00.0: disabling bridge window [mem
> > 0x00000000-0x000fffff 64bit pref disabled] to [bus 2d] (unused)
> > [ 598.851083] pci 0000:2c:00.0: disabling bridge window [mem
> > 0x00000000-0x000fffff disabled] to [bus 2d] (unused)
> > [ 598.851556] pci 0000:2c:01.0: bridge window [io size 0xab000] to [bus
> > 2e-53] add_size 155000
> > [ 598.852035] pci 0000:2b:00.0: bridge window [io size 0x200000] to [bus
> > 2c-53] add_size 155000
> > [ 598.852530] pcieport 0000:00:07.1: bridge window [io size 0x200000] to
> > [bus 2b-53] add_size 155000
> > [ 598.853014] pcieport 0000:00:07.1: bridge window [io size 0x355000]:
> > can't assign; no space
> > [ 598.853493] pcieport 0000:00:07.1: bridge window [io size 0x355000]:
> > failed to assign
> > [ 598.853971] pcieport 0000:00:07.1: bridge window [io size 0x200000]:
> > can't assign; no space
> > [ 598.854448] pcieport 0000:00:07.1: bridge window [io size 0x200000]:
> > failed to assign
> > [ 598.854921] pci 0000:2b:00.0: bridge window [io size 0x355000]: can't
> > assign; no space
> > [ 598.855401] pci 0000:2b:00.0: bridge window [io size 0x355000]: failed
> > to assign
> > [ 598.855896] pci 0000:2b:00.0: bridge window [io size 0x200000]: can't
> > assign; no space
> > [ 598.856376] pci 0000:2b:00.0: bridge window [io size 0x200000]: failed
> > to assign
> > [ 598.856847] pci 0000:2c:00.0: bridge window [io size 0x1000]: can't
> > assign; no space
> > [ 598.857319] pci 0000:2c:00.0: bridge window [io size 0x1000]: failed to
> > assign
> > [ 598.857788] pci 0000:2c:01.0: bridge window [io size 0x11c000]: can't
> > assign; no space
> > [ 598.858255] pci 0000:2c:01.0: bridge window [io size 0x11c000]: failed
> > to assign
> > [ 598.858722] pci 0000:2c:00.0: bridge window [io size 0x1000]: can't
> > assign; no space
> > [ 598.859209] pci 0000:2c:00.0: bridge window [io size 0x1000]: failed to
> > assign
> > [ 598.859677] pci 0000:2c:01.0: bridge window [io size 0x11c000]: can't
> > assign; no space
> > [ 598.860143] pci 0000:2c:01.0: bridge window [io size 0x11c000]: failed
> > to assign
> > [ 598.860609] pci 0000:2c:00.0: PCI bridge to [bus 2d]
> > [ 598.861088] pci 0000:2e:00.0: bridge window [io size 0x11c000]: can't
> > assign; no space
> > [ 598.861556] pci 0000:2e:00.0: bridge window [io size 0x11c000]: failed
> > to assign
> > [ 598.862018] pci 0000:2e:00.0: bridge window [io size 0x11c000]: can't
> > assign; no space
> > [ 598.862501] pci 0000:2e:00.0: bridge window [io size 0x11c000]: failed
> > to assign
> > [ 598.862970] pci 0000:2f:01.0: bridge window [io size 0x11c000]: can't
> > assign; no space
> > [ 598.863429] pci 0000:2f:01.0: bridge window [io size 0x11c000]: failed
> > to assign
> > [ 598.863891] pci 0000:2f:01.0: bridge window [io size 0x11c000]: can't
> > assign; no space
> > [ 598.864349] pci 0000:2f:01.0: bridge window [io size 0x11c000]: failed
> > to assign
> > [ 598.864802] pci 0000:30:00.0: BAR 5 [io size 0x0080]: can't assign; no
> > space
> > [ 598.865254] pci 0000:30:00.0: BAR 5 [io size 0x0080]: failed to assign
> > [ 598.865715] pci 0000:30:00.0: BAR 5 [io size 0x0080]: can't assign; no
> > space
> > [ 598.866163] pci 0000:30:00.0: BAR 5 [io size 0x0080]: failed to assign
> > [ 598.866615] pci 0000:2f:01.0: PCI bridge to [bus 30]
> > [ 598.867073] pci 0000:2f:01.0: bridge window [mem 0x6e000000-0x720fffff]
> > [ 598.867528] pci 0000:2f:01.0: bridge window [mem
> > 0x6020000000-0x6031ffffff 64bit pref]
> > [ 598.867992] pci 0000:2e:00.0: PCI bridge to [bus 2f-30]
> > [ 598.868448] pci 0000:2e:00.0: bridge window [mem 0x6e000000-0x720fffff]
> > [ 598.868907] pci 0000:2e:00.0: bridge window [mem
> > 0x6020000000-0x6031ffffff 64bit pref]
> > [ 598.869374] pci 0000:2c:01.0: PCI bridge to [bus 2e-53]
> > [ 598.869833] pci 0000:2c:01.0: bridge window [mem 0x6e000000-0x720fffff]
> > [ 598.870286] pci 0000:2c:01.0: bridge window [mem
> > 0x6020000000-0x6031ffffff 64bit pref]
> > [ 598.870749] pci 0000:2b:00.0: PCI bridge to [bus 2c-53]
> > [ 598.871209] pci 0000:2b:00.0: bridge window [mem 0x6e000000-0x7a0fffff]
> > [ 598.871670] pci 0000:2b:00.0: bridge window [mem
> > 0x6020000000-0x6031ffffff 64bit pref]
> > [ 598.872132] pcieport 0000:00:07.1: PCI bridge to [bus 2b-53]
> > [ 598.872613] pcieport 0000:00:07.1: bridge window [mem
> > 0x6e000000-0x7a1fffff]
> > [ 598.873080] pcieport 0000:00:07.1: bridge window [mem
> > 0x6020000000-0x603bffffff 64bit pref]
> > [ 598.873649] pcieport 0000:2b:00.0: enabling device (0000 -> 0002)
> > [ 598.874666] pcieport 0000:2c:01.0: enabling device (0000 -> 0002)
> > [ 598.875244] pcieport 0000:2c:01.0: pciehp: Slot #1 AttnBtn- PwrCtrl- MRL-
> > AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis- LLActRep+
> > [ 598.876454] pcieport 0000:2c:02.0: pciehp: Hotplug bridge without
> > secondary bus, ignoring
> > [ 598.877284] pcieport 0000:2c:03.0: pciehp: Hotplug bridge without
> > secondary bus, ignoring
> > [ 598.878335] pcieport 0000:2e:00.0: enabling device (0000 -> 0002)
> > [ 598.879210] pcieport 0000:2f:01.0: enabling device (0000 -> 0002)
> > [ 598.880224] nvidia 0000:30:00.0: enabling device (0000 -> 0002)
> > [ 598.880833] nvidia 0000:30:00.0: vgaarb: VGA decodes changed:
> > olddecodes=io+mem,decodes=none:owns=none
> > [ 599.171370] [drm] [nvidia-drm] [GPU ID 0x00003000] Loading driver
> > [ 599.172273] [drm] Initialized nvidia-drm 0.0.0 for 0000:30:00.0 on minor
> > 3
> > [ 599.172936] pci 0000:30:00.1: extending delay after power-on from D3hot
> > to 20 msec
> > [ 599.173650] pci 0000:30:00.1: D0 power state depends on 0000:30:00.0
> > [ 683.104898] Loading firmware: nvidia/595.71.05/gsp_ga10x.bin
> > [ 683.634039] Loading firmware: nvidia/595.71.05/gsp_ga10x.bin
> > [ 684.043158] Loading firmware: nvidia/595.71.05/gsp_ga10x.bin
> >
> > So, only one of the two hub-connected eGPUs are recognized.
> >
> >
> > pciehp: Hotplug bridge without secondary bus, ignoring <- This sounds less
> > promising.
> >
> >
> > lspci (after connecting hub):
> >
> > 00:00.0 Host bridge: Intel Corporation 12th Gen Core Processor Host
> > Bridge/DRAM Registers (rev 02)
> > 00:02.0 VGA compatible controller: Intel Corporation Alder Lake-P GT2 [Iris
> > Xe Graphics] (rev 0c)
> > 00:04.0 Signal processing controller: Intel Corporation Alder Lake
> > Innovation Platform Framework Processor Participant (rev 02)
> > 00:06.0 PCI bridge: Intel Corporation 12th Gen Core Processor PCI Express x4
> > Controller #0 (rev 02)
> > 00:07.0 PCI bridge: Intel Corporation Alder Lake-P Thunderbolt 4 PCI Express
> > Root Port #0 (rev 02)
> > 00:07.1 PCI bridge: Intel Corporation Alder Lake-P Thunderbolt 4 PCI Express
> > Root Port #1 (rev 02)
> > 00:07.2 PCI bridge: Intel Corporation Alder Lake-P Thunderbolt 4 PCI Express
> > Root Port #2 (rev 02)
> > 00:07.3 PCI bridge: Intel Corporation Alder Lake-P Thunderbolt 4 PCI Express
> > Root Port #3 (rev 02)
> > 00:08.0 System peripheral: Intel Corporation 12th Gen Core Processor
> > Gaussian & Neural Accelerator (rev 02)
> > 00:0a.0 Signal processing controller: Intel Corporation Platform Monitoring
> > Technology (rev 01)
> > 00:0d.0 USB controller: Intel Corporation Alder Lake-P Thunderbolt 4 USB
> > Controller (rev 02)
> > 00:0d.2 USB controller: Intel Corporation Alder Lake-P Thunderbolt 4 NHI #0
> > (rev 02)
> > 00:0d.3 USB controller: Intel Corporation Alder Lake-P Thunderbolt 4 NHI #1
> > (rev 02)
> > 00:14.0 USB controller: Intel Corporation Alder Lake PCH USB 3.2 xHCI Host
> > Controller (rev 01)
> > 00:14.2 RAM memory: Intel Corporation Alder Lake PCH Shared SRAM (rev 01)
> > 00:15.0 Serial bus controller: Intel Corporation Alder Lake PCH Serial IO
> > I2C Controller #0 (rev 01)
> > 00:15.1 Serial bus controller: Intel Corporation Alder Lake PCH Serial IO
> > I2C Controller #1 (rev 01)
> > 00:15.3 Serial bus controller: Intel Corporation Alder Lake PCH Serial IO
> > I2C Controller #3 (rev 01)
> > 00:16.0 Communication controller: Intel Corporation Alder Lake PCH HECI
> > Controller (rev 01)
> > 00:16.3 Serial controller: Intel Corporation Alder Lake AMT SOL Redirection
> > (rev 01)
> > 00:1d.0 PCI bridge: Intel Corporation Alder Lake PCI Express Root Port #9
> > (rev 01)
> > 00:1f.0 ISA bridge: Intel Corporation Alder Lake PCH eSPI Controller (rev
> > 01)
> > 00:1f.3 Audio device: Intel Corporation Alder Lake PCH-P High Definition
> > Audio Controller (rev 01)
> > 00:1f.4 SMBus: Intel Corporation Alder Lake PCH-P SMBus Host Controller (rev
> > 01)
