On Tue, 2 Apr 2019, Mathias Nyman wrote: > On 2.4.2019 17.29, Alan Stern wrote: > > On Mon, 1 Apr 2019, Bjorn Helgaas wrote: > > > >> [+cc Mathias, Greg, Alan, linux-usb] > >> > >> Beginning of thread: https://lore.kernel.org/linux-pci/CANSNSoWiKd98Dt1N2sSjP9Af8zk1NPV-=3P4VLtFs_cSQG4RUg@xxxxxxxxxxxxxx > >> > >> Synopsis: v5.0 hangs at boot unless the following commits are reverted: > >> > >> 1302fcf0d03e ("PCI: Configure *all* devices, not just hot-added ones") > >> 1c3c5eab1715 ("sched/core: Enable might_sleep() and smp_processor_id() checks early") > >> > >> The hang appears to be in quirk_usb_early_handoff(). With > >> "initcall_debug", we see the call but not the completion: > >> > >> On Fri, Mar 22, 2019 at 03:02:11PM -0500, Jesse Hathaway wrote: > >>>> So apparently the hang happens while we're running the "final" PCI > >>>> fixups. This happens after all the rest of PCI is initialized. > >>>> > >>>> Can you boot v5.0 vanilla with "initcall_debug"? Maybe we can narrow > >>>> it down to a specific quirk. > >>> > >>> yup, added the "initcall_debug" output to the ticket: > >>> https://bugzilla.kernel.org/show_bug.cgi?id=202927, here is the tail end > >>> > >>> [ 14.896337] NET: Registered protocol family 1 > >>> [ 14.901314] initcall af_unix_init+0x0/0x4e returned 0 after 4866 usecs > >>> [ 14.908694] calling ipv6_offload_init+0x0/0x7f @ 1 > >>> [ 14.914238] initcall ipv6_offload_init+0x0/0x7f returned 0 after 1 usecs > >>> [ 14.921821] calling vlan_offload_init+0x0/0x20 @ 1 > >>> [ 14.927365] initcall vlan_offload_init+0x0/0x20 returned 0 after 0 usecs > >>> [ 14.934948] calling pci_apply_final_quirks+0x0/0x126 @ 1 > >>> [ 14.941106] pci 0000:00:1a.0: calling quirk_usb_early_handoff+0x0/0x6a0 @ 1 > >>> > >>> thanks, Jesse Hathaway > > > > Most likely the problem occurs somewhere inside > > quirk_usb_handoff_xhci(). Can Jesse add debugging statements to that > > routine in order to pin down exactly where the problem lies? > > > > Alan Stern > > > > lspci log from bugzilla shows 0000:00:1a.0 is a EHCI device, > so probably woth adding debugging to quirk_usb_disable_ehci() as well > > 00:1a.0 USB controller: Intel Corporation C610/X99 series chipset USB Enhanced Host Controller #2 (rev 05) (prog-if 20 [EHCI]) Oops! Quite right, my mistake. After all these years, I ought to remember that Intel puts their motherboards' EHCI and UHCI controllers at PCI addresses 00:1a and 00:1d. Alan Stern
