Uwe Kleine-König df2dc4cf71 serial: 8250: Fix race condition in RTS-after-send handling ... [ Upstream commit dedab69fd6 ] Set em485->active_timer = NULL isn't always enough to take out the stop timer. While there is a check that it acts in the right state (i.e. waiting for RTS-after-send to pass after sending some chars) but the following might happen: - CPU1: some chars send, shifter becomes empty, stop tx timer armed - CPU0: more chars send before RTS-after-send expired - CPU0: shifter empty irq, port lock taken - CPU1: tx timer triggers, waits for port lock - CPU0: em485->active_timer = &em485->stop_tx_timer, hrtimer_start(), releases lock() - CPU1: get lock, see em485->active_timer == &em485->stop_tx_timer, tear down RTS too early This fix bases on research done by Steffen Trumtrar. Fixes: b86f86e8e7 ("serial: 8250: fix potential deadlock in rs485-mode") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20220215160236.344236-1-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2022-04-08 14:40:25 +02:00
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hvc	xen/console: harden hvc_xen against event channel storms	2021-12-22 09:30:59 +01:00
ipwireless
serdev
serial	serial: 8250: Fix race condition in RTS-after-send handling	2022-04-08 14:40:25 +02:00
vt	vt_ioctl: add array_index_nospec to VT_ACTIVATE	2022-02-16 12:54:27 +01:00
amiserial.c	tty: amiserial: fix TIOCSSERIAL permission check	2021-05-14 09:49:55 +02:00
cyclades.c
ehv_bytechan.c
goldfish.c
isicom.c
Kconfig
Makefile
mips_ejtag_fdc.c
moxa.c	tty: moxa: fix TIOCSSERIAL permission check	2021-05-14 09:49:56 +02:00
moxa.h
mxser.c	mxser: fix xmit_buf leak in activate when LSR == 0xff	2022-04-08 14:40:23 +02:00
mxser.h
n_gsm.c	tty: n_gsm: fix deadlock in gsmtty_open()	2022-03-02 11:42:57 +01:00
n_hdlc.c	tty: n_hdlc: make n_hdlc_tty_wakeup() asynchronous	2021-12-22 09:30:56 +01:00
n_null.c
n_r3964.c
n_tracerouter.c
n_tracesink.c
n_tracesink.h
n_tty.c	tty: n_tty: do not look ahead for EOL character past the end of the buffer	2022-02-23 12:01:04 +01:00
nozomi.c	tty: nozomi: Fix the error handling path of 'nozomi_card_init()'	2021-07-14 16:56:39 +02:00
pty.c
rocket_int.h
rocket.c
rocket.h
synclink_gt.c	tty: synclink_gt: rename a conflicting function name	2021-09-30 10:11:03 +02:00
synclink.c
synclinkmp.c
sysrq.c
tty_audit.c
tty_baudrate.c
tty_buffer.c	tty: tty_buffer: Fix the softlockup issue in flush_to_ldisc	2021-11-26 10:39:10 +01:00
tty_io.c	tty: Fix data race between tiocsti() and flush_to_ldisc()	2021-09-15 09:50:47 +02:00
tty_ioctl.c	tty: fix return value for unsupported termiox ioctls	2021-05-14 09:50:19 +02:00
tty_jobctrl.c
tty_ldisc.c
tty_ldsem.c
tty_mutex.c
tty_port.c
ttynull.c
vcc.c