Re: PATCH: tty locking for 2.6.9rc2

Alan Cox
2004-09-15T16:33:17Z

On Wed, Sep 15, 2004 at 11:26:35AM -0500, Paul Fulghum wrote:
> I tried this patch and can't change line disciplines.
> The user program waits forever on ioctl(TIOCSETD).
> I am going to add printk statements to

Is the tty currently in use - that implies maybe an ldisc leak

> Each line discipline has a refcount.
> This single refcount is modified by all
> entities using that line discipline.

Nope. tty->ldisc is a -copy- of the ldisc structure rather than a
pointer. It has always been that way

struct tty_struct {
int magic;
struct tty_driver *driver;
int index;
struct tty_ldisc ldisc;

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