linux/drivers/tty
Marek Roszko 8bc661bfc0 tty/serial: at91: disable uart timer at start of shutdown
The uart timer will schedule a tasklet when it fires. It is possible that it
can fire inside _shutdown before it is killed in the dma and pdc cleanup
routines. This causes a tasklet that exists after the port is shutdown, so when
the kernel finally executes it, it panics as the tty port is NULL.

This is a somewhat rare condition but its possible if a program keeps on
opening/closing the port. It has been observed in particular with systemd
boot messages that were causing a kernel panic because of this behavior.

Moving the timer deletion to the beginning of the function stops a tasklet from
being scheduled unexpectedly.

Signed-off-by: Marek Roszko <mark.roszko@gmail.com>
Cc: stable <stable@vger.kernel.org> # v3.12
[nicolas.ferre@atmel.com: modify commit message, call setup_timer() in any case]
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-01-13 15:55:59 -08:00
..
hvc
ipwireless
serial
vt
amiserial.c
bfin_jtag_comm.c
cyclades.c
ehv_bytechan.c
goldfish.c
isicom.c
Kconfig
Makefile
metag_da.c
moxa.c
moxa.h
mxser.c
mxser.h
n_gsm.c
n_hdlc.c
n_r3964.c
n_tracerouter.c
n_tracesink.c
n_tracesink.h
n_tty.c
nozomi.c
pty.c
rocket.c
rocket.h
rocket_int.h
synclink.c
synclink_gt.c
synclinkmp.c
sysrq.c
tty_audit.c
tty_buffer.c
tty_io.c
tty_ioctl.c
tty_ldisc.c
tty_ldsem.c
tty_mutex.c
tty_port.c