6220 Commits

Author SHA1 Message Date
Ilpo Järvinen
32a7f06451 serial: 8250: Flush DMA Rx on RLSI
commit 1980860e0c8299316cddaf0992dd9e1258ec9d88 upstream.

Returning true from handle_rx_dma() without flushing DMA first creates
a data ordering hazard. If DMA Rx has handled any character at the
point when RLSI occurs, the non-DMA path handles any pending characters
jumping them ahead of those characters that are pending under DMA.

Fixes: 75df022b5f89 ("serial: 8250_dma: Fix RX handling")
Cc: <stable@vger.kernel.org>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20221108121952.5497-5-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-25 17:42:20 +01:00
Ilpo Järvinen
89c0c27ab3 serial: 8250_lpss: Configure DMA also w/o DMA filter
commit 1bfcbe5805d0cfc83c3544dcd01e0a282c1f6790 upstream.

If the platform doesn't use DMA device filter (as is the case with
Elkhart Lake), whole lpss8250_dma_setup() setup is skipped. This
results in skipping also *_maxburst setup which is undesirable.
Refactor lpss8250_dma_setup() to configure DMA even if filter is not
setup.

Cc: stable <stable@kernel.org>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20221108121952.5497-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-25 17:42:19 +01:00
Ilpo Järvinen
d6ebe11ad3 serial: 8250: Fall back to non-DMA Rx if IIR_RDI occurs
commit a931237cbea256aff13bb403da13a97b2d1605d9 upstream.

DW UART sometimes triggers IIR_RDI during DMA Rx when IIR_RX_TIMEOUT
should have been triggered instead. Since IIR_RDI has higher priority
than IIR_RX_TIMEOUT, this causes the Rx to hang into interrupt loop.
The problem seems to occur at least with some combinations of
small-sized transfers (I've reproduced the problem on Elkhart Lake PSE
UARTs).

If there's already an on-going Rx DMA and IIR_RDI triggers, fall
graciously back to non-DMA Rx. That is, behave as if IIR_RX_TIMEOUT had
occurred.

8250_omap already considers IIR_RDI similar to this change so its
nothing unheard of.

Fixes: 75df022b5f89 ("serial: 8250_dma: Fix RX handling")
Cc: <stable@vger.kernel.org>
Co-developed-by: Srikanth Thokala <srikanth.thokala@intel.com>
Signed-off-by: Srikanth Thokala <srikanth.thokala@intel.com>
Co-developed-by: Aman Kumar <aman.kumar@intel.com>
Signed-off-by: Aman Kumar <aman.kumar@intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20221108121952.5497-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-25 17:42:19 +01:00
Duoming Zhou
b768afc68b tty: n_gsm: fix sleep-in-atomic-context bug in gsm_control_send
[ Upstream commit 7b7dfe4833c70a11cdfa51b38705103bd31eddaa ]

The function gsm_dlci_t1() is a timer handler that runs in an
atomic context, but it calls "kzalloc(..., GFP_KERNEL)" that
may sleep. As a result, the sleep-in-atomic-context bug will
happen. The process is shown below:

gsm_dlci_t1()
 gsm_dlci_open()
  gsm_modem_update()
   gsm_modem_upd_via_msc()
    gsm_control_send()
     kzalloc(sizeof(.., GFP_KERNEL) //may sleep

This patch changes the gfp_t parameter of kzalloc() from GFP_KERNEL to
GFP_ATOMIC in order to mitigate the bug.

Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Link: https://lore.kernel.org/r/20221002040709.27849-1-duoming@zju.edu.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-25 17:42:14 +01:00
Shawn Guo
476b09e07b serial: imx: Add missing .thaw_noirq hook
[ Upstream commit 4561d8008a467cb05ac632a215391d6b787f40aa ]

The following warning is seen with non-console UART instance when
system hibernates.

[   37.371969] ------------[ cut here ]------------
[   37.376599] uart3_root_clk already disabled
[   37.380810] WARNING: CPU: 0 PID: 296 at drivers/clk/clk.c:952 clk_core_disable+0xa4/0xb0
...
[   37.506986] Call trace:
[   37.509432]  clk_core_disable+0xa4/0xb0
[   37.513270]  clk_disable+0x34/0x50
[   37.516672]  imx_uart_thaw+0x38/0x5c
[   37.520250]  platform_pm_thaw+0x30/0x6c
[   37.524089]  dpm_run_callback.constprop.0+0x3c/0xd4
[   37.528972]  device_resume+0x7c/0x160
[   37.532633]  dpm_resume+0xe8/0x230
[   37.536036]  hibernation_snapshot+0x288/0x430
[   37.540397]  hibernate+0x10c/0x2e0
[   37.543798]  state_store+0xc4/0xd0
[   37.547203]  kobj_attr_store+0x1c/0x30
[   37.550953]  sysfs_kf_write+0x48/0x60
[   37.554619]  kernfs_fop_write_iter+0x118/0x1ac
[   37.559063]  new_sync_write+0xe8/0x184
[   37.562812]  vfs_write+0x230/0x290
[   37.566214]  ksys_write+0x68/0xf4
[   37.569529]  __arm64_sys_write+0x20/0x2c
[   37.573452]  invoke_syscall.constprop.0+0x50/0xf0
[   37.578156]  do_el0_svc+0x11c/0x150
[   37.581648]  el0_svc+0x30/0x140
[   37.584792]  el0t_64_sync_handler+0xe8/0xf0
[   37.588976]  el0t_64_sync+0x1a0/0x1a4
[   37.592639] ---[ end trace 56e22eec54676d75 ]---

On hibernating, pm core calls into related hooks in sequence like:

