Issue resolved - see below . > On Mar 31, 2020, at 9:17 AM, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > > On Mon, 30 Mar 2020, John Donnelly wrote: > >> The debug method produces the following: >> >> iommu=on ( no BCM is discovered ) >> >> [ 9.911027] hub 4-0:1.0: state 7 ports 6 chg 0000 evt 0000 >> [ 9.923028] usb 3-3: new high-speed USB device number 2 using xhci_hcd >> [ 9.950106] In hub_port_connect .. init >> [ 9.963879] usb 3-3: udev 2, busnum 3, minor = 257 >> [ 9.963882] usb 3-3: New USB device found, idVendor=0424, >> idProduct=2660, bcdDevice= 8.01 >> [ 9.978980] usb 3-3: New USB device strings: Mfr=0, Product=0, >> SerialNumber=0 >> [ 9.994524] usb 3-3: usb_probe_device >> [ 9.994527] usb 3-3: configuration #1 chosen from 1 choice >> [ 9.994790] usb 3-3: adding 3-3:1.0 (config #1, interface 0) >> [ 9.994826] hub 3-3:1.0: usb_probe_interface >> [ 9.994828] hub 3-3:1.0: usb_probe_interface - got id >> [ 9.994831] hub 3-3:1.0: USB hub found >> [ 10.008224] hub 3-3:1.0: 2 ports detected >> [ 10.021669] hub 3-3:1.0: compound device; port removable status: FR >> [ 10.021671] hub 3-3:1.0: individual port power switching >> [ 10.021672] hub 3-3:1.0: individual port over-current protection >> [ 10.021674] hub 3-3:1.0: Single TT >> [ 10.021676] hub 3-3:1.0: TT requires at most 8 FS bit times (666 ns) >> [ 10.021678] hub 3-3:1.0: power on to power good time: 100ms >> [ 10.021753] hub 3-3:1.0: local power source is good >> [ 10.021872] hub 3-3:1.0: enabling power on all ports >> [ 10.022120] hub 2-1:1.0: state 7 ports 8 chg 0000 evt 0000 >> [ 10.127115] hub 3-3:1.0: state 7 ports 2 chg 0000 evt 0000 >> [ 10.327902] i8042: Can't read CTR while initializing i8042 >> >> >> Produces this configuration without the BCM devices : >> >> >> lsusb -t >> /: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/6p, 5000M >> /: Bus 03.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/15p, 480M >> |__ Port 3: Dev 2, If 0, Class=Hub, Driver=hub/2p, 480M >> /: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/2p, 480M >> |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/8p, 480M >> /: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/2p, 480M >> |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/6p, 480M >> >> >> >> BCM is discovered intel_iommu=off : >> >> >> [ 8.947539] usb 4-3: adding 4-3:1.0 (config #1, interface 0) >> [ 8.947569] hub 4-3:1.0: usb_probe_interface >> [ 8.947571] hub 4-3:1.0: usb_probe_interface - got id >> [ 8.947574] hub 4-3:1.0: USB hub found >> [ 8.960496] usb 3-1: skipped 1 descriptor after interface >> [ 8.960499] usb 3-1: skipped 1 descriptor after interface >> [ 8.960562] hub 4-3:1.0: 2 ports detected >> [ 8.974067] usb 3-1: default language 0x0409 >> [ 8.974074] hub 4-3:1.0: compound device; port removable status: FR >> [ 8.974075] hub 4-3:1.0: individual port power switching >> [ 8.974077] hub 4-3:1.0: individual port over-current protection >> [ 8.974079] hub 4-3:1.0: Single TT >> [ 8.974081] hub 4-3:1.0: TT requires at most 8 FS bit times (666 ns) >> [ 8.974083] hub 4-3:1.0: power on to power good time: 100ms >> [ 8.974157] hub 4-3:1.0: local power source is good >> [ 8.974259] hub 4-3:1.0: enabling power on all ports >> [ 8.979469] usb 3-1: udev 2, busnum 3, minor = 257 >> [ 8.979473] usb 3-1: New USB device found, idVendor=03f0, >> idProduct=7029, bcdDevice= 0.02 >> [ 8.994797] usb 3-1: New USB device strings: Mfr=1, Product=2, >> SerialNumber=0 >> [ 9.010633] usb 3-1: Product: Virtual Keyboard >> [ 9.024416] usb 3-1: Manufacturer: BMC >> [ 9.037858] usb 3-1: usb_probe_device >> [ 9.037860] usb 3-1: configuration #1 chosen from 1 choice >> [ 9.039418] usb 3-1: adding 3-1:1.0 (config #1, interface 0) >> [ 9.041507] usb 3-1: adding 3-1:1.1 (config #1, interface 1) >> [ 9.076272] hub 4-3:1.0: state 7 ports 2 chg 0000 evt 0000 >> >> I am not accustomed to looking the USB Bus.port.dev mappings , obviously >> with BCM discovered there are 05 Bus instead of 4 . >> >> /: Bus 05.