From: Andrew Morton <akpm@linux-foundation.org>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Joe Peterson <joe@skyrush.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] TTY: Fix loss of echoed characters (2nd follow-on PATCH attached)
Date: Tue, 9 Sep 2008 10:43:25 -0700 [thread overview]
Message-ID: <20080909104325.4653190b.akpm@linux-foundation.org> (raw)
In-Reply-To: <20080909115536.1664d57a@lxorguk.ukuu.org.uk>
On Tue, 9 Sep 2008 11:55:36 +0100 Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
> On Mon, 8 Sep 2008 17:32:50 -0700
> Andrew Morton <akpm@linux-foundation.org> wrote:
>
> > On Mon, 08 Sep 2008 10:11:46 -0600
> > Joe Peterson <joe@skyrush.com> wrote:
> >
> > > + spin_lock_irqsave(&tty->echo_lock, flags);
> > > lock_kernel();
> >
> > Taking a spinlock outside lock_kernel() isn't good, and is quite unusual.
> >
> > - It might be ab/ba deadlockable (I didn't check) (I trust you always
> > test with lockdep enabled?)
>
> lock_kernel can sleep.
That used to be the case, but the mutex_lock() version of the bkl got
removed. It may of course come back.
> Its not allowed...
>
yup.
next prev parent reply other threads:[~2008-09-09 17:44 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <200807252257.m6PMvieO003213@imap1.linux-foundation.org>
2008-08-20 15:36 ` [PATCH] TTY: Fix loss of echoed characters Joe Peterson
2008-08-26 12:41 ` Joe Peterson
2008-09-08 16:11 ` [PATCH] TTY: Fix loss of echoed characters (2nd follow-on PATCH attached) Joe Peterson
2008-09-09 0:32 ` Andrew Morton
2008-09-09 10:55 ` Alan Cox
2008-09-09 17:43 ` Andrew Morton [this message]
2008-09-09 20:42 ` Joe Peterson
2008-09-10 23:39 ` Andrew Morton
2008-09-11 12:53 ` Joe Peterson
2008-09-09 13:00 ` Joe Peterson
2008-09-09 13:12 ` Alan Cox
2008-09-09 13:15 ` Joe Peterson
2008-09-09 13:19 ` Alan Cox
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