summaryrefslogtreecommitdiff
path: root/drivers/tty
AgeCommit message (Collapse)AuthorFilesLines
2024-04-17serial: stm32: Reset .throttled state in .startup()Uwe Kleine-König1-0/+1
When an UART is opened that still has .throttled set from a previous open, the RX interrupt is enabled but the irq handler doesn't consider it. This easily results in a stuck irq with the effect to occupy the CPU in a tight loop. So reset the throttle state in .startup() to ensure that RX irqs are handled. Fixes: d1ec8a2eabe9 ("serial: stm32: update throttle and unthrottle ops for dma mode") Cc: stable@vger.kernel.org Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/a784f80d3414f7db723b2ec66efc56e1ad666cbf.1713344161.git.u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-17serial: stm32: Return IRQ_NONE in the ISR if no handling happendUwe Kleine-König1-2/+10
If there is a stuck irq that the handler doesn't address, returning IRQ_HANDLED unconditionally makes it impossible for the irq core to detect the problem and disable the irq. So only return IRQ_HANDLED if an event was handled. A stuck irq is still problematic, but with this change at least it only makes the UART nonfunctional instead of occupying the (usually only) CPU by 100% and so stall the whole machine. Fixes: 48a6092fb41f ("serial: stm32-usart: Add STM32 USART Driver") Cc: stable@vger.kernel.org Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/5f92603d0dfd8a5b8014b2b10a902d91e0bb881f.1713344161.git.u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-11serial: core: Fix missing shutdown and startup for serial base portTony Lindgren3-3/+55
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: 84a9582fd203 ("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>
2024-04-09serial: core: Clearing the circular buffer before NULLifying itAndy Shevchenko1-0/+1
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: 43066e32227e ("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>
2024-04-09serial/pmac_zilog: Remove flawed mitigation for rx irq floodFinn Thain1-14/+0
The mitigation was intended to stop the irq completely. That may be better than a hard lock-up but it turns out that you get a crash anyway if you're using pmac_zilog as a serial console: ttyPZ0: pmz: rx irq flood ! BUG: spinlock recursion on CPU#0, swapper/0 That's because the pr_err() call in pmz_receive_chars() results in pmz_console_write() attempting to lock a spinlock already locked in pmz_interrupt(). With CONFIG_DEBUG_SPINLOCK=y, this produces a fatal BUG splat. The spinlock in question is the one in struct uart_port. Even when it's not fatal, the serial port rx function ceases to work. Also, the iteration limit doesn't play nicely with QEMU, as can be seen in the bug report linked below. A web search for other reports of the error message "pmz: rx irq flood" didn't produce anything. So I don't think this code is needed any more. Remove it. Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Aneesh Kumar K.V <aneesh.kumar@kernel.org> Cc: Naveen N. Rao <naveen.n.rao@linux.ibm.com> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Cc: stable@kernel.org Cc: linux-m68k@lists.linux-m68k.org Link: https://github.com/vivier/qemu-m68k/issues/44 Link: https://lore.kernel.org/all/1078874617.9746.36.camel@gaston/ Acked-by: Michael Ellerman <mpe@ellerman.id.au> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable <stable@kernel.org> Signed-off-by: Finn Thain <fthain@linux-m68k.org> Link: https://lore.kernel.org/r/e853cf2c762f23101cd2ddec0cc0c2be0e72685f.1712568223.git.fthain@linux-m68k.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-09serial: 8250_pci: Remove redundant PCI IDsAndy Shevchenko1-6/+0