> > 00:1f.5 Serial bus controller: Intel Corporation Alder Lake-P PCH SPI
> > Controller (rev 01)
> > 01:00.0 Non-Volatile memory controller: Samsung Electronics Co Ltd NVMe SSD
> > Controller PM9C1a (DRAM-less)
> > 02:00.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C step)
> > [Alpine Ridge 2C 2016] (rev 02)
> > 03:01.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C step)
> > [Alpine Ridge 2C 2016] (rev 02)
> > 04:00.0 VGA compatible controller: NVIDIA Corporation GA102 [GeForce RTX
> > 3090] (rev a1)
> > 04:00.1 Audio device: NVIDIA Corporation GA102 High Definition Audio
> > Controller (rev a1)
> > 2b:00.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
> > 2020] (rev 03)
> > 2c:00.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
> > 2020] (rev 03)
> > 2c:01.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
> > 2020] (rev 03)
> > 2c:02.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
> > 2020] (rev 03)
> > 2c:03.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
> > 2020] (rev 03)
> > 2c:04.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
> > 2020] (rev 03)
> > 2e:00.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C step)
> > [Alpine Ridge 2C 2016] (rev 02)
> > 2f:01.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C step)
> > [Alpine Ridge 2C 2016] (rev 02)
> > 30:00.0 VGA compatible controller: NVIDIA Corporation GA102 [GeForce RTX
> > 3090] (rev a1)
> > 30:00.1 Audio device: NVIDIA Corporation GA102 High Definition Audio
> > Controller (rev a1)
> > 7d:00.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C step)
> > [Alpine Ridge 2C 2016] (rev 02)
> > 7e:01.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C step)
> > [Alpine Ridge 2C 2016] (rev 02)
> > 7f:00.0 VGA compatible controller: NVIDIA Corporation GA102 [GeForce RTX
> > 3090 Ti] (rev a1)
> > 7f:00.1 Audio device: NVIDIA Corporation GA102 High Definition Audio
> > Controller (rev a1)
> > a6:00.0 Ethernet controller: Intel Corporation Ethernet Controller I226-V
> > (rev 04)
> >
> >
> > /proc/iomem after connecting hub
> >
> > 00000000-00000fff : Reserved
> > 00001000-0009efff : System RAM
> > 0009f000-000fffff : Reserved
> > 000a0000-000bffff : PCI Bus 0000:00
> > 000f0000-000fffff : System ROM
> > 00100000-3727bfff : System RAM
> > 3727c000-372cafff : Reserved
> > 372cb000-388b2fff : System RAM
> > 388b3000-388b3fff : Reserved
> > 388b4000-3b138fff : System RAM
> > 3b139000-3ba38fff : Reserved
> > 3ba39000-3d84efff : System RAM
> > 3d84f000-40a7efff : Reserved
> > 40a7f000-43a2efff : ACPI Non-volatile Storage
> > 43945000-43945fff : USBC000:00
> > 43a2f000-43afefff : ACPI Tables
> > 43aff000-43afffff : System RAM
> > 43b00000-47ffffff : Reserved
> > 49200000-493fffff : Reserved
> > 4a000000-503fffff : Reserved
> > 4c800000-503fffff : Graphics Stolen Memory
> > 50400000-bfffffff : PCI Bus 0000:00
> > 50400000-50400fff : 0000:00:1f.5
> > 50500000-507fffff : PCI Bus 0000:a6
> > 50500000-505fffff : 0000:a6:00.0
> > 50500000-505fffff : igc
> > 50600000-506fffff : 0000:a6:00.0
> > 50700000-50703fff : 0000:a6:00.0
> > 50700000-50703fff : igc
> > 52000000-5e1fffff : PCI Bus 0000:7d
> > 52000000-5e0fffff : PCI Bus 0000:7e
> > 52000000-5e0fffff : PCI Bus 0000:7f
> > 52000000-52ffffff : 0000:7f:00.0
> > 52000000-52ffffff : nvidia
> > 53000000-5307ffff : 0000:7f:00.0
> > 53080000-53083fff : 0000:7f:00.1
> > 60000000-6c1fffff : PCI Bus 0000:54
> > 6e000000-7a1fffff : PCI Bus 0000:2b
> > 6e000000-7a0fffff : PCI Bus 0000:2c
> > 6e000000-720fffff : PCI Bus 0000:2e
> > 6e000000-720fffff : PCI Bus 0000:2f
> > 6e000000-720fffff : PCI Bus 0000:30
> > 6e000000-6effffff : 0000:30:00.0
> > 6e000000-6effffff : nvidia
> > 6f000000-6f07ffff : 0000:30:00.0
> > 6f080000-6f083fff : 0000:30:00.1
> > 7a400000-7a4fffff : PCI Bus 0000:01
> > 7a400000-7a403fff : 0000:01:00.0
> > 7a400000-7a403fff : nvme
> > 7a600000-7a60ffff : 0000:00:14.0
> > 7a600000-7a60ffff : xhci-hcd
> > 7a611000-7a611fff : 0000:00:16.3
> > 7c000000-881fffff : PCI Bus 0000:02
> > 7c000000-880fffff : PCI Bus 0000:03
> > 7c000000-880fffff : PCI Bus 0000:04
> > 7c000000-7cffffff : 0000:04:00.0
> > 7c000000-7cffffff : nvidia
> > 7d000000-7d07ffff : 0000:04:00.0
> > 7d080000-7d083fff : 0000:04:00.1
> > c0000000-cfffffff : PCI ECAM 0000 [bus 00-ff]
> > c0000000-cfffffff : PNP0C02:01
> > fd000000-fd68ffff : PNP0C02:02
> > fd690000-fd69ffff : INTC1055:00
> > fd6a0000-fd6affff : INTC1055:00
> > fd6b0000-fd6cffff : PNP0C02:02
> > fd6d0000-fd6dffff : INTC1055:00
> > fd6e0000-fd6effff : INTC1055:00
> > fd6f0000-fdffffff : PNP0C02:02
> > fe000000-fe01ffff : PNP0C02:02
> > fe04c000-fe04ffff : PNP0C02:02
> > fe050000-fe0affff : PNP0C02:02
> > fe0d0000-fe0fffff : PNP0C02:02
> > fe200000-fe7fffff : PNP0C02:02
> > fec00000-fec003ff : IOAPIC 0
> > fed00000-fed003ff : HPET 0
> > fed00000-fed003ff : PNP0103:00
> > fed20000-fed7ffff : Reserved
> > fed40000-fed44fff : NTC0702:00
> > fed90000-fed90fff : dmar0
> > fed91000-fed91fff : dmar1
> > feda0000-feda0fff : PNP0C02:01
> > feda1000-feda1fff : PNP0C02:01
> > fedc0000-fedc7fff : PNP0C02:01
> > fee00000-feefffff : PNP0C02:01
> > ff000000-ffffffff : PNP0C02:02
> > 100000000-10afbfffff : System RAM
> > d6a000000-d6b1e52f7 : Kernel code
> > d6b200000-d6b7a0fff : Kernel rodata
> > d6b800000-d6bac0cff : Kernel data
> > d6c247000-d6c30ffff : Kernel bss
> > 10afc00000-10afffffff : RAM buffer
> > 4000000000-7fffffffff : PCI Bus 0000:00
> > 4000000000-400fffffff : 0000:00:02.0
> > 4010000000-4016ffffff : 0000:00:02.0
> > 4017000000-4017000fff : 0000:00:15.0
> > 4017000000-40170001ff : lpss_dev
> > 4017000000-40170001ff : i2c_designware.0 lpss_dev
> > 4017000200-40170002ff : lpss_priv
> > 4017000800-4017000fff : idma64.0
> > 4017001000-4017001fff : 0000:00:15.1
> > 4017001000-40170011ff : lpss_dev
> > 4017001000-40170011ff : i2c_designware.1 lpss_dev
> > 4017001200-40170012ff : lpss_priv
> > 4017001800-4017001fff : idma64.1
> > 4017002000-4017002fff : 0000:00:15.3
> > 4017002000-40170021ff : lpss_dev
> > 4017002000-40170021ff : i2c_designware.2 lpss_dev
> > 4017002200-40170022ff : lpss_priv
> > 4017002800-4017002fff : idma64.2
> > 4020000000-40ffffffff : 0000:00:02.0
> > 6000000000-601bffffff : PCI Bus 0000:02
> > 6000000000-6011ffffff : PCI Bus 0000:03
> > 6000000000-6011ffffff : PCI Bus 0000:04
> > 6000000000-600fffffff : 0000:04:00.0
> > 6010000000-6011ffffff : 0000:04:00.0
> > 6020000000-603bffffff : PCI Bus 0000:2b
> > 6020000000-6031ffffff : PCI Bus 0000:2c
> > 6020000000-6031ffffff : PCI Bus 0000:2e
> > 6020000000-6031ffffff : PCI Bus 0000:2f
> > 6020000000-6031ffffff : PCI Bus 0000:30
> > 6020000000-602fffffff : 0000:30:00.0
> > 6030000000-6031ffffff : 0000:30:00.0
> > 6040000000-605bffffff : PCI Bus 0000:54
> > 605c000000-605cffffff : 0000:00:02.0
> > 605d000000-605d0fffff : 0000:00:1f.3
> > 605d100000-605d13ffff : 0000:00:0d.3
> > 605d100000-605d13ffff : thunderbolt
> > 605d140000-605d17ffff : 0000:00:0d.2
> > 605d140000-605d17ffff : thunderbolt
> > 605d180000-605d19ffff : 0000:00:04.0
> > 605d180000-605d19ffff : proc_thermal
> > 605d1a0000-605d1affff : 0000:00:0d.0
> > 605d1a0000-605d1affff : xhci-hcd
> > 605d1b0000-605d1b7fff : 0000:00:0a.0
> > 605d1b8000-605d1bbfff : 0000:00:1f.3
> > 605d1bc000-605d1bffff : 0000:00:14.2
> > 605d1c0000-605d1c00ff : 0000:00:1f.4
> > 605d1c0000-605d1c00ff : i801_smbus
> > 605d1c1000-605d1c1fff : 0000:00:16.0
> > 605d1c1000-605d1c1fff : mei_me
> > 605d1c5000-605d1c5fff : 0000:00:14.2
> > 605d1c6000-605d1c6fff : 0000:00:0d.3
> > 605d1c7000-605d1c7fff : 0000:00:0d.2
> > 605d1c8000-605d1c8fff : 0000:00:08.0
> > 6060000000-607bffffff : PCI Bus 0000:7d
> > 6060000000-6071ffffff : PCI Bus 0000:7e
> > 6060000000-6071ffffff : PCI Bus 0000:7f
> > 6060000000-606fffffff : 0000:7f:00.0
> > 6070000000-6071ffffff : 0000:7f:00.0
> >
> >
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Connecting multiple TB3 eGPUs via USB4 hub?'
2026-06-09 12:08 ` Mika Westerberg
@ 2026-06-10 22:48 ` Dag B
2026-06-11 4:41 ` Mika Westerberg
0 siblings, 1 reply; 6+ messages in thread
From: Dag B @ 2026-06-10 22:48 UTC (permalink / raw)
To: Mika Westerberg, Bjorn Helgaas
Cc: linux-pci, linux-usb, Ilpo Järvinen, Lukas Wunner
On 6/9/26 14:08, Mika Westerberg wrote:
> Hi,
>
> On Mon, Jun 08, 2026 at 10:26:40AM -0500, Bjorn Helgaas wrote:
>> [+cc linux-usb (Thunderbolt maintainers), Ilpo, Lukas]
>>
>> On Sun, May 24, 2026 at 04:56:56PM +0200, Dag B wrote:
>>> I am attempting to connect two TB3 enclosures to the same USB4 port via a
>>> USB4 hub.
