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From:   caelli <juanfengpy@gmail.com>
Date:   Tue, 4 Apr 2023 15:02:27 +0800
Message-ID: <CAPmgiUJhocwGweOYmJcYY47CONwJAqgLA7AdDzD=Quepd6u5cw@mail.gmail.com>
Subject: Re: [PATCH v7] tty: fix hang on tty device with no_room set
To:     Bagas Sanjaya <bagasdotme@gmail.com>
Cc:     Hui Li <caelli@tencent.com>, stable@vger.kernel.org,
        =?UTF-8?Q?Ilpo_J=C3=A4rvinen?= <ilpo.jarvinen@linux.intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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> Where do you find this hanging pty? Seems like the wording makes me
> confused. Maybe you mean "It is possible to hang pty device. In that
> case, ..."

Thanks for your reply, I will correct messages like this:

"It is possible to hang pty devices in this case, the reader
was blocking at epoll on master side, the writer was ..."

Bagas Sanjaya <bagasdotme@gmail.com> =E4=BA=8E2023=E5=B9=B44=E6=9C=884=E6=
=97=A5=E5=91=A8=E4=BA=8C 10:55=E5=86=99=E9=81=93=EF=BC=9A
>
> On 4/4/23 09:49, Bagas Sanjaya wrote:
> > On Fri, Mar 17, 2023 at 10:24:07AM +0800, juanfengpy@gmail.com wrote:
> >> We have met a hang on pty device, the reader was blocking
> >> at epoll on master side, the writer was sleeping at wait_woken
> >> inside n_tty_write on slave side, and the write buffer on
> >> tty_port was full, we found that the reader and writer would
> >> never be woken again and blocked forever.
> >
> > Where do you find this hanging pty? Seems like the wording makes me
> > confused. Maybe you mean "It is possible to hang pty device. In that
> > case, ..."
> >
>
> Oops, I forgot to Cc: LKML.
>
> --
> An old man doll... just what I always wanted! - Clara
>