linux-stable.git/drivers/tty/serial, branch v6.9.4 Linux kernel stable tree serial: sh-sci: protect invalidating RXDMA on shutdown 2024-06-12T09:39:21+00:00 Wolfram Sang wsa+renesas@sang-engineering.com 2024-05-06T11:40:17+00:00 5172196474c25ec716ebac069e93bfa3bcf3015c [ Upstream commit aae20f6e34cd0cbd67a1d0e5877561c40109a81b ] The to-be-fixed commit removed locking when invalidating the DMA RX descriptors on shutdown. It overlooked that there is still a rx_timer running which may still access the protected data. So, re-add the locking. Reported-by: Dirk Behme <dirk.behme@de.bosch.com> Closes: https://lore.kernel.org/r/ee6c9e16-9f29-450e-81da-4a8dceaa8fc7@de.bosch.com Fixes: 2c4ee23530ff ("serial: sh-sci: Postpone DMA release when falling back to PIO") Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Link: https://lore.kernel.org/r/20240506114016.30498-7-wsa+renesas@sang-engineering.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit aae20f6e34cd0cbd67a1d0e5877561c40109a81b ]

The to-be-fixed commit removed locking when invalidating the DMA RX
descriptors on shutdown. It overlooked that there is still a rx_timer
running which may still access the protected data. So, re-add the
locking.

Reported-by: Dirk Behme <dirk.behme@de.bosch.com>
Closes: https://lore.kernel.org/r/ee6c9e16-9f29-450e-81da-4a8dceaa8fc7@de.bosch.com
Fixes: 2c4ee23530ff ("serial: sh-sci: Postpone DMA release when falling back to PIO")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20240506114016.30498-7-wsa+renesas@sang-engineering.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
serial: sc16is7xx: add proper sched.h include for sched_set_fifo() 2024-06-12T09:39:09+00:00 Hugo Villeneuve hvilleneuve@dimonoff.com 2024-04-09T15:42:49+00:00 312a665650024a59239b623e2debd7a9e5df83ef [ Upstream commit 2a8e4ab0c93fad30769479f86849e22d63cd0e12 ] Replace incorrect include with the proper one for sched_set_fifo() declaration. Fixes: 28d2f209cd16 ("sched,serial: Convert to sched_set_fifo()") Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Link: https://lore.kernel.org/r/20240409154253.3043822-2-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 2a8e4ab0c93fad30769479f86849e22d63cd0e12 ]

Replace incorrect include with the proper one for sched_set_fifo()
declaration.

Fixes: 28d2f209cd16 ("sched,serial: Convert to sched_set_fifo()")
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20240409154253.3043822-2-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
serial: max3100: Fix bitwise types 2024-06-12T09:39:09+00:00 Andy Shevchenko andriy.shevchenko@linux.intel.com 2024-04-02T19:50:30+00:00 daae076ae946612b19e706d0b2ef3e091c1f4eea [ Upstream commit e60955dbecb97f080848a57524827e2db29c70fd ] Sparse is not happy about misuse of bitwise types: .../max3100.c:194:13: warning: incorrect type in assignment (different base types) .../max3100.c:194:13: expected unsigned short [addressable] [usertype] etx .../max3100.c:194:13: got restricted __be16 [usertype] .../max3100.c:202:15: warning: cast to restricted __be16 Fix this by choosing proper types for the respective variables. Fixes: 7831d56b0a35 ("tty: MAX3100") Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20240402195306.269276-4-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit e60955dbecb97f080848a57524827e2db29c70fd ]

Sparse is not happy about misuse of bitwise types:

  .../max3100.c:194:13: warning: incorrect type in assignment (different base types)
  .../max3100.c:194:13:    expected unsigned short [addressable] [usertype] etx
  .../max3100.c:194:13:    got restricted __be16 [usertype]
  .../max3100.c:202:15: warning: cast to restricted __be16

Fix this by choosing proper types for the respective variables.

