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Subject: Re: BUG: scheduling while atomic: ifconfig/0x00000002/4170
From: Johannes Berg <johannes@sipsolutions.net>
To: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Satyam Sharma <satyam@infradead.org>,
	Florian Lohoff <flo@rfc822.org>,
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Date: Thu, 06 Sep 2007 17:19:55 +0200
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On Thu, 2007-09-06 at 16:23 +0800, Herbert Xu wrote:
> On Thu, Sep 06, 2007 at 10:32:33AM +0530, Satyam Sharma wrote:
> >=20
> > > > [  382.529041]  [<c02c8abc>] dev_close+0x24/0x67
> > > > [  382.529052]  [<e01f402b>] ieee80211_master_stop+0x4a/0x6d [mac80=
211]
>=20
> This is where the bug is.  You cannot call dev_close from an
> atomic context as i33380211_master_stop does it within spin
> locks.

Oh btw. Can we stick a might_sleep() into dev_close() *before* the test
whether the device is up? That way, we'd have seen the bug, but
apparently nobody before Florian ever did a 'ip link set wmaster0 down'
while the other interfaces were still open.

johannes

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