Driver complains that PCI IDs are not needed for some of the LAVA cards: [ 0.297252] serial 0000:04:00.0: Redundant entry in serial pci_table. [ 0.297252] Please send the output of lspci -vv, this [ 0.297252] message (0x1407,0x0120,0x0000,0x0000), the [ 0.297252] manufacturer and name of serial board or [ 0.297252] modem board to <linux-serial@vger.kernel.org>. Do as suggested. Reported-by: Jimmy A <jimand04@hotmail.com> Closes: https://lore.kernel.org/r/VI1P194MB052751BE157EFE9CEAB75725CE362@VI1P194MB0527.EURP194.PROD.OUTLOOK.COM Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com> Link: https://lore.kernel.org/r/20240403224152.945099-1-andy.shevchenko@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-09serial: core: Fix regression when runtime PM is not enabledTony Lindgren1-1/+1
Commit 45a3a8ef8129 ("serial: core: Revert checks for tx runtime PM state") caused a regression for Sun Ultra 60 for the sunsab driver as reported by Nick Bowler <nbowler@draconx.ca>. We need to add back the check runtime PM enabled state for serial port controller device, I wrongly assumed earlier we could just remove it. Fixes: 45a3a8ef8129 ("serial: core: Revert checks for tx runtime PM state") Cc: stable <stable@kernel.org> Reported-by: Nick Bowler <nbowler@draconx.ca> Signed-off-by: Tony Lindgren <tony@atomide.com> Link: https://lore.kernel.org/r/20240325071649.27040-1-tony@atomide.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-09serial: mxs-auart: add spinlock around changing cts stateEmil Kronborg1-2/+6
The uart_handle_cts_change() function in serial_core expects the caller to hold uport->lock. For example, I have seen the below kernel splat, when the Bluetooth driver is loaded on an i.MX28 board. [ 85.119255] ------------[ cut here ]------------ [ 85.124413] WARNING: CPU: 0 PID: 27 at /drivers/tty/serial/serial_core.c:3453 uart_handle_cts_change+0xb4/0xec [ 85.134694] Modules linked in: hci_uart bluetooth ecdh_generic ecc wlcore_sdio configfs [ 85.143314] CPU: 0 PID: 27 Comm: kworker/u3:0 Not tainted 6.6.3-00021-gd62a2f068f92 #1 [ 85.151396] Hardware name: Freescale MXS (Device Tree) [ 85.156679] Workqueue: hci0 hci_power_on [bluetooth] (...) [ 85.191765] uart_handle_cts_change from mxs_auart_irq_handle+0x380/0x3f4 [ 85.198787] mxs_auart_irq_handle from __handle_irq_event_percpu+0x88/0x210 (...) Cc: stable@vger.kernel.org Fixes: 4d90bb147ef6 ("serial: core: Document and assert lock requirements for irq helpers") Reviewed-by: Frank Li <Frank.Li@nxp.com> Signed-off-by: Emil Kronborg <emil.kronborg@protonmail.com> Link: https://lore.kernel.org/r/20240320121530.11348-1-emil.kronborg@protonmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-09serial: 8250_dw: Revert: Do not reclock if already at correct rateHans de Goede1-3/+3
Commit e5d6bd25f93d ("serial: 8250_dw: Do not reclock if already at correct rate") breaks the dw UARTs on Intel Bay Trail (BYT) and Cherry Trail (CHT) SoCs. Before this change the RTL8732BS Bluetooth HCI which is found connected over the dw UART on both BYT and CHT boards works properly: Bluetooth: hci0: RTL: examining hci_ver=06 hci_rev=000b lmp_ver=06 lmp_subver=8723 Bluetooth: hci0: RTL: rom_version status=0 version=1 Bluetooth: hci0: RTL: loading rtl_bt/rtl8723bs_fw.bin Bluetooth: hci0: RTL: loading rtl_bt/rtl8723bs_config-OBDA8723.bin Bluetooth: hci0: RTL: cfg_sz 64, total sz 24508 Bluetooth: hci0: RTL: fw version 0x365d462e where as after this change probing it fails: Bluetooth: hci0: RTL: examining hci_ver=06 hci_rev=000b lmp_ver=06 lmp_subver=8723 Bluetooth: hci0: RTL: rom_version status=0 version=1 Bluetooth: hci0: RTL: loading rtl_bt/rtl8723bs_fw.bin Bluetooth: hci0: RTL: loading rtl_bt/rtl8723bs_config-OBDA8723.bin Bluetooth: hci0: RTL: cfg_sz 64, total sz 24508 Bluetooth: hci0: command 0xfc20 tx timeout Bluetooth: hci0: RTL: download fw command failed (-110) Revert the changes to fix this regression. Fixes: e5d6bd25f93d ("serial: 8250_dw: Do not reclock if already at correct rate") Cc: stable@vger.kernel.org Cc: Peter Collingbourne <pcc@google.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Peter Collingbourne <pcc@google.com> Link: https://lore.kernel.org/r/20240317214123.34482-1-hdegoede@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-09serial: 8250_lpc18xx: disable clks on error in probe()Dan Carpenter1-1/+1
