Commit graph

8,906 commits

Author SHA1 Message Date
Hugo Villeneuve
dc5ead0e8f serial: sc16is7xx: fix invalid FIFO access with special register set
[ Upstream commit 7d3b793faa ]

When enabling access to the special register set, Receiver time-out and
RHR interrupts can happen. In this case, the IRQ handler will try to read
from the FIFO thru the RHR register at address 0x00, but address 0x00 is
mapped to DLL register, resulting in erroneous FIFO reading.

Call graph example:
    sc16is7xx_startup(): entry
    sc16is7xx_ms_proc(): entry
    sc16is7xx_set_termios(): entry
    sc16is7xx_set_baud(): DLH/DLL = $009C --> access special register set
    sc16is7xx_port_irq() entry            --> IIR is 0x0C
    sc16is7xx_handle_rx() entry
    sc16is7xx_fifo_read(): --> unable to access FIFO (RHR) because it is
                               mapped to DLL (LCR=LCR_CONF_MODE_A)
    sc16is7xx_set_baud(): exit --> Restore access to general register set

Fix the problem by claiming the efr_lock mutex when accessing the Special
register set.

Fixes: dfeae619d7 ("serial: sc16is7xx")
Cc: stable@vger.kernel.org
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20240723125302.1305372-3-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Resolve minor conflicts ]
Signed-off-by: Bin Lan <bin.lan.cn@windriver.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-09 10:31:40 +01:00
Johan Hovold
647cd4494c serial: qcom-geni: fix receiver enable
commit fa103d2599 upstream.

The receiver is supposed to be enabled in the startup() callback and not
in set_termios() which is called also during console setup.

This specifically avoids accepting input before the port has been opened
(and interrupts enabled), something which can also break the GENI
firmware (cancel fails and after abort, the "stale" counter handling
appears to be broken so that later input is not processed until twelve
chars have been received).

There also does not appear to be any need to keep the receiver disabled
while updating the port settings.

Since commit 6f3c3cafb1 ("serial: qcom-geni: disable interrupts during
console writes") the calls to manipulate the secondary interrupts, which
were done without holding the port lock, can also lead to the receiver
being left disabled when set_termios() races with the console code (e.g.
when init opens the tty during boot). This can manifest itself as a
serial getty not accepting input.

The calls to stop and start rx in set_termios() can similarly race with
DMA completion and, for example, cause the DMA buffer to be unmapped
twice or the mapping to be leaked.

Fix this by only enabling the receiver during startup and while holding
the port lock to avoid racing with the console code.

Fixes: 6f3c3cafb1 ("serial: qcom-geni: disable interrupts during console writes")
Fixes: 2aaa43c707 ("tty: serial: qcom-geni-serial: add support for serial engine DMA")
Fixes: c4f528795d ("tty: serial: msm_geni_serial: Add serial driver support for GENI based QUP")
Cc: stable@vger.kernel.org      # 6.3
Cc: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20241009145110.16847-6-johan+linaro@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-10-22 15:46:35 +02:00
Johan Hovold
61c8f746ed serial: qcom-geni: fix dma rx cancellation
commit 23ee4a2566 upstream.

Make sure to wait for the DMA transfer to complete when cancelling the
rx command on stop_rx(). This specifically prevents the DMA completion
interrupt from firing after rx has been restarted, something which can
lead to an IOMMU fault and hosed rx when the interrupt handler unmaps
the DMA buffer for the new command:

	qcom_geni_serial 988000.serial: serial engine reports 0 RX bytes in!
	arm-smmu 15000000.iommu: FSR    = 00000402 [Format=2 TF], SID=0x563
	arm-smmu 15000000.iommu: FSYNR0 = 00210013 [S1CBNDX=33 WNR PLVL=3]
	Bluetooth: hci0: command 0xfc00 tx timeout
	Bluetooth: hci0: Reading QCA version information failed (-110)

Also add the missing state machine reset which is needed in case
cancellation fails.

Fixes: 2aaa43c707 ("tty: serial: qcom-geni-serial: add support for serial engine DMA")
Cc: stable@vger.kernel.org      # 6.3
Cc: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/r/20241009145110.16847-5-johan+linaro@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-10-22 15:46:35 +02:00
Johan Hovold
7176aee5a1 serial: qcom-geni: revert broken hibernation support
commit 19df76662a upstream.

This reverts commit 35781d8356.

Hibernation is not supported on Qualcomm platforms with mainline
kernels yet a broken vendor implementation for the GENI serial driver
made it upstream.

This is effectively dead code that cannot be tested and should just be
removed, but if these paths were ever hit for an open non-console port
they would crash the machine as the driver would fail to enable clocks
during restore() (i.e. all ports would have to be closed by drivers and
user space before hibernating the system to avoid this as a comment in
the code hinted at).

The broken implementation also added a random call to enable the
receiver in the port setup code where it does not belong and which
enables the receiver prematurely for console ports.

Fixes: 35781d8356 ("tty: serial: qcom-geni-serial: Add support for Hibernation feature")
Cc: stable@vger.kernel.org	# 6.2
Cc: Aniket Randive <quic_arandive@quicinc.com>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/r/20241009145110.16847-3-johan+linaro@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-10-22 15:46:35 +02:00
Johan Hovold
90e3f819e6 serial: qcom-geni: fix polled console initialisation
commit 4bef7c6f29 upstream.

The polled console (KGDB/KDB) implementation must not call port setup
unconditionally as the port may already be in use by the console or a
getty.

Only make sure that the receiver is enabled, but do not enable any
device interrupts.

Fixes: d8851a96ba ("tty: serial: qcom-geni-serial: Add a poll_init() function")
Cc: stable@vger.kernel.org	# 6.4
Cc: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20241009145110.16847-2-johan+linaro@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-10-22 15:46:35 +02:00
Longlong Xia
c29f192e0d tty: n_gsm: Fix use-after-free in gsm_cleanup_mux
commit 9462f4ca56 upstream.