    .freeze
    .freeze_noirq
    .thaw_noirq
    .thaw

With .thaw_noirq hook being absent, the clock will be disabled in a
unbalanced call which results the warning above.

    imx_uart_freeze()
        clk_prepare_enable()
    imx_uart_suspend_noirq()
        clk_disable()
    imx_uart_thaw
        clk_disable_unprepare()

Adding the missing .thaw_noirq hook as imx_uart_resume_noirq() will have
the call sequence corrected as below and thus fix the warning.

    imx_uart_freeze()
        clk_prepare_enable()
    imx_uart_suspend_noirq()
        clk_disable()
    imx_uart_resume_noirq()
        clk_enable()
    imx_uart_thaw
        clk_disable_unprepare()

Fixes: 09df0b3464e5 ("serial: imx: fix endless loop during suspend")
Reviewed-by: Martin Kaiser <martin@kaiser.cx>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Link: https://lore.kernel.org/r/20221012121353.2346280-1-shawn.guo@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-25 17:42:14 +01:00
Tony Lindgren
b7c6033a8f serial: 8250: omap: Flush PM QOS work on remove
[ Upstream commit d0b68629bd2fb61e0171a62f2e8da3db322f5cf6 ]

Rebinding 8250_omap in a loop will at some point produce a warning for
kernel/power/qos.c:296 cpu_latency_qos_update_request() with error
"cpu_latency_qos_update_request called for unknown object". Let's flush
the possibly pending PM QOS work scheduled from omap8250_runtime_suspend()
before we disable runtime PM.

Fixes: 61929cf0169d ("tty: serial: Add 8250-core based omap driver")
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20221028110044.54719-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-25 17:42:14 +01:00
Tony Lindgren
2d66412563 serial: 8250: omap: Fix unpaired pm_runtime_put_sync() in omap8250_remove()
[ Upstream commit e3f0c638f428fd66b5871154b62706772045f91a ]

On remove, we get an error for "Runtime PM usage count underflow!". I guess
this driver is mostly built-in, and this issue has gone unnoticed for a
while. Somehow I did not catch this issue with my earlier fix done with
commit 4e0f5cc65098 ("serial: 8250_omap: Fix probe and remove for PM
runtime").

Fixes: 4e0f5cc65098 ("serial: 8250_omap: Fix probe and remove for PM runtime")
Signed-off-by: Tony Lindgren <tony@atomide.com>
Depends-on: dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter")
Link: https://lore.kernel.org/r/20221028105813.54290-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-25 17:42:13 +01:00
Matthias Schiffer
747e76f4cc serial: 8250_omap: remove wait loop from Errata i202 workaround
[ Upstream commit e828e56684d61b17317e0cfdef83791fa61cb76b ]

We were occasionally seeing the "Errata i202: timedout" on an AM335x
board when repeatedly opening and closing a UART connected to an active
sender. As new input may arrive at any time, it is possible to miss the
"RX FIFO empty" condition, forcing the loop to wait until it times out.

Nothing in the i202 Advisory states that such a wait is even necessary;
other FIFO clear functions like serial8250_clear_fifos() do not wait
either. For this reason, it seems safe to remove the wait, fixing the
mentioned issue.

Fixes: 61929cf0169d ("tty: serial: Add 8250-core based omap driver")
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Link: https://lore.kernel.org/r/20221013112339.2540767-1-matthias.schiffer@ew.tq-group.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-25 17:42:13 +01:00
Helge Deller
506ae30167 parisc: Make 8250_gsc driver dependend on CONFIG_PARISC
commit e8a18e3f00f3ee8d07c17ab1ea3ad4df4a3b6fe0 upstream.

Although the name of the driver 8250_gsc.c suggests that it handles
only serial ports on the GSC bus, it does handle serial ports listed
in the parisc machine inventory as well, e.g. the serial ports in a
C8000 PCI-only workstation.

Change the dependency to CONFIG_PARISC, so that the driver gets included
in the kernel even if CONFIG_GSC isn't set.

Reported-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-10 17:57:56 +01:00
Pali Rohár
558a9fcb6c serial: 8250: Fix restoring termios speed after suspend
[ Upstream commit 379a33786d489ab81885ff0b3935cfeb36137fea ]

Since commit edc6afc54968 ("tty: switch to ktermios and new framework")
termios speed is no longer stored only in c_cflag member but also in new
additional c_ispeed and c_ospeed members. If BOTHER flag is set in c_cflag
then termios speed is stored only in these new members.

Since commit 027b57170bf8 ("serial: core: Fix initializing and restoring
termios speed") termios speed is available also in struct console.

So properly restore also c_ispeed and c_ospeed members after suspend to fix
restoring termios speed which is not represented by Bnnn constant.

Fixes: 4516d50aabed ("serial: 8250: Use canary to restart console after suspend")
Signed-off-by: Pali Rohár <pali@kernel.org>
Link: https://lore.kernel.org/r/20220924104324.4035-1-pali@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 13:22:41 +02:00
Sherry Sun
29b897ac7b tty: serial: fsl_lpuart: disable dma rx/tx use flags in lpuart_dma_shutdown
[ Upstream commit 316ae95c175a7d770d1bfe4c011192712f57aa4a ]

lpuart_dma_shutdown tears down lpuart dma, but lpuart_flush_buffer can
still occur which in turn tries to access dma apis if lpuart_dma_tx_use
flag is true. At this point since dma is torn down, these dma apis can
abort. Set lpuart_dma_tx_use and the corresponding rx flag
lpuart_dma_rx_use to false in lpuart_dma_shutdown so that dmas are not
accessed after they are relinquished.