Goto the clean up path to clean up a couple clocks before returning on this error path. Fixes: 0087b9e694ee ("serial: 8250_lpc18xx: Switch to use uart_read_port_properties()") Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/92646c10-e0b5-4117-a9ac-ce9987d33ce3@moroto.mountain Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-21Merge tag 'tty-6.9-rc1' of ↵Linus Torvalds55-2018/+2440
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty / serial driver updates from Greg KH: "Here is the big set of TTY/Serial driver updates and cleanups for 6.9-rc1. Included in here are: - more tty cleanups from Jiri - loads of 8250 driver cleanups from Andy - max310x driver updates - samsung serial driver updates - uart_prepare_sysrq_char() updates for many drivers - platform driver remove callback void cleanups - stm32 driver updates - other small tty/serial driver updates All of these have been in linux-next for a long time with no reported issues" * tag 'tty-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (199 commits) dt-bindings: serial: stm32: add power-domains property serial: 8250_dw: Replace ACPI device check by a quirk serial: Lock console when calling into driver before registration serial: 8250_uniphier: Switch to use uart_read_port_properties() serial: 8250_tegra: Switch to use uart_read_port_properties() serial: 8250_pxa: Switch to use uart_read_port_properties() serial: 8250_omap: Switch to use uart_read_port_properties() serial: 8250_of: Switch to use uart_read_port_properties() serial: 8250_lpc18xx: Switch to use uart_read_port_properties() serial: 8250_ingenic: Switch to use uart_read_port_properties() serial: 8250_dw: Switch to use uart_read_port_properties() serial: 8250_bcm7271: Switch to use uart_read_port_properties() serial: 8250_bcm2835aux: Switch to use uart_read_port_properties() serial: 8250_aspeed_vuart: Switch to use uart_read_port_properties() serial: port: Introduce a common helper to read properties serial: core: Add UPIO_UNKNOWN constant for unknown port type serial: core: Move struct uart_port::quirks closer to possible values serial: sh-sci: Call sci_serial_{in,out}() directly serial: core: only stop transmit when HW fifo is empty serial: pch: Use uart_prepare_sysrq_char(). ...
2024-03-16Merge tag 'powerpc-6.9-1' of ↵Linus Torvalds1-5/+2
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Add AT_HWCAP3 and AT_HWCAP4 aux vector entries for future use by glibc - Add support for recognising the Power11 architected and raw PVRs - Add support for nr_cpus=n on the command line where the boot CPU is >= n - Add ppcxx_allmodconfig targets for all 32-bit sub-arches - Other small features, cleanups and fixes Thanks to Akanksha J N, Brian King, Christophe Leroy, Dawei Li, Geoff Levand, Greg Kroah-Hartman, Jan-Benedict Glaw, Kajol Jain, Kunwu Chan, Li zeming, Madhavan Srinivasan, Masahiro Yamada, Nathan Chancellor, Nicholas Piggin, Peter Bergner, Qiheng Lin, Randy Dunlap, Ricardo B. Marliere, Rob Herring, Sathvika Vasireddy, Shrikanth Hegde, Uwe Kleine-König, Vaibhav Jain, and Wen Xiong. * tag 'powerpc-6.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (71 commits) powerpc/macio: Make remove callback of macio driver void returned powerpc/83xx: Fix build failure with FPU=n powerpc/64s: Fix get_hugepd_cache_index() build failure powerpc/4xx: Fix warp_gpio_leds build failure powerpc/amigaone: Make several functions static powerpc/embedded6xx: Fix no previous prototype for avr_uart_send() etc. macintosh/adb: make adb_dev_class constant powerpc: xor_vmx: Add '-mhard-float' to CFLAGS powerpc/fsl: Fix mfpmr() asm constraint error powerpc: Remove cpu-as-y completely powerpc/fsl: Modernise mt/mfpmr powerpc/fsl: Fix mfpmr build errors with newer binutils powerpc/64s: Use .machine power4 around dcbt powerpc/64s: Move dcbt/dcbtst sequence into a macro powerpc/mm: Code cleanup for __hash_page_thp powerpc/hv-gpci: Fix the H_GET_PERF_COUNTER_INFO hcall return value checks powerpc/irq: Allow softirq to hardirq stack transition powerpc: Stop using of_root powerpc/machdep: Define 'compatibles' property in ppc_md and use it of: Reimplement of_machine_is_compatible() using of_machine_compatible_match() ...
