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2023-01-21Merge tag 'tty-6.2-rc5' of ↵Linus Torvalds5-20/+44
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial driver fixes from Greg KH: "Here are some small tty and serial driver fixes for 6.2-rc5 that resolve a number of tiny reported issues and some new device ids. They include: - new device id for the exar serial driver - speakup tty driver bugfix - atmel serial driver baudrate fixup - stm32 serial driver bugfix and then revert as the bugfix broke the build. That will come back in a later pull request once it is all worked out properly. - amba-pl011 serial driver rs486 mode bugfix - qcom_geni serial driver bugfix Most of these have been in linux-next with no reported problems (well, other than the build breakage which generated the revert), the new device id passed 0-day testing" * tag 'tty-6.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: serial: exar: Add support for Sealevel 7xxxC serial cards Revert "serial: stm32: Merge hard IRQ and threaded IRQ handling into single IRQ handler" tty: serial: qcom_geni: avoid duplicate struct member init serial: atmel: fix incorrect baudrate setup tty: fix possible null-ptr-defer in spk_ttyio_release serial: stm32: Merge hard IRQ and threaded IRQ handling into single IRQ handler serial: amba-pl011: fix high priority character transmission in rs486 mode serial: pch_uart: Pass correct sg to dma_unmap_sg() tty: serial: qcom-geni-serial: fix slab-out-of-bounds on RX FIFO buffer
2023-01-20serial: exar: Add support for Sealevel 7xxxC serial cardsMatthew Howell1-0/+14
Add support for Sealevel 7xxxC serial cards. This patch: * Adds IDs to recognize 7xxxC cards from Sealevel Systems. * Updates exar_pci_probe() to set nr_ports to last two bytes of primary dev ID for these cards. Signed-off-by: Matthew Howell <matthew.howell@sealevel.com> Cc: stable <stable@kernel.org> Link: https://lore.kernel.org/r/alpine.DEB.2.21.2301191440010.22558@tstest-VirtualBox Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-20Revert "serial: stm32: Merge hard IRQ and threaded IRQ handling into single ↵Greg Kroah-Hartman1-4/+27
IRQ handler" This reverts commit f24771b62a83239f0dce816bddf0f6807f436235 as it is reported to break the build. Reported-by: kernel test robot <lkp@intel.com> Link: https://lore.kernel.org/r/202301200130.ttBiTzfO-lkp@intel.com Fixes: f24771b62a83 ("serial: stm32: Merge hard IRQ and threaded IRQ handling into single IRQ handler") Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Valentin Caron <valentin.caron@foss.st.com> # V3 Cc: Marek Vasut <marex@denx.de> Cc: Johan Hovold <johan@kernel.org> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19Merge tag 'printk-for-6.2-rc5' of ↵Linus Torvalds2-15/+10
git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux Pull printk fixes from Petr Mladek: - Prevent a potential deadlock when configuring kgdb console - Fix a kernel doc warning * tag 'printk-for-6.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux: kernel/printk/printk.c: Fix W=1 kernel-doc warning tty: serial: kgdboc: fix mutex locking order for configure_kgdboc()
2023-01-19tty: serial: qcom_geni: avoid duplicate struct member initArnd Bergmann1-6/+8
When -Woverride-init is enabled in a build, gcc points out that qcom_geni_serial_pm_ops contains conflicting initializers: drivers/tty/serial/qcom_geni_serial.c:1586:20: error: initialized field overwritten [-Werror=override-init] 1586 | .restore = qcom_geni_serial_sys_hib_resume, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/tty/serial/qcom_geni_serial.c:1586:20: note: (near initialization for 'qcom_geni_serial_pm_ops.restore') drivers/tty/serial/qcom_geni_serial.c:1587:17: error: initialized field overwritten [-Werror=override-init] 1587 | .thaw = qcom_geni_serial_sys_hib_resume, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Open-code the initializers with the version that was already used, and use the pm_sleep_ptr() method to deal with unused ones, in place of the __maybe_unused annotation. Fixes: 35781d8356a2 ("tty: serial: qcom-geni-serial: Add support for Hibernation feature") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Douglas Anderson <dianders@chromium.org> Link: https://lore.kernel.org/r/20221215165453.1864836-1-arnd@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19serial: atmel: fix incorrect baudrate setupTobias Schramm1-7/+1