Otherwise, when try to kill btattach, kernel may panic. This patch may
fix this issue.
root@imx8ulpevk:~# btattach -B /dev/ttyLP2 -S 115200
^C[   90.182296] Internal error: synchronous external abort: 96000210 [#1] PREEMPT SMP
[   90.189806] Modules linked in: moal(O) mlan(O)
[   90.194258] CPU: 0 PID: 503 Comm: btattach Tainted: G           O      5.15.32-06136-g34eecdf2f9e4 #37
[   90.203554] Hardware name: NXP i.MX8ULP 9X9 EVK (DT)
[   90.208513] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   90.215470] pc : fsl_edma3_disable_request+0x8/0x60
[   90.220358] lr : fsl_edma3_terminate_all+0x34/0x20c
[   90.225237] sp : ffff800013f0bac0
[   90.228548] x29: ffff800013f0bac0 x28: 0000000000000001 x27: ffff000008404800
[   90.235681] x26: ffff000008404960 x25: ffff000008404a08 x24: ffff000008404a00
[   90.242813] x23: ffff000008404a60 x22: 0000000000000002 x21: 0000000000000000
[   90.249946] x20: ffff800013f0baf8 x19: ffff00000559c800 x18: 0000000000000000
[   90.257078] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
[   90.264211] x14: 0000000000000003 x13: 0000000000000000 x12: 0000000000000040
[   90.271344] x11: ffff00000600c248 x10: ffff800013f0bb10 x9 : ffff000057bcb090
[   90.278477] x8 : fffffc0000241a08 x7 : ffff00000534ee00 x6 : ffff000008404804
[   90.285609] x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff0000055b3480
[   90.292742] x2 : ffff8000135c0000 x1 : ffff00000534ee00 x0 : ffff00000559c800
[   90.299876] Call trace:
[   90.302321]  fsl_edma3_disable_request+0x8/0x60
[   90.306851]  lpuart_flush_buffer+0x40/0x160
[   90.311037]  uart_flush_buffer+0x88/0x120
[   90.315050]  tty_driver_flush_buffer+0x20/0x30
[   90.319496]  hci_uart_flush+0x44/0x90
[   90.323162]  +0x34/0x12c
[   90.327253]  tty_ldisc_close+0x38/0x70
[   90.331005]  tty_ldisc_release+0xa8/0x190
[   90.335018]  tty_release_struct+0x24/0x8c
[   90.339022]  tty_release+0x3ec/0x4c0
[   90.342593]  __fput+0x70/0x234
[   90.345652]  ____fput+0x14/0x20
[   90.348790]  task_work_run+0x84/0x17c
[   90.352455]  do_exit+0x310/0x96c
[   90.355688]  do_group_exit+0x3c/0xa0
[   90.359259]  __arm64_sys_exit_group+0x1c/0x20
[   90.363609]  invoke_syscall+0x48/0x114
[   90.367362]  el0_svc_common.constprop.0+0xd4/0xfc
[   90.372068]  do_el0_svc+0x2c/0x94
[   90.375379]  el0_svc+0x28/0x80
[   90.378438]  el0t_64_sync_handler+0xa8/0x130
[   90.382711]  el0t_64_sync+0x1a0/0x1a4
[   90.386376] Code: 17ffffda d503201f d503233f f9409802 (b9400041)
[   90.392467] ---[ end trace 2f60524b4a43f1f6 ]---
[   90.397073] note: btattach[503] exited with preempt_count 1
[   90.402636] Fixing recursive fault but reboot is needed!

Fixes: 6250cc30c4c4 ("tty: serial: fsl_lpuart: Use scatter/gather DMA for Tx")
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Thara Gopinath <tgopinath@microsoft.com>
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20220920111703.1532-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 13:22:40 +02:00
Dan Carpenter
744c2d33a8 drivers: serial: jsm: fix some leaks in probe
[ Upstream commit 1d5859ef229e381f4db38dce8ed58e4bf862006b ]

This error path needs to unwind instead of just returning directly.

Fixes: 03a8482c17dd ("drivers: serial: jsm: Enable support for Digi Classic adapters")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/YyxFh1+lOeZ9WfKO@kili
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 13:22:40 +02:00
Shubhrajyoti Datta
80a955dabb tty: xilinx_uartps: Fix the ignore_status
[ Upstream commit b8a6c3b3d4654fba19881cc77da61eac29f57cae ]

Currently the ignore_status is not considered in the isr.
Add a check to add the ignore_status.

Fixes: 61ec9016988f ("tty/serial: add support for Xilinx PS UART")
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Link: https://lore.kernel.org/r/20220729114748.18332-5-shubhrajyoti.datta@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 13:22:36 +02:00
Ilpo Järvinen
9eb710d184 serial: tegra-tcu: Use uart_xmit_advance(), fixes icount.tx accounting
commit 1d10cd4da593bc0196a239dcc54dac24b6b0a74e upstream.

Tx'ing does not correctly account Tx'ed characters into icount.tx.
Using uart_xmit_advance() fixes the problem.

Fixes: 2d908b38d409 ("serial: Add Tegra Combined UART driver")
Cc: <stable@vger.kernel.org> # serial: Create uart_xmit_advance()
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220901143934.8850-4-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-28 11:04:08 +02:00
Ilpo Järvinen
6cc0434f9d serial: tegra: Use uart_xmit_advance(), fixes icount.tx accounting
commit 754f68044c7dd6c52534ba3e0f664830285c4b15 upstream.

DMA complete & stop paths did not correctly account Tx'ed characters
into icount.tx. Using uart_xmit_advance() fixes the problem.

