linux-stable.git/drivers/tty, branch v4.9.334

serial: 8250: Flush DMA Rx on RLSI

2022-11-25T16:35:42+00:00

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: 
Signed-off-by: Ilpo Järvinen 
Reviewed-by: Andy Shevchenko 
Link: https://lore.kernel.org/r/20221108121952.5497-5-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman

serial: 8250_lpss: Configure DMA also w/o DMA filter

2022-11-25T16:35:42+00:00

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 
Signed-off-by: Ilpo Järvinen 
Reviewed-by: Andy Shevchenko 
Link: https://lore.kernel.org/r/20221108121952.5497-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman

serial: 8250: Fall back to non-DMA Rx if IIR_RDI occurs

2022-11-25T16:35:42+00:00

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: 
Co-developed-by: Srikanth Thokala 
Signed-off-by: Srikanth Thokala 
Co-developed-by: Aman Kumar 
Signed-off-by: Aman Kumar 
Signed-off-by: Ilpo Järvinen 
Reviewed-by: Andy Shevchenko 
Link: https://lore.kernel.org/r/20221108121952.5497-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman

tty: n_gsm: fix sleep-in-atomic-context bug in gsm_control_send

2022-11-25T16:35:39+00:00

[ 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 
Link: https://lore.kernel.org/r/20221002040709.27849-1-duoming@zju.edu.cn
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

serial: 8250: omap: Flush PM QOS work on remove

2022-11-25T16:35:39+00:00

[ 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 
Link: https://lore.kernel.org/r/20221028110044.54719-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

serial: 8250_omap: remove wait loop from Errata i202 workaround

2022-11-25T16:35:38+00:00

[ 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 
Signed-off-by: Matthias Schiffer 
Link: https://lore.kernel.org/r/20221013112339.2540767-1-matthias.schiffer@ew.tq-group.com
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

parisc: Make 8250_gsc driver dependend on CONFIG_PARISC

2022-11-10T14:46:07+00:00

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 
Cc: 
Signed-off-by: Helge Deller 
Signed-off-by: Greg Kroah-Hartman

serial: 8250: Fix restoring termios speed after suspend

2022-10-26T11:15:43+00:00

[ 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 
Link: https://lore.kernel.org/r/20220924104324.4035-1-pali@kernel.org
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

drivers: serial: jsm: fix some leaks in probe

2022-10-26T11:15:43+00:00

[ 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 
Link: https://lore.kernel.org/r/YyxFh1+lOeZ9WfKO@kili
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

tty: xilinx_uartps: Fix the ignore_status

2022-10-26T11:15:42+00:00

[ 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 
Link: https://lore.kernel.org/r/20220729114748.18332-5-shubhrajyoti.datta@xilinx.com
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin