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Date:   Wed, 24 Apr 2019 10:20:45 -0400 (EDT)
From:   Alan Stern <stern@rowland.harvard.edu>
To:     Jesse Hathaway <jesse@mbuki-mvuki.org>
cc:     Bjorn Helgaas <helgaas@kernel.org>, Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        <linux-kernel@vger.kernel.org>, <linux-pci@vger.kernel.org>,
        Mathias Nyman <mathias.nyman@intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        <linux-usb@vger.kernel.org>
Subject: Re: Regression causes a hang on boot with a Comtrol PCI card
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Message-ID: <Pine.LNX.4.44L0.1904241020110.1443-100000@iolanthe.rowland.org>
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On Tue, 23 Apr 2019, Jesse Hathaway wrote:

> On Tue, Apr 16, 2019 at 10:00 AM Alan Stern <stern@rowland.harvard.edu> wrote:
> > Whatever the source of the problem, I don't think you're going to find
> > it by looking at the USB code.  Perhaps the early initialization of the
> > functions that _are_ present on the Comtrol card somehow messes up
> > other parts of the system.
> 
> Thanks for all you help Alan,
> 
> I think at this point my Linux kernel debugging knowledge has run
> aground. I would
> love to crack this nut, but I doubt that will be possible with my
> current knowledge base.
> For now I am going to run the patched kernel even if I don't
> understand precisely why
> they prevent the box from hanging on boot when the Comtrol card is present.

Okay, that's understandable.  Sorry I couldn't do more to help.

Alan Stern