Fixes: e9ea096dd225 ("serial: tegra: add serial driver")
Cc: <stable@vger.kernel.org> # serial: Create uart_xmit_advance()
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220901143934.8850-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-28 11:04:08 +02:00
Sergiu Moga
da8ac08694 tty: serial: atmel: Preserve previous USART mode if RS485 disabled
[ Upstream commit 692a8ebcfc24f4a5bea0eb2967e450f584193da6 ]

Whenever the atmel_rs485_config() driver method would be called,
the USART mode is reset to normal mode before even checking if
RS485 flag is set, thus resulting in losing the previous USART
mode in the case where the checking fails.

Some tools, such as `linux-serial-test`, lead to the driver calling
this method when doing the setup of the serial port: after setting the
port mode (Hardware Flow Control, Normal Mode, RS485 Mode, etc.),
`linux-serial-test` tries to enable/disable RS485 depending on
the commandline arguments that were passed.

Example of how this issue could reveal itself:
When doing a serial communication with Hardware Flow Control through
`linux-serial-test`, the tool would lead to the driver roughly doing
the following:
- set the corresponding bit to 1 (ATMEL_US_USMODE_HWHS bit in the
ATMEL_US_MR register) through the atmel_set_termios() to enable
Hardware Flow Control
- disable RS485 through the atmel_config_rs485() method
Thus, when the latter is called, the mode will be reset and the
previously set bit is unset, leaving USART in normal mode instead of
the expected Hardware Flow Control mode.

This fix ensures that this reset is only done if the checking for
RS485 succeeds and that the previous mode is preserved otherwise.

Fixes: e8faff7330a35 ("ARM: 6092/1: atmel_serial: support for RS485 communications")
Cc: stable <stable@kernel.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Sergiu Moga <sergiu.moga@microchip.com>
Link: https://lore.kernel.org/r/20220824142902.502596-1-sergiu.moga@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-28 11:04:02 +02:00
Lino Sanfilippo
e56a402819 serial: atmel: remove redundant assignment in rs485_config
[ Upstream commit 60efd0513916f195dd85bfbf21653f74f9ab019c ]

In uart_set_rs485_config() the serial core already assigns the passed
serial_rs485 struct to the uart port.

So remove the assignment from the drivers rs485_config() function to avoid
redundancy.

Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-10-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 692a8ebcfc24 ("tty: serial: atmel: Preserve previous USART mode if RS485 disabled")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-28 11:04:02 +02:00
Codrin.Ciubotariu@microchip.com
85a64208b3 tty/serial: atmel: RS485 & ISO7816: wait for TXRDY before sending data
[ Upstream commit 477b8383100023ea0769979cff67e9be3a720397 ]

At this moment, TXEMPTY is checked before sending data on RS485 and ISO7816
modes. However, TXEMPTY is risen when FIFO (if used) or the Transmit Shift
Register are empty, even though TXRDY might be up and controller is able to
receive data. Since the controller sends data only when TXEMPTY is ready,
on RS485, when DMA is not used, the RTS pin is driven low after each byte.
With this patch, the characters will be transmitted when TXRDY is up and
so, RTS pin will remain high between bytes.
The performance improvement on RS485 is about 8% with a baudrate of 300.

Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Link: https://lore.kernel.org/r/20200107111656.26308-1-codrin.ciubotariu@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 692a8ebcfc24 ("tty: serial: atmel: Preserve previous USART mode if RS485 disabled")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-28 11:04:02 +02:00
Sherry Sun
a6b7e8d975 tty: serial: lpuart: disable flow control while waiting for the transmit engine to complete
commit d5a2e0834364377a5d5a2fff1890a0b3f0bafd1f upstream.

When the user initializes the uart port, and waits for the transmit
engine to complete in lpuart32_set_termios(), if the UART TX fifo has
dirty data and the UARTMODIR enable the flow control, the TX fifo may
never be empty. So here we should disable the flow control first to make
sure the transmit engin can complete.

Fixes: 380c966c093e ("tty: serial: fsl_lpuart: add 32-bit register interface support")
Cc: stable <stable@kernel.org>
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20220821101527.10066-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-15 12:04:51 +02:00
Helge Deller
1cf1930369 vt: Clear selection before changing the font
commit 566f9c9f89337792070b5a6062dff448b3e7977f upstream.

When changing the console font with ioctl(KDFONTOP) the new font size
can be bigger than the previous font. A previous selection may thus now
be outside of the new screen size and thus trigger out-of-bounds
accesses to graphics memory if the selection is removed in
vc_do_resize().

Prevent such out-of-memory accesses by dropping the selection before the
various con_font_set() console handlers are called.

Reported-by: syzbot+14b0e8f3fd1612e35350@syzkaller.appspotmail.com
Cc: stable <stable@kernel.org>
Tested-by: Khalid Masum <khalid.masum.92@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Link: https://lore.kernel.org/r/YuV9apZGNmGfjcor@p100
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-15 12:04:51 +02:00
Shenwei Wang
a65a2a33c6 serial: fsl_lpuart: RS485 RTS polariy is inverse
commit 846651eca073e2e02e37490a4a52752415d84781 upstream.

The setting of RS485 RTS polarity is inverse in the current driver.

When the property of 'rs485-rts-active-low' is enabled in the dts node,
the RTS signal should be LOW during sending. Otherwise, if there is no
such a property, the RTS should be HIGH during sending.

