linux-stable.git/drivers/tty, branch v4.18.19 Linux kernel stable tree kgdboc: Passing ekgdboc to command line causes panic 2018-11-13T19:12:49+00:00 He Zhe zhe.he@windriver.com 2018-08-17T14:42:28+00:00 239efda32abd24c270a0348f678cb3a99223189b commit 1bd54d851f50dea6af30c3e6ff4f3e9aab5558f9 upstream. kgdboc_option_setup does not check input argument before passing it to strlen. The argument would be a NULL pointer if "ekgdboc", without its value, is set in command line and thus cause the following panic. PANIC: early exception 0xe3 IP 10:ffffffff8fbbb620 error 0 cr2 0x0 [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.18-rc8+ #1 [ 0.000000] RIP: 0010:strlen+0x0/0x20 ... [ 0.000000] Call Trace [ 0.000000] ? kgdboc_option_setup+0x9/0xa0 [ 0.000000] ? kgdboc_early_init+0x6/0x1b [ 0.000000] ? do_early_param+0x4d/0x82 [ 0.000000] ? parse_args+0x212/0x330 [ 0.000000] ? rdinit_setup+0x26/0x26 [ 0.000000] ? parse_early_options+0x20/0x23 [ 0.000000] ? rdinit_setup+0x26/0x26 [ 0.000000] ? parse_early_param+0x2d/0x39 [ 0.000000] ? setup_arch+0x2f7/0xbf4 [ 0.000000] ? start_kernel+0x5e/0x4c2 [ 0.000000] ? load_ucode_bsp+0x113/0x12f [ 0.000000] ? secondary_startup_64+0xa5/0xb0 This patch adds a check to prevent the panic. Cc: stable@vger.kernel.org Cc: jason.wessel@windriver.com Cc: gregkh@linuxfoundation.org Cc: jslaby@suse.com Signed-off-by: He Zhe <zhe.he@windriver.com> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 1bd54d851f50dea6af30c3e6ff4f3e9aab5558f9 upstream.

kgdboc_option_setup does not check input argument before passing it
to strlen. The argument would be a NULL pointer if "ekgdboc", without
its value, is set in command line and thus cause the following panic.

PANIC: early exception 0xe3 IP 10:ffffffff8fbbb620 error 0 cr2 0x0
[    0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.18-rc8+ #1
[    0.000000] RIP: 0010:strlen+0x0/0x20
...
[    0.000000] Call Trace
[    0.000000]  ? kgdboc_option_setup+0x9/0xa0
[    0.000000]  ? kgdboc_early_init+0x6/0x1b
[    0.000000]  ? do_early_param+0x4d/0x82
[    0.000000]  ? parse_args+0x212/0x330
[    0.000000]  ? rdinit_setup+0x26/0x26
[    0.000000]  ? parse_early_options+0x20/0x23
[    0.000000]  ? rdinit_setup+0x26/0x26
[    0.000000]  ? parse_early_param+0x2d/0x39
[    0.000000]  ? setup_arch+0x2f7/0xbf4
[    0.000000]  ? start_kernel+0x5e/0x4c2
[    0.000000]  ? load_ucode_bsp+0x113/0x12f
[    0.000000]  ? secondary_startup_64+0xa5/0xb0

This patch adds a check to prevent the panic.

