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Message-ID: <55c963dce43d8cf614a5401a23750d3b30399e45.camel@decadent.org.uk>
Subject: Re: [PATCH 3.16 23/99] tty/ldsem: Wake up readers after timed out
 down_write()
From:   Ben Hutchings <ben@decadent.org.uk>
To:     Dmitry Safonov <0x7f454c46@gmail.com>
Cc:     open list <linux-kernel@vger.kernel.org>,
        stable <stable@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Denis Kirjanov <kda@linux-powerpc.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jiri Slaby <jslaby@suse.com>,
        kernel test robot <rong.a.chen@intel.com>,
        Dmitry Safonov <dima@arista.com>,
        Peter Zijlstra <peterz@infradead.org>
Date:   Tue, 07 May 2019 19:38:03 +0100
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On Tue, 2019-04-02 at 15:39 +0100, Dmitry Safonov wrote:
> On 4/2/19 3:32 PM, Ben Hutchings wrote:
> > On Tue, 2019-04-02 at 15:22 +0100, Dmitry Safonov wrote:
[...]
> > > - "tty: Hold tty_ldisc_lock() during tty_reopen()" commit 83d817f4107=
0
> > >   with follow-up fixup "tty: Don't hold ldisc lock in tty_reopen() if
> > > ldisc present"
> > >   commit d3736d82e816
> > [...]
> >=20
> > I will include these in a later update, unless you think they are
> > really urgent and should be added to this one.
>=20
> Well, I thought worth to mention those patches, but in reality haven't
> checked if they are applicable to v3.16.
> It's just I remember "tty: Hold tty_ldisc_lock() during tty_reopen()"
> was the main fix in the set, as many people suffered from issue under
> it, so I thought strange that only a side-patch (which can lead to soft
> lockup, so probably also important) is ported. But I managed to forget
> that the code has changes since v3.16.

I couldn't see how to apply these to 3.16, so you will need to send me
backports if they are needed.  They are also missing from 3.18 and 4.4.

Ben.

--=20
Ben Hutchings
Teamwork is essential - it allows you to blame someone else.


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