>>>
>>> I cannot figure out of this is in violation of the TB3, TB4 or USB4 spec.
>> I'm not aware of a spec issue here.
Thank you very much Bjorn, slightly more interesting trying to get it to
work then.
> It should be fine but typically PCIe resources for one tunneled PCIe root
> port may not be enough for multiple GPUs. Therefore I suggest to connect
> them directly to the host USB4 ports without a hub.
That makes perfect sense. Until you run out of physical ports. The
entire point of this exercise started with trying to connect a 5th 3090
to my fw13 motherboard. :-D
Hence the USB4 hub. But even with just the hub and two connected GPUs,
it fails.
For now, I have limited my testing to just the USB4 hub and either one
or two GPUs.
> Second thing is that you have bunch of PCIe related command line parameters
> that may affect. I suggest removing all of them, and retry. There is hardly
> any reason to add these - the kernel should be able to handle this by
> default.
Mhm. I have stripped the command line parameters for some of my tests.
It absolutely works with nothing extra for a single GPU. And it
absolutely did not work without command-line params and with 4 GPUs
when I started on this adventure. But that was around 6.16-6.17.
>
> Then provide full dmesg along with output of 'sudo lspci -vv' so we can
> look a the resource allocation.
This very quickly becomes a lot of data as I test various things. I put
a repo with various data up on github.
https://github.com/dagbdagb/usb4_to_tb3_troubleshooting/
If you truly want all this on the mailing list, please let me know.
>
>> Below it looks like you hot-added the hub. Does it make any
>> difference if everything is connected before boot?
Yes. With both GPUs connected at boot, none of them will work. With just
one, it works.
>>
>> Please don't filter the dmesg logs you collect. We can do that if
>> needed.
Noted.
If anything stands out in the kernel logs, let me know. And, of course,
if logs suggest that this simply isn't possible with the hardware I have
at hand.
I found this in the logs:
[ 38.769878] NVRM: The NVIDIA probe routine was not called for 2
device(s).
[ 38.770543] NVRM: This can occur when another driver was loaded and
NVRM: obtained ownership of the NVIDIA device(s).
These messages are no longer there after disabling some CONFIG_FB
options. (and so is my console...)
Makes for no difference in the end, though. 'BAR0 is 0M' (with two GPUs
connected at boot)
Dag B
>>> .... or, in case it is not:
>>>
>>> Can this work with current USB4/Thunderbolt drivers in Linux? (I am not
>>> worried about bandwidth limitations.)
>>>
>>>
>>> This appears to be too niche to find answers anywhere else. I would be very
>>> grateful for any clarifying answer here, really.
>>>
>>>
>>> Hardware
>>>
>>> - Framework 13 mb with 12th gen Alder Lake (Intel Corporation Alder Lake-P
>>> Thunderbolt 4 NHI) (4 USB4 ports)
>>>
>>> - Sonnettech Echo 5 hub (Intel Corporation Thunderbolt 4 Bridge [Goshen
>>> Ridge 2020] )
>>>
>>> - Razer Core X (Intel Corporation JHL6340 Thunderbolt 3 Bridge (C step)
>>> [Alpine Ridge 2C 2016])
>>>
>>> - GPUs are Nvidia RTX 3090. They expose two PCIe devices, the GPU and an
>>> audio device.
>>>
>>>
>>> Using kernel 7.0.10 with gentoo patches.
>>>
>>>
>>> Been playing *a lot* with various permutations of pci-related kernel
>>> options. Current options:
>>>
>>> pci=realloc=on,hpmmiosize=256M,hpiosize=2M,hpmemsize=1G,hpbussize=0x33,pcie_scan_all,big_root_window
>>>
>>>
>>> pcie_port_pm=off
>>>
>>> pcie_aspm.policy=performance
>>>
>>> thunderbolt.clx=0
>>>
>>>
>>>
>>> Booting with 2 eGPUS directly connected to separate USB4 ports. (pcie
>>> messages only):
>>>
>>> [ 0.000000] Command line: root=/dev/nvme0n1p2 pci=realloc=on,hpmmiosize=256M,hpiosize=2M,hpmemsize=1G,hpbussize=0x33,pcie_scan_all,big_root_window
>>> pcie_port_pm=off pcie_aspm.policy=performance thunderbolt.clx=0
>>> [ 0.082296] Kernel command line: pci=realloc=on,hpmmiosize=256M,hpiosize=2M,hpmemsize=1G,hpbussize=0x33,pcie_scan_all,big_root_window
>>> \
>>> [ 0.082297] Kernel command line: pcie_port_pm=off
>>> pcie_aspm.policy=performance \
>>> [ 0.864174] pcieport 0000:00:06.0: PME: Signaling with IRQ 122
>>> [ 0.864343] pcieport 0000:00:07.0: PME: Signaling with IRQ 123
>>> [ 0.864358] pcieport 0000:00:07.0: pciehp: Slot #3 AttnBtn- PwrCtrl- MRL-
>>> AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis- LLActRep+
>>> [ 0.864661] pcieport 0000:00:07.1: PME: Signaling with IRQ 124
>>> [ 0.864677] pcieport 0000:00:07.1: pciehp: Slot #4 AttnBtn- PwrCtrl- MRL-
>>> AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis- LLActRep+
>>> [ 0.864900] pcieport 0000:00:07.2: PME: Signaling with IRQ 125
>>> [ 0.864914] pcieport 0000:00:07.2: pciehp: Slot #5 AttnBtn- PwrCtrl- MRL-
>>> AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis- LLActRep+
>>> [ 0.865139] pcieport 0000:00:07.3: PME: Signaling with IRQ 126
>>> [ 0.865153] pcieport 0000:00:07.3: pciehp: Slot #6 AttnBtn- PwrCtrl- MRL-
>>> AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis- LLActRep+
>>> [ 0.865376] pcieport 0000:00:1d.0: PME: Signaling with IRQ 127
>>> [ 5.127515] pcieport 0000:00:07.3: pciehp: Slot(6): Card present
>>> [ 5.134225] pcieport 0000:00:07.0: pciehp: Slot(3): Card present
>>> [ 5.263158] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
>>> can't assign; no space
>>> [ 5.263178] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
>>> failed to assign
>>> [ 5.263197] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
>>> can't assign; no space
>>> [ 5.263215] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
>>> failed to assign
>>> [ 5.270527] pcieport 0000:00:07.3: PCI bridge to [bus 7d-a5]
>>> [ 5.270529] pcieport 0000:00:07.3: bridge window [mem
>>> 0x52000000-0x5e1fffff]
>>> [ 5.270531] pcieport 0000:00:07.3: bridge window [mem
>>> 0x6060000000-0x607bffffff 64bit pref]
>>> [ 5.270537] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
>>> can't assign; no space
>>> [ 5.270537] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
>>> failed to assign
>>> [ 5.270538] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
>>> can't assign; no space
>>> [ 5.270539] pcieport 0000:00:07.3: bridge window [io size 0x200000]:
>>> failed to assign
>>> [ 5.270577] pcieport 0000:00:07.3: PCI bridge to [bus 7d-a5]
>>> [ 5.270579] pcieport 0000:00:07.3: bridge window [mem
>>> 0x52000000-0x5e1fffff]
>>> [ 5.270581] pcieport 0000:00:07.3: bridge window [mem
>>> 0x6060000000-0x607bffffff 64bit pref]
>>> [ 5.270703] pcieport 0000:7d:00.0: enabling device (0000 -> 0002)
>>> [ 5.287127] pcieport 0000:7e:01.0: enabling device (0000 -> 0002)
>>> [ 5.325065] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
>>> can't assign; no space
>>> [ 5.325560] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
>>> failed to assign
>>> [ 5.326061] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
>>> can't assign; no space
>>> [ 5.326560] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
>>> failed to assign
>>> [ 5.340678] pcieport 0000:00:07.0: PCI bridge to [bus 02-2a]
>>> [ 5.340680] pcieport 0000:00:07.0: bridge window [mem
>>> 0x7c000000-0x881fffff]
>>> [ 5.340682] pcieport 0000:00:07.0: bridge window [mem
>>> 0x6000000000-0x601bffffff 64bit pref]
>>> [ 5.340688] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
>>> can't assign; no space
>>> [ 5.340689] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
>>> failed to assign
>>> [ 5.340690] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
>>> can't assign; no space
>>> [ 5.340690] pcieport 0000:00:07.0: bridge window [io size 0x200000]:
>>> failed to assign
>>> [ 5.340741] pcieport 0000:00:07.0: PCI bridge to [bus 02-2a]
>>> [ 5.340744] pcieport 0000:00:07.0: bridge window [mem
>>> 0x7c000000-0x881fffff]
>>> [ 5.340745] pcieport 0000:00:07.0: bridge window [mem
>>> 0x6000000000-0x601bffffff 64bit pref]
>>> [ 5.340866] pcieport 0000:02:00.0: enabling device (0000 -> 0002)
>>> [ 5.355410] pcieport 0000:03:01.0: enabling device (0000 -> 0002)
>>>
>>>
>>> Then, connecting the hub with two additional eGPUs to a third USB4 port (all
>>> messages):
>>>
>>> [ 596.449718] thunderbolt 0-3: new device found, vendor=0x8 device=0x5f
>>> [ 596.449771] thunderbolt 0-3: Sonnet Technologies, Inc. Echo 5 Thunderbolt
>>> 4 Hub
>>> [ 596.710380] thunderbolt 0-0:3.1: new retimer found, vendor=0x8087
>>> device=0x15ee
>>> [ 596.962295] usb 3-3: new high-speed USB device number 4 using xhci_hcd
>>> [ 597.156102] usb 3-3: New USB device found, idVendor=1d5c, idProduct=5801,
>>> bcdDevice= 1.01
>>> [ 597.156118] usb 3-3: New USB device strings: Mfr=1, Product=2,
>>> SerialNumber=0
>>> [ 597.156130] usb 3-3: Product: USB2.0 Hub
>>> [ 597.156138] usb 3-3: Manufacturer: Fresco Logic, Inc.
>>> [ 597.157120] hub 3-3:1.0: USB hub found
>>> [ 597.157152] hub 3-3:1.0: 6 ports detected
>>> [ 597.458933] usb 2-2: new SuperSpeed Plus Gen 2x1 USB device number 4
>>> using xhci_hcd
>>> [ 597.472670] usb 2-2: New USB device found, idVendor=8087, idProduct=0b40,
>>> bcdDevice=12.34
>>> [ 597.472687] usb 2-2: New USB device strings: Mfr=1, Product=2,
>>> SerialNumber=0
>>> [ 597.472700] usb 2-2: Product: USB3.0 Hub
>>> [ 597.472711] usb 2-2: Manufacturer: Intel Corporation.
>>> [ 597.473459] hub 2-2:1.0: USB hub found
>>> [ 597.473587] hub 2-2:1.0: 4 ports detected
>>> [ 597.559335] thunderbolt 0-303: new device found, vendor=0x127 device=0x1
>>> [ 597.559350] thunderbolt 0-303: Razer Core X
>>> [ 597.702310] usb 3-3.5: new full-speed USB device number 5 using xhci_hcd
>>> [ 597.801389] usb 3-3.5: New USB device found, idVendor=2a8c,
>>> idProduct=205f, bcdDevice=17.46
>>> [ 597.801406] usb 3-3.5: New USB device strings: Mfr=1, Product=2,
>>> SerialNumber=3
>>> [ 597.801418] usb 3-3.5: Product: Echo 5 Thunderbolt 4 Hub
>>> [ 597.801428] usb 3-3.5: Manufacturer: Sonnet Technologies,Inc.