BUG: KASAN: slab-use-after-free in gsm_cleanup_mux+0x77b/0x7b0
drivers/tty/n_gsm.c:3160 [n_gsm]
Read of size 8 at addr ffff88815fe99c00 by task poc/3379
CPU: 0 UID: 0 PID: 3379 Comm: poc Not tainted 6.11.0+ #56
Hardware name: VMware, Inc. VMware Virtual Platform/440BX
Desktop Reference Platform, BIOS 6.00 11/12/2020
Call Trace:
 <TASK>
 gsm_cleanup_mux+0x77b/0x7b0 drivers/tty/n_gsm.c:3160 [n_gsm]
 __pfx_gsm_cleanup_mux+0x10/0x10 drivers/tty/n_gsm.c:3124 [n_gsm]
 __pfx_sched_clock_cpu+0x10/0x10 kernel/sched/clock.c:389
 update_load_avg+0x1c1/0x27b0 kernel/sched/fair.c:4500
 __pfx_min_vruntime_cb_rotate+0x10/0x10 kernel/sched/fair.c:846
 __rb_insert_augmented+0x492/0xbf0 lib/rbtree.c:161
 gsmld_ioctl+0x395/0x1450 drivers/tty/n_gsm.c:3408 [n_gsm]
 _raw_spin_lock_irqsave+0x92/0xf0 arch/x86/include/asm/atomic.h:107
 __pfx_gsmld_ioctl+0x10/0x10 drivers/tty/n_gsm.c:3822 [n_gsm]
 ktime_get+0x5e/0x140 kernel/time/timekeeping.c:195
 ldsem_down_read+0x94/0x4e0 arch/x86/include/asm/atomic64_64.h:79
 __pfx_ldsem_down_read+0x10/0x10 drivers/tty/tty_ldsem.c:338
 __pfx_do_vfs_ioctl+0x10/0x10 fs/ioctl.c:805
 tty_ioctl+0x643/0x1100 drivers/tty/tty_io.c:2818

Allocated by task 65:
 gsm_data_alloc.constprop.0+0x27/0x190 drivers/tty/n_gsm.c:926 [n_gsm]
 gsm_send+0x2c/0x580 drivers/tty/n_gsm.c:819 [n_gsm]
 gsm1_receive+0x547/0xad0 drivers/tty/n_gsm.c:3038 [n_gsm]
 gsmld_receive_buf+0x176/0x280 drivers/tty/n_gsm.c:3609 [n_gsm]
 tty_ldisc_receive_buf+0x101/0x1e0 drivers/tty/tty_buffer.c:391
 tty_port_default_receive_buf+0x61/0xa0 drivers/tty/tty_port.c:39
 flush_to_ldisc+0x1b0/0x750 drivers/tty/tty_buffer.c:445
 process_scheduled_works+0x2b0/0x10d0 kernel/workqueue.c:3229
 worker_thread+0x3dc/0x950 kernel/workqueue.c:3391
 kthread+0x2a3/0x370 kernel/kthread.c:389
 ret_from_fork+0x2d/0x70 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:257

Freed by task 3367:
 kfree+0x126/0x420 mm/slub.c:4580
 gsm_cleanup_mux+0x36c/0x7b0 drivers/tty/n_gsm.c:3160 [n_gsm]
 gsmld_ioctl+0x395/0x1450 drivers/tty/n_gsm.c:3408 [n_gsm]
 tty_ioctl+0x643/0x1100 drivers/tty/tty_io.c:2818

[Analysis]
gsm_msg on the tx_ctrl_list or tx_data_list of gsm_mux
can be freed by multi threads through ioctl,which leads
to the occurrence of uaf. Protect it by gsm tx lock.

Signed-off-by: Longlong Xia <xialonglong@kylinos.cn>
Cc: stable <stable@kernel.org>
Suggested-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240926130213.531959-1-xialonglong@kylinos.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-10-22 15:46:34 +02:00
Marek Vasut
c895d48c84 serial: imx: Update mctrl old_status on RTSD interrupt
commit 40d7903386 upstream.

When sending data using DMA at high baudrate (4 Mbdps in local test case) to
a device with small RX buffer which keeps asserting RTS after every received
byte, it is possible that the iMX UART driver would not recognize the falling
edge of RTS input signal and get stuck, unable to transmit any more data.

This condition happens when the following sequence of events occur:
- imx_uart_mctrl_check() is called at some point and takes a snapshot of UART
  control signal status into sport->old_status using imx_uart_get_hwmctrl().
  The RTSS/TIOCM_CTS bit is of interest here (*).
- DMA transfer occurs, the remote device asserts RTS signal after each byte.
  The i.MX UART driver recognizes each such RTS signal change, raises an
  interrupt with USR1 register RTSD bit set, which leads to invocation of
  __imx_uart_rtsint(), which calls uart_handle_cts_change().
  - If the RTS signal is deasserted, uart_handle_cts_change() clears
    port->hw_stopped and unblocks the port for further data transfers.
  - If the RTS is asserted, uart_handle_cts_change() sets port->hw_stopped
    and blocks the port for further data transfers. This may occur as the
    last interrupt of a transfer, which means port->hw_stopped remains set
    and the port remains blocked (**).
- Any further data transfer attempts will trigger imx_uart_mctrl_check(),
  which will read current status of UART control signals by calling
  imx_uart_get_hwmctrl() (***) and compare it with sport->old_status .
  - If current status differs from sport->old_status for RTS signal,
    uart_handle_cts_change() is called and possibly unblocks the port
    by clearing port->hw_stopped .
  - If current status does not differ from sport->old_status for RTS
    signal, no action occurs. This may occur in case prior snapshot (*)
    was taken before any transfer so the RTS is deasserted, current
    snapshot (***) was taken after a transfer and therefore RTS is
    deasserted again, which means current status and sport->old_status
    are identical. In case (**) triggered when RTS got asserted, and
    made port->hw_stopped set, the port->hw_stopped will remain set
    because no change on RTS line is recognized by this driver and
    uart_handle_cts_change() is not called from here to unblock the
    port->hw_stopped.

Update sport->old_status in __imx_uart_rtsint() accordingly to make
imx_uart_mctrl_check() detect such RTS change. Note that TIOCM_CAR
and TIOCM_RI bits in sport->old_status do not suffer from this problem.

