On Fri, Mar 12, 2010 at 11:53:15AM +0530, Amit Shah wrote: > Alan pointed out a race in the code where hvc_remove is invoked. The > recent virtio_console work is the first user of hvc_remove(). > > Alan describes it thus: > > The hvc_console assumes that a close and remove call can't occur at the > same time. > > In addition tty_hangup(tty) is problematic as tty_hangup is asynchronous > itself.... > > So this can happen > > hvc_close hvc_remove > hung up ? - no > lock > tty = hp->tty > unlock > lock > hp->tty = NULL > unlock > notify del > kref_put the hvc struct > close completes > tty is destroyed > tty_hangup dead tty > tty->ops will be NULL > NULL->... > > This patch adds some tty krefs and also converts to using tty_vhangup(). > > Reported-by: Alan Cox <a...@lxorguk.ukuu.org.uk> > Signed-off-by: Amit Shah <amit.s...@redhat.com> > CC: Alan Cox <a...@lxorguk.ukuu.org.uk> > CC: linuxppc-...@ozlabs.org > CC: Rusty Russell <ru...@rustcorp.com.au> > --- > > Linus, sending to you this time as I didn't receive any response from > Ben or Greg for the previous submissions.
It's in my "to-apply" queue. Which I was ignoring due to the -rc1 merge, and then I've been busy with -stable stuff and a conference this week. I'll get to it soon. thanks for your patience, greg k-h _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
