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Message-ID: <5bbc9f7d3a01cd578cbf894469734d88c8f59279.camel@sipsolutions.net>
Subject: Re: [PATCH] mac80211: keep BHs disabled while calling
 drv_tx_wake_queue()
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Jiri Kosina <jikos@kernel.org>,
        Toke =?ISO-8859-1?Q?H=F8iland-J=F8rgensen?= <toke@redhat.com>
Cc:     linux-wireless@vger.kernel.org, Aaron Hill <aa1ronham@gmail.com>,
        Lukas Redlinger <rel+kernel@agilox.net>,
        Oleksii Shevchuk <alxchk@gmail.com>
Date:   Tue, 01 Oct 2019 13:01:12 +0200
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References: <1569924485-I3e8838c5ecad878e59d4a94eb069a90f6641461a@changeid>
         <87blv0visz.fsf@toke.dk>
         <nycvar.YFH.7.76.1910011256001.13160@cbobk.fhfr.pm>
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On Tue, 2019-10-01 at 12:56 +0200, Jiri Kosina wrote:
> On Tue, 1 Oct 2019, Toke Høiland-Jørgensen wrote:
> 
> > > -			spin_unlock_bh(&fq->lock);
> > > +			spin_unlock(&fq->lock);
> > >  			drv_wake_tx_queue(local, txqi);
> > > -			spin_lock_bh(&fq->lock);
> > > +			spin_lock(&fq->lock);
> > 
> > Okay, so this will mean that the drv_wake_tx_queue() entry point will be
> > called with bhs disabled. But there are lots of uses of
> > spin_{,un}lock_bh() in tx.c:
> 
> I am fine with whatever fix for this you guys settle on :) Just for the 
> record, I proposed this back then:
> 
> 	http://lore.kernel.org/r/nycvar.YFH.7.76.1904151300160.9803@cbobk.fhfr.pm
> 
> maybe it could be resurected, as I believe it'd fix this one as well?

Yes, it would, but it wouldn't address any other driver that likely has
the same issue :)

johannes