[lkml]   [2009]   [Jul]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
SubjectRe: [PATCH] kdesu broken
I'd favour we go with this which passes t1, expect, emacs and a corrected

(test t3 is buggy as it has no \n and leaves the tty in line by line mode
so its typing a long line at the pty but never hits return to finish the

It's theoretically imperfect in the case where you write a vast amount of
output in one go, the tty is blocked the other end and then you close.
However in practice that doesn't happen because with tty->low_latency = 1
we run the pty received n_tty ldisc code in our context so each write
fires through the entire n_tty ldisc and does flow control synchronously.

It needs re-addressing but its simple which at this point wins over
everything else and its one people tested before we tried to fix the hard
corner cases

commit aaf9da79c95a32fc5286fb851632baf09dc6134b
Author: Alan Cox <>
Date: Mon Jul 27 22:17:51 2009 +0100

pty: quickfix for the pty ENXIO timing problems

This also makes close stall in the normal case which is apparently needed
to fix emacs

Signed-off-by: Alan Cox <>

diff --git a/drivers/char/pty.c b/drivers/char/pty.c
index 6e6942c..3850a68 100644
--- a/drivers/char/pty.c
+++ b/drivers/char/pty.c
@@ -52,6 +52,7 @@ static void pty_close(struct tty_struct *tty, struct file *filp)
tty->link->packet = 0;
set_bit(TTY_OTHER_CLOSED, &tty->link->flags);
+ tty_flip_buffer_push(tty->link);
if (tty->driver->subtype == PTY_TYPE_MASTER) {
@@ -207,6 +208,7 @@ static int pty_open(struct tty_struct *tty, struct file *filp)
clear_bit(TTY_OTHER_CLOSED, &tty->link->flags);
set_bit(TTY_THROTTLED, &tty->flags);
retval = 0;
+ tty->low_latency = 1;
return retval;

 \ /
  Last update: 2009-07-27 23:43    [W:0.234 / U:0.760 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site