Fixes: ceca629e0b ("[ARM] 2971/1: i.MX uart handle rts irq")
Cc: stable <stable@kernel.org>
Reviewed-by: Esben Haabendal <esben@geanix.com>
Signed-off-by: Marek Vasut <marex@denx.de>
Link: https://lore.kernel.org/r/20241002184133.19427-1-marex@denx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-10-22 15:46:33 +02:00
Jeongjun Park
dc2d5f0263 vt: prevent kernel-infoleak in con_font_get()
commit f956052e00 upstream.

font.data may not initialize all memory spaces depending on the implementation
of vc->vc_sw->con_font_get. This may cause info-leak, so to prevent this, it
is safest to modify it to initialize the allocated memory space to 0, and it
generally does not affect the overall performance of the system.

Cc: stable@vger.kernel.org
Reported-by: syzbot+955da2d57931604ee691@syzkaller.appspotmail.com
Fixes: 05e2600cb0 ("VT: Bump font size limitation to 64x128 pixels")
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
Link: https://lore.kernel.org/r/20241010174619.59662-1-aha310510@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-10-22 15:46:31 +02:00
Jiri Slaby (SUSE)
e418d91195 serial: protect uart_port_dtr_rts() in uart_shutdown() too
[ Upstream commit 602babaa84 ]

Commit af224ca2df (serial: core: Prevent unsafe uart port access, part
3) added few uport == NULL checks. It added one to uart_shutdown(), so
the commit assumes, uport can be NULL in there. But right after that
protection, there is an unprotected "uart_port_dtr_rts(uport, false);"
call. That is invoked only if HUPCL is set, so I assume that is the
reason why we do not see lots of these reports.

Or it cannot be NULL at this point at all for some reason :P.

Until the above is investigated, stay on the safe side and move this
dereference to the if too.

I got this inconsistency from Coverity under CID 1585130. Thanks.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20240805102046.307511-3-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-10-17 15:24:19 +02:00
Jiri Slaby (SUSE)
1d8c1add5e serial: don't use uninitialized value in uart_poll_init()
[ Upstream commit d0009a32c9 ]

Coverity reports (as CID 1536978) that uart_poll_init() passes
uninitialized pm_state to uart_change_pm(). It is in case the first 'if'
takes the true branch (does "goto out;").

Fix this and simplify the function by simple guard(mutex). The code
needs no labels after this at all. And it is pretty clear that the code
has not fiddled with pm_state at that point.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Fixes: 5e227ef2aa (serial: uart_poll_init() should power on the UART)
Cc: stable@vger.kernel.org
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20240805102046.307511-4-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-10-04 16:29:58 +02:00
Michael Trimarchi
88e26a196a tty: serial: kgdboc: Fix 8250_* kgdb over serial
[ Upstream commit 788aeef392 ]

Check if port type is not PORT_UNKNOWN during poll_init.
The kgdboc calls the tty_find_polling_driver that check
if the serial is able to use poll_init. The poll_init calls
the uart uart_poll_init that try to configure the uart with the
selected boot parameters. The uart must be ready before setting
parameters. Seems that PORT_UNKNOWN is already used by other
functions in serial_core to detect uart status, so use the same
to avoid to use it in invalid state.

The crash happen for instance in am62x architecture where the 8250
register the platform driver after the 8250 core is initialized.

Follow the report crash coming from KGDB

Thread 2 received signal SIGSEGV, Segmentation fault.
[Switching to Thread 1]
_outb (addr=<optimized out>, value=<optimized out>) at ./include/asm-generic/io.h:584
584		__raw_writeb(value, PCI_IOBASE + addr);
(gdb) bt

This section of the code is too early because in this case
the omap serial is not probed

Thread 2 received signal SIGSEGV, Segmentation fault.
[Switching to Thread 1]
_outb (addr=<optimized out>, value=<optimized out>) at ./include/asm-generic/io.h:584
584		__raw_writeb(value, PCI_IOBASE + addr);
(gdb) bt

Thread 2 received signal SIGSEGV, Segmentation fault.
[Switching to Thread 1]
_outb (addr=<optimized out>, value=<optimized out>) at ./include/asm-generic/io.h:584
584		__raw_writeb(value, PCI_IOBASE + addr);
(gdb) bt
0  _outb (addr=<optimized out>, value=<optimized out>) at ./include/asm-generic/io.h:584
1  logic_outb (value=0 '\000', addr=18446739675637874689) at lib/logic_pio.c:299
2  0xffff80008082dfcc in io_serial_out (p=0x0, offset=16760830, value=0) at drivers/tty/serial/8250/8250_port.c:416
3  0xffff80008082fe34 in serial_port_out (value=<optimized out>, offset=<optimized out>, up=<optimized out>)
    at ./include/linux/serial_core.h:677
4  serial8250_do_set_termios (port=0xffff8000828ee940 <serial8250_ports+1568>, termios=0xffff80008292b93c, old=0x0)
    at drivers/tty/serial/8250/8250_port.c:2860
5  0xffff800080830064 in serial8250_set_termios (port=0xfffffbfffe800000, termios=0xffbffe, old=0x0)
    at drivers/tty/serial/8250/8250_port.c:2912
6  0xffff80008082571c in uart_set_options (port=0xffff8000828ee940 <serial8250_ports+1568>, co=0x0, baud=115200, parity=110, bits=8, flow=110)
    at drivers/tty/serial/serial_core.c:2285
7  0xffff800080828434 in uart_poll_init (driver=0xfffffbfffe800000, line=16760830, options=0xffff8000828f7506 <config+6> "115200n8")
    at drivers/tty/serial/serial_core.c:2656
8  0xffff800080801690 in tty_find_polling_driver (name=0xffff8000828f7500 <config> "ttyS2,115200n8", line=0xffff80008292ba90)
    at drivers/tty/tty_io.c:410
9  0xffff80008086c0b0 in configure_kgdboc () at drivers/tty/serial/kgdboc.c:194
10 0xffff80008086c1ec in kgdboc_probe (pdev=0xfffffbfffe800000) at drivers/tty/serial/kgdboc.c:249
11 0xffff8000808b399c in platform_probe (_dev=0xffff000000ebb810) at drivers/base/platform.c:1404
12 0xffff8000808b0b44 in call_driver_probe (drv=<optimized out>, dev=<optimized out>) at drivers/base/dd.c:579
13 really_probe (dev=0xffff000000ebb810, drv=0xffff80008277f138 <kgdboc_platform_driver+48>) at drivers/base/dd.c:658
14 0xffff8000808b0d2c in __driver_probe_device (drv=0xffff80008277f138 <kgdboc_platform_driver+48>, dev=0xffff000000ebb810)
    at drivers/base/dd.c:800
15 0xffff8000808b0eb8 in driver_probe_device (drv=0xfffffbfffe800000, dev=0xffff000000ebb810) at drivers/base/dd.c:830
16 0xffff8000808b0ff4 in __device_attach_driver (drv=0xffff80008277f138 <kgdboc_platform_driver+48>, _data=0xffff80008292bc48)
    at drivers/base/dd.c:958
17 0xffff8000808ae970 in bus_for_each_drv (bus=0xfffffbfffe800000, start=0x0, data=0xffff80008292bc48,
    fn=0xffff8000808b0f3c <__device_attach_driver>) at drivers/base/bus.c:457
18 0xffff8000808b1408 in __device_attach (dev=0xffff000000ebb810, allow_async=true) at drivers/base/dd.c:1030
19 0xffff8000808b16d8 in device_initial_probe (dev=0xfffffbfffe800000) at drivers/base/dd.c:1079
20 0xffff8000808af9f4 in bus_probe_device (dev=0xffff000000ebb810) at drivers/base/bus.c:532
21 0xffff8000808ac77c in device_add (dev=0xfffffbfffe800000) at drivers/base/core.c:3625
22 0xffff8000808b3428 in platform_device_add (pdev=0xffff000000ebb800) at drivers/base/platform.c:716
23 0xffff800081b5dc0c in init_kgdboc () at drivers/tty/serial/kgdboc.c:292
24 0xffff800080014db0 in do_one_initcall (fn=0xffff800081b5dba4 <init_kgdboc>) at init/main.c:1236
25 0xffff800081b0114c in do_initcall_level (command_line=<optimized out>, level=<optimized out>) at init/main.c:1298
26 do_initcalls () at init/main.c:1314
27 do_basic_setup () at init/main.c:1333
28 kernel_init_freeable () at init/main.c:1551
29 0xffff8000810271ec in kernel_init (unused=0xfffffbfffe800000) at init/main.c:1441
30 0xffff800080015e80 in ret_from_fork () at arch/arm64/kernel/entry.S:857

Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com>
Link: https://lore.kernel.org/r/20231224131200.266224-1-michael@amarulasolutions.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: d0009a32c9 ("serial: don't use uninitialized value in uart_poll_init()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-10-04 16:29:58 +02:00
Johan Hovold
633bd1d6be serial: qcom-geni: fix fifo polling timeout
commit c80ee36ac8 upstream.

The qcom_geni_serial_poll_bit() can be used to wait for events like
command completion and is supposed to wait for the time it takes to
clear a full fifo before timing out.

As noted by Doug, the current implementation does not account for start,
stop and parity bits when determining the timeout. The helper also does
not currently account for the shift register and the two-word
intermediate transfer register.

A too short timeout can specifically lead to lost characters when
waiting for a transfer to complete as the transfer is cancelled on
timeout.

Instead of determining the poll timeout on every call, store the fifo
timeout when updating it in set_termios() and make sure to take the
shift and intermediate registers into account. Note that serial core has
already added a 20 ms margin to the fifo timeout.

Also note that the current uart_fifo_timeout() interface does
unnecessary calculations on every call and did not exist in earlier
kernels so only store its result once. This facilitates backports too as
earlier kernels can derive the timeout from uport->timeout, which has
since been removed.

Fixes: c4f528795d ("tty: serial: msm_geni_serial: Add serial driver support for GENI based QUP")
Cc: stable@vger.kernel.org	# 4.17
Reported-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/r/20240906131336.23625-2-johan+linaro@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-10-04 16:29:51 +02:00
Florian Fainelli
f7ba350f4e tty: rp2: Fix reset with non forgiving PCIe host bridges
commit f16dd10ba3 upstream.

The write to RP2_GLOBAL_CMD followed by an immediate read of
RP2_GLOBAL_CMD in rp2_reset_asic() is intented to flush out the write,
however by then the device is already in reset and cannot respond to a
memory cycle access.

On platforms such as the Raspberry Pi 4 and others using the
pcie-brcmstb.c driver, any memory access to a device that cannot respond
is met with a fatal system error, rather than being substituted with all
1s as is usually the case on PC platforms.

Swapping the delay and the read ensures that the device has finished
resetting before we attempt to read from it.

Fixes: 7d9f49afa4 ("serial: rp2: New driver for Comtrol RocketPort 2 cards")
Cc: stable <stable@kernel.org>
Suggested-by: Jim Quinlan <james.quinlan@broadcom.com>
Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://lore.kernel.org/r/20240906225435.707837-1-florian.fainelli@broadcom.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-10-04 16:29:51 +02:00
Markus Schneider-Pargmann
5060a1be93 serial: 8250: omap: Cleanup on error in request_irq
[ Upstream commit 35e648a160 ]

If devm_request_irq fails, the code does not cleanup many things that
were setup before. Instead of directly returning ret we should jump to
err.

Fixes: fef4f60031 ("serial: 8250: omap: Fix life cycle issues for interrupt handlers")
Signed-off-by: Markus Schneider-Pargmann <msp@baylibre.com>
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Tested-by: Kevin Hilman <khilman@baylibre.com>
Link: https://lore.kernel.org/r/20240807141227.1093006-4-msp@baylibre.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-10-04 16:29:40 +02:00
Mathieu Othacehe
63e80efa63 tty: atmel_serial: use the correct RTS flag.
commit c9f6613b16 upstream.

In RS485 mode, the RTS pin is driven high by hardware when the transmitter
is operating. This behaviour cannot be changed. This means that the driver
should claim that it supports SER_RS485_RTS_ON_SEND and not
SER_RS485_RTS_AFTER_SEND.

Otherwise, when configuring the port with the SER_RS485_RTS_ON_SEND, one
get the following warning:

kern.warning kernel: atmel_usart_serial atmel_usart_serial.2.auto:
ttyS1 (1): invalid RTS setting, using RTS_AFTER_SEND instead

which is contradictory with what's really happening.

Signed-off-by: Mathieu Othacehe <othacehe@gnu.org>
Cc: stable <stable@kernel.org>
Tested-by: Alexander Dahl <ada@thorsis.com>
Fixes: af47c491e3 ("serial: atmel: Fill in rs485_supported")
Link: https://lore.kernel.org/r/20240808060637.19886-1-othacehe@gnu.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-29 17:33:10 +02:00
Peng Fan
8eb92cfca6 tty: serial: fsl_lpuart: mark last busy before uart_add_one_port
commit dc98d76a15 upstream.

