linux-stable.git/drivers/tty/serial/serial_core.c, branch linux-6.4.y Linux kernel stable tree serial: core: lock port for start_rx() in uart_resume_port() 2023-07-19T14:36:32+00:00 John Ogness john.ogness@linutronix.de 2023-05-25T09:31:55+00:00 ce73b6f8d92d91dbdce315a685c85f880543d1d8 [ Upstream commit 51e45fba14bf08b66bca764a083c7f2e2ff62f01 ] The only user of the start_rx() callback (qcom_geni) directly calls its own stop_rx() callback. Since stop_rx() requires that the port->lock is taken and interrupts are disabled, the start_rx() callback has the same requirement. Fixes: cfab87c2c271 ("serial: core: Introduce callback for start_rx and do stop_rx in suspend only if this callback implementation is present.") Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Douglas Anderson <dianders@chromium.org> Link: https://lore.kernel.org/r/20230525093159.223817-5-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 51e45fba14bf08b66bca764a083c7f2e2ff62f01 ]

The only user of the start_rx() callback (qcom_geni) directly calls
its own stop_rx() callback. Since stop_rx() requires that the
port->lock is taken and interrupts are disabled, the start_rx()
callback has the same requirement.

Fixes: cfab87c2c271 ("serial: core: Introduce callback for start_rx and do stop_rx in suspend only if this callback implementation is present.")
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20230525093159.223817-5-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
serial: core: lock port for stop_rx() in uart_suspend_port() 2023-07-19T14:36:32+00:00 John Ogness john.ogness@linutronix.de 2023-05-25T09:31:53+00:00 ece78f66a948741b1b0bca6536285fa6a74b9cc2 [ Upstream commit abcb0cf1f5b2d99b1d117a4dbce334120e358d6d ] The uarts_ops stop_rx() callback expects that the port->lock is taken and interrupts are disabled. Fixes: c9d2325cdb92 ("serial: core: Do stop_rx in suspend path for console if console_suspend is disabled") Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Douglas Anderson <dianders@chromium.org> Link: https://lore.kernel.org/r/20230525093159.223817-3-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit abcb0cf1f5b2d99b1d117a4dbce334120e358d6d ]

The uarts_ops stop_rx() callback expects that the port->lock is
taken and interrupts are disabled.

Fixes: c9d2325cdb92 ("serial: core: Do stop_rx in suspend path for console if console_suspend is disabled")
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20230525093159.223817-3-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
serial: core: Disable uart_start() on uart_remove_one_port() 2023-04-20T11:43:44+00:00 Tony Lindgren tony@atomide.com 2023-04-19T11:54:22+00:00 63f4c34561718a349d321105adab028cbf212d57 While rebinding a uart device in a loop I noticed we may see a tx related race on uart_remove_one_port(): uart_write from n_tty_write n_tty_write from file_tty_write.constprop.0 file_tty_write.constprop.0 from vfs_write vfs_write from ksys_write ksys_write from ret_fast_syscall Let's disallow tx on port->UPF_DEAD. This flag gets set before we start tearing down the port in uart_remove_one_port(). Signed-off-by: Tony Lindgren <tony@atomide.com> Link: https://lore.kernel.org/r/20230419115423.59957-1-tony@atomide.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
While rebinding a uart device in a loop I noticed we may see a tx related
race on uart_remove_one_port():

uart_write from n_tty_write
n_tty_write from file_tty_write.constprop.0
file_tty_write.constprop.0 from vfs_write
vfs_write from ksys_write
ksys_write from ret_fast_syscall

Let's disallow tx on port->UPF_DEAD. This flag gets set before we start
tearing down the port in uart_remove_one_port().

Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20230419115423.59957-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: fix TIOCSRS485 locking 2023-04-20T11:42:24+00:00 Johan Hovold johan@kernel.org 2023-04-12T12:48:11+00:00 9e4f2a8004213339e9d837d891a59cc80e082966 The RS485 multipoint addressing support for some reason added a new ADDRB termios cflag which is (only!) updated from one of the RS485 ioctls. Make sure to take the termios rw semaphore for the right ioctl (i.e. set, not get). Fixes: ae50bb275283 ("serial: take termios_rwsem for ->rs485_config() & pass termios as param") Cc: stable@vger.kernel.org # 6.0 Cc: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20230412124811.11217-1-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
The RS485 multipoint addressing support for some reason added a new
ADDRB termios cflag which is (only!) updated from one of the RS485
ioctls.

