From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C40CDC4360F for ; Tue, 2 Apr 2019 14:29:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9F3A820857 for ; Tue, 2 Apr 2019 14:29:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731870AbfDBO3w (ORCPT ); Tue, 2 Apr 2019 10:29:52 -0400 Received: from iolanthe.rowland.org ([192.131.102.54]:43252 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1731667AbfDBO3v (ORCPT ); Tue, 2 Apr 2019 10:29:51 -0400 Received: (qmail 3078 invoked by uid 2102); 2 Apr 2019 10:29:49 -0400 Received: from localhost (sendmail-bs@127.0.0.1) by localhost with SMTP; 2 Apr 2019 10:29:49 -0400 Date: Tue, 2 Apr 2019 10:29:49 -0400 (EDT) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Bjorn Helgaas cc: Jesse Hathaway , Ingo Molnar , Peter Zijlstra , , , Mathias Nyman , Greg Kroah-Hartman , Subject: Re: Regression causes a hang on boot with a Comtrol PCI card In-Reply-To: <20190401211353.GA7263@google.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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@mail.gmail.com > > 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