>>> [ 597.801438] usb 3-3.5: SerialNumber: 11AD1D0A510D2E0D381E0B00
>>> [ 597.885632] usb 3-3.6: new high-speed USB device number 6 using xhci_hcd
>>> [ 597.983768] usb 3-3.6: New USB device found, idVendor=1d5c,
>>> idProduct=5530, bcdDevice= 1.01
>>> [ 597.983785] usb 3-3.6: New USB device strings: Mfr=1, Product=2,
>>> SerialNumber=0
>>> [ 597.983798] usb 3-3.6: Product: Frescologic VENDOR HID
>>> [ 597.983807] usb 3-3.6: Manufacturer: Frescologic
>>> [ 597.985769] hid-generic 0003:1D5C:5530.0002: hidraw1: USB HID v1.01
>>> Device [Frescologic Frescologic VENDOR HID] on usb-0000:00:14.0-3.6/input0
>>> [ 598.294042] thunderbolt 0-503: new device found, vendor=0x127 device=0x1
>>> [ 598.294057] thunderbolt 0-503: Razer Core X
>>> [ 598.619985] pcieport 0000:00:07.1: pciehp: Slot(4): Card present
>>> [ 598.619999] pcieport 0000:00:07.1: pciehp: Slot(4): Link Up
>>> [ 598.745860] pci 0000:2b:00.0: [8086:0b26] type 01 class 0x060400 PCIe
>>> Switch Upstream Port
>>> [ 598.745987] pci 0000:2b:00.0: PCI bridge to [bus 00]
>>> [ 598.746028] pci 0000:2b:00.0: bridge window [io 0x0000-0x0fff]
>>> [ 598.746061] pci 0000:2b:00.0: bridge window [mem 0x00000000-0x000fffff]
>>> [ 598.746113] pci 0000:2b:00.0: bridge window [mem 0x00000000-0x000fffff
>>> 64bit pref]
>>> [ 598.746173] pci 0000:2b:00.0: enabling Extended Tags
>>> [ 598.746450] pci 0000:2b:00.0: supports D1 D2
>>> [ 598.746471] pci 0000:2b:00.0: PME# supported from D0 D1 D2 D3hot D3cold
>>> [ 598.747002] pci 0000:2b:00.0: Adding to iommu group 22
>>> [ 598.755705] pci 0000:2b:00.0: bridge configuration invalid ([bus 00-00]),
>>> reconfiguring
>>> [ 598.755945] pci 0000:2c:00.0: [8086:0b26] type 01 class 0x060400 PCIe
>>> Switch Downstream Port
>>> [ 598.756014] pci 0000:2c:00.0: PCI bridge to [bus 00]
>>> [ 598.756039] pci 0000:2c:00.0: bridge window [io 0x0000-0x0fff]
>>> [ 598.756059] pci 0000:2c:00.0: bridge window [mem 0x00000000-0x000fffff]
>>> [ 598.756094] pci 0000:2c:00.0: bridge window [mem 0x00000000-0x000fffff
>>> 64bit pref]
>>> [ 598.756136] pci 0000:2c:00.0: enabling Extended Tags
>>> [ 598.756346] pci 0000:2c:00.0: supports D1 D2
>>> [ 598.756359] pci 0000:2c:00.0: PME# supported from D0 D1 D2 D3hot D3cold
>>> [ 598.756675] pci 0000:2c:00.0: Adding to iommu group 23
>>> [ 598.756854] pci 0000:2c:01.0: [8086:0b26] type 01 class 0x060400 PCIe
>>> Switch Downstream Port
>>> [ 598.756925] pci 0000:2c:01.0: PCI bridge to [bus 00]
>>> [ 598.756950] pci 0000:2c:01.0: bridge window [io 0x0000-0x0fff]
>>> [ 598.756970] pci 0000:2c:01.0: bridge window [mem 0x00000000-0x000fffff]
>>> [ 598.757863] pci 0000:2c:01.0: bridge window [mem 0x00000000-0x000fffff
>>> 64bit pref]
>>> [ 598.758743] pci 0000:2c:01.0: enabling Extended Tags
>>> [ 598.759822] pci 0000:2c:01.0: supports D1 D2
>>> [ 598.760599] pci 0000:2c:01.0: PME# supported from D0 D1 D2 D3hot D3cold
>>> [ 598.761582] pci 0000:2c:01.0: Adding to iommu group 24
>>> [ 598.762477] pci 0000:2c:02.0: [8086:0b26] type 01 class 0x060400 PCIe
>>> Switch Downstream Port
>>> [ 598.763270] pci 0000:2c:02.0: PCI bridge to [bus 00]
>>> [ 598.764010] pci 0000:2c:02.0: bridge window [io 0x0000-0x0fff]
>>> [ 598.764697] pci 0000:2c:02.0: bridge window [mem 0x00000000-0x000fffff]
>>> [ 598.765266] pci 0000:2c:02.0: bridge window [mem 0x00000000-0x000fffff
>>> 64bit pref]
>>> [ 598.765832] pci 0000:2c:02.0: enabling Extended Tags
>>> [ 598.766513] pci 0000:2c:02.0: supports D1 D2
>>> [ 598.767016] pci 0000:2c:02.0: PME# supported from D0 D1 D2 D3hot D3cold
>>> [ 598.767686] pci 0000:2c:02.0: Adding to iommu group 25
>>> [ 598.768272] pci 0000:2c:03.0: [8086:0b26] type 01 class 0x060400 PCIe
>>> Switch Downstream Port
>>> [ 598.768804] pci 0000:2c:03.0: PCI bridge to [bus 00]
>>> [ 598.769323] pci 0000:2c:03.0: bridge window [io 0x0000-0x0fff]
>>> [ 598.769815] pci 0000:2c:03.0: bridge window [mem 0x00000000-0x000fffff]
>>> [ 598.770317] pci 0000:2c:03.0: bridge window [mem 0x00000000-0x000fffff
>>> 64bit pref]
>>> [ 598.770816] pci 0000:2c:03.0: enabling Extended Tags
>>> [ 598.771451] pci 0000:2c:03.0: supports D1 D2
>>> [ 598.771929] pci 0000:2c:03.0: PME# supported from D0 D1 D2 D3hot D3cold
>>> [ 598.772596] pci 0000:2c:03.0: Adding to iommu group 26
>>> [ 598.773173] pci 0000:2c:04.0: [8086:0b26] type 01 class 0x060400 PCIe
>>> Switch Downstream Port
>>> [ 598.773694] pci 0000:2c:04.0: PCI bridge to [bus 00]
>>> [ 598.774196] pci 0000:2c:04.0: bridge window [io 0x0000-0x0fff]
>>> [ 598.774683] pci 0000:2c:04.0: bridge window [mem 0x00000000-0x000fffff]
>>> [ 598.775179] pci 0000:2c:04.0: bridge window [mem 0x00000000-0x000fffff
>>> 64bit pref]
>>> [ 598.775687] pci 0000:2c:04.0: enabling Extended Tags
>>> [ 598.776319] pci 0000:2c:04.0: supports D1 D2
>>> [ 598.776794] pci 0000:2c:04.0: PME# supported from D0 D1 D2 D3hot D3cold
>>> [ 598.777437] pci 0000:2c:04.0: Adding to iommu group 27
>>> [ 598.777985] pci 0000:2b:00.0: PCI bridge to [bus 2c-53]
>>> [ 598.778481] pci 0000:2c:00.0: bridge configuration invalid ([bus 00-00]),
>>> reconfiguring
>>> [ 598.778983] pci 0000:2c:01.0: bridge configuration invalid ([bus 00-00]),
>>> reconfiguring
>>> [ 598.779463] pci 0000:2c:02.0: bridge configuration invalid ([bus 00-00]),
>>> reconfiguring
>>> [ 598.779939] pci 0000:2c:03.0: bridge configuration invalid ([bus 00-00]),
>>> reconfiguring
>>> [ 598.780408] pci 0000:2c:04.0: bridge configuration invalid ([bus 00-00]),
>>> reconfiguring
>>> [ 598.780987] pci 0000:2c:00.0: PCI bridge to [bus 2d-53]
>>> [ 598.781458] pci_bus 0000:2d: busn_res: [bus 2d-53] end is updated to 2d
>>> [ 598.782096] pci 0000:2e:00.0: [8086:15da] type 01 class 0x060400 PCIe
>>> Switch Upstream Port
>>> [ 598.782628] pci 0000:2e:00.0: PCI bridge to [bus 00]
>>> [ 598.783089] pci 0000:2e:00.0: bridge window [io 0x0000-0x0fff]
>>> [ 598.783548] pci 0000:2e:00.0: bridge window [mem 0x00000000-0x000fffff]
>>> [ 598.784020] pci 0000:2e:00.0: bridge window [mem 0x00000000-0x000fffff
>>> 64bit pref]
>>> [ 598.784493] pci 0000:2e:00.0: enabling Extended Tags
>>> [ 598.785172] pci 0000:2e:00.0: supports D1 D2
>>> [ 598.785624] pci 0000:2e:00.0: PME# supported from D0 D1 D2 D3hot D3cold
>>> [ 598.786319] pci 0000:2e:00.0: Adding to iommu group 28
>>> [ 598.792407] pci 0000:2c:01.0: PCI bridge to [bus 2e-53]
>>> [ 598.792880] pci 0000:2e:00.0: bridge configuration invalid ([bus 00-00]),
>>> reconfiguring
>>> [ 598.793579] pci 0000:2f:01.0: [8086:15da] type 01 class 0x060400 PCIe
>>> Switch Downstream Port
>>> [ 598.794094] pci 0000:2f:01.0: PCI bridge to [bus 00]
>>> [ 598.794559] pci 0000:2f:01.0: bridge window [io 0x0000-0x0fff]
>>> [ 598.795014] pci 0000:2f:01.0: bridge window [mem 0x00000000-0x000fffff]
>>> [ 598.795485] pci 0000:2f:01.0: bridge window [mem 0x00000000-0x000fffff
>>> 64bit pref]
>>> [ 598.795981] pci 0000:2f:01.0: enabling Extended Tags
>>> [ 598.796665] pci 0000:2f:01.0: supports D1 D2
>>> [ 598.797111] pci 0000:2f:01.0: PME# supported from D0 D1 D2 D3hot D3cold
>>> [ 598.797785] pci 0000:2f:01.0: Adding to iommu group 29
>>> [ 598.798344] pci 0000:2e:00.0: PCI bridge to [bus 2f-53]
>>> [ 598.798826] pci 0000:2f:01.0: bridge configuration invalid ([bus 00-00]),
>>> reconfiguring
>>> [ 598.799576] pci 0000:30:00.0: [10de:2204] type 00 class 0x030000 PCIe
>>> Legacy Endpoint
>>> [ 598.800146] pci 0000:30:00.0: BAR 0 [mem 0x00000000-0x00ffffff]
>>> [ 598.800598] pci 0000:30:00.0: BAR 1 [mem 0x00000000-0x0fffffff 64bit
>>> pref]
>>> [ 598.801062] pci 0000:30:00.0: BAR 3 [mem 0x00000000-0x01ffffff 64bit
>>> pref]