Fixes: 03895cf41d18 ("tty: serial: fsl_lpuart: Add support for RS-485")
Cc: stable <stable@kernel.org>
Signed-off-by: Nicolas Diaz <nicolas.diaz@nxp.com>
Signed-off-by: Shenwei Wang <shenwei.wang@nxp.com>
Link: https://lore.kernel.org/r/20220805144529.604856-1-shenwei.wang@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-15 12:04:50 +02:00
Liang He
ca3fc1c38e tty: serial: Fix refcount leak bug in ucc_uart.c
[ Upstream commit d24d7bb2cd947676f9b71fb944d045e09b8b282f ]

In soc_info(), of_find_node_by_type() will return a node pointer
with refcount incremented. We should use of_node_put() when it is
not used anymore.

Acked-by: Timur Tabi <timur@kernel.org>
Signed-off-by: Liang He <windhl@126.com>
Link: https://lore.kernel.org/r/20220618060850.4058525-1-windhl@126.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-25 11:18:36 +02:00
Daniel Starke
44913ccfa1 tty: n_gsm: fix missing corner cases in gsmld_poll()
[ Upstream commit 7e5b4322cde067e1d0f1bf8f490e93f664a7c843 ]

gsmld_poll() currently fails to handle the following corner cases correctly:
- remote party closed the associated tty

Add the missing checks and map those to EPOLLHUP.
Reorder the checks to group them by their reaction.

Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220707113223.3685-4-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-25 11:18:03 +02:00
Daniel Starke
ae9bfcbfd7 tty: n_gsm: fix DM command
[ Upstream commit 18a948c7d90995d127785e308fa7b701df4c499f ]

n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. Chapter 5.3.3 defines the DM response. There exists
no DM command. However, the current implementation incorrectly sends DM as
command in case of unexpected UIH frames in gsm_queue().
Correct this behavior by always sending DM as response.

Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220707113223.3685-2-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-25 11:18:03 +02:00
Daniel Starke
b625b74549 tty: n_gsm: fix wrong T1 retry count handling
[ Upstream commit f30e10caa80aa1f35508bc17fc302dbbde9a833c ]

n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. Chapter 5.7.3 states that the valid range for the
maximum number of retransmissions (N2) is from 0 to 255 (both including).
gsm_dlci_t1() handles this number incorrectly by performing N2 - 1
retransmission attempts. Setting N2 to zero results in more than 255
retransmission attempts.
Fix gsm_dlci_t1() to comply with 3GPP 27.010.

Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220707113223.3685-1-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-25 11:18:03 +02:00
Daniel Starke
fbf9795646 tty: n_gsm: fix race condition in gsmld_write()
[ Upstream commit 32dd59f96924f45e33bc79854f7a00679c0fa28e ]

The function may be used by the user directly and also by the n_gsm
internal functions. They can lead into a race condition which results in
interleaved frames if both are writing at the same time. The receiving side
is not able to decode those interleaved frames correctly.

Add a lock around the low side tty write to avoid race conditions and frame
interleaving between user originated writes and n_gsm writes.

Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220701061652.39604-9-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-25 11:18:02 +02:00
Daniel Starke
597bec4a4c tty: n_gsm: fix packet re-transmission without open control channel
[ Upstream commit 4fae831b3a71fc5a44cc5c7d0b8c1267ee7659f5 ]

In the current implementation control packets are re-transmitted even if
the control channel closed down during T2. This is wrong.
Check whether the control channel is open before re-transmitting any
packets. Note that control channel open/close is handled by T1 and not T2
and remains unaffected by this.

Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220701061652.39604-7-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-25 11:18:02 +02:00
Daniel Starke
ba10f6c2f0 tty: n_gsm: fix non flow control frames during mux flow off
[ Upstream commit bec0224816d19abe4fe503586d16d51890540615 ]

n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. Chapter 5.4.6.3.6 states that FCoff stops the
transmission on all channels except the control channel. This is already
implemented in gsm_data_kick(). However, chapter 5.4.8.1 explains that this
shall result in the same behavior as software flow control on the ldisc in
advanced option mode. That means only flow control frames shall be sent
during flow off. The current implementation does not consider this case.

Change gsm_data_kick() to send only flow control frames if constipated to
abide the standard. gsm_read_ea_val() and gsm_is_flow_ctrl_msg() are
introduced as helper functions for this.
It is planned to use gsm_read_ea_val() in later code cleanups for other
functions, too.

Fixes: c01af4fec2c8 ("n_gsm : Flow control handling in Mux driver")
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220701061652.39604-5-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-25 11:18:02 +02:00
Ilpo Järvinen
34734e4c52 serial: 8250_dw: Store LSR into lsr_saved_flags in dw8250_tx_wait_empty()
[ Upstream commit af14f3007e2dca0d112f10f6717ba43093f74e81 ]

Make sure LSR flags are preserved in dw8250_tx_wait_empty(). This
function is called from a low-level out function and therefore cannot
call serial_lsr_in() as it would lead to infinite recursion.

It is borderline if the flags need to be saved here at all since this
code relates to writing LCR register which usually implies no important
characters should be arriving.

Fixes: 914eaf935ec7 ("serial: 8250_dw: Allow TX FIFO to drain before writing to UART_LCR")
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220608095431.18376-7-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-25 11:18:01 +02:00
Narendra Hadke
ecd489683a serial: mvebu-uart: uart2 error bits clearing
commit a7209541239e5dd44d981289e5f9059222d40fd1 upstream.

For mvebu uart2, error bits are not cleared on buffer read.
This causes interrupt loop and system hang.