Cc: stable@vger.kernel.org
Cc: jason.wessel@windriver.com
Cc: gregkh@linuxfoundation.org
Cc: jslaby@suse.com
Signed-off-by: He Zhe <zhe.he@windriver.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Revert "serial: 8250_dw: Fix runtime PM handling" 2018-11-04T13:51:47+00:00 Guenter Roeck linux@roeck-us.net 2018-10-02T04:42:37+00:00 1ac18a1dbc3f2f1fa67d57db57d85308cbd8680c [ Upstream commit beeeac43b6fae5f5eaf707b6fcc2bf1e09deb785 ] This reverts commit d76c74387e1c978b6c5524a146ab0f3f72206f98. While commit d76c74387e1c ("serial: 8250_dw: Fix runtime PM handling") fixes runtime PM handling when using kgdb, it introduces a traceback for everyone else. BUG: sleeping function called from invalid context at /mnt/host/source/src/third_party/kernel/next/drivers/base/power/runtime.c:1034 in_atomic(): 1, irqs_disabled(): 1, pid: 1, name: swapper/0 7 locks held by swapper/0/1: #0: 000000005ec5bc72 (&dev->mutex){....}, at: __driver_attach+0xb5/0x12b #1: 000000005d5fa9e5 (&dev->mutex){....}, at: __device_attach+0x3e/0x15b #2: 0000000047e93286 (serial_mutex){+.+.}, at: serial8250_register_8250_port+0x51/0x8bb #3: 000000003b328f07 (port_mutex){+.+.}, at: uart_add_one_port+0xab/0x8b0 #4: 00000000fa313d4d (&port->mutex){+.+.}, at: uart_add_one_port+0xcc/0x8b0 #5: 00000000090983ca (console_lock){+.+.}, at: vprintk_emit+0xdb/0x217 #6: 00000000c743e583 (console_owner){-...}, at: console_unlock+0x211/0x60f irq event stamp: 735222 __down_trylock_console_sem+0x4a/0x84 console_unlock+0x338/0x60f __do_softirq+0x4a4/0x50d irq_exit+0x64/0xe2 CPU: 2 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc5 #6 Hardware name: Google Caroline/Caroline, BIOS Google_Caroline.7820.286.0 03/15/2017 Call Trace: dump_stack+0x7d/0xbd ___might_sleep+0x238/0x259 __pm_runtime_resume+0x4e/0xa4 ? serial8250_rpm_get+0x2e/0x44 serial8250_console_write+0x44/0x301 ? lock_acquire+0x1b8/0x1fa console_unlock+0x577/0x60f vprintk_emit+0x1f0/0x217 printk+0x52/0x6e register_console+0x43b/0x524 uart_add_one_port+0x672/0x8b0 ? set_io_from_upio+0x150/0x162 serial8250_register_8250_port+0x825/0x8bb dw8250_probe+0x80c/0x8b0 ? dw8250_serial_inq+0x8e/0x8e ? dw8250_check_lcr+0x108/0x108 ? dw8250_runtime_resume+0x5b/0x5b ? dw8250_serial_outq+0xa1/0xa1 ? dw8250_remove+0x115/0x115 platform_drv_probe+0x76/0xc5 really_probe+0x1f1/0x3ee ? driver_allows_async_probing+0x5d/0x5d driver_probe_device+0xd6/0x112 ? driver_allows_async_probing+0x5d/0x5d bus_for_each_drv+0xbe/0xe5 __device_attach+0xdd/0x15b bus_probe_device+0x5a/0x10b device_add+0x501/0x894 ? _raw_write_unlock+0x27/0x3a platform_device_add+0x224/0x2b7 mfd_add_device+0x718/0x75b ? __kmalloc+0x144/0x16a ? mfd_add_devices+0x38/0xdb mfd_add_devices+0x9b/0xdb intel_lpss_probe+0x7d4/0x8ee intel_lpss_pci_probe+0xac/0xd4 pci_device_probe+0x101/0x18e ... Revert the offending patch until a more comprehensive solution is available. Cc: Tony Lindgren <tony@atomide.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Phil Edworthy <phil.edworthy@renesas.com> Fixes: d76c74387e1c ("serial: 8250_dw: Fix runtime PM handling") Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit beeeac43b6fae5f5eaf707b6fcc2bf1e09deb785 ]

This reverts commit d76c74387e1c978b6c5524a146ab0f3f72206f98.

While commit d76c74387e1c ("serial: 8250_dw: Fix runtime PM handling")
fixes runtime PM handling when using kgdb, it introduces a traceback for
everyone else.