With "earlycon initcall_debug=1 loglevel=8" in bootargs, kernel
sometimes boot hang. It is because normal console still is not ready,
but runtime suspend is called, so early console putchar will hang
in waiting TRDE set in UARTSTAT.

The lpuart driver has auto suspend delay set to 3000ms, but during
uart_add_one_port, a child device serial ctrl will added and probed with
its pm runtime enabled(see serial_ctrl.c).
The runtime suspend call path is:
device_add
     |-> bus_probe_device
           |->device_initial_probe
	           |->__device_attach
                         |-> pm_runtime_get_sync(dev->parent);
			 |-> pm_request_idle(dev);
			 |-> pm_runtime_put(dev->parent);

So in the end, before normal console ready, the lpuart get runtime
suspended. And earlycon putchar will hang.

To address the issue, mark last busy just after pm_runtime_enable,
three seconds is long enough to switch from bootconsole to normal
console.

Fixes: 43543e6f53 ("tty: serial: fsl_lpuart: Add runtime pm support")
Cc: stable <stable@kernel.org>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Link: https://lore.kernel.org/r/20240808140325.580105-1-peng.fan@oss.nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-29 17:33:10 +02:00
George Kennedy
e3ad503876 serial: core: check uartclk for zero to avoid divide by zero
commit 6eabce6608 upstream.

Calling ioctl TIOCSSERIAL with an invalid baud_base can
result in uartclk being zero, which will result in a
divide by zero error in uart_get_divisor(). The check for
uartclk being zero in uart_set_info() needs to be done
before other settings are made as subsequent calls to
ioctl TIOCSSERIAL for the same port would be impacted if
the uartclk check was done where uartclk gets set.

Oops: divide error: 0000  PREEMPT SMP KASAN PTI
RIP: 0010:uart_get_divisor (drivers/tty/serial/serial_core.c:580)
Call Trace:
 <TASK>
serial8250_get_divisor (drivers/tty/serial/8250/8250_port.c:2576
    drivers/tty/serial/8250/8250_port.c:2589)
serial8250_do_set_termios (drivers/tty/serial/8250/8250_port.c:502
    drivers/tty/serial/8250/8250_port.c:2741)
serial8250_set_termios (drivers/tty/serial/8250/8250_port.c:2862)
uart_change_line_settings (./include/linux/spinlock.h:376
    ./include/linux/serial_core.h:608 drivers/tty/serial/serial_core.c:222)
uart_port_startup (drivers/tty/serial/serial_core.c:342)
uart_startup (drivers/tty/serial/serial_core.c:368)
uart_set_info (drivers/tty/serial/serial_core.c:1034)
uart_set_info_user (drivers/tty/serial/serial_core.c:1059)
tty_set_serial (drivers/tty/tty_io.c:2637)
tty_ioctl (drivers/tty/tty_io.c:2647 drivers/tty/tty_io.c:2791)
__x64_sys_ioctl (fs/ioctl.c:52 fs/ioctl.c:907
    fs/ioctl.c:893 fs/ioctl.c:893)
do_syscall_64 (arch/x86/entry/common.c:52
    (discriminator 1) arch/x86/entry/common.c:83 (discriminator 1))
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)

Reported-by: syzkaller <syzkaller@googlegroups.com>
Cc: stable@vger.kernel.org
Signed-off-by: George Kennedy <george.kennedy@oracle.com>
Rule: add
Link: https://lore.kernel.org/stable/1721148848-9784-1-git-send-email-george.kennedy%40oracle.com
Link: https://lore.kernel.org/r/1721219078-3209-1-git-send-email-george.kennedy@oracle.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-14 13:58:57 +02:00
Jacky Huang
23efa74cfe tty: serial: ma35d1: Add a NULL check for of_node
commit acd09ac253 upstream.

The pdev->dev.of_node can be NULL if the "serial" node is absent.
Add a NULL check to return an error in such cases.

Fixes: 930cbf92db ("tty: serial: Add Nuvoton ma35d1 serial driver support")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/all/8df7ce45-fd58-4235-88f7-43fe7cd67e8f@moroto.mountain/
Signed-off-by: Jacky Huang <ychuang3@nuvoton.com>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Cc: stable <stable@kernel.org>
Link: https://lore.kernel.org/r/20240625064128.127-1-ychuang570808@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-18 13:21:21 +02:00
Matthias Schiffer
b5f1844c05 serial: imx: Raise TX trigger level to 8
[ Upstream commit a3d8728ab0 ]

At the default TX trigger level of 2 in non-DMA mode (meaning that an
interrupt is generated when less than 2 characters are left in the
FIFO), we have observed frequent buffer underruns at 115200 Baud on an
i.MX8M Nano. This can cause communication issues if the receiving side
expects a continuous transfer.

Increasing the level to 8 makes the UART trigger an interrupt earlier,
giving the kernel enough time to refill the FIFO, at the cost of
triggering one interrupt per ~24 instead of ~30 bytes of transmitted
data (as the i.MX UART has a 32 byte FIFO).

Signed-off-by: Michael Krummsdorf <michael.krummsdorf@tq-group.com>
Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Link: https://lore.kernel.org/r/20240508133744.35858-1-matthias.schiffer@ew.tq-group.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-07-11 12:49:09 +02:00
Udit Kumar
18630d83b7 serial: 8250_omap: Fix Errata i2310 with RX FIFO level check
commit c128a1b052 upstream.

Errata i2310[0] says, Erroneous timeout can be triggered,
if this Erroneous interrupt is not cleared then it may leads
to storm of interrupts.

Commit 9d141c1e61 ("serial: 8250_omap: Implementation of Errata i2310")
which added the workaround but missed ensuring RX FIFO is really empty
before applying the errata workaround as recommended in the errata text.
Fix this by adding back check for UART_OMAP_RX_LVL to be 0 for
workaround to take effect.

