re /drivers/char/n_tty.c drops characters

re /drivers/char/n_tty.c drops characters

[Denis Joseph Barrow]

Hi,
There are functions tty_throttle & tty_unthrottle
called from the n_tty line discipline, it might do everything
I want it to do.

I might be plain wrong & casting asparagus about my understanding of
the n_tty & it might not drop packets
in the latest kernel.

If I'm wrong about n_tty.c & being stupid thinking the n_tty layer 
drops packets please inform me & tell me why it doesn't.

Is whats in n_tty bulletproof if used properly.
-- 
best regards,
D.J. Barrow

re /drivers/char/n_tty.c drops characters

[Denis Joseph Barrow]

Hi all,
It looks like the it was the intention that n_tty.c
would not drop characters in older kernels around 2.6.15 in the
n_tty layer if N_TTY_BUF_SIZE was 4096 bytes
as TTY_FLIPBUF_SIZE was only 512 bytes.

Now since 2.6.15 or so tty_buffer_alloc in tty_io.c is capible
of allocating a tty buffer of over 64k I believe this
means that the n_tty_receive_buf will overflow if tty_buffer_alloc 
throws a buffer of over 4k to n_tty_receive_buf.

Any comments?

-- 
best regards,
D.J. Barrow