Commit ba47f97a18f2 ("serial: core: remove baud_rates when serial console setup") changed uart_set_options to select the correct baudrate configuration based on the absolute error between requested baudrate and available standard baudrate settings. Prior to that commit the baudrate was selected based on which predefined standard baudrate did not exceed the requested baudrate. This change of selection logic was never reflected in the atmel serial driver. Thus the comment left in the atmel serial driver is no longer accurate. Additionally the manual rounding up described in that comment and applied via (quot - 1) requests an incorrect baudrate. Since uart_set_options uses tty_termios_encode_baud_rate to determine the appropriate baudrate flags this can cause baudrate selection to fail entirely because tty_termios_encode_baud_rate will only select a baudrate if relative error between requested and selected baudrate does not exceed +/-2%. Fix that by requesting actual, exact baudrate used by the serial. Fixes: ba47f97a18f2 ("serial: core: remove baud_rates when serial console setup") Cc: stable <stable@kernel.org> Signed-off-by: Tobias Schramm <t.schramm@manjaro.org> Acked-by: Richard Genoud <richard.genoud@gmail.com> Link: https://lore.kernel.org/r/20230109072940.202936-1-t.schramm@manjaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19Merge branch 'rework/console-list-lock' into for-linusPetr Mladek2-15/+10
2023-01-19serial: stm32: Merge hard IRQ and threaded IRQ handling into single IRQ handlerMarek Vasut1-27/+4
Requesting an interrupt with IRQF_ONESHOT will run the primary handler in the hard-IRQ context even in the force-threaded mode. The force-threaded mode is used by PREEMPT_RT in order to avoid acquiring sleeping locks (spinlock_t) in hard-IRQ context. This combination makes it impossible and leads to "sleeping while atomic" warnings. Use one interrupt handler for both handlers (primary and secondary) and drop the IRQF_ONESHOT flag which is not needed. Fixes: e359b4411c283 ("serial: stm32: fix threaded interrupt handling") Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Tested-by: Valentin Caron <valentin.caron@foss.st.com> # V3 Signed-off-by: Marek Vasut <marex@denx.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20230112180417.25595-1-marex@denx.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19serial: amba-pl011: fix high priority character transmission in rs486 modeLino Sanfilippo1-4/+4
In RS485 mode the transmission of a high priority character fails since it is written to the data register before the transmitter is enabled. Fix this in pl011_tx_chars() by enabling RS485 transmission before writing the character. Fixes: 8d479237727c ("serial: amba-pl011: add RS485 support") Cc: stable@vger.kernel.org Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Link: https://lore.kernel.org/r/20230108181735.10937-1-LinoSanfilippo@gmx.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19serial: pch_uart: Pass correct sg to dma_unmap_sg()Ilpo Järvinen1-1/+1
A local variable sg is used to store scatterlist pointer in pch_dma_tx_complete(). The for loop doing Tx byte accounting before dma_unmap_sg() alters sg in its increment statement. Therefore, the pointer passed into dma_unmap_sg() won't match to the one given to dma_map_sg(). To fix the problem, use priv->sg_tx_p directly in dma_unmap_sg() instead of the local variable. Fixes: da3564ee027e ("pch_uart: add multi-scatter processing") Cc: stable@vger.kernel.org Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20230103093435.4396-1-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19tty: serial: qcom-geni-serial: fix slab-out-of-bounds on RX FIFO bufferKrzysztof Kozlowski1-2/+16
Driver's probe allocates memory for RX FIFO (port->rx_fifo) based on default RX FIFO depth, e.g. 16. Later during serial startup the qcom_geni_serial_port_setup() updates the RX FIFO depth (port->rx_fifo_depth) to match real device capabilities, e.g. to 32. The RX UART handle code will read "port->rx_fifo_depth" number of words into "port->rx_fifo" buffer, thus exceeding the bounds. This can be observed in certain configurations with Qualcomm Bluetooth HCI UART device and KASAN: Bluetooth: hci0: QCA Product ID :0x00000010 Bluetooth: hci0: QCA SOC Version :0x400a0200 Bluetooth: hci0: QCA ROM Version :0x00000200 Bluetooth: hci0: QCA Patch Version:0x00000d2b Bluetooth: hci0: QCA controller version 0x02000200 Bluetooth: hci0: QCA Downloading qca/htbtfw20.tlv bluetooth hci0: Direct firmware load for qca/htbtfw20.tlv failed with error -2 Bluetooth: hci0: QCA Failed to request file: qca/htbtfw20.tlv (-2) Bluetooth: hci0: QCA Failed to download patch (-2) ================================================================== BUG: KASAN: slab-out-of-bounds in