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/6p, 5000M >> /: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/15p, 480M >> |__ Port 3: Dev 2, If 0, Class=Hub, Driver=hub/2p, 480M >> /: Bus 03.Port 1: Dev 1, Class=root_hub, Driver=uhci_hcd/2p, 12M >> |__ Port 1: Dev 2, If 0, Class=Human Interface Device, >> Driver=usbhid, 12M >> |__ Port 1: Dev 2, If 1, Class=Human Interface Device, >> Driver=usbhid, 12M >> /: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/2p, 480M >> |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/8p, 480M >> /: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/2p, 480M >> |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/6p, 480M > > It seems pretty clear that your system (or at least the BMC part) > doesn't work as intended when the iommu is turned on. > >> Here are the pci mappings: >> >> [ 6.381615] input: BMC Virtual Keyboard as >> /devices/pci0000:00/0000:00:1c.2/0000:01:00.4/usb3/3-1/3-1:1.0/0003:03F0:7029.0001/input/input1 >> [ 6.463638] hid-generic 0003:03F0:7029.0001: input,hidraw0: USB HID >> v1.01 Keyboard [BMC Virtual Keyboard ] on usb-0000:01:00.4-1/input0 >> [ 6.496589] input: BMC Virtual Keyboard as >> /devices/pci0000:00/0000:00:1c.2/0000:01:00.4/usb3/3-1/3-1:1.1/0003:03F0:7029.0002/input/input2 >> [ 6.529449] hid-generic 0003:03F0:7029.0002: input,hidraw1: USB HID >> v1.01 Mouse [BMC Virtual Keyboard ] on usb-0000:01:00.4-1/input1 >> [ 6.563139] usbcore: registered new interface driver usbhid >> [ 6.580222] usbhid: USB HID core driver > > I don't know why you call these "pci mappings". They have nothing to > do with PCI, and the last two lines don't talk about mappings at all. > >> The last activity done seen on both traces is : >> >> " enabling power on all ports " > > Why do you say this is the last activity seen on both traces? In both > of the log extracts you included above there are plenty of lines > following those "enabling power" messages. > >> Is this when the BCM discovery is suppose to occur ? In the function >> example is when the udev appears: >> >> usb 3-1: udev 2, busnum 3, minor = 257 > > The BCM discovery is supposed to occur at the time you see it in the > second log extract above. > > One thing I didn't notice before: With iommu=off, you get an entire new > USB host controller and bus. It is called bus 3, and neither it nor > the 3-1 device (mouse and keyboard) is present when iommu=on. In > fact, by comparing the listings you can see that buses 4 and 5 (with > iommu=off) are really the same as buses 3 and 4 (with iommu=on). > > I'd say that your BMC does not work with iommu=on, and it is that > failure which causes these extra devices not to be discovered. In > fact, they appear not be real physical devices at all, but rather > virtual devices created by the BMC firmware. > > If you want to find out why the BMC doesn't work with iommu=on, you > should ask the company that manufactured your computer's motherboard. > They are probably the only people who know the answer. > > Alan Stern > This issue has been resolved in 5.6.0.rc1 ( and 5.6.0.rc6 ) with commit : 9235cb13d7d1 iommu/vt-d: Allow devices with RMRRs to use identity domain When I applied this to 5.4.17 release I get the iLO USB hub properly enumerated and the corresponding keyboard and mouse ( when iommu=pt ) [ 8.798927] ohci_hcd: USB 1.1 'Open' Host Controller (OHCI) Driver [ 8.812350] ohci-pci: OHCI PCI platform driver [ 8.824135] uhci_hcd: USB Universal Host Controller Interface driver [ 8.837210] uhci_hcd 0000:01:00.4: UHCI Host Controller [ 8.850133] uhci_hcd 0000:01:00.4: new USB bus registered, assigned bus number 3 [ 8.863092] uhci_hcd 0000:01:00.4: detected 8 ports [ 8.875997] uhci_hcd 0000:01:00.4: port count misdetected? forcing to 2 ports [ 8.889987] uhci_hcd 0000:01:00.4: supports USB remote wakeup [ 8.890014] uhci_hcd 0000:01:00.4: irq 19, io base 0x00001300 [ 8.903367] uhci_hcd 0000:01:00.4: DMAR: Setting identity map [0x791dc000 - 0x791ddfff] [ 8.916824] uhci_hcd 0000:01:00.4: DMAR: Setting identity map [0x791cb000 - 0x791dbfff] [ 8.930057] uhci_hcd 0000:01:00.4: DMAR: Setting identity map [0x791de000 - 0x791f3fff] [ 8.943069] uhci_hcd 0000:01:00.4: DMAR: Setting identity map [0x791f4000 - 0x791f7fff] lsusb -t /: Bus 05.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/6p, 5000M /: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/15p, 480M |__ Port 3: Dev 2, If 0, Class=Hub, Driver=hub/2p, 480M /: Bus 03.Port 1: Dev 1, Class=root_hub, Driver=uhci_hcd/2p, 12M |__ Port 1: Dev 2, If 0, Class=Human Interface Device, Driver=usbhid, 12M |__ Port 1: Dev 2, If 1, Class=Human Interface Device, Driver=usbhid, 12M /: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/2p, 480M |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/8p, 480M /: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/2p, 480M |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/6p, 480M In researching this regression, I identified another defect on the HP servers that exists in both 5.4.17 and 5.6.0.rc6 that the USB hub is not functional when iommu=off . https://bugzilla.kernel.org/show_bug.cgi?id=207147
