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Message-ID: <1566308421.11678.18.camel@suse.com>
Subject: Re: WARNING in wdm_write/usb_submit_urb
From:   Oliver Neukum <oneukum@suse.com>
To:     =?ISO-8859-1?Q?Bj=F8rn?= Mork <bjorn@mork.no>
Cc:     gustavo@embeddedor.com, andreyknvl@google.com,
        syzkaller-bugs@googlegroups.com, gregkh@linuxfoundation.org,
        syzbot <syzbot+d232cca6ec42c2edb3fc@syzkaller.appspotmail.com>,
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Date:   Tue, 20 Aug 2019 15:40:21 +0200
In-Reply-To: <87imqs56ae.fsf@miraculix.mork.no>
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         <1566304128.11678.14.camel@suse.com><1566304128.11678.14.camel@suse.com>
         (Oliver Neukum's message of "Tue, 20 Aug 2019 14:28:48 +0200") <87imqs56ae.fsf@miraculix.mork.no>
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Am Dienstag, den 20.08.2019, 15:13 +0200 schrieb Bjørn Mork :
> Oliver Neukum <oneukum@suse.com> writes:
> 
> > +	wait_event(desc->wait,
> > +			/*
> > +			 * needs both flags. We cannot do with one
> > +			 * because resetting it would cause a race
> > +			 * with write() yet we need to signal
> > +			 * a disconnect
> > +			 */
> > +			!test_bit(WDM_IN_USE, &desc->flags) &&
> > +			test_bit(WDM_DISCONNECTING, &desc->flags));
> 
> I'm confused now...  Won't this condition always be false?
> Should be
> 
>   wait_event(desc->wait,
>              !test_bit(WDM_IN_USE, &desc->flags) ||
>              test_bit(WDM_DISCONNECTING, &desc->flags));
> 
> 
> instead, or?


<censored> <censored> ...

You are right.

	Regards
		Oliver