handle_rx_uart+0xa8/0x18c Write of size 4 at addr ffff279347d578c0 by task swapper/0/0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.1.0-rt5-00350-gb2450b7e00be-dirty #26 Hardware name: Qualcomm Technologies, Inc. Robotics RB5 (DT) Call trace: dump_backtrace.part.0+0xe0/0xf0 show_stack+0x18/0x40 dump_stack_lvl+0x8c/0xb8 print_report+0x188/0x488 kasan_report+0xb4/0x100 __asan_store4+0x80/0xa4 handle_rx_uart+0xa8/0x18c qcom_geni_serial_handle_rx+0x84/0x9c qcom_geni_serial_isr+0x24c/0x760 __handle_irq_event_percpu+0x108/0x500 handle_irq_event+0x6c/0x110 handle_fasteoi_irq+0x138/0x2cc generic_handle_domain_irq+0x48/0x64 If the RX FIFO depth changes after probe, be sure to resize the buffer. Fixes: f9d690b6ece7 ("tty: serial: qcom_geni_serial: Allocate port->rx_fifo buffer in probe") Cc: <stable@vger.kernel.org> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20221221164022.1087814-1-krzysztof.kozlowski@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-16tty: serial: kgdboc: fix mutex locking order for configure_kgdboc()John Ogness2-15/+10
Several mutexes are taken while setting up console serial ports. In particular, the tty_port->mutex and @console_mutex are taken: serial_pnp_probe serial8250_register_8250_port uart_add_one_port (locks tty_port->mutex) uart_configure_port register_console (locks @console_mutex) In order to synchronize kgdb's tty_find_polling_driver() with register_console(), commit 6193bc90849a ("tty: serial: kgdboc: synchronize tty_find_polling_driver() and register_console()") takes the @console_mutex. However, this leads to the following call chain (with locking): platform_probe kgdboc_probe configure_kgdboc (locks @console_mutex) tty_find_polling_driver uart_poll_init (locks tty_port->mutex) uart_set_options This is clearly deadlock potential due to the reverse lock ordering. Since uart_set_options() requires holding @console_mutex in order to serialize early initialization of the serial-console lock, take the @console_mutex in uart_poll_init() instead of configure_kgdboc(). Since configure_kgdboc() was using @console_mutex for safe traversal of the console list, change it to use the SRCU iterator instead. Add comments to uart_set_options() kerneldoc mentioning that it requires holding @console_mutex (aka the console_list_lock). Fixes: 6193bc90849a ("tty: serial: kgdboc: synchronize tty_find_polling_driver() and register_console()") Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Reviewed-by: Petr Mladek <pmladek@suse.com> [pmladek@suse.com: Export console_srcu_read_lock_is_held() to fix build kgdboc as a module.] Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20230112161213.1434854-1-john.ogness@linutronix.de
2023-01-13Merge tag 'for-linus-6.2-rc4-tag' of ↵Linus Torvalds1-19/+31
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: - two cleanup patches - a fix of a memory leak in the Xen pvfront driver - a fix of a locking issue in the Xen hypervisor console driver * tag 'for-linus-6.2-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/pvcalls: free active map buffer on pvcalls_front_free_map hvc/xen: lock console list traversal x86/xen: Remove the unused function p2m_index() xen: make remove callback of xen driver void returned
2023-01-09hvc/xen: lock console list traversalRoger Pau Monne1-17/+29
The currently lockless access to the xen console list in vtermno_to_xencons() is incorrect, as additions and removals from the list can happen anytime, and as such the traversal of the list to get the private console data for a given termno needs to happen with the lock held. Note users that modify the list already do so with the lock taken. Adjust current lock takers to use the _irq{save,restore} helpers, since the context in which vtermno_to_xencons() is called can have interrupts disabled. Use the _irq{save,restore} set of helpers to switch the current callers to disable interrupts in the locked region. I haven't checked if existing users could instead use the _irq variant, as I think it's safer to use _irq{save,restore} upfront. While there switch from using list_for_each_entry_safe to list_for_each_entry: the current entry cursor won't be removed as part of the code in the loop body, so using the _safe variant is pointless. Fixes: 02e19f9c7cac ('hvc_xen: implement multiconsole support') Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Link: https://lore.kernel.org/r/20221130163611.14686-1-roger.pau@citrix.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-12-26treewide: Convert del_timer*() to timer_shutdown*()Steven Rostedt (Google)2-2/+2