BUG: sleeping function called from invalid context at
	/mnt/host/source/src/third_party/kernel/next/drivers/base/power/runtime.c:1034
in_atomic(): 1, irqs_disabled(): 1, pid: 1, name: swapper/0
7 locks held by swapper/0/1:
 #0: 000000005ec5bc72 (&dev->mutex){....}, at: __driver_attach+0xb5/0x12b
 #1: 000000005d5fa9e5 (&dev->mutex){....}, at: __device_attach+0x3e/0x15b
 #2: 0000000047e93286 (serial_mutex){+.+.}, at: serial8250_register_8250_port+0x51/0x8bb
 #3: 000000003b328f07 (port_mutex){+.+.}, at: uart_add_one_port+0xab/0x8b0
 #4: 00000000fa313d4d (&port->mutex){+.+.}, at: uart_add_one_port+0xcc/0x8b0
 #5: 00000000090983ca (console_lock){+.+.}, at: vprintk_emit+0xdb/0x217
 #6: 00000000c743e583 (console_owner){-...}, at: console_unlock+0x211/0x60f
irq event stamp: 735222
__down_trylock_console_sem+0x4a/0x84
console_unlock+0x338/0x60f
__do_softirq+0x4a4/0x50d
irq_exit+0x64/0xe2
CPU: 2 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc5 #6
Hardware name: Google Caroline/Caroline, BIOS Google_Caroline.7820.286.0 03/15/2017
Call Trace:
 dump_stack+0x7d/0xbd
 ___might_sleep+0x238/0x259
 __pm_runtime_resume+0x4e/0xa4
 ? serial8250_rpm_get+0x2e/0x44
 serial8250_console_write+0x44/0x301
 ? lock_acquire+0x1b8/0x1fa
 console_unlock+0x577/0x60f
 vprintk_emit+0x1f0/0x217
 printk+0x52/0x6e
 register_console+0x43b/0x524
 uart_add_one_port+0x672/0x8b0
 ? set_io_from_upio+0x150/0x162
 serial8250_register_8250_port+0x825/0x8bb
 dw8250_probe+0x80c/0x8b0
 ? dw8250_serial_inq+0x8e/0x8e
 ? dw8250_check_lcr+0x108/0x108
 ? dw8250_runtime_resume+0x5b/0x5b
 ? dw8250_serial_outq+0xa1/0xa1
 ? dw8250_remove+0x115/0x115
 platform_drv_probe+0x76/0xc5
 really_probe+0x1f1/0x3ee
 ? driver_allows_async_probing+0x5d/0x5d
 driver_probe_device+0xd6/0x112
 ? driver_allows_async_probing+0x5d/0x5d
 bus_for_each_drv+0xbe/0xe5
 __device_attach+0xdd/0x15b
 bus_probe_device+0x5a/0x10b
 device_add+0x501/0x894
 ? _raw_write_unlock+0x27/0x3a
 platform_device_add+0x224/0x2b7
 mfd_add_device+0x718/0x75b
 ? __kmalloc+0x144/0x16a
 ? mfd_add_devices+0x38/0xdb
 mfd_add_devices+0x9b/0xdb
 intel_lpss_probe+0x7d4/0x8ee
 intel_lpss_pci_probe+0xac/0xd4
 pci_device_probe+0x101/0x18e
...

Revert the offending patch until a more comprehensive solution
is available.

Cc: Tony Lindgren <tony@atomide.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Phil Edworthy <phil.edworthy@renesas.com>
Fixes: d76c74387e1c ("serial: 8250_dw: Fix runtime PM handling")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
tty: Drop tty->count on tty_reopen() failure 2018-10-13T07:33:15+00:00 Dmitry Safonov dima@arista.com 2018-09-17T23:52:52+00:00 a09a553b1693a93c7da51245601ee9771653ac4b commit fe32416790093b31364c08395727de17ec96ace1 upstream. In case of tty_ldisc_reinit() failure, tty->count should be decremented back, otherwise we will never release_tty(). Tetsuo reported that it fixes noisy warnings on tty release like: pts pts4033: tty_release: tty->count(10529) != (#fd's(7) + #kopen's(0)) Fixes: commit 892d1fa7eaae ("tty: Destroy ldisc instance on hangup") Cc: stable@vger.kernel.org # v4.6+ Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.com> Reviewed-by: Jiri Slaby <jslaby@suse.cz> Tested-by: Jiri Slaby <jslaby@suse.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit fe32416790093b31364c08395727de17ec96ace1 upstream.