Fixes: 7831d56b0a35 ("tty: MAX3100")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240402195306.269276-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
serial: max3100: Update uart_driver_registered on driver removal 2024-06-12T09:39:08+00:00 Andy Shevchenko andriy.shevchenko@linux.intel.com 2024-04-02T19:50:29+00:00 fa84ca78b048dfb00df0ef446f5c35e0a98ca6a0 [ Upstream commit 712a1fcb38dc7cac6da63ee79a88708fbf9c45ec ] The removal of the last MAX3100 device triggers the removal of the driver. However, code doesn't update the respective global variable and after insmod — rmmod — insmod cycle the kernel oopses: max3100 spi-PRP0001:01: max3100_probe: adding port 0 BUG: kernel NULL pointer dereference, address: 0000000000000408 ... RIP: 0010:serial_core_register_port+0xa0/0x840 ... max3100_probe+0x1b6/0x280 [max3100] spi_probe+0x8d/0xb0 Update the actual state so next time UART driver will be registered again. Hugo also noticed, that the error path in the probe also affected by having the variable set, and not cleared. Instead of clearing it move the assignment after the successfull uart_register_driver() call. Fixes: 7831d56b0a35 ("tty: MAX3100") Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Link: https://lore.kernel.org/r/20240402195306.269276-3-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 712a1fcb38dc7cac6da63ee79a88708fbf9c45ec ]

The removal of the last MAX3100 device triggers the removal of
the driver. However, code doesn't update the respective global
variable and after insmod — rmmod — insmod cycle the kernel
oopses:

  max3100 spi-PRP0001:01: max3100_probe: adding port 0
  BUG: kernel NULL pointer dereference, address: 0000000000000408
  ...
  RIP: 0010:serial_core_register_port+0xa0/0x840
  ...
   max3100_probe+0x1b6/0x280 [max3100]
   spi_probe+0x8d/0xb0

Update the actual state so next time UART driver will be registered
again.

Hugo also noticed, that the error path in the probe also affected
by having the variable set, and not cleared. Instead of clearing it
move the assignment after the successfull uart_register_driver() call.

Fixes: 7831d56b0a35 ("tty: MAX3100")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20240402195306.269276-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
serial: max3100: Lock port->lock when calling uart_handle_cts_change() 2024-06-12T09:39:08+00:00 Andy Shevchenko andriy.shevchenko@linux.intel.com 2024-04-02T19:50:28+00:00 865b30c8661924ee9145f442bf32cea549faa869 [ Upstream commit 77ab53371a2066fdf9b895246505f5ef5a4b5d47 ] uart_handle_cts_change() has to be called with port lock taken, Since we run it in a separate work, the lock may not be taken at the time of running. Make sure that it's taken by explicitly doing that. Without it we got a splat: WARNING: CPU: 0 PID: 10 at drivers/tty/serial/serial_core.c:3491 uart_handle_cts_change+0xa6/0xb0 ... Workqueue: max3100-0 max3100_work [max3100] RIP: 0010:uart_handle_cts_change+0xa6/0xb0 ... max3100_handlerx+0xc5/0x110 [max3100] max3100_work+0x12a/0x340 [max3100] Fixes: 7831d56b0a35 ("tty: MAX3100") Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20240402195306.269276-2-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 77ab53371a2066fdf9b895246505f5ef5a4b5d47 ]

uart_handle_cts_change() has to be called with port lock taken,
Since we run it in a separate work, the lock may not be taken at
the time of running. Make sure that it's taken by explicitly doing
that. Without it we got a splat:

  WARNING: CPU: 0 PID: 10 at drivers/tty/serial/serial_core.c:3491 uart_handle_cts_change+0xa6/0xb0
  ...
  Workqueue: max3100-0 max3100_work [max3100]
  RIP: 0010:uart_handle_cts_change+0xa6/0xb0
  ...
   max3100_handlerx+0xc5/0x110 [max3100]
   max3100_work+0x12a/0x340 [max3100]

Fixes: 7831d56b0a35 ("tty: MAX3100")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240402195306.269276-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
serial: 8520_mtk: Set RTS on shutdown for Rx in-band wakeup 2024-05-30T07:43:59+00:00 Pin-yen Lin treapking@chromium.org 2024-04-24T12:58:08+00:00 1f97ccd2c32ad8f0322e4fe3a291a61e509b3e5e commit 4244f830a56058ee0670d80e7ac9fd7c982eb480 upstream. When Rx in-band wakeup is enabled, set RTS to true in mtk8250_shutdown() so the connected device can still send message and trigger IRQ when the system is suspended. Fixes: 18c9d4a3c249 ("serial: When UART is suspended, set RTS to false") Cc: stable <stable@kernel.org> Signed-off-by: Pin-yen Lin <treapking@chromium.org> Link: https://lore.kernel.org/r/20240424130619.2924456-1-treapking@chromium.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 4244f830a56058ee0670d80e7ac9fd7c982eb480 upstream.