Cc: stable@vger.kernel.org
Reviewed-by: Yi Guo <yi.guo@cavium.com>
Reviewed-by: Nadav Haklai <nadavh@marvell.com>
Signed-off-by: Narendra Hadke <nhadke@marvell.com>
Signed-off-by: Pali Rohár <pali@kernel.org>
Link: https://lore.kernel.org/r/20220726091221.12358-1-pali@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-25 11:17:24 +02:00
Tetsuo Handa
cc9e874dac tty: vt: initialize unicode screen buffer
commit af77c56aa35325daa2bc2bed5c2ebf169be61b86 upstream.

syzbot reports kernel infoleak at vcs_read() [1], for buffer can be read
immediately after resize operation. Initialize buffer using kzalloc().

  ----------
  #include <fcntl.h>
  #include <unistd.h>
  #include <sys/ioctl.h>
  #include <linux/fb.h>

  int main(int argc, char *argv[])
  {
    struct fb_var_screeninfo var = { };
    const int fb_fd = open("/dev/fb0", 3);
    ioctl(fb_fd, FBIOGET_VSCREENINFO, &var);
    var.yres = 0x21;
    ioctl(fb_fd, FBIOPUT_VSCREENINFO, &var);
    return read(open("/dev/vcsu", O_RDONLY), &var, sizeof(var)) == -1;
  }
  ----------

Link: https://syzkaller.appspot.com/bug?extid=31a641689d43387f05d3 [1]
Cc: stable <stable@vger.kernel.org>
Reported-by: syzbot <syzbot+31a641689d43387f05d3@syzkaller.appspotmail.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Link: https://lore.kernel.org/r/4ef053cf-e796-fb5e-58b7-3ae58242a4ad@I-love.SAKURA.ne.jp
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-25 11:17:21 +02:00
Jiri Slaby
f7785092cb tty: use new tty_insert_flip_string_and_push_buffer() in pty_write()
commit a501ab75e7624d133a5a3c7ec010687c8b961d23 upstream.

There is a race in pty_write(). pty_write() can be called in parallel
with e.g. ioctl(TIOCSTI) or ioctl(TCXONC) which also inserts chars to
the buffer. Provided, tty_flip_buffer_push() in pty_write() is called
outside the lock, it can commit inconsistent tail. This can lead to out
of bounds writes and other issues. See the Link below.

To fix this, we have to introduce a new helper called
tty_insert_flip_string_and_push_buffer(). It does both
tty_insert_flip_string() and tty_flip_buffer_commit() under the port
lock. It also calls queue_work(), but outside the lock. See
71a174b39f10 (pty: do tty_flip_buffer_push without port->lock in
pty_write) for the reasons.

Keep the helper internal-only (in drivers' tty.h). It is not intended to
be used widely.

Link: https://seclists.org/oss-sec/2022/q2/155
Fixes: 71a174b39f10 (pty: do tty_flip_buffer_push without port->lock in pty_write)
Cc: 一只狗 <chennbnbnb@gmail.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Suggested-by: Hillf Danton <hdanton@sina.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220707082558.9250-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29 17:14:20 +02:00
Jiri Slaby
815d936e92 tty: extract tty_flip_buffer_commit() from tty_flip_buffer_push()
commit 716b10580283fda66f2b88140e3964f8a7f9da89 upstream.

We will need this new helper in the next patch.

Cc: Hillf Danton <hdanton@sina.com>
Cc: 一只狗 <chennbnbnb@gmail.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220707082558.9250-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29 17:14:19 +02:00
Jiri Slaby
2ea77b0b6d tty: drop tty_schedule_flip()
commit 5db96ef23bda6c2a61a51693c85b78b52d03f654 upstream.

Since commit a9c3f68f3cd8d (tty: Fix low_latency BUG) in 2014,
tty_flip_buffer_push() is only a wrapper to tty_schedule_flip(). All
users were converted in the previous patches, so remove
tty_schedule_flip() completely while inlining its body into
tty_flip_buffer_push().

One less exported function.

Reviewed-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20211122111648.30379-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29 17:14:19 +02:00
Jiri Slaby
aa60c0cce8 tty: drivers/tty/, stop using tty_schedule_flip()
commit 5f6a85158ccacc3f09744b3aafe8b11ab3b6c6f6 upstream.

Since commit a9c3f68f3cd8d (tty: Fix low_latency BUG) in 2014,
tty_flip_buffer_push() is only a wrapper to tty_schedule_flip(). We are
going to remove the latter (as it is used less), so call the former in
drivers/tty/.

Cc: Vladimir Zapolskiy <vz@mleia.com>
Reviewed-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20211122111648.30379-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29 17:14:19 +02:00
Pali Rohár
c68f6e2e4f serial: mvebu-uart: correctly report configured baudrate value
commit 4f532c1e25319e42996ec18a1f473fd50c8e575d upstream.

Functions tty_termios_encode_baud_rate() and uart_update_timeout() should
be called with the baudrate value which was set to hardware. Linux then
report exact values via ioctl(TCGETS2) to userspace.

Change mvebu_uart_baud_rate_set() function to return baudrate value which
was set to hardware and propagate this value to above mentioned functions.

With this change userspace would see precise value in termios c_ospeed
field.

Fixes: 68a0db1d7da2 ("serial: mvebu-uart: add function to change baudrate")
Cc: stable <stable@kernel.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Pali Rohár <pali@kernel.org>
Link: https://lore.kernel.org/r/20220628100922.10717-1-pali@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29 17:14:09 +02:00
Ilpo Järvinen
579c8a2e63 serial: pl011: UPSTAT_AUTORTS requires .throttle/unthrottle
commit 211565b100993c90b53bf40851eacaefc830cfe0 upstream.

The driver must provide throttle and unthrottle in uart_ops when it
sets UPSTAT_AUTORTS. Add them using existing stop_rx &
enable_interrupts functions.

