Hi All, I'm in the process of updating the kernel version used on our products from 4.4 -> 5.1. We have one product that uses a Kirkwood CPU, IDT PCI bridge and Marvell Switch ASIC. The Switch ASIC presents as multiple PCI devices. The hardware setup looks like this __________ [ Kirkwood ] --- [ IDT 5T5 ] ---+--- | | +--- | Switch | +--- | | +--- |__________| On the 4.4 based kernel things are fine [root@awplus flash]# lspci -t -[0000:00]---01.0-[01-06]----00.0-[02-06]--+-02.0-[03]----00.0 +-03.0-[04]----00.0 +-04.0-[05]----00.0 \-05.0-[06]----00.0 But on the 5.1 based kernel things get a little weird [root@awplus flash]# lspci -t -[0000:00]---01.0-[01-06]--+-00.0-[02-06]-- +-01.0 +-02.0-[02-06]-- +-03.0-[02-06]-- +-04.0-[02-06]-- +-05.0-[02-06]-- +-06.0-[02-06]-- +-07.0-[02-06]-- +-08.0-[02-06]-- +-09.0-[02-06]-- +-0a.0-[02-06]-- +-0b.0-[02-06]-- +-0c.0-[02-06]-- +-0d.0-[02-06]-- +-0e.0-[02-06]-- +-0f.0-[02-06]-- +-10.0-[02-06]-- +-11.0-[02-06]-- +-12.0-[02-06]-- +-13.0-[02-06]-- +-14.0-[02-06]-- +-15.0-[02-06]-- +-16.0-[02-06]-- +-17.0-[02-06]-- +-18.0-[02-06]-- +-19.0-[02-06]-- +-1a.0-[02-06]-- +-1b.0-[02-06]-- +-1c.0-[02-06]-- +-1d.0-[02-06]-- +-1e.0-[02-06]-- \-1f.0-[02-06]--+-02.0-[03]----00.0 +-03.0-[04]----00.0 +-04.0-[05]----00.0 \-05.0-[06]----00.0 I'll start bisecting to see where things started going wrong. I just wondered if this rings any bells for anyone. The startup output also seems to be quite unhappy Detected board: alliedtelesis,SBx81GC40 Booting into Linux kernel ... ** 143 printk messages dropped ** pci 0000:01:19.0: PME# supported from D0 D3hot D3cold pci 0000:01:1a.0: [111d:803c] type 01 class 0x060400 pci 0000:01:1a.0: PME# supported from D0 D3hot D3cold pci 0000:01:1b.0: [111d:803c] type 01 class 0x060400 pci 0000:01:1b.0: PME# supported from D0 D3hot D3cold pci 0000:01:1c.0: [111d:803c] type 01 class 0x060400 pci 0000:01:1c.0: PME# supported from D0 D3hot D3cold pci 0000:01:1d.0: [111d:803c] type 01 class 0x060400 pci 0000:01:1d.0: PME# supported from D0 D3hot D3cold pci 0000:01:1e.0: [111d:803c] type 01 class 0x060400 pci 0000:01:1e.0: PME# supported from D0 D3hot D3cold pci 0000:01:1f.0: [111d:803c] type 01 class 0x060400 pci 0000:01:1f.0: PME# supported from D0 D3hot D3cold PCI: bus1: Fast back to back transfers disabled pci 0000:01:00.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:02.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:03.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:04.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:05.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:06.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:07.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:08.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:09.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:0a.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:0b.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:0c.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:0d.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:0e.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:0f.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:10.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:11.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:12.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:13.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:14.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:15.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:16.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:17.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:18.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:19.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:1a.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:1b.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:1c.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:1d.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:1e.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:01:1f.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:02:02.0: [111d:803c] type 01 class 0x060400 pci 0000:02:02.0: enabling Extended Tags pci 0000:02:02.0: PME# supported from D0 D3hot D3cold pci 0000:02:03.0: [111d:803c] type 01 class 0x060400 pci 0000:02:03.0: enabling Extended Tags pci 0000:02:03.0: PME# supported from D0 D3hot D3cold pci 0000:02:04.0: [111d:803c] type 01 class 0x060400 pci 0000:02:04.0: enabling Extended Tags pci 0000:02:04.0: PME# supported from D0 D3hot D3cold pci 0000:02:05.0: [111d:803c] type 01 class 0x060400 pci 0000:02:05.0: enabling Extended Tags pci 0000:02:05.0: PME# supported from D0 D3hot D3cold PCI: bus2: Fast back to back transfers disabled pci 0000:02:02.