[0] https://www.ti.com/lit/pdf/sprz536 page 23

Fixes: 9d141c1e61 ("serial: 8250_omap: Implementation of Errata i2310")
Cc: stable@vger.kernel.org
Reported-by: Vignesh Raghavendra <vigneshr@ti.com>
Closes: https://lore.kernel.org/all/e96d0c55-0b12-4cbf-9d23-48963543de49@ti.com/
Signed-off-by: Udit Kumar <u-kumar1@ti.com>
Link: https://lore.kernel.org/r/20240625160725.2102194-1-u-kumar1@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-05 09:34:07 +02:00
Stefan Eichenberger
633c861c0e serial: imx: only set receiver level if it is zero
commit 9706fc87b4 upstream.

With commit a81dbd0463 ("serial: imx: set receiver level before
starting uart") we set the receiver level to its default value. This
caused a regression when using SDMA, where the receiver level is 9
instead of 8 (default). This change will first check if the receiver
level is zero and only then set it to the default. This still avoids the
interrupt storm when the receiver level is zero.

Fixes: a81dbd0463 ("serial: imx: set receiver level before starting uart")
Cc: stable <stable@kernel.org>
Signed-off-by: Stefan Eichenberger <stefan.eichenberger@toradex.com>
Link: https://lore.kernel.org/r/20240703112543.148304-1-eichest@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-05 09:34:07 +02:00
Jean-Michel Hautbois
31020bea75 tty: mcf: MCF54418 has 10 UARTS
commit 7c92a8bd53 upstream.

Most of the colfires have up to 5 UARTs but MCF54418 has up-to 10 !
Change the maximum value authorized.

Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
Cc: stable <stable@kernel.org>
Fixes: 2545cf6e94 ("m68knommu: allow 4 coldfire serial ports")
Link: https://lore.kernel.org/r/20240620-upstream-uart-v1-1-a9d0d95fb19e@yoseli.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-05 09:34:00 +02:00
Jonas Gorski
d3ebc5597e serial: bcm63xx-uart: fix tx after conversion to uart_port_tx_limited()
commit ea55c65ded upstream.

When bcm63xx-uart was converted to uart_port_tx_limited(), it implicitly
added a call to stop_tx(). This causes garbage to be put out on the
serial console. To fix this, pass UART_TX_NOSTOP in flags, and manually
call stop_tx() ourselves analogue to how a similar issue was fixed in
commit 7be50f2e8f ("serial: mxs-auart: fix tx").

Fixes: d11cc8c3c4 ("tty: serial: use uart_port_tx_limited()")
Cc: stable@vger.kernel.org
Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
Signed-off-by: Doug Brown <doug@schmorgal.com>
Link: https://lore.kernel.org/r/20240606195632.173255-4-doug@schmorgal.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-05 09:34:00 +02:00
Stefan Eichenberger
d75b8ae150 serial: imx: set receiver level before starting uart
commit a81dbd0463 upstream.

Set the receiver level to something > 0 before calling imx_uart_start_rx
in rs485_config. This is necessary to avoid an interrupt storm that
might prevent the system from booting. This was seen on an i.MX7 device
when the rs485-rts-active-low property was active in the device tree.

Fixes: 6d215f83e5 ("serial: imx: warn user when using unsupported configuration")
Cc: stable <stable@kernel.org>
Signed-off-by: Stefan Eichenberger <stefan.eichenberger@toradex.com>
Link: https://lore.kernel.org/r/20240621153829.183780-1-eichest@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-05 09:34:00 +02:00
Udit Kumar
e67d7f3800 serial: 8250_omap: Implementation of Errata i2310
commit 9d141c1e61 upstream.

As per Errata i2310[0], Erroneous timeout can be triggered,
if this Erroneous interrupt is not cleared then it may leads
to storm of interrupts, therefore apply Errata i2310 solution.

[0] https://www.ti.com/lit/pdf/sprz536 page 23

Fixes: b67e830d38 ("serial: 8250: 8250_omap: Fix possible interrupt storm on K3 SoCs")
Cc: stable@vger.kernel.org
Signed-off-by: Udit Kumar <u-kumar1@ti.com>
Link: https://lore.kernel.org/r/20240619105903.165434-1-u-kumar1@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-05 09:33:59 +02:00
Andy Shevchenko
08cfaa1217 serial: 8250_dw: Revert "Move definitions to the shared header"
commit 2c94512055 upstream.

This reverts commit d9666dfb31.

The container of the struct dw8250_port_data is private to the actual
driver. In particular, 8250_lpss and 8250_dw use different data types
that are assigned to the UART port private_data. Hence, it must not
be used outside the specific driver.

Fix the mistake made in the past by moving the respective definitions
to the specific driver.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240514190730.2787071-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-27 13:49:13 +02:00
Linus Torvalds
287b569a5b tty: add the option to have a tty reject a new ldisc
[ Upstream commit 6bd23e0c2b ]

... and use it to limit the virtual terminals to just N_TTY.  They are
kind of special, and in particular, the "con_write()" routine violates
the "writes cannot sleep" rule that some ldiscs rely on.

This avoids the

   BUG: sleeping function called from invalid context at kernel/printk/printk.c:2659

when N_GSM has been attached to a virtual console, and gsmld_write()
calls con_write() while holding a spinlock, and con_write() then tries
to get the console lock.

Tested-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Daniel Starke <daniel.starke@siemens.com>
Reported-by: syzbot <syzbot+dbac96d8e73b61aa559c@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=dbac96d8e73b61aa559c
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20240423163339.59780-1-torvalds@linux-foundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-27 13:49:05 +02:00
Parker Newman
404fb6c4c8 serial: exar: adding missing CTI and Exar PCI ids
[ Upstream commit b86ae40ffc ]

- Added Connect Tech and Exar IDs not already in pci_ids.h

Signed-off-by: Parker Newman <pnewman@connecttech.com>
Link: https://lore.kernel.org/r/7c3d8e795a864dd9b0a00353b722060dc27c4e09.1713270624.git.pnewman@connecttech.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-27 13:49:04 +02:00
Esben Haabendal
982ae3376c serial: imx: Introduce timeout when waiting on transmitter empty
[ Upstream commit e533e4c62e ]

By waiting at most 1 second for USR2_TXDC to be set, we avoid a potential
deadlock.

In case of the timeout, there is not much we can do, so we simply ignore
the transmitter state and optimistically try to continue.