Due to several bugs caused by timers being re-armed after they are shutdown and just before they are freed, a new state of timers was added called "shutdown". After a timer is set to this state, then it can no longer be re-armed. The following script was run to find all the trivial locations where del_timer() or del_timer_sync() is called in the same function that the object holding the timer is freed. It also ignores any locations where the timer->function is modified between the del_timer*() and the free(), as that is not considered a "trivial" case. This was created by using a coccinelle script and the following commands: $ cat timer.cocci @@ expression ptr, slab; identifier timer, rfield; @@ ( - del_timer(&ptr->timer); + timer_shutdown(&ptr->timer); | - del_timer_sync(&ptr->timer); + timer_shutdown_sync(&ptr->timer); ) ... when strict when != ptr->timer ( kfree_rcu(ptr, rfield); | kmem_cache_free(slab, ptr); | kfree(ptr); ) $ spatch timer.cocci . > /tmp/t.patch $ patch -p1 < /tmp/t.patch Link: https://lore.kernel.org/lkml/20221123201306.823305113@linutronix.de/ Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Pavel Machek <pavel@ucw.cz> [ LED ] Acked-by: Kalle Valo <kvalo@kernel.org> [ wireless ] Acked-by: Paolo Abeni <pabeni@redhat.com> [ networking ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-12-16Merge tag 'driver-core-6.2-rc1' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the set of driver core and kernfs changes for 6.2-rc1. The "big" change in here is the addition of a new macro, container_of_const() that will preserve the "const-ness" of a pointer passed into it. The "problem" of the current container_of() macro is that if you pass in a "const *", out of it can comes a non-const pointer unless you specifically ask for it. For many usages, we want to preserve the "const" attribute by using the same call. For a specific example, this series changes the kobj_to_dev() macro to use it, allowing it to be used no matter what the const value is. This prevents every subsystem from having to declare 2 different individual macros (i.e. kobj_const_to_dev() and kobj_to_dev()) and having the compiler enforce the const value at build time, which having 2 macros would not do either. The driver for all of this have been discussions with the Rust kernel developers as to how to properly mark driver core, and kobject, objects as being "non-mutable". The changes to the kobject and driver core in this pull request are the result of that, as there are lots of paths where kobjects and device pointers are not modified at all, so marking them as "const" allows the compiler to enforce this. So, a nice side affect of the Rust development effort has been already to clean up the driver core code to be more obvious about object rules. All of this has been bike-shedded in quite a lot of detail on lkml with different names and implementations resulting in the tiny version we have in here, much better than my original proposal. Lots of subsystem maintainers have acked the changes as well. Other than this change, included in here are smaller stuff like: - kernfs fixes and updates to handle lock contention better - vmlinux.lds.h fixes and updates - sysfs and debugfs documentation updates - device property updates All of these have been in the linux-next tree for quite a while with no problems" * tag 'driver-core-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (58 commits) device property: Fix documentation for fwnode_get_next_parent() firmware_loader: fix up to_fw_sysfs() to preserve const usb.h: take advantage of container_of_const() device.h: move kobj_to_dev() to use container_of_const() container_of: add container_of_const() that preserves const-ness of the pointer driver core: fix up missed drivers/s390/char/hmcdrv_dev.c class.devnode() conversion. driver core: fix up missed scsi/cxlflash class.devnode() conversion. driver core: fix up some missing class.devnode() conversions. driver core: make struct class.devnode() take a const * driver core: make struct class.dev_uevent() take a const * cacheinfo: Remove of_node_put() for fw_token device property: Add a blank line in Kconfig of tests device property: Rename goto label to be more precise device property: Move PROPERTY_ENTRY_BOOL() a bit down device property: Get rid of __PROPERTY_ENTRY_ARRAY_EL*SIZE*() kernfs: fix all kernel-doc warnings and multiple typos driver core: pass a const * into of_device_uevent() kobject: kset_uevent_ops: make name() callback take a const * kobject: kset_uevent_ops: make filter() callback take a const * kobject: make kobject_namespace take a const * ...