In case of tty_ldisc_reinit() failure, tty->count should be decremented
back, otherwise we will never release_tty().
Tetsuo reported that it fixes noisy warnings on tty release like:
  pts pts4033: tty_release: tty->count(10529) != (#fd's(7) + #kopen's(0))

Fixes: commit 892d1fa7eaae ("tty: Destroy ldisc instance on hangup")

Cc: stable@vger.kernel.org # v4.6+
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Reviewed-by: Jiri Slaby <jslaby@suse.cz>
Tested-by: Jiri Slaby <jslaby@suse.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: cpm_uart: return immediately from console poll 2018-10-03T23:59:18+00:00 Christophe Leroy christophe.leroy@c-s.fr 2018-09-14T10:32:50+00:00 98e1a83c338e4f3377c842ee7d60a5c36a30f0b3 commit be28c1e3ca29887e207f0cbcd294cefe5074bab6 upstream. kgdb expects poll function to return immediately and returning NO_POLL_CHAR when no character is available. Fixes: f5316b4aea024 ("kgdb,8250,pl011: Return immediately from console poll") Cc: Jason Wessel <jason.wessel@windriver.com> Cc: <stable@vger.kernel.org> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit be28c1e3ca29887e207f0cbcd294cefe5074bab6 upstream.

kgdb expects poll function to return immediately and
returning NO_POLL_CHAR when no character is available.

Fixes: f5316b4aea024 ("kgdb,8250,pl011: Return immediately from console poll")
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: mvebu-uart: Fix reporting of effective CSIZE to userspace 2018-10-03T23:59:18+00:00 Jan Kiszka jan.kiszka@siemens.com 2018-08-26T17:49:32+00:00 e91bf9073b44f3be71b80687a58e8fc1e8d25dd1 commit e0bf2d4982fe7d9ddaf550dd023803ea286f47fc upstream. Apparently, this driver (or the hardware) does not support character length settings. It's apparently running in 8-bit mode, but it makes userspace believe it's in 5-bit mode. That makes tcsetattr with CS8 incorrectly fail, breaking e.g. getty from busybox, thus the login shell on ttyMVx. Fix by hard-wiring CS8 into c_cflag. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Fixes: 30530791a7a0 ("serial: mvebu-uart: initial support for Armada-3700 serial port") Cc: stable <stable@vger.kernel.org> # 4.6+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit e0bf2d4982fe7d9ddaf550dd023803ea286f47fc upstream.

Apparently, this driver (or the hardware) does not support character
length settings. It's apparently running in 8-bit mode, but it makes
userspace believe it's in 5-bit mode. That makes tcsetattr with CS8
incorrectly fail, breaking e.g. getty from busybox, thus the login shell
on ttyMVx.

Fix by hard-wiring CS8 into c_cflag.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Fixes: 30530791a7a0 ("serial: mvebu-uart: initial support for Armada-3700 serial port")
Cc: stable <stable@vger.kernel.org> # 4.6+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: imx: restore handshaking irq for imx1 2018-10-03T23:59:17+00:00 Uwe Kleine-König u.kleine-koenig@pengutronix.de 2018-09-20T12:11:17+00:00 5d554763aaac8009646301fd14b05607ec01d965 commit 7e620984b62532783912312e334f3c48cdacbd5d upstream. Back in 2015 when irda was dropped from the driver imx1 was broken. This change reintroduces the support for the third interrupt of the UART. Fixes: afe9cbb1a6ad ("serial: imx: drop support for IRDA") Cc: stable <stable@vger.kernel.org> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Leonard Crestez <leonard.crestez@nxp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 7e620984b62532783912312e334f3c48cdacbd5d upstream.

Back in 2015 when irda was dropped from the driver imx1 was broken. This
change reintroduces the support for the third interrupt of the UART.