Fixes: 2a76fa283098 (serial: pl011: Adopt generic flag to store auto RTS status)
Cc: stable <stable@kernel.org>
Cc: Lukas Wunner <lukas@wunner.de>
Reported-by: Nuno Gonçalves <nunojpg@gmail.com>
Tested-by: Nuno Gonçalves <nunojpg@gmail.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220614075637.8558-1-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-21 20:59:28 +02:00
Ilpo Järvinen
0c8649a497 serial: stm32: Clear prev values before setting RTS delays
commit 5c5f44e36217de5ead789ff25da71c31c2331c96 upstream.

The code lacks clearing of previous DEAT/DEDT values. Thus, changing
values on the fly results in garbage delays tending towards the maximum
value as more and more bits are ORed together. (Leaving RS485 mode
would have cleared the old values though).

Fixes: 1bcda09d2910 ("serial: stm32: add support for RS485 hardware control mode")
Cc: stable <stable@kernel.org>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220627150753.34510-1-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-21 20:59:28 +02:00
Yi Yang
f4c7f5028b serial: 8250: fix return error code in serial8250_request_std_resource()
commit 6e690d54cfa802f939cefbd2fa2c91bd0b8bd1b6 upstream.

If port->mapbase = NULL in serial8250_request_std_resource() , it need
return a error code instead of 0. If uart_set_info() fail to request new
regions by serial8250_request_std_resource() but the return value of
serial8250_request_std_resource() is 0, The system incorrectly considers
that the resource application is successful and does not attempt to
restore the old setting. A null pointer reference is triggered when the
port resource is later invoked.

Signed-off-by: Yi Yang <yiyang13@huawei.com>
Cc: stable <stable@kernel.org>
Link: https://lore.kernel.org/r/20220628083515.64138-1-yiyang13@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-21 20:59:28 +02:00
Chanho Park
07379bd79d tty: serial: samsung_tty: set dma burst_size to 1
commit f7e35e4bf1e8dc2c8cbd5e0955dc1bd58558dae0 upstream.

The src_maxburst and dst_maxburst have been changed to 1 but the settings
of the UCON register aren't changed yet. They should be changed as well
according to the dmaengine slave config.

Fixes: aa2f80e752c7 ("serial: samsung: fix maxburst parameter for DMA transactions")
Cc: stable <stable@kernel.org>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Link: https://lore.kernel.org/r/20220627065113.139520-1-chanho61.park@samsung.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-21 20:59:28 +02:00
Jiri Slaby
c87e851b23 vt: drop old FONT ioctls
commit ff2047fb755d4415ec3c70ac799889371151796d upstream.

Drop support for these ioctls:
* PIO_FONT, PIO_FONTX
* GIO_FONT, GIO_FONTX
* PIO_FONTRESET

As was demonstrated by commit 90bfdeef83f1 (tty: make FONTX ioctl use
the tty pointer they were actually passed), these ioctls are not used
from userspace, as:
1) they used to be broken (set up font on current console, not the open
   one) and racy (before the commit above)
2) KDFONTOP ioctl is used for years instead

Note that PIO_FONTRESET is defunct on most systems as VGA_CONSOLE is set
on them for ages. That turns on BROKEN_GRAPHICS_PROGRAMS which makes
PIO_FONTRESET just return an error.

We are removing KD_FONT_FLAG_OLD here as it was used only by these
removed ioctls. kd.h header exists both in kernel and uapi headers, so
we can remove the kernel one completely. Everyone includeing kd.h will
now automatically get the uapi one.

There are now unused definitions of the ioctl numbers and "struct
consolefontdesc" in kd.h, but as it is a uapi header, I am not touching
these.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210105120239.28031-8-jslaby@suse.cz
Cc: guodaxing <guodaxing@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-29 08:58:44 +02:00
Ilpo Järvinen
64d2df6480 serial: 8250: Store to lsr_save_flags after lsr read
commit be03b0651ffd8bab69dfd574c6818b446c0753ce upstream.

Not all LSR register flags are preserved across reads. Therefore, LSR
readers must store the non-preserved bits into lsr_save_flags.

This fix was initially mixed into feature commit f6f586102add ("serial:
8250: Handle UART without interrupt on TEMT using em485"). However,
that feature change had a flaw and it was reverted to make room for
simpler approach providing the same feature. The embedded fix got
reverted with the feature change.

Re-add the lsr_save_flags fix and properly mark it's a fix.

Link: https://lore.kernel.org/all/1d6c31d-d194-9e6a-ddf9-5f29af829f3@linux.intel.com/T/#m1737eef986bd20cf19593e344cebd7b0244945fc
Fixes: e490c9144cfa ("tty: Add software emulated RS485 support for 8250")
Cc: stable <stable@kernel.org>
Acked-by: Uwe Kleine-König <u.kleine-koenig@penugtronix.de>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/f4d774be-1437-a550-8334-19d8722ab98c@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-22 14:11:23 +02:00
Vincent Whitchurch
f7183c76d5 tty: goldfish: Fix free_irq() on remove
[ Upstream commit 499e13aac6c762e1e828172b0f0f5275651d6512 ]

Pass the correct dev_id to free_irq() to fix this splat when the driver
is unbound:

 WARNING: CPU: 0 PID: 30 at kernel/irq/manage.c:1895 free_irq
 Trying to free already-free IRQ 65
 Call Trace:
  warn_slowpath_fmt
  free_irq
  goldfish_tty_remove
  platform_remove
  device_remove
  device_release_driver_internal
  device_driver_detach
  unbind_store
  drv_attr_store
  ...

