linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Matthew Garrett <mjg59@srcf.ucam.org>
To: Alan Stern <stern@rowland.harvard.edu>
Cc: Anssi Hannula <anssi.hannula@iki.fi>,
	Oliver Neukum <oliver@neukum.org>,
	dvomlehn@cisco.com, gregkh@suse.de, linux-usb@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [REGRESSION] "USB: use kfifo to buffer usb-generic serial writes" causes gobi_loader to hang
Date: Mon, 22 Feb 2010 19:14:32 +0000	[thread overview]
Message-ID: <20100222191432.GA27418@srcf.ucam.org> (raw)
In-Reply-To: <Pine.LNX.4.44L0.1002221408200.1251-100000@iolanthe.rowland.org>

On Mon, Feb 22, 2010 at 02:10:33PM -0500, Alan Stern wrote:
> On Mon, 22 Feb 2010, Anssi Hannula wrote:
> > Does this mean a tty interface is ill-suited for the microcode upload, and 
> > instead qcserial should use the kernel's generic microcode upload mechanism or 
> > the userspace should use libusb to do it?
> 
> I don't know.  Didn't the old successful code use a tty interface?

Yes. The kfifo changes have caused some sort of alteration in behaviour.

> > Any idea what could be causing the hang, then?
> 
> No idea, unless it's the device.

Once the device hangs, it then tends to refuse any input until power 
cycled. So it's clearly getting into some sort of undefined state, 
though whether that's because it only gets sent half of its firmware 
(ie, the hang occurs and as a result the hardware dies) or whether it's 
causing the hang by dying is unclear.

-- 
Matthew Garrett | mjg59@srcf.ucam.org

  reply	other threads:[~2010-02-22 19:14 UTC|newest]

Thread overview: 56+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-01-17  2:55 [REGRESSION] "USB: use kfifo to buffer usb-generic serial writes" causes gobi_loader to hang Matthew Garrett
2010-01-17  8:13 ` Marcel Holtmann
2010-01-17  9:14 ` Oliver Neukum
2010-01-18  1:58   ` Matthew Garrett
2010-01-18 17:25     ` Oliver Neukum
2010-01-18 20:14       ` Matthew Garrett
2010-01-19 13:20         ` Oliver Neukum
2010-01-19 13:29           ` Alan Cox
2010-01-19 13:57             ` Oliver Neukum
2010-01-19 14:21               ` Alan Cox
2010-01-19 15:15                 ` Oliver Neukum
2010-01-19 14:26               ` Alan Cox
2010-01-19 15:25                 ` Johan Hovold
2010-01-19 15:52                   ` Johan Hovold
2010-01-19 16:27                   ` Alan Cox
2010-01-19 18:44                     ` Oliver Neukum
2010-01-19 19:45                       ` Johan Hovold
2010-01-28 17:45           ` Greg KH
2010-01-28 18:40             ` Oliver Neukum
2010-01-28 22:32               ` Greg KH
2010-02-03 16:46           ` Matthew Garrett
2010-02-03 17:21             ` Oliver Neukum
2010-02-03 22:37               ` Matthew Garrett
2010-02-03 22:58                 ` Oliver Neukum
2010-02-05 19:58                   ` Matthew Garrett
2010-02-05 21:35                     ` Matthew Garrett
2010-02-08 19:00                       ` Oliver Neukum
2010-02-05 21:59                     ` Oliver Neukum
2010-02-13  2:09                       ` Anssi Hannula
2010-02-13  2:50                         ` Alan Stern
2010-02-13  7:11                           ` Oliver Neukum
2010-02-13 13:35                             ` Anssi Hannula
2010-02-13 19:01                               ` Anssi Hannula
2010-02-15 13:08                                 ` Oliver Neukum
2010-02-20 16:03                                   ` Anssi Hannula
2010-02-20 18:19                                     ` Oliver Neukum
2010-02-21 21:28                                       ` Alan Stern
2010-02-21 21:42                                         ` Anssi Hannula
2010-02-21 22:12                                           ` Oliver Neukum
2010-02-21 23:06                                             ` Anssi Hannula
2010-02-21 23:13                                               ` Anssi Hannula
2010-02-21 23:21                                                 ` Anssi Hannula
2010-02-22 15:28                                                   ` Alan Stern
2010-02-22 18:35                                                     ` Anssi Hannula
2010-02-22 19:10                                                       ` Alan Stern
2010-02-22 19:14                                                         ` Matthew Garrett [this message]
2010-02-22 20:12                                                           ` Alan Stern
2010-02-24  2:33                                                             ` Anssi Hannula
2010-02-22 19:24                                                         ` Anssi Hannula
2010-02-22 20:10                                                           ` Alan Stern
2010-02-22 21:24                                                           ` Alan Cox
2010-02-22 21:23                                                             ` Matthew Garrett
2010-02-22 23:26                                                       ` Oliver Neukum
2010-02-23  1:55                                                         ` Anssi Hannula
2010-02-21 22:09                                         ` Oliver Neukum
2010-02-21 21:37                                       ` Anssi Hannula

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20100222191432.GA27418@srcf.ucam.org \
    --to=mjg59@srcf.ucam.org \
    --cc=anssi.hannula@iki.fi \
    --cc=dvomlehn@cisco.com \
    --cc=gregkh@suse.de \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-usb@vger.kernel.org \
    --cc=oliver@neukum.org \
    --cc=stern@rowland.harvard.edu \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).