2024-03-15Merge tag 'mips_6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linuxLinus Torvalds1-1/+1
Pull MIPS updates from Thomas Bogendoerfer: - added support for Mobileye SoCs - unified GPR/CP0 regs handling for uasm - cleanups and fixes * tag 'mips_6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (56 commits) mips: cm: Convert __mips_cm_phys_base() to weak function mips: cm: Convert __mips_cm_l2sync_phys_base() to weak function mips: dts: ralink: mt7621: add cell count properties to usb mips: dts: ralink: mt7621: add serial1 and serial2 nodes mips: dts: ralink: mt7621: reorder serial0 properties mips: dts: ralink: mt7621: associate uart1_pins with serial0 MIPS: ralink: Don't use "proxy" headers mips: sibyte: make tb_class constant mips: mt: make mt_class constant MIPS: ralink: Remove unused of_gpio.h bus: bt1-apb: Remove duplicate include MAINTAINERS: remove entry to non-existing file in MOBILEYE MIPS SOCS MIPS: mipsregs: Parse fp and sp register by name in parse_r tty: mips_ejtag_fdc: Fix passing incompatible pointer type warning mips: zboot: Fix "no previous prototype" build warning MIPS: mipsregs: Set proper ISA level for virt extensions MIPS: Implement microMIPS MT ASE helpers MIPS: Limit MIPS_MT_SMP support by ISA reversion MIPS: Loongson64: test for -march=loongson3a cflag MIPS: BMIPS: Drop unnecessary assembler flag ...
2024-03-07powerpc/macio: Make remove callback of macio driver void returnedDawei Li1-5/+2
Commit fc7a6209d571 ("bus: Make remove callback return void") forces bus_type::remove be void-returned, it doesn't make much sense for any bus based driver implementing remove callbalk to return non-void to its caller. This change is for macio bus based drivers. Signed-off-by: Dawei Li <set_pte_at@outlook.com> Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Acked-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/TYCP286MB232391520CB471E7C8D6EA84CAD19@TYCP286MB2323.JPNP286.PROD.OUTLOOK.COM
2024-03-07serial: 8250_dw: Replace ACPI device check by a quirkAndy Shevchenko1-25/+26
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>
2024-03-05Revert "tty: serial: simplify qcom_geni_serial_send_chunk_fifo()"Douglas Anderson1-4/+6
This reverts commit 5c7e105cd156fc9adf5294a83623d7a40c15f9b9. As identified by KASAN, the simplification done by the cleanup patch was not legal. >From tracing through the code, it can be seen that we're transmitting from a 4096-byte circular buffer. We copy anywhere from 1-4 bytes from it each time. The simplification runs into trouble when we get near the end of the circular buffer. For instance, we might start out with xmit->tail = 4094 and we want to transfer 4 bytes. With the code before simplification this was no problem. We'd read buf[4094], buf[4095], buf[0], and buf[1]. With the new code we'll do a memcpy(&buf[4094], 4) which reads 2 bytes past the end of the buffer and then skips transmitting what's at buf[0] and buf[1]. KASAN isn't 100% consistent at reporting this for me, but to be extra confident in the analysis, I added traces of the tail and tx_bytes and then wrote a test program: while true; do echo -n "abcdefghijklmnopqrstuvwxyz0" > /dev/ttyMSM0 sleep .1 done I watched the traces over SSH and saw: qcom_geni_serial_send_chunk_fifo: 4093 4 qcom_geni_serial_send_chunk_fifo: 1 3 Which indicated that one byte should be missing. Sure enough the output that should have been: abcdefghijklmnopqrstuvwxyz0 In one case was actually missing a byte: abcdefghijklmnopqrstuvwyz0 Running "ls -al" on large directories also made the missing bytes obvious since columns didn't line up. While the original code may not be the most elegant, we only talking about copying up to 4 bytes here. Let's just go back to the code that worked. Fixes: 5c7e105cd156 ("tty: serial: simplify qcom_geni_serial_send_chunk_fifo()") Cc: stable <stable@kernel.org> Signed-off-by: Douglas Anderson <dianders@chromium.org> Acked-by: Jiri Slaby <jirislaby@kernel.org> Tested-by: Johan Hovold <johan+linaro@kernel.org> Link: https://lore.kernel.org/r/20240304174952.1.I920a314049b345efd1f69d708e7f74d2213d0b49@changeid Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-05tty: serial: fsl_lpuart: avoid idle preamble pending if CTS is enabledSherry Sun1-2/+5
If the remote uart device is not connected or not enabled after booting up, the CTS line is high by default. At this time, if we enable the flow control when opening the device(for example, using “stty -F /dev/ttyLP4 crtscts” command), there will be a pending idle preamble(first writing 0 and then writing 1 to UARTCTRL_TE will queue an idle preamble) that cannot be sent out, resulting in the uart port fail to close(waiting for TX empty), so the user space stty will have to wait for a long time or forever. This is an LPUART IP bug(idle preamble has higher priority than CTS), here add a workaround patch to enable TX CTS after enabling UARTCTRL_TE, so that the idle preamble does not get stuck due to CTS is deasserted. 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> Reviewed-by: Alexander Sverdlin <alexander.sverdlin@siemens.com> Link: https://lore.kernel.org/r/20240305015706.1050769-1-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-05serial: Lock console when calling into driver before registrationPeter Collingbourne2-6/+12