When Rx in-band wakeup is enabled, set RTS to true in mtk8250_shutdown()
so the connected device can still send message and trigger IRQ when the
system is suspended.

Fixes: 18c9d4a3c249 ("serial: When UART is suspended, set RTS to false")
Cc: stable <stable@kernel.org>
Signed-off-by: Pin-yen Lin <treapking@chromium.org>
Link: https://lore.kernel.org/r/20240424130619.2924456-1-treapking@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: 8250_bcm7271: use default_mux_rate if possible 2024-05-30T07:43:59+00:00 Doug Berger opendmb@gmail.com 2024-04-24T22:25:59+00:00 f98bc68a3244beacf8092977782462429638d6eb commit 614a19b89ca43449196a8af1afac7d55c6781687 upstream. There is a scenario when resuming from some power saving states with no_console_suspend where console output can be generated before the 8250_bcm7271 driver gets the opportunity to restore the baud_mux_clk frequency. Since the baud_mux_clk is at its default frequency at this time the output can be garbled until the driver gets the opportunity to resume. Since this is only an issue with console use of the serial port during that window and the console isn't likely to use baud rates that require alternate baud_mux_clk frequencies, allow the driver to select the default_mux_rate if it is accurate enough. Fixes: 41a469482de2 ("serial: 8250: Add new 8250-core based Broadcom STB driver") Cc: stable@vger.kernel.org Signed-off-by: Doug Berger <opendmb@gmail.com> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com> Tested-by: Florian Fainelli <florian.fainelli@broadcom.com> Link: https://lore.kernel.org/r/20240424222559.1844045-1-opendmb@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 614a19b89ca43449196a8af1afac7d55c6781687 upstream.

There is a scenario when resuming from some power saving states
with no_console_suspend where console output can be generated
before the 8250_bcm7271 driver gets the opportunity to restore
the baud_mux_clk frequency. Since the baud_mux_clk is at its
default frequency at this time the output can be garbled until
the driver gets the opportunity to resume.

Since this is only an issue with console use of the serial port
during that window and the console isn't likely to use baud
rates that require alternate baud_mux_clk frequencies, allow the
driver to select the default_mux_rate if it is accurate enough.

Fixes: 41a469482de2 ("serial: 8250: Add new 8250-core based Broadcom STB driver")
Cc: stable@vger.kernel.org
Signed-off-by: Doug Berger <opendmb@gmail.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Tested-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://lore.kernel.org/r/20240424222559.1844045-1-opendmb@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: sc16is7xx: fix bug in sc16is7xx_set_baud() when using prescaler 2024-05-30T07:43:59+00:00 Hugo Villeneuve hvilleneuve@dimonoff.com 2024-04-30T20:04:30+00:00 671202e86739557e5612c132883c0246e02655cc commit 8492bd91aa055907c67ef04f2b56f6dadd1f44bf upstream. When using a high speed clock with a low baud rate, the 4x prescaler is automatically selected if required. In that case, sc16is7xx_set_baud() properly configures the chip registers, but returns an incorrect baud rate by not taking into account the prescaler value. This incorrect baud rate is then fed to uart_update_timeout(). For example, with an input clock of 80MHz, and a selected baud rate of 50, sc16is7xx_set_baud() will return 200 instead of 50. Fix this by first changing the prescaler variable to hold the selected prescaler value instead of the MCR bitfield. Then properly take into account the selected prescaler value in the return value computation. Also add better documentation about the divisor value computation. Fixes: dfeae619d781 ("serial: sc16is7xx") Cc: stable@vger.kernel.org Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20240430200431.4102923-1-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 8492bd91aa055907c67ef04f2b56f6dadd1f44bf upstream.