>>> [ 598.801512] pci 0000:30:00.0: BAR 5 [io 0x0000-0x007f]
>>> [ 598.801961] pci 0000:30:00.0: ROM [mem 0x00000000-0x0007ffff pref]
>>> [ 598.802697] pci 0000:30:00.0: PME# supported from D0 D3hot
>>> [ 598.803421] pci 0000:30:00.0: 8.000 Gb/s available PCIe bandwidth,
>>> limited by 2.5 GT/s PCIe x4 link at 0000:00:07.1 (capable of 252.048 Gb/s
>>> with 16.0 GT/s PCIe x16 link)
>>> [ 598.804053] pci 0000:30:00.0: Adding to iommu group 29
>>> [ 598.804517] pci 0000:30:00.0: vgaarb: bridge control possible
>>> [ 598.804969] pci 0000:30:00.0: vgaarb: VGA device added:
>>> decodes=io+mem,owns=none,locks=none
>>> [ 598.805427] i915 0000:00:02.0: vgaarb: VGA decodes changed:
>>> olddecodes=none,decodes=none:owns=io+mem
>>> [ 598.806033] pci 0000:30:00.1: [10de:1aef] type 00 class 0x040300 PCIe
>>> Endpoint
>>> [ 598.806622] pci 0000:30:00.1: BAR 0 [mem 0x00000000-0x00003fff]
>>> [ 598.807434] pci 0000:30:00.1: Adding to iommu group 29
>>> [ 598.808118] pci 0000:2f:01.0: PCI bridge to [bus 30-53]
>>> [ 598.808614] pci_bus 0000:30: busn_res: [bus 30-53] end is updated to 30
>>> [ 598.809107] pci_bus 0000:2f: busn_res: [bus 2f-53] end is updated to 30
>>> [ 598.809575] pci_bus 0000:2e: busn_res: [bus 2e-53] end is updated to 53
>>> [ 598.810077] pci_bus 0000:54: busn_res: [bus 54-7c] end is updated to 7c
>>> [ 598.810714] pci_bus 0000:7d: busn_res: [bus 7d-a5] end is updated to a5
>>> [ 598.811226] pci_bus 0000:a6: busn_res: [bus a6] end is updated to a6
>>> [ 598.811682] pci_bus 0000:2c: busn_res: [bus 2c-53] end can not be updated
>>> to a6
>>> [ 598.812141] pci 0000:2c:00.0: disabling bridge window [mem
>>> 0x00000000-0x000fffff 64bit pref] to [bus 2d] (unused)
>>> [ 598.812621] pci 0000:2c:00.0: disabling bridge window [mem
>>> 0x00000000-0x000fffff] to [bus 2d] (unused)
>>> [ 598.813082] pci 0000:2c:01.0: bridge window [io 0x1000-0x1fff] to [bus
>>> 2e-53] add_size 1ff000
>>> [ 598.813544] pci 0000:2c:01.0: bridge window [mem 0x10000000-0x21ffffff
>>> 64bit pref] to [bus 2e-53] add_size 2e000000 add_align 10000000
>>> [ 598.814007] pci 0000:2c:01.0: bridge window [mem 0x01000000-0x020fffff]
>>> to [bus 2e-53] add_size 3ef00000 add_align 1000000
>>> [ 598.814474] pci 0000:2b:00.0: bridge window [io 0x1000-0x2fff] to [bus
>>> 2c-53] add_size 1ff000
>>> [ 598.814942] pci 0000:2b:00.0: bridge window [mem 0x10000000-0x21ffffff
>>> 64bit pref] to [bus 2c-53] add_size 2e000000 add_align 10000000
>>> [ 598.815414] pci 0000:2b:00.0: bridge window [mem 0x01000000-0x020fffff]
>>> to [bus 2c-53] add_size 3ef00000 add_align 1000000
>>> [ 598.815908] pcieport 0000:00:07.1: bridge window [io size 0x200000] to
>>> [bus 2b-53] add_size 1ff000
>>> [ 598.816393] pcieport 0000:00:07.1: bridge window [io size 0x3ff000]:
>>> can't assign; no space
>>> [ 598.816870] pcieport 0000:00:07.1: bridge window [io size 0x3ff000]:
>>> failed to assign
>>> [ 598.817346] pcieport 0000:00:07.1: bridge window [io size 0x200000]:
>>> can't assign; no space
>>> [ 598.817828] pcieport 0000:00:07.1: bridge window [io size 0x200000]:
>>> failed to assign
>>> [ 598.818304] pci 0000:2b:00.0: bridge window [mem size 0x40000000 64bit
>>> pref]: can't assign; no space
>>> [ 598.818785] pci 0000:2b:00.0: bridge window [mem size 0x40000000 64bit
>>> pref]: failed to assign
>>> [ 598.819281] pci 0000:2b:00.0: bridge window [mem 0x6e000000-0x7a0fffff]:
>>> assigned
>>> [ 598.819765] pci 0000:2b:00.0: bridge window [io size 0x200000]: can't
>>> assign; no space
>>> [ 598.820250] pci 0000:2b:00.0: bridge window [io size 0x200000]: failed
>>> to assign
>>> [ 598.820740] pci 0000:2b:00.0: bridge window [mem 0x6e000000-0x7a0fffff]:
>>> releasing
>>> [ 598.821235] pci 0000:2b:00.0: bridge window [mem
>>> 0x6020000000-0x6031ffffff 64bit pref]: assigned
>>> [ 598.821727] pci 0000:2b:00.0: bridge window [mem 0x6e000000-0x7a0fffff]:
>>> assigned
>>> [ 598.822227] pci 0000:2b:00.0: bridge window [io size 0x200000]: can't
>>> assign; no space
>>> [ 598.822722] pci 0000:2b:00.0: bridge window [io size 0x200000]: failed
>>> to assign
>>> [ 598.823206] pci 0000:2b:00.0: bridge window [mem
>>> 0x6020000000-0x6031ffffff 64bit pref]: failed to expand by 0x2e000000
>>> [ 598.823697] pci 0000:2b:00.0: bridge window [mem
>>> 0x6020000000-0x6031ffffff 64bit pref]: failed to add optional 2e000000
>>> [ 598.824186] pci 0000:2c:01.0: bridge window [mem size 0x40000000 64bit
>>> pref]: can't assign; no space
>>> [ 598.824679] pci 0000:2c:01.0: bridge window [mem size 0x40000000 64bit
>>> pref]: failed to assign
>>> [ 598.825173] pci 0000:2c:01.0: bridge window [mem 0x6e000000-0x720fffff]:
>>> assigned
>>> [ 598.825677] pci 0000:2c:00.0: bridge window [io size 0x1000]: can't
>>> assign; no space
>>> [ 598.826173] pci 0000:2c:00.0: bridge window [io size 0x1000]: failed to
>>> assign
>>> [ 598.826666] pci 0000:2c:01.0: bridge window [io size 0xab000]: can't
>>> assign; no space
>>> [ 598.827161] pci 0000:2c:01.0: bridge window [io size 0xab000]: failed to
>>> assign
>>> [ 598.827652] pci 0000:2c:01.0: bridge window [mem 0x6e000000-0x720fffff]:
>>> releasing
>>> [ 598.828140] pci 0000:2c:01.0: bridge window [mem
>>> 0x6020000000-0x6031ffffff 64bit pref]: assigned
>>> [ 598.828630] pci 0000:2c:01.0: bridge window [mem 0x6e000000-0x720fffff]:
>>> assigned
>>> [ 598.829132] pci 0000:2c:00.0: bridge window [io size 0x1000]: can't
>>> assign; no space
>>> [ 598.829623] pci 0000:2c:00.0: bridge window [io size 0x1000]: failed to
>>> assign
>>> [ 598.830116] pci 0000:2c:01.0: bridge window [io size 0xab000]: can't
>>> assign; no space
>>> [ 598.830606] pci 0000:2c:01.0: bridge window [io size 0xab000]: failed to
>>> assign
>>> [ 598.831099] pci 0000:2c:01.0: bridge window [mem
>>> 0x6020000000-0x6031ffffff 64bit pref]: failed to expand by 0x2e000000
>>> [ 598.831588] pci 0000:2c:01.0: bridge window [mem
>>> 0x6020000000-0x6031ffffff 64bit pref]: failed to add optional 2e000000
>>> [ 598.832080] pci 0000:2c:00.0: PCI bridge to [bus 2d]
>>> [ 598.832605] pci 0000:2e:00.0: bridge window [mem
>>> 0x6020000000-0x6031ffffff 64bit pref]: assigned
>>> [ 598.833106] pci 0000:2e:00.0: bridge window [mem 0x6e000000-0x720fffff]:
>>> assigned
>>> [ 598.833599] pci 0000:2e:00.0: bridge window [io size 0xab000]: can't
>>> assign; no space
>>> [ 598.834091] pci 0000:2e:00.0: bridge window [io size 0xab000]: failed to
>>> assign
>>> [ 598.834590] pci 0000:2e:00.0: bridge window [io size 0xab000]: can't
>>> assign; no space
>>> [ 598.835088] pci 0000:2e:00.0: bridge window [io size 0xab000]: failed to
>>> assign
>>> [ 598.835592] pci 0000:2f:01.0: bridge window [mem
>>> 0x6020000000-0x6031ffffff 64bit pref]: assigned
>>> [ 598.836098] pci 0000:2f:01.0: bridge window [mem 0x6e000000-0x720fffff]:
>>> assigned
>>> [ 598.836600] pci 0000:2f:01.0: bridge window [io size 0xab000]: can't
>>> assign; no space
>>> [ 598.837097] pci 0000:2f:01.0: bridge window [io size 0xab000]: failed to
>>> assign
>>> [ 598.837585] pci 0000:2f:01.0: bridge window [io size 0xab000]: can't
>>> assign; no space
>>> [ 598.838073] pci 0000:2f:01.0: bridge window [io size 0xab000]: failed to
>>> assign
>>> [ 598.838559] pci 0000:30:00.0: BAR 1 [mem 0x6020000000-0x602fffffff 64bit
>>> pref]: assigned
>>> [ 598.839079] pci 0000:30:00.0: BAR 3 [mem 0x6030000000-0x6031ffffff 64bit
>>> pref]: assigned
>>> [ 598.839581] pci 0000:30:00.0: BAR 0 [mem 0x6e000000-0x6effffff]: assigned
>>> [ 598.840063] pci 0000:30:00.0: ROM [mem 0x6f000000-0x6f07ffff pref]:
>>> assigned
>>> [ 598.840538] pci 0000:30:00.1: BAR 0 [mem 0x6f080000-0x6f083fff]: assigned