During the handoff from earlycon to the real console driver, we have two separate drivers operating on the same device concurrently. In the case of the 8250 driver these concurrent accesses cause problems due to the driver's use of banked registers, controlled by LCR.DLAB. It is possible for the setup(), config_port(), pm() and set_mctrl() callbacks to set DLAB, which can cause the earlycon code that intends to access TX to instead access DLL, leading to missed output and corruption on the serial line due to unintended modifications to the baud rate. In particular, for setup() we have: univ8250_console_setup() -> serial8250_console_setup() -> uart_set_options() -> serial8250_set_termios() -> serial8250_do_set_termios() -> serial8250_do_set_divisor() For config_port() we have: serial8250_config_port() -> autoconfig() For pm() we have: serial8250_pm() -> serial8250_do_pm() -> serial8250_set_sleep() For set_mctrl() we have (for some devices): serial8250_set_mctrl() -> omap8250_set_mctrl() -> __omap8250_set_mctrl() To avoid such problems, let's make it so that the console is locked during pre-registration calls to these callbacks, which will prevent the earlycon driver from running concurrently. Remove the partial solution to this problem in the 8250 driver that locked the console only during autoconfig_irq(), as this would result in a deadlock with the new approach. The console continues to be locked during autoconfig_irq() because it can only be called through uart_configure_port(). Although this patch introduces more locking than strictly necessary (and in particular it also locks during the call to rs485_config() which is not affected by this issue as far as I can tell), it follows the principle that it is the responsibility of the generic console code to manage the earlycon handoff by ensuring that earlycon and real console driver code cannot run concurrently, and not the individual drivers. Signed-off-by: Peter Collingbourne <pcc@google.com> Reviewed-by: John Ogness <john.ogness@linutronix.de> Link: https://linux-review.googlesource.com/id/I7cf8124dcebf8618e6b2ee543fa5b25532de55d8 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240304214350.501253-1-pcc@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-05serial: 8250_uniphier: Switch to use uart_read_port_properties()Andy Shevchenko1-13/+4
Since we have now a common helper to read port properties use it instead of sparse home grown solution. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com> Tested-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com> Link: https://lore.kernel.org/r/20240304123035.758700-15-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-05serial: 8250_tegra: Switch to use uart_read_port_properties()Andy Shevchenko1-17/+9
Since we have now a common helper to read port properties use it instead of sparse home grown solution. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20240304123035.758700-14-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-05serial: 8250_pxa: Switch to use uart_read_port_properties()Andy Shevchenko1-13/+9
Since we have now a common helper to read port properties use it instead of sparse home grown solution. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20240304123035.758700-13-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-05serial: 8250_omap: Switch to use uart_read_port_properties()Andy Shevchenko1-19/+10
Since we have now a common helper to read port properties use it instead of sparse home grown solution. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20240304123035.758700-12-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-05serial: 8250_of: Switch to use uart_read_port_properties()Andy Shevchenko1-80/+19
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> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com> Tested-by: Florian Fainelli <florian.fainelli@broadcom.com> Link: https://lore.kernel.org/r/20240304123035.758700-11-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-05serial: 8250_lpc18xx: Switch to use uart_read_port_properties()Andy Shevchenko1-12/+8
Since we have now a common helper to read port properties use it instead of sparse home grown solution. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20240304123035.758700-10-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-05serial: 8250_ingenic: Switch to use uart_read_port_properties()Andy Shevchenko1-13/+7
Since we have now a common helper to read port properties use it instead of sparse home grown solution. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20240304123035.758700-9-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-05serial: 8250_dw: Switch to use uart_read_port_properties()Andy Shevchenko1-40/+27
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>
2024-03-05serial: 8250_bcm7271: Switch to use uart_read_port_properties()Andy Shevchenko1-37/+19