Fixes: afe9cbb1a6ad ("serial: imx: drop support for IRDA")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty: serial: lpuart: avoid leaking struct tty_struct 2018-10-03T23:59:17+00:00 Stefan Agner stefan@agner.ch 2018-08-28T10:44:24+00:00 98ecfdf49ff73c87a5ab8fa7ba1f22db67da6f29 commit 3216c622a24b0ebb9c159a8d1daf7f17a106b3f5 upstream. The function tty_port_tty_get() gets a reference to the tty. Since the code is not using tty_port_tty_set(), the reference is kept even after closing the tty. Avoid using tty_port_tty_get() by directly access the tty instance. Since lpuart_start_rx_dma() is called from the .startup() and .set_termios() callback, it is safe to assume the tty instance is valid. Cc: stable@vger.kernel.org # v4.9+ Fixes: 5887ad43ee02 ("tty: serial: fsl_lpuart: Use cyclic DMA for Rx") Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 3216c622a24b0ebb9c159a8d1daf7f17a106b3f5 upstream.

The function tty_port_tty_get() gets a reference to the tty. Since
the code is not using tty_port_tty_set(), the reference is kept
even after closing the tty.

Avoid using tty_port_tty_get() by directly access the tty instance.
Since lpuart_start_rx_dma() is called from the .startup() and
.set_termios() callback, it is safe to assume the tty instance is
valid.

Cc: stable@vger.kernel.org # v4.9+
Fixes: 5887ad43ee02 ("tty: serial: fsl_lpuart: Use cyclic DMA for Rx")
Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: pxa: Fix an error handling path in 'serial_pxa_probe()' 2018-10-03T23:59:11+00:00 Christophe JAILLET christophe.jaillet@wanadoo.fr 2018-06-11T17:30:35+00:00 7a887d2a1f91b8a0856735ddc8bf6d38b06e2b5a [ Upstream commit 95a0e656580fab3128c7bee5f660c50784f53651 ] If port.line is out of range, we still need to release some resources, or we will leak them. Fixes: afc7851fab83 ("serial: pxa: Fix out-of-bounds access through serial port index") Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 95a0e656580fab3128c7bee5f660c50784f53651 ]

If port.line is out of range, we still need to release some resources, or
we will leak them.

Fixes: afc7851fab83 ("serial: pxa: Fix out-of-bounds access through serial port index")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/tty: add error handling for pcmcia_loop_config 2018-10-03T23:59:11+00:00 Zhouyang Jia jiazhouyang09@gmail.com 2018-06-12T04:36:25+00:00 e65f712ea9369fcb7c1824d3eaa6dd19caa22482 [ Upstream commit 85c634e919bd6ef17427f26a52920aeba12e16ee ] When pcmcia_loop_config fails, the lack of error-handling code may cause unexpected results. This patch adds error-handling code after calling pcmcia_loop_config. Signed-off-by: Zhouyang Jia <jiazhouyang09@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 85c634e919bd6ef17427f26a52920aeba12e16ee ]

When pcmcia_loop_config fails, the lack of error-handling code may
cause unexpected results.

This patch adds error-handling code after calling pcmcia_loop_config.

Signed-off-by: Zhouyang Jia <jiazhouyang09@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: sh-sci: Stop RX FIFO timer during port shutdown 2018-10-03T23:59:04+00:00 Geert Uytterhoeven geert+renesas@glider.be 2018-07-06T09:08:36+00:00 cb39b07bf5f961eb1c5d29bf5d392b9f3461f7e2 [ Upstream commit c5a9262fa8bfed0dddc7466ef10fcd292e2af61b ] The RX FIFO timer may be armed when the port is shut down, hence the timer function may still be called afterwards. Fix this race condition by deleting the timer during port shutdown. Fixes: 039403765e5da3c6 ("serial: sh-sci: SCIFA/B RX FIFO software timeout") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit c5a9262fa8bfed0dddc7466ef10fcd292e2af61b ]

The RX FIFO timer may be armed when the port is shut down, hence the
timer function may still be called afterwards.

Fix this race condition by deleting the timer during port shutdown.

Fixes: 039403765e5da3c6 ("serial: sh-sci: SCIFA/B RX FIFO software timeout")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>