Signed-off-by: Esben Haabendal <esben@geanix.com>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/919647898c337a46604edcabaf13d42d80c0915d.1712837613.git.esben@geanix.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-27 13:49:04 +02:00
Andy Shevchenko
3a03ef31c1 serial: 8250_dw: Don't use struct dw8250_data outside of 8250_dw
[ Upstream commit 87d80bfbd5 ]

The container of the struct dw8250_port_data is private to the actual
driver. In particular, 8250_lpss and 8250_dw use different data types
that are assigned to the UART port private_data. Hence, it must not
be used outside the specific driver.

Currently the only cpr_val is required by the common code, make it
be available via struct dw8250_port_data.

This fixes the UART breakage on Intel Galileo boards.

Fixes: 593dea000b ("serial: 8250: dw: Allow to use a fallback CPR value if not synthesized")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240514190730.2787071-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21 14:38:49 +02:00
Andy Shevchenko
836e1a9fd8 serial: 8250_dw: Replace ACPI device check by a quirk
[ Upstream commit 173b097dcc ]

Instead of checking for APMC0D08 ACPI device presence,
use a quirk based on driver data.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240306143322.3291123-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 87d80bfbd5 ("serial: 8250_dw: Don't use struct dw8250_data outside of 8250_dw")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21 14:38:49 +02:00
Andy Shevchenko
1d98b6a0b9 serial: 8250_dw: Switch to use uart_read_port_properties()
[ Upstream commit e6a46d073e ]

Since we have now a common helper to read port properties
use it instead of sparse home grown solution.

Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240304123035.758700-8-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 87d80bfbd5 ("serial: 8250_dw: Don't use struct dw8250_data outside of 8250_dw")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21 14:38:49 +02:00
Andy Shevchenko
f59e2391d3 serial: port: Introduce a common helper to read properties
[ Upstream commit e894b6005d ]

Several serial drivers want to read the same or similar set of
the port properties. Make a common helper for them.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240304123035.758700-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 87d80bfbd5 ("serial: 8250_dw: Don't use struct dw8250_data outside of 8250_dw")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21 14:38:49 +02:00
Doug Brown
72b5c7f3b3 serial: 8250_pxa: Configure tx_loadsz to match FIFO IRQ level
commit 5208e7ced5 upstream.

The FIFO is 64 bytes, but the FCR is configured to fire the TX interrupt
when the FIFO is half empty (bit 3 = 0). Thus, we should only write 32
bytes when a TX interrupt occurs.

This fixes a problem observed on the PXA168 that dropped a bunch of TX
bytes during large transmissions.

Fixes: ab28f51c77 ("serial: rewrite pxa2xx-uart to use 8250_core")
Signed-off-by: Doug Brown <doug@schmorgal.com>
Link: https://lore.kernel.org/r/20240519191929.122202-1-doug@schmorgal.com
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-21 14:38:46 +02:00
Douglas Anderson
3380fa014a serial: port: Don't block system suspend even if bytes are left to xmit
commit ca84cd379b upstream.

Recently, suspend testing on sc7180-trogdor based devices has started
to sometimes fail with messages like this:

  port a88000.serial:0.0: PM: calling pm_runtime_force_suspend+0x0/0xf8 @ 28934, parent: a88000.serial:0
  port a88000.serial:0.0: PM: dpm_run_callback(): pm_runtime_force_suspend+0x0/0xf8 returns -16
  port a88000.serial:0.0: PM: pm_runtime_force_suspend+0x0/0xf8 returned -16 after 33 usecs
  port a88000.serial:0.0: PM: failed to suspend: error -16

I could reproduce these problems by logging in via an agetty on the
debug serial port (which was _not_ used for kernel console) and
running:
  cat /var/log/messages
...and then (via an SSH session) forcing a few suspend/resume cycles.

Tracing through the code and doing some printf()-based debugging shows
that the -16 (-EBUSY) comes from the recently added
serial_port_runtime_suspend().

The idea of the serial_port_runtime_suspend() function is to prevent
the port from being _runtime_ suspended if it still has bytes left to
transmit. Having bytes left to transmit isn't a reason to block
_system_ suspend, though. If a serdev device in the kernel needs to
block system suspend it should block its own suspend and it can use
serdev_device_wait_until_sent() to ensure bytes are sent.

The DEFINE_RUNTIME_DEV_PM_OPS() used by the serial_port code means
that the system suspend function will be pm_runtime_force_suspend().
In pm_runtime_force_suspend() we can see that before calling the
runtime suspend function we'll call pm_runtime_disable(). This should
be a reliable way to detect that we're called from system suspend and
that we shouldn't look for busyness.

Fixes: 43066e3222 ("serial: port: Don't suspend if the port is still busy")
Cc: stable@vger.kernel.org
Reviewed-by: Tony Lindgren <tony.lindgren@linux.intel.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20240531080914.v3.1.I2395e66cf70c6e67d774c56943825c289b9c13e4@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-21 14:38:24 +02:00
Ilpo Järvinen
b895a1b981 tty: n_tty: Fix buffer offsets when lookahead is used
commit b19ab7ee2c upstream.

When lookahead has "consumed" some characters (la_count > 0),
n_tty_receive_buf_standard() and n_tty_receive_buf_closing() for
characters beyond the la_count are given wrong cp/fp offsets which
leads to duplicating and losing some characters.

If la_count > 0, correct buffer pointers and make count consistent too
(the latter is not strictly necessary to fix the issue but seems more
logical to adjust all variables immediately to keep state consistent).

