Linux Input/HID development
 help / color / mirror / Atom feed
From: Oliver Neukum <oliver-GvhC2dPhHPQdnm+yROfE0A@public.gmane.org>
To: Dmitry Torokhov
	<dmitry.torokhov-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Cc: linux-input-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	will-ffEBwZeNOFERmelmmXo44Q@public.gmane.org
Subject: Re: [rft]powermate runtime pm
Date: Fri, 4 Jul 2008 00:13:53 +0200	[thread overview]
Message-ID: <200807040013.54237.oliver@neukum.org> (raw)
In-Reply-To: <200807040008.50174.oliver-GvhC2dPhHPQdnm+yROfE0A@public.gmane.org>

Am Freitag 04 Juli 2008 00:08:49 schrieb Oliver Neukum:
> Mutual exclusion is a very good idea. And telling input devices that
> they are open is also a good idea. But this will be difficult, as open()
> will almost certainly wish to do as memory allocations can trigger
> an autoresume.

Sorry, it is late.

Again, in clear language.

You will face a deadlock problem, as open can call into resume,
due to
a) usb_autopm_get_interface()
b) any memory allocation that triggers autoresumption of another
    interface of the same device

	Regards
		Oliver

--
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:[~2008-07-03 22:13 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-07-03 15:53 [rft]powermate runtime pm Oliver Neukum
     [not found] ` <200807031753.16960.oliver-GvhC2dPhHPQdnm+yROfE0A@public.gmane.org>
2008-07-03 17:43   ` Dmitry Torokhov
2008-07-03 22:08     ` Oliver Neukum
     [not found]       ` <200807040008.50174.oliver-GvhC2dPhHPQdnm+yROfE0A@public.gmane.org>
2008-07-03 22:13         ` Oliver Neukum [this message]

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=200807040013.54237.oliver@neukum.org \
    --to=oliver-gvhc2dphhpqdnm+yrofe0a@public.gmane.org \
    --cc=dmitry.torokhov-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org \
    --cc=linux-input-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
    --cc=linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
    --cc=will-ffEBwZeNOFERmelmmXo44Q@public.gmane.org \
    /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