Since we have now a common helper to read port properties use it instead of sparse home grown solution. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com> Tested-by: Florian Fainelli <florian.fainelli@broadcom.com> Link: https://lore.kernel.org/r/20240304123035.758700-7-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-05serial: 8250_bcm2835aux: Switch to use uart_read_port_properties()Andy Shevchenko1-51/+43
Since we have now a common helper to read port properties use it instead of sparse home grown solution. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com> Tested-by: Florian Fainelli <florian.fainelli@broadcom.com> Link: https://lore.kernel.org/r/20240304123035.758700-6-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-05serial: 8250_aspeed_vuart: Switch to use uart_read_port_properties()Andy Shevchenko1-35/+15
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> Reviewed-by: Andrew Jeffery <andrew@codeconstruct.com.au> Link: https://lore.kernel.org/r/20240304123035.758700-5-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-05serial: port: Introduce a common helper to read propertiesAndy Shevchenko1-0/+145
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>
2024-03-05serial: sh-sci: Call sci_serial_{in,out}() directlyGeert Uytterhoeven1-126/+119
Unlike the 8250 serial driver complex, the sh-sci driver uses only a single pair of functions to read and write serial port registers. Hence there is no need to incur the overhead of calling them through indirection, like the serial_port_{in,out}() wrappers do. Replace all calls to these wrappers by direct calls to sci_serial_{in,out}(). Remove the setup of the uart_port.serial_{in,out}() callbacks. After removal of all calls to serial_port_{in,out}() in the sh-sci driver, the only remaining user is uart_xchar_out(), which the sh-sci driver does not use. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Link: https://lore.kernel.org/r/51e79d601cb9d9d63822d3773d3cf05a96868612.1709548811.git.geert+renesas@glider.be Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-03vt: fix unicode buffer corruption when deleting charactersNicolas Pitre1-1/+1
This is the same issue that was fixed for the VGA text buffer in commit 39cdb68c64d8 ("vt: fix memory overlapping when deleting chars in the buffer"). The cure is also the same i.e. replace memcpy() with memmove() due to the overlaping buffers. Signed-off-by: Nicolas Pitre <nico@fluxnic.net> Fixes: 81732c3b2fed ("tty vt: Fix line garbage in virtual console on command line edition") Cc: stable <stable@kernel.org> Link: https://lore.kernel.org/r/sn184on2-3p0q-0qrq-0218-895349s4753o@syhkavp.arg Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-03serial: port: Don't suspend if the port is still busyYicong Yang1-1/+24
We accidently met the issue that the bash prompt is not shown after the previous command done and until the next input if there's only one CPU (In our issue other CPUs are isolated by isolcpus=). Further analysis shows it's because the port entering runtime suspend even if there's still pending chars in the buffer and the pending chars will only be processed in next device resuming. We are using amba-pl011 and the problematic flow is like below: Bash                                         kworker tty_write()   file_tty_write()     n_tty_write()       uart_write()         __uart_start()           pm_runtime_get() // wakeup waker             queue_work()                                     pm_runtime_work()                                                rpm_resume()                                                 status = RPM_RESUMING                                                 serial_port_runtime_resume()                                                   port->ops->start_tx()                                                     pl011_tx_chars()                                                       uart_write_wakeup()         […]         __uart_start()           pm_runtime_get() < 0 // because runtime status = RPM_RESUMING                                // later data are not commit to the port driver                                                 status = RPM_ACTIVE                                                 rpm_idle() -> rpm_suspend() This patch tries to fix this by checking the port busy before entering runtime suspending. A runtime_suspend callback is added for the port driver. When entering runtime suspend the callback is invoked, if there's still pending chars in the buffer then flush the buffer. Fixes: 84a9582fd203 ("serial: core: Start managing serial controllers to enable runtime PM") Cc: stable <stable@kernel.org> Reviewed-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Yicong Yang <yangyicong@hisilicon.com> Link: https://lore.kernel.org/r/20240226152351.40924-1-yangyicong@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-03serial: 8250_dw: Do not reclock if already at correct ratePeter Collingbourne1-3/+3
