[lkml]   [2003]   [Jan]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: Fixing the tty layer was Re: any chance of 2.6.0-test*?
On Mon, Jan 13, 2003 at 08:25:39AM +0100, Andi Kleen wrote:
> > Oh, yes, I have spent hours and hours trying to untangle tty locking
> > and it isn't simple.
> Oops. Could you quickly summarize your findings so far ?

I only found more confusions - I can't figure how tty_files list
is locked - sure files_lock is supposed to protect it but there
are deletions done without any lock. Another thing that needs
looking into is to avoid or reduce use of the tasklist_lock there.

> > What does that BKL protect ? I can't seem to ever figure our if
> > all the races are plugged or not.
> Well, one has to start somewhere. Just starting by plugging most of the
> obvious races, then the more subtle ones can be attacked later.
> The idea of the BKL was to protect the protect context code against
> itself (code lock) and also the few global data structures that
> are only accessed from process context (like the tty drivers list)

In that case would it not be better to replace all BKLs by a single tty
lock ?

> I attached my current patch, it isn't too well tested however and needs
> more work.
> Mostly just adds lock_kernel()s to the high level code so far and a few comments.

Cool, I will start off by testing this stuff.

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2005-03-22 13:32    [W:0.062 / U:2.800 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site