Reported-by: Vadym Krevs <vkrevs@yahoo.com>
Fixes: 6bb6fa6908 ("tty: Implement lookahead to process XON/XOFF timely")
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218834
Tested-by: Vadym Krevs <vkrevs@yahoo.com>
Cc: stable@vger.kernel.org
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20240514140429.12087-1-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-21 14:38:24 +02:00
Hugo Villeneuve
11244a4328 serial: sc16is7xx: fix bug in sc16is7xx_set_baud() when using prescaler
[ Upstream commit 8492bd91aa ]

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: dfeae619d7 ("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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:12:35 +02:00
Hugo Villeneuve
f0eb53ffd8 serial: sc16is7xx: replace hardcoded divisor value with BIT() macro
[ Upstream commit 2e57cefc44 ]

To better show why the limit is what it is, since we have only 16 bits for
the divisor.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20231221231823.2327894-13-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 8492bd91aa ("serial: sc16is7xx: fix bug in sc16is7xx_set_baud() when using prescaler")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:12:35 +02:00
Wolfram Sang
70d6dca403 serial: sh-sci: protect invalidating RXDMA on shutdown
[ Upstream commit aae20f6e34 ]

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: 2c4ee23530 ("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>
2024-06-12 11:12:30 +02:00
Hugo Villeneuve
3431d265ea serial: sc16is7xx: add proper sched.h include for sched_set_fifo()
[ Upstream commit 2a8e4ab0c9 ]

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

Fixes: 28d2f209cd ("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>
2024-06-12 11:12:17 +02:00
Andy Shevchenko
749603af8f serial: max3100: Fix bitwise types
[ Upstream commit e60955dbec ]

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: 7831d56b0a ("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>
2024-06-12 11:12:17 +02:00
Andy Shevchenko
e8a10089ed serial: max3100: Update uart_driver_registered on driver removal
[ Upstream commit 712a1fcb38 ]

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: 7831d56b0a ("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>
2024-06-12 11:12:17 +02:00
Andy Shevchenko
93df2fba6c serial: max3100: Lock port->lock when calling uart_handle_cts_change()
[ Upstream commit 77ab53371a ]

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: 7831d56b0a ("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>
2024-06-12 11:12:17 +02:00
Pin-yen Lin
e4a1d0aa0d serial: 8520_mtk: Set RTS on shutdown for Rx in-band wakeup
commit 4244f830a5 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: 18c9d4a3c2 ("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>
2024-06-12 11:11:18 +02:00
Doug Berger
7e16930d46 serial: 8250_bcm7271: use default_mux_rate if possible
commit 614a19b89c 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: 41a469482d ("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>
2024-06-12 11:11:18 +02:00
Daniel Starke
62c3763dcb tty: n_gsm: fix missing receive state reset after mode switch
commit 70d7f1427a upstream.

The current implementation uses either gsm0_receive() or gsm1_receive()
depending on whether the user configured the mux in basic or advanced
option mode. Both functions share some state values over the same logical
elements of the frame. However, both frame types differ in their nature.
gsm0_receive() uses non-transparency framing, whereas gsm1_receive() uses
transparency mechanism. Switching between both modes leaves the receive
function in an undefined state when done during frame reception.

Fix this by splitting both states. Add gsm0_receive_state_check_and_fix()
and gsm1_receive_state_check_and_fix() to ensure that gsm->state is reset
after a change of gsm->receive.

Note that gsm->state is only accessed in:
- gsm0_receive()
- gsm1_receive()
- gsm_error()

Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20240424054842.7741-2-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-12 11:11:18 +02:00
Daniel Starke
774d83b008 tty: n_gsm: fix possible out-of-bounds in gsm0_receive()
commit 47388e807f upstream.

Assuming the following:
- side A configures the n_gsm in basic option mode
- side B sends the header of a basic option mode frame with data length 1
- side A switches to advanced option mode
- side B sends 2 data bytes which exceeds gsm->len
  Reason: gsm->len is not used in advanced option mode.
- side A switches to basic option mode
- side B keeps sending until gsm0_receive() writes past gsm->buf
  Reason: Neither gsm->state nor gsm->len have been reset after
  reconfiguration.

Fix this by changing gsm->count to gsm->len comparison from equal to less
than. Also add upper limit checks against the constant MAX_MRU in
gsm0_receive() and gsm1_receive() to harden against memory corruption of
gsm->len and gsm->mru.

All other checks remain as we still need to limit the data according to the
user configuration and actual payload size.

Reported-by: j51569436@gmail.com
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218708
Tested-by: j51569436@gmail.com
Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20240424054842.7741-1-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-12 11:11:18 +02:00
Daniel Thompson
642069561e serial: kgdboc: Fix NMI-safety problems from keyboard reset code
commit b2aba15ad6 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>
2024-05-25 16:22:54 +02:00
Tony Lindgren
83290f9f07 serial: core: Fix missing shutdown and startup for serial base port
commit 1aa4ad4eb6 upstream.

We are seeing start_tx being called after port shutdown as noted by Jiri.
This happens because we are missing the startup and shutdown related
functions for the serial base port.

Let's fix the issue by adding startup and shutdown functions for the
serial base port to block tx flushing for the serial base port when the
port is not in use.

Fixes: 84a9582fd2 ("serial: core: Start managing serial controllers to enable runtime PM")
Cc: stable <stable@kernel.org>
Reported-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20240411055848.38190-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-27 17:11:39 +02:00
Andy Shevchenko
7ae7104d54 serial: core: Clearing the circular buffer before NULLifying it
commit 9cf7ea2eeb upstream.

The circular buffer is NULLified in uart_tty_port_shutdown()
under the spin lock. However, the PM or other timer based callbacks
may still trigger after this event without knowning that buffer pointer
is not valid. Since the serial code is a bit inconsistent in checking
the buffer state (some rely on the head-tail positions, some on the
buffer pointer), it's better to have both aligned, i.e. buffer pointer
to be NULL and head-tail possitions to be the same, meaning it's empty.
This will prevent asynchronous calls to dereference NULL pointer as
reported recently in 8250 case:

  BUG: kernel NULL pointer dereference, address: 00000cf5
  Workqueue: pm pm_runtime_work
  EIP: serial8250_tx_chars (drivers/tty/serial/8250/8250_port.c:1809)
  ...
  ? serial8250_tx_chars (drivers/tty/serial/8250/8250_port.c:1809)
  __start_tx (drivers/tty/serial/8250/8250_port.c:1551)
  serial8250_start_tx (drivers/tty/serial/8250/8250_port.c:1654)
  serial_port_runtime_suspend (include/linux/serial_core.h:667 drivers/tty/serial/serial_port.c:63)
  __rpm_callback (drivers/base/power/runtime.c:393)
  ? serial_port_remove (drivers/tty/serial/serial_port.c:50)
  rpm_suspend (drivers/base/power/runtime.c:447)

The proposed change will prevent ->start_tx() to be called during
suspend on shut down port.

Fixes: 43066e3222 ("serial: port: Don't suspend if the port is still busy")
Cc: stable <stable@kernel.org>
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202404031607.2e92eebe-lkp@intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240404150034.41648-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-27 17:11:39 +02:00