When userspace opens the console, we call set_termios() passing a termios with the console's configured baud rate. Currently this causes dw8250_set_termios() to disable and then re-enable the UART clock at the same frequency as it was originally. This can cause corruption of any concurrent console output. Fix it by skipping the reclocking if we are already at the correct rate. Signed-off-by: Peter Collingbourne <pcc@google.com> Fixes: 4e26b134bd17 ("serial: 8250_dw: clock rate handling for all ACPI platforms") Cc: stable@vger.kernel.org Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20240222192635.1050502-1-pcc@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-03tty: serial: imx: Fix broken RS485Rickard x Andersson1-4/+18
When about to transmit the function imx_uart_start_tx is called and in some RS485 configurations this function will call imx_uart_stop_rx. The problem is that imx_uart_stop_rx will enable loopback in order to release the RS485 bus, but when loopback is enabled transmitted data will just be looped to RX. This patch fixes the above problem by not enabling loopback when about to transmit. This driver now works well when used for RS485 half duplex master configurations. Fixes: 79d0224f6bf2 ("tty: serial: imx: Handle RS485 DE signal active high") Cc: stable <stable@kernel.org> Signed-off-by: Rickard x Andersson <rickaran@axis.com> Tested-by: Christoph Niedermaier <cniedermaier@dh-electronics.com> Link: https://lore.kernel.org/r/20240221115304.509811-1-rickaran@axis.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-03serial: pch: Use uart_prepare_sysrq_char().Sebastian Andrzej Siewior1-15/+9
The port lock is a spinlock_t which is becomes a sleeping lock on PREEMPT_RT. The driver splits the locking function into two parts: local_irq_save() and uart_port_lock() and this breaks PREEMPT_RT. Delay handling sysrq until port lock is dropped. Remove the special case in the console write routine an always use the complete locking function. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/20240301215246.891055-19-bigeasy@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-03serial: pch: Remove eg20t_port::lock.Sebastian Andrzej Siewior1-20/+6
The struct eg20t_port has a spinlock_t which is used for locking while access I/O of the device. Then there is the uart_portlock which is sometimes and nests within eg20t_port's lock. The uart_port lock is not used while using the struct in pch_uart_hal_read() which might be okay. Then both locks are used in pch_console_write() which looks odd especially the double try_lock part. All in all it looks like the uart_port's lock could replace eg20t_port's lock and simplify the code. Remove eg20t_port::lock and use uart_port's lock for the lock scope. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/20240301215246.891055-18-bigeasy@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-03serial: pch: Don't initialize uart_port's spin_lock.Sebastian Andrzej Siewior1-2/+0
There is no need to directly initialize the spinlock_t in struct uart_port. The structure is later passed to uart_add_one_port() which initialize the complete struct including the lock member. Remove spin_lock_init() on uart_port's internal lock. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/20240301215246.891055-17-bigeasy@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-03serial: pch: Don't disable interrupts while acquiring lock in ISR.Sebastian Andrzej Siewior1-3/+2
The interrupt service routine is always invoked with disabled interrupts. Remove the _irqsave() from the locking functions in the interrupts service routine/ pch_uart_interrupt(). Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/20240301215246.891055-16-bigeasy@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-03serial: pch: Make push_rx() return void.Sebastian Andrzej Siewior1-8/+4
push_rx() returns always 0. Make push_rx() return void. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/20240301215246.891055-15-bigeasy@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-03serial: pch: Invoke handle_rx_to() directly.Sebastian Andrzej Siewior1-6/+1
handle_rx() is only a wrapper around handle_rx_to() without any additional functionality. Invoke handle_rx_to() directly and remove handle_rx(). Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/20240301215246.891055-14-bigeasy@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-03serial: sifive: Use uart_prepare_sysrq_char() to handle sysrq.Sebastian Andrzej Siewior1-10/+7
The port lock is a spinlock_t which is becomes a sleeping lock on PREEMPT_RT. The driver splits the locking function into two parts: local_irq_save() and uart_port_lock() and this breaks PREEMPT_RT. Handle sysrq requests sysrq once the port lock is dropped. Remove the special case in the console write routine an always use the complete locking function. Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: linux-riscv@lists.infradead.org Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/20240301215246.891055-13-bigeasy@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-03serial: rda: Use uart_prepare_sysrq_char() to handle sysrq.Sebastian Andrzej Siewior1-18/+10