Fixes: 465893e18878e119 ("tty: goldfish: support platform_device with id -1")
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Link: https://lore.kernel.org/r/20220609141704.1080024-1-vincent.whitchurch@axis.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-22 14:11:22 +02:00
John Ogness
19f4b51b83 serial: msm_serial: disable interrupts in __msm_console_write()
[ Upstream commit aabdbb1b7a5819e18c403334a31fb0cc2c06ad41 ]

__msm_console_write() assumes that interrupts are disabled, but
with threaded console printers it is possible that the write()
callback of the console is called with interrupts enabled.

Explicitly disable interrupts using local_irq_save() to preserve
the assumed context.

Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20220506213324.470461-1-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-14 18:12:00 +02:00
Duoming Zhou
09a5958a24 drivers: tty: serial: Fix deadlock in sa1100_set_termios()
[ Upstream commit 62b2caef400c1738b6d22f636c628d9f85cd4c4c ]

There is a deadlock in sa1100_set_termios(), which is shown
below:

   (Thread 1)              |      (Thread 2)
                           | sa1100_enable_ms()
sa1100_set_termios()       |  mod_timer()
 spin_lock_irqsave() //(1) |  (wait a time)
 ...                       | sa1100_timeout()
 del_timer_sync()          |  spin_lock_irqsave() //(2)
 (wait timer to stop)      |  ...

We hold sport->port.lock in position (1) of thread 1 and
use del_timer_sync() to wait timer to stop, but timer handler
also need sport->port.lock in position (2) of thread 2. As a result,
sa1100_set_termios() will block forever.

This patch moves del_timer_sync() before spin_lock_irqsave()
in order to prevent the deadlock.

Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Link: https://lore.kernel.org/r/20220417111626.7802-1-duoming@zju.edu.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-14 18:11:59 +02:00
Huang Guobin
8c014373f1 tty: Fix a possible resource leak in icom_probe
[ Upstream commit ee157a79e7c82b01ae4c25de0ac75899801f322c ]

When pci_read_config_dword failed, call pci_release_regions() and
pci_disable_device() to recycle the resource previously allocated.

Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Huang Guobin <huangguobin4@huawei.com>
Link: https://lore.kernel.org/r/20220331091005.3290753-1-huangguobin4@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-14 18:11:59 +02:00
Zheyu Ma
f6e07eb7eb tty: synclink_gt: Fix null-pointer-dereference in slgt_clean()
[ Upstream commit 689ca31c542687709ba21ec2195c1fbce34fd029 ]

When the driver fails at alloc_hdlcdev(), and then we remove the driver
module, we will get the following splat:

[   25.065966] general protection fault, probably for non-canonical address 0xdffffc0000000182: 0000 [#1] PREEMPT SMP KASAN PTI
[   25.066914] KASAN: null-ptr-deref in range [0x0000000000000c10-0x0000000000000c17]
[   25.069262] RIP: 0010:detach_hdlc_protocol+0x2a/0x3e0
[   25.077709] Call Trace:
[   25.077924]  <TASK>
[   25.078108]  unregister_hdlc_device+0x16/0x30
[   25.078481]  slgt_cleanup+0x157/0x9f0 [synclink_gt]

Fix this by checking whether the 'info->netdev' is a null pointer first.

Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Link: https://lore.kernel.org/r/20220410114814.3920474-1-zheyuma97@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-14 18:11:59 +02:00
Ilpo Järvinen
c3a16e7c86 serial: stm32-usart: Correct CSIZE, bits, and parity
[ Upstream commit 1deeda8d2877c18bc2b9eeee10dd6d2628852848 ]

Add CSIZE sanitization for unsupported CSIZE configurations. In
addition, if parity is asked for but CSx was unsupported, the sensible
result is CS8+parity which requires setting USART_CR1_M0 like with 9
bits.

Incorrect CSIZE results in miscalculation of the frame bits in
tty_get_char_size() or in its predecessor where the roughly the same
code is directly within uart_update_timeout().

Fixes: c8a9d043947b (serial: stm32: fix word length configuration)
Cc: Erwan Le Ray <erwan.leray@st.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220519081808.3776-9-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-14 18:11:54 +02:00
Ilpo Järvinen
29d963635e serial: st-asc: Sanitize CSIZE and correct PARENB for CS7
[ Upstream commit 52bb1cb7118564166b04d52387bd8403632f5190 ]

Only CS7 and CS8 seem supported but CSIZE is not sanitized from CS5 or
CS6 to CS8. In addition, ASC_CTL_MODE_7BIT_PAR suggests that CS7 has
to have parity, thus add PARENB.

Incorrect CSIZE results in miscalculation of the frame bits in
tty_get_char_size() or in its predecessor where the roughly the same
code is directly within uart_update_timeout().

Fixes: c4b058560762 (serial:st-asc: Add ST ASC driver.)
Cc: Srinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220519081808.3776-8-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-14 18:11:53 +02:00
Ilpo Järvinen
5c01c19f64 serial: sifive: Sanitize CSIZE and c_iflag
[ Upstream commit c069d2756c01ed36121fae6a42c14fdf1325c71d ]

Only CS8 is supported but CSIZE was not sanitized to CS8.

Set CSIZE correctly so that userspace knows the effective value.
Incorrect CSIZE also results in miscalculation of the frame bits in
tty_get_char_size() or in its predecessor where the roughly the same
code is directly within uart_update_timeout().

Similarly, INPCK, PARMRK, and BRKINT are reported textually unsupported
but were not cleared in termios c_iflag which is the machine-readable
format.

Fixes: 45c054d0815b (tty: serial: add driver for the SiFive UART)
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220519081808.3776-7-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-14 18:11:53 +02:00