2022-12-16Merge tag 'tty-6.2-rc1' of ↵Linus Torvalds82-1183/+1286
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 changes for 6.2-rc1. As in previous kernel releases, nothing big here at all, just some small incremental serial/tty layer cleanups and some individual driver additions and fixes. Highlights are: - serial helper macros from Jiri Slaby to reduce the amount of duplicated code in serial drivers - api cleanups and consolidations from Ilpo Järvinen in lots of serial drivers - the usual set of n_gsm fixes from Daniel Starke as that code gets exercised more - TIOCSTI is finally able to be disabled if requested (security hardening feature from Kees Cook) - fsl_lpuart driver fixes and features added - other small serial driver additions and fixes All of these have been in linux-next for a while with no reported problems" * tag 'tty-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (97 commits) serial: atmel: don't stop the transmitter when doing PIO serial: atmel: cleanup atmel_start+stop_tx() tty: serial: fsl_lpuart: switch to new dmaengine_terminate_* API serial: sunsab: Fix error handling in sunsab_init() serial: altera_uart: fix locking in polling mode serial: pch: Fix PCI device refcount leak in pch_request_dma() tty: serial: fsl_lpuart: Use pm_ptr() to avoid need to make pm __maybe_unused tty: serial: fsl_lpuart: Add runtime pm support tty: serial: fsl_lpuart: enable wakeup source for lpuart serdev: Replace poll loop by readx_poll_timeout() macro tty: synclink_gt: unwind actions in error path of net device open serial: stm32: move dma_request_chan() before clk_prepare_enable() dt-bindings: serial: xlnx,opb-uartlite: Drop 'contains' from 'xlnx,use-parity' serial: pl011: Do not clear RX FIFO & RX interrupt in unthrottle. serial: amba-pl011: avoid SBSA UART accessing DMACR register tty: serial: altera_jtaguart: remove struct altera_jtaguart tty: serial: altera_jtaguart: use uart_port::read_status_mask tty: serial: altera_jtaguart: remove unused altera_jtaguart::sigs tty: serial: altera_jtaguart: remove flag from altera_jtaguart_rx_chars() n_tty: Rename tail to old_tail in n_tty_read() ...