>>> [ 598.841020] pci 0000:30:00.0: BAR 5 [io size 0x0080]: can't assign; no
>>> space
>>> [ 598.841496] pci 0000:30:00.0: BAR 5 [io size 0x0080]: failed to assign
>>> [ 598.841974] pci 0000:30:00.0: BAR 5 [io size 0x0080]: can't assign; no
>>> space
>>> [ 598.842463] pci 0000:30:00.0: BAR 5 [io size 0x0080]: failed to assign
>>> [ 598.842941] pci 0000:2f:01.0: PCI bridge to [bus 30]
>>> [ 598.843429] pci 0000:2f:01.0: bridge window [mem 0x6e000000-0x720fffff]
>>> [ 598.843918] pci 0000:2f:01.0: bridge window [mem
>>> 0x6020000000-0x6031ffffff 64bit pref]
>>> [ 598.844415] pci 0000:2e:00.0: PCI bridge to [bus 2f-30]
>>> [ 598.844901] pci 0000:2e:00.0: bridge window [mem 0x6e000000-0x720fffff]
>>> [ 598.845388] pci 0000:2e:00.0: bridge window [mem
>>> 0x6020000000-0x6031ffffff 64bit pref]
>>> [ 598.845890] pci 0000:2c:01.0: PCI bridge to [bus 2e-53]
>>> [ 598.846369] pci 0000:2c:01.0: bridge window [mem 0x6e000000-0x720fffff]
>>> [ 598.846845] pci 0000:2c:01.0: bridge window [mem
>>> 0x6020000000-0x6031ffffff 64bit pref]
>>> [ 598.847319] pci 0000:2b:00.0: PCI bridge to [bus 2c-53]
>>> [ 598.847789] pci 0000:2b:00.0: bridge window [mem 0x6e000000-0x7a0fffff]
>>> [ 598.848255] pci 0000:2b:00.0: bridge window [mem
>>> 0x6020000000-0x6031ffffff 64bit pref]
>>> [ 598.848720] pcieport 0000:00:07.1: PCI bridge to [bus 2b-53]
>>> [ 598.849198] pcieport 0000:00:07.1: bridge window [mem
>>> 0x6e000000-0x7a1fffff]
>>> [ 598.849667] pcieport 0000:00:07.1: bridge window [mem
>>> 0x6020000000-0x603bffffff 64bit pref]
>>> [ 598.850136] PCI: No. 2 try to assign unassigned res
>>> [ 598.850602] pci 0000:2c:00.0: disabling bridge window [mem
>>> 0x00000000-0x000fffff 64bit pref disabled] to [bus 2d] (unused)
>>> [ 598.851083] pci 0000:2c:00.0: disabling bridge window [mem
>>> 0x00000000-0x000fffff disabled] to [bus 2d] (unused)
>>> [ 598.851556] pci 0000:2c:01.0: bridge window [io size 0xab000] to [bus
>>> 2e-53] add_size 155000
>>> [ 598.852035] pci 0000:2b:00.0: bridge window [io size 0x200000] to [bus
>>> 2c-53] add_size 155000
>>> [ 598.852530] pcieport 0000:00:07.1: bridge window [io size 0x200000] to
>>> [bus 2b-53] add_size 155000
>>> [ 598.853014] pcieport 0000:00:07.1: bridge window [io size 0x355000]:
>>> can't assign; no space
>>> [ 598.853493] pcieport 0000:00:07.1: bridge window [io size 0x355000]:
>>> failed to assign
>>> [ 598.853971] pcieport 0000:00:07.1: bridge window [io size 0x200000]:
>>> can't assign; no space
>>> [ 598.854448] pcieport 0000:00:07.1: bridge window [io size 0x200000]:
>>> failed to assign
>>> [ 598.854921] pci 0000:2b:00.0: bridge window [io size 0x355000]: can't
>>> assign; no space
>>> [ 598.855401] pci 0000:2b:00.0: bridge window [io size 0x355000]: failed
>>> to assign
>>> [ 598.855896] pci 0000:2b:00.0: bridge window [io size 0x200000]: can't
>>> assign; no space
>>> [ 598.856376] pci 0000:2b:00.0: bridge window [io size 0x200000]: failed
>>> to assign
>>> [ 598.856847] pci 0000:2c:00.0: bridge window [io size 0x1000]: can't
>>> assign; no space
>>> [ 598.857319] pci 0000:2c:00.0: bridge window [io size 0x1000]: failed to
>>> assign
>>> [ 598.857788] pci 0000:2c:01.0: bridge window [io size 0x11c000]: can't
>>> assign; no space
>>> [ 598.858255] pci 0000:2c:01.0: bridge window [io size 0x11c000]: failed
>>> to assign
>>> [ 598.858722] pci 0000:2c:00.0: bridge window [io size 0x1000]: can't
>>> assign; no space
>>> [ 598.859209] pci 0000:2c:00.0: bridge window [io size 0x1000]: failed to
>>> assign
>>> [ 598.859677] pci 0000:2c:01.0: bridge window [io size 0x11c000]: can't
>>> assign; no space
>>> [ 598.860143] pci 0000:2c:01.0: bridge window [io size 0x11c000]: failed
>>> to assign
>>> [ 598.860609] pci 0000:2c:00.0: PCI bridge to [bus 2d]
>>> [ 598.861088] pci 0000:2e:00.0: bridge window [io size 0x11c000]: can't
>>> assign; no space
>>> [ 598.861556] pci 0000:2e:00.0: bridge window [io size 0x11c000]: failed
>>> to assign
>>> [ 598.862018] pci 0000:2e:00.0: bridge window [io size 0x11c000]: can't
>>> assign; no space
>>> [ 598.862501] pci 0000:2e:00.0: bridge window [io size 0x11c000]: failed
>>> to assign
>>> [ 598.862970] pci 0000:2f:01.0: bridge window [io size 0x11c000]: can't
>>> assign; no space
>>> [ 598.863429] pci 0000:2f:01.0: bridge window [io size 0x11c000]: failed
>>> to assign
>>> [ 598.863891] pci 0000:2f:01.0: bridge window [io size 0x11c000]: can't
>>> assign; no space
>>> [ 598.864349] pci 0000:2f:01.0: bridge window [io size 0x11c000]: failed
>>> to assign
>>> [ 598.864802] pci 0000:30:00.0: BAR 5 [io size 0x0080]: can't assign; no
>>> space
>>> [ 598.865254] pci 0000:30:00.0: BAR 5 [io size 0x0080]: failed to assign
>>> [ 598.865715] pci 0000:30:00.0: BAR 5 [io size 0x0080]: can't assign; no
>>> space
>>> [ 598.866163] pci 0000:30:00.0: BAR 5 [io size 0x0080]: failed to assign
>>> [ 598.866615] pci 0000:2f:01.0: PCI bridge to [bus 30]
>>> [ 598.867073] pci 0000:2f:01.0: bridge window [mem 0x6e000000-0x720fffff]
>>> [ 598.867528] pci 0000:2f:01.0: bridge window [mem
>>> 0x6020000000-0x6031ffffff 64bit pref]
>>> [ 598.867992] pci 0000:2e:00.0: PCI bridge to [bus 2f-30]
>>> [ 598.868448] pci 0000:2e:00.0: bridge window [mem 0x6e000000-0x720fffff]
>>> [ 598.868907] pci 0000:2e:00.0: bridge window [mem
>>> 0x6020000000-0x6031ffffff 64bit pref]
>>> [ 598.869374] pci 0000:2c:01.0: PCI bridge to [bus 2e-53]
>>> [ 598.869833] pci 0000:2c:01.0: bridge window [mem 0x6e000000-0x720fffff]
>>> [ 598.870286] pci 0000:2c:01.0: bridge window [mem
>>> 0x6020000000-0x6031ffffff 64bit pref]
>>> [ 598.870749] pci 0000:2b:00.0: PCI bridge to [bus 2c-53]
>>> [ 598.871209] pci 0000:2b:00.0: bridge window [mem 0x6e000000-0x7a0fffff]
>>> [ 598.871670] pci 0000:2b:00.0: bridge window [mem
>>> 0x6020000000-0x6031ffffff 64bit pref]
>>> [ 598.872132] pcieport 0000:00:07.1: PCI bridge to [bus 2b-53]
>>> [ 598.872613] pcieport 0000:00:07.1: bridge window [mem
>>> 0x6e000000-0x7a1fffff]
>>> [ 598.873080] pcieport 0000:00:07.1: bridge window [mem
>>> 0x6020000000-0x603bffffff 64bit pref]
>>> [ 598.873649] pcieport 0000:2b:00.0: enabling device (0000 -> 0002)
>>> [ 598.874666] pcieport 0000:2c:01.0: enabling device (0000 -> 0002)
>>> [ 598.875244] pcieport 0000:2c:01.0: pciehp: Slot #1 AttnBtn- PwrCtrl- MRL-
>>> AttnInd- PwrInd- HotPlug+ Surprise+ Interlock- NoCompl+ IbPresDis- LLActRep+
>>> [ 598.876454] pcieport 0000:2c:02.0: pciehp: Hotplug bridge without
>>> secondary bus, ignoring
>>> [ 598.877284] pcieport 0000:2c:03.0: pciehp: Hotplug bridge without
>>> secondary bus, ignoring
>>> [ 598.878335] pcieport 0000:2e:00.0: enabling device (0000 -> 0002)
>>> [ 598.879210] pcieport 0000:2f:01.0: enabling device (0000 -> 0002)
>>> [ 598.880224] nvidia 0000:30:00.0: enabling device (0000 -> 0002)
>>> [ 598.880833] nvidia 0000:30:00.0: vgaarb: VGA decodes changed:
>>> olddecodes=io+mem,decodes=none:owns=none
>>> [ 599.171370] [drm] [nvidia-drm] [GPU ID 0x00003000] Loading driver
>>> [ 599.172273] [drm] Initialized nvidia-drm 0.0.0 for 0000:30:00.0 on minor
>>> 3
>>> [ 599.172936] pci 0000:30:00.1: extending delay after power-on from D3hot
>>> to 20 msec
>>> [ 599.173650] pci 0000:30:00.1: D0 power state depends on 0000:30:00.0
>>> [ 683.104898] Loading firmware: nvidia/595.71.05/gsp_ga10x.bin
>>> [ 683.634039] Loading firmware: nvidia/595.71.05/gsp_ga10x.bin
>>> [ 684.043158] Loading firmware: nvidia/595.71.05/gsp_ga10x.bin
>>>
>>> So, only one of the two hub-connected eGPUs are recognized.
>>>
>>>
>>> pciehp: Hotplug bridge without secondary bus, ignoring <- This sounds less
>>> promising.