When using a high speed clock with a low baud rate, the 4x prescaler is
automatically selected if required. In that case, sc16is7xx_set_baud()
properly configures the chip registers, but returns an incorrect baud
rate by not taking into account the prescaler value. This incorrect baud
rate is then fed to uart_update_timeout().

For example, with an input clock of 80MHz, and a selected baud rate of 50,
sc16is7xx_set_baud() will return 200 instead of 50.

Fix this by first changing the prescaler variable to hold the selected
prescaler value instead of the MCR bitfield. Then properly take into
account the selected prescaler value in the return value computation.

Also add better documentation about the divisor value computation.

Fixes: dfeae619d781 ("serial: sc16is7xx")
Cc: stable@vger.kernel.org
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240430200431.4102923-1-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: kgdboc: Fix NMI-safety problems from keyboard reset code 2024-05-25T14:30:55+00:00 Daniel Thompson daniel.thompson@linaro.org 2024-04-24T14:21:41+00:00 4dd04367a26a48e6b0750322c0c0423a77902858 commit b2aba15ad6f908d1a620fd97f6af5620c3639742 upstream. Currently, when kdb is compiled with keyboard support, then we will use schedule_work() to provoke reset of the keyboard status. Unfortunately schedule_work() gets called from the kgdboc post-debug-exception handler. That risks deadlock since schedule_work() is not NMI-safe and, even on platforms where the NMI is not directly used for debugging, the debug trap can have NMI-like behaviour depending on where breakpoints are placed. Fix this by using the irq work system, which is NMI-safe, to defer the call to schedule_work() to a point when it is safe to call. Reported-by: Liuye <liu.yeC@h3c.com> Closes: https://lore.kernel.org/all/20240228025602.3087748-1-liu.yeC@h3c.com/ Cc: stable@vger.kernel.org Reviewed-by: Douglas Anderson <dianders@chromium.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20240424-kgdboc_fix_schedule_work-v2-1-50f5a490aec5@linaro.org Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit b2aba15ad6f908d1a620fd97f6af5620c3639742 upstream.

Currently, when kdb is compiled with keyboard support, then we will use
schedule_work() to provoke reset of the keyboard status.  Unfortunately
schedule_work() gets called from the kgdboc post-debug-exception
handler.  That risks deadlock since schedule_work() is not NMI-safe and,
even on platforms where the NMI is not directly used for debugging, the
debug trap can have NMI-like behaviour depending on where breakpoints
are placed.

Fix this by using the irq work system, which is NMI-safe, to defer the
call to schedule_work() to a point when it is safe to call.

Reported-by: Liuye <liu.yeC@h3c.com>
Closes: https://lore.kernel.org/all/20240228025602.3087748-1-liu.yeC@h3c.com/
Cc: stable@vger.kernel.org
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20240424-kgdboc_fix_schedule_work-v2-1-50f5a490aec5@linaro.org
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: stm32: Reset .throttled state in .startup() 2024-04-17T11:26:45+00:00 Uwe Kleine-König u.kleine-koenig@pengutronix.de 2024-04-17T09:03:28+00:00 ea2624b5b829b8f93c0dce25721d835969b34faf When an UART is opened that still has .throttled set from a previous open, the RX interrupt is enabled but the irq handler doesn't consider it. This easily results in a stuck irq with the effect to occupy the CPU in a tight loop. So reset the throttle state in .startup() to ensure that RX irqs are handled. Fixes: d1ec8a2eabe9 ("serial: stm32: update throttle and unthrottle ops for dma mode") Cc: stable@vger.kernel.org Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/a784f80d3414f7db723b2ec66efc56e1ad666cbf.1713344161.git.u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
When an UART is opened that still has .throttled set from a previous
open, the RX interrupt is enabled but the irq handler doesn't consider
it. This easily results in a stuck irq with the effect to occupy the CPU
in a tight loop.

So reset the throttle state in .startup() to ensure that RX irqs are
handled.

Fixes: d1ec8a2eabe9 ("serial: stm32: update throttle and unthrottle ops for dma mode")
Cc: stable@vger.kernel.org
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/a784f80d3414f7db723b2ec66efc56e1ad666cbf.1713344161.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>