From: Aristeu Rozanski <aris@redhat.com>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: linux-kernel@vger.kernel.org, akpm@linux-foundation.org,
jirislaby@gmail.com
Subject: Re: [PATCH] vt: kill tty->count usage (v2)
Date: Tue, 19 Aug 2008 13:03:17 -0400 [thread overview]
Message-ID: <20080819170317.GC7154@redhat.com> (raw)
In-Reply-To: <20080819160318.26f70590@lxorguk.ukuu.org.uk>
Hi Alan,
> > > > The commit e0426e6a09954d205da2d674a3d368d2715e3afd fixes a real race but
> > > > still isn't enough to prevent these:
> > > >
> > > > kobject_add_internal failed for vcs7 with -EEXIST, don't try to register
> > > > things with the same name in the same direc.
> > >
> > > Patch dropped due to testing failures.
> > >
> > > Boot to run level 3, log in and type "reboot\n". Wait
> > >
> > > Spews vt->driver_data == NULL warnings and oopses
> > do you mind posting the logs somewhere? I wasn't able to reproduce it here so
>
> I decided it might be better to tackle this one 'head on' and go to the
> root of the problem. I've pushed the following into the stack of patches
> for -next
>
> tty: shutdown method
I agree with the idea, but:
> /**
> * release_one_tty - release tty structure memory
> * @kref: kref of tty we are obliterating
> @@ -1489,27 +1514,11 @@ static void release_one_tty(struct kref *kref)
> {
> struct tty_struct *tty = container_of(kref, struct tty_struct, kref);
> struct tty_driver *driver = tty->driver;
> - int devpts = tty->driver->flags & TTY_DRIVER_DEVPTS_MEM;
> - struct ktermios *tp;
> - int idx = tty->index;
> -
> - if (!devpts)
> - tty->driver->ttys[idx] = NULL;
> -
> - if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) {
> - /* FIXME: Locking on ->termios array */
> - tp = tty->termios;
> - if (!devpts)
> - tty->driver->termios[idx] = NULL;
> - kfree(tp);
> -
> - tp = tty->termios_locked;
> - if (!devpts)
> - tty->driver->termios_locked[idx] = NULL;
> - kfree(tp);
> - }
> -
>
> + if (tty->ops->shutdown)
> + tty->ops->shutdown(tty);
> + else
> + tty_shutdown(tty);
> tty->magic = 0;
> /* FIXME: locking on tty->driver->refcount */
> tty->driver->refcount--;
isn't too late for drivers that wait for the remaining data to be transmitted
such as amiserial and cyclades? Unless there's a plan to do it at
release_dev()?
--
Aristeu
next prev parent reply other threads:[~2008-08-19 17:04 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-08-08 21:36 [PATCH] vt: kill tty->count usage Aristeu Rozanski
2008-08-08 21:26 ` Alan Cox
2008-08-12 14:58 ` [PATCH] vt: kill tty->count usage (v2) Aristeu Rozanski
2008-08-15 9:58 ` Alan Cox
2008-08-18 17:19 ` Alan Cox
2008-08-18 21:04 ` Aristeu Rozanski
2008-08-18 21:01 ` Alan Cox
2008-08-19 12:37 ` Alan Cox
2008-08-19 15:03 ` Alan Cox
2008-08-19 17:03 ` Aristeu Rozanski [this message]
2008-08-19 17:14 ` Alan Cox
2008-08-20 0:03 ` Aristeu Rozanski
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