Make sure to take the termios rw semaphore for the right ioctl (i.e.
set, not get).

Fixes: ae50bb275283 ("serial: take termios_rwsem for ->rs485_config() & pass termios as param")
Cc: stable@vger.kernel.org	# 6.0
Cc: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20230412124811.11217-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: uart_poll_init() should power on the UART 2023-03-29T08:51:52+00:00 Douglas Anderson dianders@chromium.org 2023-03-16T20:20:56+00:00 5e227ef2aa388f14ceeafa65eb8a38fa37918eb4 On Qualcomm devices which use the "geni" serial driver, kdb/kgdb won't be very happy if you use it but the resources of the port haven't been powered on. Today kdb/kgdb rely on someone else powering the port on. This could be the normal kernel console or an agetty running. Let's fix this to explicitly power things on when setting up a polling driver. Signed-off-by: Douglas Anderson <dianders@chromium.org> Link: https://lore.kernel.org/r/20230316132027.RESEND.1.I106c39498d8094c6f5e7ada42c7db17aa5c64e48@changeid Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
On Qualcomm devices which use the "geni" serial driver, kdb/kgdb won't
be very happy if you use it but the resources of the port haven't been
powered on. Today kdb/kgdb rely on someone else powering the port
on. This could be the normal kernel console or an agetty running.
Let's fix this to explicitly power things on when setting up a polling
driver.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20230316132027.RESEND.1.I106c39498d8094c6f5e7ada42c7db17aa5c64e48@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: Remove uart_wait_until_sent() forward declaration 2023-03-17T14:00:40+00:00 Ilpo Järvinen ilpo.jarvinen@linux.intel.com 2023-03-09T08:09:23+00:00 044498cd89a1a580a3145b2c5fb34d5e2f3b9908 Remove unnecessary forward declaration of uart_wait_until_sent(). Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20230309080923.11778-9-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Remove unnecessary forward declaration of uart_wait_until_sent().

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230309080923.11778-9-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: Rename hw_stopped to old_hw_stopped & improve logic 2023-03-17T14:00:40+00:00 Ilpo Järvinen ilpo.jarvinen@linux.intel.com 2023-03-09T08:09:22+00:00 1690ca513da18b1f7de89c39faf78278d302b867 hw_stopped in uart_change_line_settings() stores old hw_stopped, thus rename it appropriately. Alter logic to check first if the hw_stopped was changed, and then pick which function to call if it was because the logic is more obvious that way. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20230309080923.11778-8-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
hw_stopped in uart_change_line_settings() stores old hw_stopped, thus
rename it appropriately.

Alter logic to check first if the hw_stopped was changed, and then pick
which function to call if it was because the logic is more obvious that
way.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230309080923.11778-8-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: Make hw_stopped bool 2023-03-17T14:00:40+00:00 Ilpo Järvinen ilpo.jarvinen@linux.intel.com 2023-03-09T08:09:21+00:00 b5def43a7b3e7e68d6b49a23166f8b886a26bb54 Convert hw_stopped in uart_port to bool because its more appropriate type for how it is used. Also convert the local variable in uart_change_line_settings() caching old hw_stopped to bool. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20230309080923.11778-7-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Convert hw_stopped in uart_port to bool because its more appropriate
type for how it is used.

Also convert the local variable in uart_change_line_settings() caching
old hw_stopped to bool.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230309080923.11778-7-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: Rename uart_change_speed() to uart_change_line_settings() 2023-03-17T14:00:40+00:00 Ilpo Järvinen ilpo.jarvinen@linux.intel.com 2023-03-09T08:09:20+00:00 826736a6c7c8c3185bfb10e03c10d03d53d6cf94 uart_change_speed() changes more than just speed so rename it to more generic uart_change_line_settings(). Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20230309080923.11778-6-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
uart_change_speed() changes more than just speed so rename it to more
generic uart_change_line_settings().

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230309080923.11778-6-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: Move uart_change_speed() earlier 2023-03-17T14:00:40+00:00 Ilpo Järvinen ilpo.jarvinen@linux.intel.com 2023-03-09T08:09:19+00:00 8e90cf29aef77b59ed6a6f6466add2af79621f26 Move uart_change_speed() earlier to get rid of its forward declaration. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20230309080923.11778-5-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Move uart_change_speed() earlier to get rid of its forward declaration.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230309080923.11778-5-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>