public inbox for netdev@vger.kernel.org 
 help / color / mirror / Atom feed
From: "Bjørn Mork" <bjorn-yOkvZcmFvRU@public•gmane.org>
To: Ming Lei <ming.lei-Z7WLFzj8eWMS+FvcfC7Uqw@public•gmane.org>
Cc: "David S. Miller" <davem-fT/PcQaiUtIeIZ0/mPfg9Q@public•gmane.org>,
	Greg Kroah-Hartman
	<gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public•gmane.org>,
	Jiri Kosina <jkosina-AlSwsSmVLrQ@public•gmane.org>,
	Alan Stern
	<stern-nwvwT67g6+6dFdvTe/nMLpVzexx5G7lz@public•gmane.org>,
	Oliver Neukum <oneukum-l3A5Bk7waGM@public•gmane.org>,
	netdev-u79uwXL29TY76Z2rM5mHXA@public•gmane.org,
	linux-usb-u79uwXL29TY76Z2rM5mHXA@public•gmane.org,
	linux-input-u79uwXL29TY76Z2rM5mHXA@public•gmane.org
Subject: Re: [PATCH 4/7] usbnet: cdc_mbim: don't recover device if suspend fails in system sleep
Date: Wed, 06 Mar 2013 08:06:10 +0100	[thread overview]
Message-ID: <87k3plnh25.fsf@nemi.mork.no> (raw)
In-Reply-To: <CACVXFVN=i10cVS3RQ7jGrJAfsC+r2t61z7XOVKWMAMqKKELZCg-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> (Ming Lei's message of "Wed, 6 Mar 2013 11:03:40 +0800")

Ming Lei <ming.lei-Z7WLFzj8eWMS+FvcfC7Uqw@public•gmane.org> writes:
> On Wed, Mar 6, 2013 at 10:51 AM, Ming Lei <ming.lei-Z7WLFzj8eWMS+FvcfC7Uqw@public•gmane.org> wrote:
>> On Wed, Mar 6, 2013 at 12:08 AM, Bjørn Mork <bjorn-yOkvZcmFvRU@public•gmane.org> wrote:
>>
>>> I guess proper error handling here require the USB core to see the
>>> interface driver as dead if it fails to suspend on system suspend, and
>>> do forced rebinding on resume.
>>
>> The idea should be fine, but may cause regression of user space, suppose
>> one device with suspend failure can be across suspend-resume cycle and
>> work well before, but it is no longer with your forced rebinding.
>
> Give the potential cost(user space regression) of doing rebind, I think it
> is better to try to recover the device in resume() first, then
> consider rebinding
> as the last straw.  In fact, I am also wondering if resume() can't recover one
> device but probe() can, maybe we can always let resume() recover the
> device which experienced suspend failure.

Yes, sure. Drivers wanting to do this, anticipating typical errors, can
still return 0 from suspend and do whatever they want in resume.

My proposal is to make the USB core properly deal with drivers returning
an error from suspend, and also document the fact that a driver should
always return 0 on system suspend unless it really want forced unbinding
on suspend errors.

> I remember that some guys went against rebinding during system sleep before
> in the firmware loading discussion.

Yes, that is probably relevant. I'll look it up.  Thanks for the
pointer.


Bjørn
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public•gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

  parent reply	other threads:[~2013-03-06  7:06 UTC|newest]

Thread overview: 33+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-03-05  4:01 [PATCH 0/7] USB: don't recover device if suspend fails in system sleep Ming Lei
2013-03-05  4:01 ` [PATCH 1/7] USB: adds comment on suspend callback Ming Lei
2013-03-05 13:16   ` Ming Lei
     [not found] ` <1362456103-24956-1-git-send-email-ming.lei-Z7WLFzj8eWMS+FvcfC7Uqw@public.gmane.org>
2013-03-05  4:01   ` [PATCH 2/7] USB: serial: handle suspend failure path correctly Ming Lei
2013-03-05  4:01 ` [PATCH 3/7] USBHID: don't recover device if suspend fails in system sleep Ming Lei
2013-03-05  4:01 ` [PATCH 4/7] usbnet: cdc_mbim: " Ming Lei
     [not found]   ` <1362456103-24956-5-git-send-email-ming.lei-Z7WLFzj8eWMS+FvcfC7Uqw@public.gmane.org>
2013-03-05  7:09     ` Bjørn Mork
2013-03-05 11:07       ` Ming Lei
2013-03-05 13:46         ` Bjørn Mork
2013-03-05 14:50           ` Ming Lei
2013-03-05 15:03             ` Bjørn Mork
2013-03-05 15:29               ` Ming Lei
2013-03-05 16:08                 ` Bjørn Mork
     [not found]                   ` <87wqtlommw.fsf-lbf33ChDnrE/G1V5fR+Y7Q@public.gmane.org>
2013-03-05 16:54                     ` Alan Stern
2013-03-05 17:35                       ` Bjørn Mork
2013-03-06  2:51                   ` Ming Lei
2013-03-06  3:03                     ` Ming Lei
     [not found]                       ` <CACVXFVN=i10cVS3RQ7jGrJAfsC+r2t61z7XOVKWMAMqKKELZCg-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-03-06  7:06                         ` Bjørn Mork [this message]
2013-03-06  7:50                           ` Ming Lei
2013-03-06  8:32                             ` Bjørn Mork
2013-03-05  4:01 ` [PATCH 5/7] usbnet: smsc95xx: " Ming Lei
2013-03-05  4:01 ` [PATCH 6/7] usbnet: smsc75xx: " Ming Lei
2013-03-05  4:01 ` [PATCH 7/7] usbnet: qmi_wwan: " Ming Lei
     [not found]   ` <1362456103-24956-8-git-send-email-ming.lei-Z7WLFzj8eWMS+FvcfC7Uqw@public.gmane.org>
2013-03-05  7:09     ` Bjørn Mork
2013-03-05 12:27       ` Ming Lei
2013-03-05  5:14 ` [PATCH 0/7] USB: " Ming Lei
2013-03-05  7:03 ` Bjørn Mork
2013-03-05 10:55   ` Ming Lei
2013-03-05 12:50     ` Oliver Neukum
     [not found]       ` <3703451.5FViJ58GpZ-7ztolUikljGernLeA6q8OA@public.gmane.org>
2013-03-05 13:08         ` Ming Lei
2013-03-05 13:28           ` Oliver Neukum
2013-03-05 14:03             ` Ming Lei
2013-03-05 13:18     ` Bjørn Mork

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=87k3plnh25.fsf@nemi.mork.no \
    --to=bjorn-yokvzcmfvru@public$(echo .)gmane.org \
    --cc=davem-fT/PcQaiUtIeIZ0/mPfg9Q@public$(echo .)gmane.org \
    --cc=gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public$(echo .)gmane.org \
    --cc=jkosina-AlSwsSmVLrQ@public$(echo .)gmane.org \
    --cc=linux-input-u79uwXL29TY76Z2rM5mHXA@public$(echo .)gmane.org \
    --cc=linux-usb-u79uwXL29TY76Z2rM5mHXA@public$(echo .)gmane.org \
    --cc=ming.lei-Z7WLFzj8eWMS+FvcfC7Uqw@public$(echo .)gmane.org \
    --cc=netdev-u79uwXL29TY76Z2rM5mHXA@public$(echo .)gmane.org \
    --cc=oneukum-l3A5Bk7waGM@public$(echo .)gmane.org \
    --cc=stern-nwvwT67g6+6dFdvTe/nMLpVzexx5G7lz@public$(echo .)gmane.org \
    /path/to/YOUR_REPLY

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