The port lock is a spinlock_t which is becomes a sleeping lock on PREEMPT_RT. The driver splits the locking function into two parts: local_irq_save() and uart_port_lock() and this breaks PREEMPT_RT. Handle sysrq requests sysrq once the port lock is dropped. Remove the special case in the console write routine an always use the complete locking function. Cc: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-unisoc@lists.infradead.org Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/20240301215246.891055-12-bigeasy@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-03serial: owl: Use uart_prepare_sysrq_char() to handle sysrq.Sebastian Andrzej Siewior1-18/+12
The port lock is a spinlock_t which is becomes a sleeping lock on PREEMPT_RT. The driver splits the locking function into two parts: local_irq_save() and uart_port_lock() and this breaks PREEMPT_RT. Handle sysrq requests sysrq once the port lock is dropped. Remove the special case in the console write routine an always use the complete locking function. Cc: Andreas Färber <afaerber@suse.de> Cc: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-actions@lists.infradead.org Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/20240301215246.891055-11-bigeasy@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-03serial: lpc32xx_hs: Use uart_prepare_sysrq_char() to handle sysrq.Sebastian Andrzej Siewior1-10/+7
The port lock is a spinlock_t which is becomes a sleeping lock on PREEMPT_RT. The driver splits the locking function into two parts: local_irq_save() and uart_port_lock() and this breaks PREEMPT_RT. Handle sysrq requests sysrq once the port lock is dropped. Remove the special case in the console write routine an always use the complete locking function. Cc: Vladimir Zapolskiy <vz@mleia.com> Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/20240301215246.891055-10-bigeasy@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-03serial: sunplus: Use uart_prepare_sysrq_char().Sebastian Andrzej Siewior1-12/+6
The port lock is a spinlock_t which is becomes a sleeping lock on PREEMPT_RT. The driver splits the locking function into two parts: local_irq_save() and uart_port_lock() and this breaks PREEMPT_RT. Delay handling sysrq until port lock is dropped. Remove the special case in the console write routine an always use the complete locking function. Cc: Hammer Hsieh <hammerh0314@gmail.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/20240301215246.891055-9-bigeasy@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-03serial: pxa: Use uart_prepare_sysrq_char().Sebastian Andrzej Siewior1-11/+6
The port lock is a spinlock_t which is becomes a sleeping lock on PREEMPT_RT. The driver splits the locking function into two parts: local_irq_save() and uart_port_lock() and this breaks PREEMPT_RT. Delay handling sysrq until port lock is dropped. Remove the special case in the console write routine an always use the complete locking function. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/20240301215246.891055-8-bigeasy@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-03serial: omap: Use uart_prepare_sysrq_char().Sebastian Andrzej Siewior1-10/+6
The port lock is a spinlock_t which is becomes a sleeping lock on PREEMPT_RT. The driver splits the locking function into two parts: local_irq_save() and uart_port_lock() and this breaks PREEMPT_RT. Delay handling sysrq until port lock is dropped. Remove the special case in the console write routine an always use the complete locking function. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/20240301215246.891055-7-bigeasy@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-03serial: msm: Use uart_prepare_sysrq_char().Sebastian Andrzej Siewior1-23/+10
The port lock is a spinlock_t which is becomes a sleeping lock on PREEMPT_RT. The driver splits the locking function into two parts: local_irq_save() and uart_port_lock() and this breaks PREEMPT_RT. Delay handling sysrq until port lock is dropped. Remove the special case in the console write routine an always use the complete locking function. Cc: Bjorn Andersson <andersson@kernel.org> Cc: Konrad Dybcio <konrad.dybcio@linaro.org> Cc: linux-arm-msm@vger.kernel.org Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/20240301215246.891055-6-bigeasy@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-03serial: meson: Use uart_prepare_sysrq_char().Sebastian Andrzej Siewior1-14/+8
The port lock is a spinlock_t which is becomes a sleeping lock on PREEMPT_RT. The driver splits the locking function into two parts: local_irq_save() and uart_port_lock() and this breaks PREEMPT_RT. Delay handling sysrq until port lock is dropped. Remove the special case in the console write routine an always use the complete locking function. Cc: Kevin Hilman <khilman@baylibre.com> Cc: Jerome Brunet <jbrunet@baylibre.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-amlogic@lists.infradead.org Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/20240301215246.891055-5-bigeasy@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>