Re: Race in n_tty.c write_chan()

[Al Borchers]

Andrea Arcangeli wrote: 
> Good spotting. This below is the right fix for 2.2.16pre6. Taking page
> faults with the task in interruptible state is safe.

Great!  When do you think this patch will appear in the 2.2 and 2.4 kernels?
It will help us out.

-- Al
 
> --- 2.2.17pre6aa2/drivers/char/n_tty.c  Tue Jun 13 03:48:13 2000
> +++ 2.2.14/drivers/char/n_tty.c Mon Jan 17 16:44:37 2000
> @@ -1142,9 +1094,7 @@
>                                 nr -= num;
>                                 if (nr == 0)
>                                         break;
> -                               current->state = TASK_RUNNING;
>                                 get_user(c, b);
> -                               current->state = TASK_INTERRUPTIBLE;
>                                 if (opost(c, tty) < 0)
>                                         break;
>                                 b++; nr--;
> @@ -1152,9 +1102,7 @@
>                         if (tty->driver.flush_chars)
>                                 tty->driver.flush_chars(tty);
>                 } else {
> -                       current->state = TASK_RUNNING;
>                         c = tty->driver.write(tty, 1, b, nr);
> -                       current->state = TASK_INTERRUPTIBLE;
>                         if (c < 0) {
>                                 retval = c;
>                                 goto break_out;