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:02:03.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:02:04.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:02:05.0: bridge configuration invalid ([bus 00-00]), reconfiguring pci 0000:03:00.0: [11ab:e023] type 00 class 0x058000 pci 0000:03:00.0: reg 0x10: [mem 0xd0000000-0xd00fffff 64bit pref] pci 0000:03:00.0: reg 0x18: [mem 0x00000000-0x03ffffff 64bit] PCI: bus3: Fast back to back transfers disabled pci_bus 0000:03: busn_res: [bus 03-ff] end is updated to 03 pci 0000:04:00.0: [11ab:e023] type 00 class 0x058000 pci 0000:04:00.0: reg 0x10: [mem 0xd0000000-0xd00fffff 64bit pref] pci 0000:04:00.0: reg 0x18: [mem 0x00000000-0x03ffffff 64bit] PCI: bus4: Fast back to back transfers disabled pci_bus 0000:04: busn_res: [bus 04-ff] end is updated to 04 pci 0000:05:00.0: [11ab:e023] type 00 class 0x058000 pci 0000:05:00.0: reg 0x10: [mem 0xd0000000-0xd00fffff 64bit pref] pci 0000:05:00.0: reg 0x18: [mem 0x00000000-0x03ffffff 64bit] PCI: bus5: Fast back to back transfers disabled pci_bus 0000:05: busn_res: [bus 05-ff] end is updated to 05 pci 0000:06:00.0: [11ab:e023] type 00 class 0x058000 pci 0000:06:00.0: reg 0x10: [mem 0xd0000000-0xd00fffff 64bit pref] pci 0000:06:00.0: reg 0x18: [mem 0x00000000-0x03ffffff 64bit] PCI: bus6: Fast back to back transfers disabled pci_bus 0000:06: busn_res: [bus 06-ff] end is updated to 06 pci_bus 0000:02: busn_res: [bus 02-ff] end is updated to 06 pci_bus 0000:01: busn_res: [bus 01-ff] end is updated to 06 pci 0000:00:01.0: BAR 8: no space for [mem size 0x1c000000] pci 0000:00:01.0: BAR 8: failed to assign [mem size 0x1c000000] pci 0000:00:01.0: BAR 6: assigned [mem 0xe0000000-0xe00007ff pref] pci 0000:01:01.0: BAR 2: no space for [mem size 0x08000000] pci 0000:01:01.0: BAR 2: failed to assign [mem size 0x08000000] pci 0000:01:00.0: BAR 8: no space for [mem size 0x10000000] pci 0000:01:00.0: BAR 8: failed to assign [mem size 0x10000000] pci 0000:01:00.0: BAR 9: no space for [mem size 0x00400000 64bit pref] pci 0000:01:00.0: BAR 9: failed to assign [mem size 0x00400000 64bit pref] pci 0000:01:01.0: BAR 0: no space for [mem size 0x00100000 64bit pref] pci 0000:01:01.0: BAR 0: failed to assign [mem size 0x00100000 64bit pref] pci 0000:02:02.0: BAR 8: no space for [mem size 0x04000000] pci 0000:02:02.0: BAR 8: failed to assign [mem size 0x04000000] pci 0000:02:03.0: BAR 8: no space for [mem size 0x04000000] pci 0000:02:03.0: BAR 8: failed to assign [mem size 0x04000000] pci 0000:02:04.0: BAR 8: no space for [mem size 0x04000000] pci 0000:02:04.0: BAR 8: failed to assign [mem size 0x04000000] pci 0000:02:05.0: BAR 8: no space for [mem size 0x04000000] pci 0000:02:05.0: BAR 8: failed to assign [mem size 0x04000000] pci 0000:02:02.0: BAR 9: no space for [mem size 0x00100000 64bit pref] pci 0000:02:02.0: BAR 9: failed to assign [mem size 0x00100000 64bit pref] pci 0000:02:03.0: BAR 9: no space for [mem size 0x00100000 64bit pref] pci 0000:02:03.0: BAR 9: failed to assign [mem size 0x00100000 64bit pref] pci 0000:02:04.0: BAR 9: no space for [mem size 0x00100000 64bit pref] pci 0000:02:04.0: BAR 9: failed to assign [mem size 0x00100000 64bit pref] pci 0000:02:05.0: BAR 9: no space for [mem size 0x00100000 64bit pref] pci 0000:02:05.0: BAR 9: failed to assign [mem size 0x00100000 64bit pref] pci 0000:03:00.0: BAR 2: no space for [mem size 0x04000000 64bit] pci 0000:03:00.0: BAR 2: failed to assign [mem size 0x04000000 64bit] pci 0000:03:00.0: BAR 0: no space for [mem size 0x00100000 64bit pref] pci 0000:03:00.0: BAR 0: failed to assign [mem size 0x00100000 64bit pref] pci 0000:02:02.0: PCI bridge to [bus 03] pci 0000:04:00.0: BAR 2: no space for [mem size 0x04000000 64bit] pci 0000:04:00.0: BAR 2: failed to assign [mem size 0x04000000 64bit] pci 0000:04:00.0: BAR 0: no space for [mem size 0x00100000 64bit pref] pci 0000:04:00.0: BAR 0: failed to assign [mem size 0x00100000 64bit pref] pci 0000:02:03.0: PCI bridge to [bus 04] pci 0000:05:00.0: BAR 2: no space for [mem size 0x04000000 64bit] pci 0000:05:00.0: BAR 2: failed to assign [mem size 0x04000000 64bit] pci 0000:05:00.0: BAR 0: no space for [mem size 0x00100000 64bit pref] pci 0000:05:00.0: BAR 0: failed to assign [mem size 0x00100000 64bit pref] pci 0000:02:04.0: PCI bridge to [bus 05] pci 0000:06:00.0: BAR 2: no space for [mem size 0x04000000 64bit] pci 0000:06:00.0: BAR 2: failed to assign [mem size 0x04000000 64bit] pci 0000:06:00.0: BAR 0: no space for [mem size 0x00100000 64bit pref] pci 0000:06:00.0: BAR 0: failed to assign [mem size 0x00100000 64bit pref] pci 0000:02:05.0: PCI bridge to [bus 06] pci 0000:01:00.0: PCI bridge to [bus 02-06] pci 0000:00:01.0: PCI bridge to [bus 01-06]