>>>
>>>
>>> lspci (after connecting hub):
>>>
>>> 00:00.0 Host bridge: Intel Corporation 12th Gen Core Processor Host
>>> Bridge/DRAM Registers (rev 02)
>>> 00:02.0 VGA compatible controller: Intel Corporation Alder Lake-P GT2 [Iris
>>> Xe Graphics] (rev 0c)
>>> 00:04.0 Signal processing controller: Intel Corporation Alder Lake
>>> Innovation Platform Framework Processor Participant (rev 02)
>>> 00:06.0 PCI bridge: Intel Corporation 12th Gen Core Processor PCI Express x4
>>> Controller #0 (rev 02)
>>> 00:07.0 PCI bridge: Intel Corporation Alder Lake-P Thunderbolt 4 PCI Express
>>> Root Port #0 (rev 02)
>>> 00:07.1 PCI bridge: Intel Corporation Alder Lake-P Thunderbolt 4 PCI Express
>>> Root Port #1 (rev 02)
>>> 00:07.2 PCI bridge: Intel Corporation Alder Lake-P Thunderbolt 4 PCI Express
>>> Root Port #2 (rev 02)
>>> 00:07.3 PCI bridge: Intel Corporation Alder Lake-P Thunderbolt 4 PCI Express
>>> Root Port #3 (rev 02)
>>> 00:08.0 System peripheral: Intel Corporation 12th Gen Core Processor
>>> Gaussian & Neural Accelerator (rev 02)
>>> 00:0a.0 Signal processing controller: Intel Corporation Platform Monitoring
>>> Technology (rev 01)
>>> 00:0d.0 USB controller: Intel Corporation Alder Lake-P Thunderbolt 4 USB
>>> Controller (rev 02)
>>> 00:0d.2 USB controller: Intel Corporation Alder Lake-P Thunderbolt 4 NHI #0
>>> (rev 02)
>>> 00:0d.3 USB controller: Intel Corporation Alder Lake-P Thunderbolt 4 NHI #1
>>> (rev 02)
>>> 00:14.0 USB controller: Intel Corporation Alder Lake PCH USB 3.2 xHCI Host
>>> Controller (rev 01)
>>> 00:14.2 RAM memory: Intel Corporation Alder Lake PCH Shared SRAM (rev 01)
>>> 00:15.0 Serial bus controller: Intel Corporation Alder Lake PCH Serial IO
>>> I2C Controller #0 (rev 01)
>>> 00:15.1 Serial bus controller: Intel Corporation Alder Lake PCH Serial IO
>>> I2C Controller #1 (rev 01)
>>> 00:15.3 Serial bus controller: Intel Corporation Alder Lake PCH Serial IO
>>> I2C Controller #3 (rev 01)
>>> 00:16.0 Communication controller: Intel Corporation Alder Lake PCH HECI
>>> Controller (rev 01)
>>> 00:16.3 Serial controller: Intel Corporation Alder Lake AMT SOL Redirection
>>> (rev 01)
>>> 00:1d.0 PCI bridge: Intel Corporation Alder Lake PCI Express Root Port #9
>>> (rev 01)
>>> 00:1f.0 ISA bridge: Intel Corporation Alder Lake PCH eSPI Controller (rev
>>> 01)
>>> 00:1f.3 Audio device: Intel Corporation Alder Lake PCH-P High Definition
>>> Audio Controller (rev 01)
>>> 00:1f.4 SMBus: Intel Corporation Alder Lake PCH-P SMBus Host Controller (rev
>>> 01)
>>> 00:1f.5 Serial bus controller: Intel Corporation Alder Lake-P PCH SPI
>>> Controller (rev 01)
>>> 01:00.0 Non-Volatile memory controller: Samsung Electronics Co Ltd NVMe SSD
>>> Controller PM9C1a (DRAM-less)
>>> 02:00.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C step)
>>> [Alpine Ridge 2C 2016] (rev 02)
>>> 03:01.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C step)
>>> [Alpine Ridge 2C 2016] (rev 02)
>>> 04:00.0 VGA compatible controller: NVIDIA Corporation GA102 [GeForce RTX
>>> 3090] (rev a1)
>>> 04:00.1 Audio device: NVIDIA Corporation GA102 High Definition Audio
>>> Controller (rev a1)
>>> 2b:00.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
>>> 2020] (rev 03)
>>> 2c:00.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
>>> 2020] (rev 03)
>>> 2c:01.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
>>> 2020] (rev 03)
>>> 2c:02.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
>>> 2020] (rev 03)
>>> 2c:03.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
>>> 2020] (rev 03)
>>> 2c:04.0 PCI bridge: Intel Corporation Thunderbolt 4 Bridge [Goshen Ridge
>>> 2020] (rev 03)
>>> 2e:00.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C step)
>>> [Alpine Ridge 2C 2016] (rev 02)
>>> 2f:01.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C step)
>>> [Alpine Ridge 2C 2016] (rev 02)
>>> 30:00.0 VGA compatible controller: NVIDIA Corporation GA102 [GeForce RTX
>>> 3090] (rev a1)
>>> 30:00.1 Audio device: NVIDIA Corporation GA102 High Definition Audio
>>> Controller (rev a1)
>>> 7d:00.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C step)
>>> [Alpine Ridge 2C 2016] (rev 02)
>>> 7e:01.0 PCI bridge: Intel Corporation JHL6340 Thunderbolt 3 Bridge (C step)
>>> [Alpine Ridge 2C 2016] (rev 02)
>>> 7f:00.0 VGA compatible controller: NVIDIA Corporation GA102 [GeForce RTX
>>> 3090 Ti] (rev a1)
>>> 7f:00.1 Audio device: NVIDIA Corporation GA102 High Definition Audio
>>> Controller (rev a1)
>>> a6:00.0 Ethernet controller: Intel Corporation Ethernet Controller I226-V
>>> (rev 04)
>>>
>>>
>>> /proc/iomem after connecting hub
>>>
>>> 00000000-00000fff : Reserved
>>> 00001000-0009efff : System RAM
>>> 0009f000-000fffff : Reserved
>>> 000a0000-000bffff : PCI Bus 0000:00
>>> 000f0000-000fffff : System ROM
>>> 00100000-3727bfff : System RAM
>>> 3727c000-372cafff : Reserved
>>> 372cb000-388b2fff : System RAM
>>> 388b3000-388b3fff : Reserved
>>> 388b4000-3b138fff : System RAM
>>> 3b139000-3ba38fff : Reserved
>>> 3ba39000-3d84efff : System RAM
>>> 3d84f000-40a7efff : Reserved
>>> 40a7f000-43a2efff : ACPI Non-volatile Storage
>>> 43945000-43945fff : USBC000:00
>>> 43a2f000-43afefff : ACPI Tables
>>> 43aff000-43afffff : System RAM
>>> 43b00000-47ffffff : Reserved
>>> 49200000-493fffff : Reserved
>>> 4a000000-503fffff : Reserved
>>> 4c800000-503fffff : Graphics Stolen Memory
>>> 50400000-bfffffff : PCI Bus 0000:00
>>> 50400000-50400fff : 0000:00:1f.5
>>> 50500000-507fffff : PCI Bus 0000:a6
>>> 50500000-505fffff : 0000:a6:00.0
>>> 50500000-505fffff : igc
>>> 50600000-506fffff : 0000:a6:00.0
>>> 50700000-50703fff : 0000:a6:00.0
>>> 50700000-50703fff : igc
>>> 52000000-5e1fffff : PCI Bus 0000:7d
>>> 52000000-5e0fffff : PCI Bus 0000:7e
>>> 52000000-5e0fffff : PCI Bus 0000:7f
>>> 52000000-52ffffff : 0000:7f:00.0
>>> 52000000-52ffffff : nvidia
>>> 53000000-5307ffff : 0000:7f:00.0
>>> 53080000-53083fff : 0000:7f:00.1
>>> 60000000-6c1fffff : PCI Bus 0000:54
>>> 6e000000-7a1fffff : PCI Bus 0000:2b
>>> 6e000000-7a0fffff : PCI Bus 0000:2c
>>> 6e000000-720fffff : PCI Bus 0000:2e
>>> 6e000000-720fffff : PCI Bus 0000:2f
>>> 6e000000-720fffff : PCI Bus 0000:30
>>> 6e000000-6effffff : 0000:30:00.0
>>> 6e000000-6effffff : nvidia
>>> 6f000000-6f07ffff : 0000:30:00.0
>>> 6f080000-6f083fff : 0000:30:00.1
>>> 7a400000-7a4fffff : PCI Bus 0000:01
>>> 7a400000-7a403fff : 0000:01:00.0
>>> 7a400000-7a403fff : nvme
>>> 7a600000-7a60ffff : 0000:00:14.0
>>> 7a600000-7a60ffff : xhci-hcd
>>> 7a611000-7a611fff : 0000:00:16.3
>>> 7c000000-881fffff : PCI Bus 0000:02
>>> 7c000000-880fffff : PCI Bus 0000:03
>>> 7c000000-880fffff : PCI Bus 0000:04
>>> 7c000000-7cffffff : 0000:04:00.0
>>> 7c000000-7cffffff : nvidia
>>> 7d000000-7d07ffff : 0000:04:00.0
>>> 7d080000-7d083fff : 0000:04:00.1
>>> c0000000-cfffffff : PCI ECAM 0000 [bus 00-ff]
>>> c0000000-cfffffff : PNP0C02:01
>>> fd000000-fd68ffff : PNP0C02:02
>>> fd690000-fd69ffff : INTC1055:00
>>> fd6a0000-fd6affff : INTC1055:00
>>> fd6b0000-fd6cffff : PNP0C02:02
>>> fd6d0000-fd6dffff : INTC1055:00
>>> fd6e0000-fd6effff : INTC1055:00
>>> fd6f0000-fdffffff : PNP0C02:02
>>> fe000000-fe01ffff : PNP0C02:02
>>> fe04c000-fe04ffff : PNP0C02:02
>>> fe050000-fe0affff : PNP0C02:02
>>> fe0d0000-fe0fffff : PNP0C02:02
>>> fe200000-fe7fffff : PNP0C02:02
>>> fec00000-fec003ff : IOAPIC 0
>>> fed00000-fed003ff : HPET 0
>>> fed00000-fed003ff : PNP0103:00
>>> fed20000-fed7ffff : Reserved
>>> fed40000-fed44fff : NTC0702:00
>>> fed90000-fed90fff : dmar0
>>> fed91000-fed91fff : dmar1
>>> feda0000-feda0fff : PNP0C02:01
>>> feda1000-feda1fff : PNP0C02:01
>>> fedc0000-fedc7fff : PNP0C02:01
>>> fee00000-feefffff : PNP0C02:01
>>> ff000000-ffffffff : PNP0C02:02
>>> 100000000-10afbfffff : System RAM
>>> d6a000000-d6b1e52f7 : Kernel code
>>> d6b200000-d6b7a0fff : Kernel rodata
>>> d6b800000-d6bac0cff : Kernel data
>>> d6c247000-d6c30ffff : Kernel bss
>>> 10afc00000-10afffffff : RAM buffer
>>> 4000000000-7fffffffff : PCI Bus 0000:00
>>> 4000000000-400fffffff : 0000:00:02.0
>>> 4010000000-4016ffffff : 0000:00:02.0
>>> 4017000000-4017000fff : 0000:00:15.0
>>> 4017000000-40170001ff : lpss_dev
>>> 4017000000-40170001ff : i2c_designware.0 lpss_dev
>>> 4017000200-40170002ff : lpss_priv
>>> 4017000800-4017000fff : idma64.0
>>> 4017001000-4017001fff : 0000:00:15.1
>>> 4017001000-40170011ff : lpss_dev
>>> 4017001000-40170011ff : i2c_designware.1 lpss_dev
>>> 4017001200-40170012ff : lpss_priv
>>> 4017001800-4017001fff : idma64.1
>>> 4017002000-4017002fff : 0000:00:15.3
>>> 4017002000-40170021ff : lpss_dev
>>> 4017002000-40170021ff : i2c_designware.2 lpss_dev
>>> 4017002200-40170022ff : lpss_priv
>>> 4017002800-4017002fff : idma64.2
>>> 4020000000-40ffffffff : 0000:00:02.0
>>> 6000000000-601bffffff : PCI Bus 0000:02
>>> 6000000000-6011ffffff : PCI Bus 0000:03
>>> 6000000000-6011ffffff : PCI Bus 0000:04
>>> 6000000000-600fffffff : 0000:04:00.0
>>> 6010000000-6011ffffff : 0000:04:00.0
>>> 6020000000-603bffffff : PCI Bus 0000:2b
>>> 6020000000-6031ffffff : PCI Bus 0000:2c
>>> 6020000000-6031ffffff : PCI Bus 0000:2e
>>> 6020000000-6031ffffff : PCI Bus 0000:2f
>>> 6020000000-6031ffffff : PCI Bus 0000:30
>>> 6020000000-602fffffff : 0000:30:00.0
>>> 6030000000-6031ffffff : 0000:30:00.0
>>> 6040000000-605bffffff : PCI Bus 0000:54
>>> 605c000000-605cffffff : 0000:00:02.0
>>> 605d000000-605d0fffff : 0000:00:1f.3
>>> 605d100000-605d13ffff : 0000:00:0d.3
>>> 605d100000-605d13ffff : thunderbolt
>>> 605d140000-605d17ffff : 0000:00:0d.2
>>> 605d140000-605d17ffff : thunderbolt
>>> 605d180000-605d19ffff : 0000:00:04.0
>>> 605d180000-605d19ffff : proc_thermal
>>> 605d1a0000-605d1affff : 0000:00:0d.0
>>> 605d1a0000-605d1affff : xhci-hcd
>>> 605d1b0000-605d1b7fff : 0000:00:0a.0
>>> 605d1b8000-605d1bbfff : 0000:00:1f.3
>>> 605d1bc000-605d1bffff : 0000:00:14.2
>>> 605d1c0000-605d1c00ff : 0000:00:1f.4
>>> 605d1c0000-605d1c00ff : i801_smbus
>>> 605d1c1000-605d1c1fff : 0000:00:16.0
>>> 605d1c1000-605d1c1fff : mei_me
>>> 605d1c5000-605d1c5fff : 0000:00:14.2
>>> 605d1c6000-605d1c6fff : 0000:00:0d.3
>>> 605d1c7000-605d1c7fff : 0000:00:0d.2
>>> 605d1c8000-605d1c8fff : 0000:00:08.0
>>> 6060000000-607bffffff : PCI Bus 0000:7d
>>> 6060000000-6071ffffff : PCI Bus 0000:7e
>>> 6060000000-6071ffffff : PCI Bus 0000:7f
>>> 6060000000-606fffffff : 0000:7f:00.0
>>> 6070000000-6071ffffff : 0000:7f:00.0
>>>
>>>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Connecting multiple TB3 eGPUs via USB4 hub?'
