On Tue, 2013-04-02 at 18:56 +0530, Vineet Gupta wrote: > On 04/01/2013 08:40 PM, Peter Hurley wrote: > > On Mon, 2013-04-01 at 19:27 +0530, Vineet Gupta wrote: > >> On 03/30/2013 06:05 PM, Vineet Gupta wrote: > >>> Hung find task is sitting in the schedule() call in n_tty_write() > >>> > >>> [ARCLinux]$ cat /proc/281/stack > >>> [<8065945e>] n_tty_write+0x23a/0x424 > >>> [<80655cd4>] tty_write+0x1ac/0x2d4 > >>> [<805976ba>] vfs_write+0x92/0x110 > >>> [<80597816>] sys_write+0x4e/0x88 > >>> [<8050e780>] ret_from_system_call+0x0/0x4 > > Likely the writer is stuck because the receive buffer is full and the > > reader is hung. What are the respective shells and telnetd doing? > > I don't undersand how the receive buffer full/empty is coming into play - that > schedule() call is not a wait queue or something If n_tty_write() blocks [the schedule() call], then it is on a wait queue (tty->write_wait) which is woken by pty's unthrottle() called from n_tty_read from the linked pty when space becomes available in the receive buffer. -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
