Linux wireless drivers development
 help / color / mirror / Atom feed
From: Dan Williams <dcbw@redhat.com>
To: linux-wireless@vger.kernel.org
Subject: mac80211 ad-hoc mode problems
Date: Tue, 03 Jun 2008 21:41:04 -0400	[thread overview]
Message-ID: <1212543664.4237.14.camel@localhost.localdomain> (raw)

Hi,

While adding adhoc shared network support to NM, I ran into a few
mac80211 problems.

1) doesn't send SIOCGIWAP event on successful adhoc activation (patch
forthcoming)

2) takes a _really_ long time to create an adhoc network.  This is
controlled by IEEE80211_IBSS_JOIN_TIMEOUT.  Why is that 20 seconds?  Th=
e
problem here is that wpa_supplicant has an association timer shorter
than =EF=BB=BFIEEE80211_IBSS_JOIN_TIMEOUT and will re-try the connectio=
n,
causing mac80211 to reset ifsta->ibss_join_req.  FullMAC drivers will
simply look in their scan list (and optionally perform one scan) and if
the IBSS isn't found, create it.  I'd really like to
take =EF=BB=BFIEEE80211_IBSS_JOIN_TIMEOUT down to 5 or 7 seconds.  This=
 is only
the initial IBSS creation, IBSS merging will still be in effect.  I
simply thing 20 seconds is really too long here.

3) doesn't send NULL SIOCGIWAP disassoc events when the device goes dow=
n
or the module is removed.  Where's the best place to put the event on
module remove?

4) Is the association expected to survive a up->down->up sequence?  If
not, then we should be sending NULL SIOCGIWAP event whenever dev_close(=
)
gets called.

5) mac80211 requires the device to be down when changing modes.  That's
fine; but requires a patch to wpa_supplicant to handle this.  This woul=
d
cause failures when switching AP that were different modes from NM.
See:

http://lists.shmoo.com/pipermail/hostap/2008-June/017894.html

Dan

--
To unsubscribe from this list: send the line "unsubscribe linux-wireles=
s" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

             reply	other threads:[~2008-06-04  1:41 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-06-04  1:41 Dan Williams [this message]
2008-06-04  9:00 ` mac80211 ad-hoc mode problems Johannes Berg
2008-06-04  9:16   ` Jouni Malinen
2008-06-04 14:18     ` Dan Williams
2008-06-04 15:41       ` Johannes Berg
2008-06-04 15:55       ` Jouni Malinen
2008-06-04 17:30         ` Dan Williams
2008-06-04 14:13   ` Dan Williams
2008-06-04 15:44     ` Johannes Berg

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=1212543664.4237.14.camel@localhost.localdomain \
    --to=dcbw@redhat.com \
    --cc=linux-wireless@vger.kernel.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