2026-06-10 22:48 ` Dag B
@ 2026-06-11 4:41 ` Mika Westerberg
2026-06-11 5:28 ` Mika Westerberg
0 siblings, 1 reply; 6+ messages in thread
From: Mika Westerberg @ 2026-06-11 4:41 UTC (permalink / raw)
To: Dag B; +Cc: Bjorn Helgaas, linux-pci, linux-usb, Ilpo Järvinen,
Lukas Wunner
Hi,
On Thu, Jun 11, 2026 at 12:48:40AM +0200, Dag B wrote:
>
> On 6/9/26 14:08, Mika Westerberg wrote:
> > Hi,
> >
> > On Mon, Jun 08, 2026 at 10:26:40AM -0500, Bjorn Helgaas wrote:
> > > [+cc linux-usb (Thunderbolt maintainers), Ilpo, Lukas]
> > >
> > > On Sun, May 24, 2026 at 04:56:56PM +0200, Dag B wrote:
> > > > I am attempting to connect two TB3 enclosures to the same USB4 port via a
> > > > USB4 hub.
> > > >
> > > > I cannot figure out of this is in violation of the TB3, TB4 or USB4 spec.
> > > I'm not aware of a spec issue here.
> Thank you very much Bjorn, slightly more interesting trying to get it to
> work then.
> > It should be fine but typically PCIe resources for one tunneled PCIe root
> > port may not be enough for multiple GPUs. Therefore I suggest to connect
> > them directly to the host USB4 ports without a hub.
>
> That makes perfect sense. Until you run out of physical ports. The entire
> point of this exercise started with trying to connect a 5th 3090 to my fw13
> motherboard. :-D
>
> Hence the USB4 hub. But even with just the hub and two connected GPUs, it
> fails.
Yes most likely because a single GPU takes lots of resources and there is
quite small window reserved per root port for example:
Memory behind bridge: 60000000-6c1fffff [size=194M] [32-bit]
Prefetchable memory behind bridge: 6040000000-605bffffff [size=448M] [32-bit]
Looking at your logs you have all 4 PCIe root ports for tunneling listed
there so I would expect you have 4 USB4/TB ports available as well
(typically the root ports not available for tunneling will not be visible
to the OS).
> For now, I have limited my testing to just the USB4 hub and either one or
> two GPUs.
>
>
> > Second thing is that you have bunch of PCIe related command line parameters
> > that may affect. I suggest removing all of them, and retry. There is hardly
> > any reason to add these - the kernel should be able to handle this by
> > default.
>
> Mhm. I have stripped the command line parameters for some of my tests. It
> absolutely works with nothing extra for a single GPU. And it absolutely did
> not work without command-line params and with 4 GPUs when I started on this
> adventure. But that was around 6.16-6.17.
>
>
> >
> > Then provide full dmesg along with output of 'sudo lspci -vv' so we can
> > look a the resource allocation.
>
> This very quickly becomes a lot of data as I test various things. I put a
> repo with various data up on github.
>
> https://github.com/dagbdagb/usb4_to_tb3_troubleshooting/
There seems to be no dmesg + lspci without the command line parameters? Can
you do this:
1. Remove all the non-default command line parameters.
2. Boot the system up, nothing connected.
3. Plug in the USB4 dock, enable PCIe tunnel (this probably is automatic)
4. Plug in the first eGPU to the dock, enable PCIe tunnel
5. Plug in the second eGPU to the dock, enable PCIe tunnel
From this take full dmesg and output of 'sudo lspci -vv'. At least we can
see how the "default" kernel resource allocation fails.
> If you truly want all this on the mailing list, please let me know.
>
> >
> > > Below it looks like you hot-added the hub. Does it make any
> > > difference if everything is connected before boot?
>
> Yes. With both GPUs connected at boot, none of them will work. With just
> one, it works.
Okay that tells the BIOS does not even try to assign the resources for
both of them.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Connecting multiple TB3 eGPUs via USB4 hub?'
2026-06-11 4:41 ` Mika Westerberg
@ 2026-06-11 5:28 ` Mika Westerberg
0 siblings, 0 replies; 6+ messages in thread
From: Mika Westerberg @ 2026-06-11 5:28 UTC (permalink / raw)
To: Dag B; +Cc: Bjorn Helgaas, linux-pci, linux-usb, Ilpo Järvinen,
Lukas Wunner
On Thu, Jun 11, 2026 at 06:41:14AM +0200, Mika Westerberg wrote:
> Hi,
>
> On Thu, Jun 11, 2026 at 12:48:40AM +0200, Dag B wrote:
> >
> > On 6/9/26 14:08, Mika Westerberg wrote:
> > > Hi,
> > >
> > > On Mon, Jun 08, 2026 at 10:26:40AM -0500, Bjorn Helgaas wrote:
> > > > [+cc linux-usb (Thunderbolt maintainers), Ilpo, Lukas]
> > > >
> > > > On Sun, May 24, 2026 at 04:56:56PM +0200, Dag B wrote:
> > > > > I am attempting to connect two TB3 enclosures to the same USB4 port via a
> > > > > USB4 hub.
> > > > >
> > > > > I cannot figure out of this is in violation of the TB3, TB4 or USB4 spec.
> > > > I'm not aware of a spec issue here.
> > Thank you very much Bjorn, slightly more interesting trying to get it to
> > work then.
> > > It should be fine but typically PCIe resources for one tunneled PCIe root
> > > port may not be enough for multiple GPUs. Therefore I suggest to connect
> > > them directly to the host USB4 ports without a hub.
> >
> > That makes perfect sense. Until you run out of physical ports. The entire
> > point of this exercise started with trying to connect a 5th 3090 to my fw13
> > motherboard. :-D
> >
> > Hence the USB4 hub. But even with just the hub and two connected GPUs, it
> > fails.
>
> Yes most likely because a single GPU takes lots of resources and there is
> quite small window reserved per root port for example:
>
> Memory behind bridge: 60000000-6c1fffff [size=194M] [32-bit]
> Prefetchable memory behind bridge: 6040000000-605bffffff [size=448M] [32-bit]
>
> Looking at your logs you have all 4 PCIe root ports for tunneling listed
> there so I would expect you have 4 USB4/TB ports available as well
> (typically the root ports not available for tunneling will not be visible
> to the OS).
>
> > For now, I have limited my testing to just the USB4 hub and either one or
> > two GPUs.
> >
> >
> > > Second thing is that you have bunch of PCIe related command line parameters
> > > that may affect. I suggest removing all of them, and retry. There is hardly
> > > any reason to add these - the kernel should be able to handle this by
> > > default.
> >
> > Mhm. I have stripped the command line parameters for some of my tests. It
> > absolutely works with nothing extra for a single GPU. And it absolutely did
> > not work without command-line params and with 4 GPUs when I started on this
> > adventure. But that was around 6.16-6.17.
> >
> >
> > >
> > > Then provide full dmesg along with output of 'sudo lspci -vv' so we can
> > > look a the resource allocation.
> >
> > This very quickly becomes a lot of data as I test various things. I put a
> > repo with various data up on github.
> >
> > https://github.com/dagbdagb/usb4_to_tb3_troubleshooting/
>
> There seems to be no dmesg + lspci without the command line parameters? Can
> you do this:
>
> 1. Remove all the non-default command line parameters.
> 2. Boot the system up, nothing connected.
> 3. Plug in the USB4 dock, enable PCIe tunnel (this probably is automatic)
> 4. Plug in the first eGPU to the dock, enable PCIe tunnel
> 5. Plug in the second eGPU to the dock, enable PCIe tunnel
>
> From this take full dmesg and output of 'sudo lspci -vv'. At least we can
> see how the "default" kernel resource allocation fails.
Actually there is dmesg.6+hotplug_egpu_2 and lspci-vv.6+hotplug_egpu_2.
Sorry missed that.
The first GPU seems to fit fine:
[ 24.538295] nvidia 0000:66:00.0: enabling device (0000 -> 0003)
[ 24.539803] nvidia 0000:66:00.0: vgaarb: VGA decodes changed: olddecodes=io+mem,decodes=none:owns=none
[ 24.590905] NVRM: loading NVIDIA UNIX Open Kernel Module for x86_64 610.43.02 Release Build (portage@localhost) Wed Jun 10 19:38:57 -00 2026
But then the second one has not enough resources left, the 55:03.0
downstream port that is used to connect the second GPU has only these left:
I/O behind bridge: b000-bfff [size=4K] [16-bit]
Memory behind bridge: 66e00000-6a2fffff [size=53M] [32-bit]
Prefetchable memory behind bridge: [disabled] [64-bit]
Some BIOSes has an option that you can increase the amount of resources for
the root ports but some vendors hide it.
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2026-06-11 5:28 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-05-24 14:56 Connecting multiple TB3 eGPUs via USB4 hub? Dag B
2026-06-08 15:26 ` Connecting multiple TB3 eGPUs via USB4 hub?' Bjorn Helgaas
2026-06-09 12:08 ` Mika Westerberg
2026-06-10 22:48 ` Dag B
2026-06-11 4:41 ` Mika Westerberg
2026-06-11 5:28 ` Mika Westerberg
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