2022-12-15xen: make remove callback of xen driver void returnedDawei Li1-2/+2
Since 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 xen bus based drivers. Acked-by: Juergen Gross <jgross@suse.com> Signed-off-by: Dawei Li <set_pte_at@outlook.com> Link: https://lore.kernel.org/r/TYCP286MB23238119AB4DF190997075C9CAE39@TYCP286MB2323.JPNP286.PROD.OUTLOOK.COM Signed-off-by: Juergen Gross <jgross@suse.com>
2022-12-12Merge tag 'printk-for-6.2' of ↵Linus Torvalds10-26/+90
git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux Pull printk updates from Petr Mladek: - Add NMI-safe SRCU reader API. It uses atomic_inc() instead of this_cpu_inc() on strong load-store architectures. - Introduce new console_list_lock to synchronize a manipulation of the list of registered consoles and their flags. This is a first step in removing the big-kernel-lock-like behavior of console_lock(). This semaphore still serializes console->write() calbacks against: - each other. It primary prevents potential races between early and proper console drivers using the same device. - suspend()/resume() callbacks and init() operations in some drivers. - various other operations in the tty/vt and framebufer susbsystems. It is likely that console_lock() serializes even operations that are not directly conflicting with the console->write() callbacks here. This is the most complicated big-kernel-lock aspect of the console_lock() that will be hard to untangle. - Introduce new console_srcu lock that is used to safely iterate and access the registered console drivers under SRCU read lock. This is a prerequisite for introducing atomic console drivers and console kthreads. It will reduce the complexity of serialization against normal consoles and console_lock(). Also it should remove the risk of deadlock during critical situations, like Oops or panic, when only atomic consoles are registered. - Check whether the console is registered instead of enabled on many locations. It was a historical leftover. - Cleanly force a preferred console in xenfb code instead of a dirty hack. - A lot of code and comment clean ups and improvements. * tag 'printk-for-6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux: (47 commits) printk: htmldocs: add missing description tty: serial: sh-sci: use setup() callback for early console printk: relieve console_lock of list synchronization duties tty: serial: kgdboc: use console_list_lock to trap exit tty: serial: kgdboc: synchronize tty_find_polling_driver() and register_console() tty: serial: kgdboc: use console_list_lock for list traversal tty: serial: kgdboc: use srcu console list iterator proc: consoles: use console_list_lock for list iteration tty: tty_io: use console_list_lock for list synchronization printk, xen: fbfront: create/use safe function for forcing preferred netconsole: avoid CON_ENABLED misuse to track registration usb: early: xhci-dbc: use console_is_registered() tty: serial: xilinx_uartps: use console_is_registered() tty: serial: samsung_tty: use console_is_registered() tty: serial: pic32_uart: use console_is_registered() tty: serial: earlycon: use console_is_registered() tty: hvc: use console_is_registered() efi: earlycon: use console_is_registered() tty: nfcon: use console_is_registered() serial_core: replace uart_console_enabled() with uart_console_registered() ...
2022-12-02tty: serial: sh-sci: use setup() callback for early consoleJohn Ogness1-4/+16
When setting up the early console, the setup() callback of the regular console is used. It is called manually before registering the early console instead of providing a setup() callback for the early console. This is probably because the early setup needs a different @options during the early stage. The issue here is that the setup() callback is called without the console_list_lock held and functions such as uart_set_options() expect that. Rather than manually calling the setup() function before registering, provide an early console setup() callback that will use the different early options. This ensures that the error checking, ordering, and locking context when setting up the early console are correct. Since this early console can only be registered via the earlyprintk= parameter, the @options argument of the setup() callback will always be NULL. Rather than simply ignoring the argument, add a WARN_ON() to get our attention in case the setup() callback semantics should change in the future. Note that technically the current implementation works because it is only used in early boot. And since the early console setup is performed before registering, it cannot race with anything and thus does not need any locking. However, longterm maintenance is easier when drivers rely on the subsystem API rather than manually implementing steps that could cause breakage in the future. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20221116162152.193147-41-john.ogness@linutronix.de
2022-12-02tty: serial: kgdboc: use console_list_lock to trap exitJohn Ogness1-3/+3
kgdboc_earlycon_init() uses the console_lock to ensure that no consoles are unregistered until the kgdboc_earlycon is setup. The console_list_lock should be used instead because list synchronization responsibility will be removed from the console_lock in a later change. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20221116162152.193147-39-john.ogness@linutronix.de
2022-12-02tty: serial: kgdboc: synchronize tty_find_polling_driver() and ↵John Ogness1-4/+12
register_console() Calling tty_find_polling_driver() can lead to uart_set_options() being called (via the poll_init() callback of tty_operations) to configure the uart. But uart_set_options() can also be called by register_console() (via the setup() callback of console). Take the console_list_lock to synchronize against register_console() and also use it for console list traversal. This also ensures the console list cannot change until the polling console has been chosen. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Douglas Anderson <dianders@chromium.org> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20221116162152.193147-38-john.ogness@linutronix.de
2022-12-02tty: serial: kgdboc: use console_list_lock for list traversalJohn Ogness1-0/+12
configure_kgdboc() uses the console_lock for console list iteration. Use the console_list_lock instead because list synchronization responsibility will be removed from the console_lock in a later change. The SRCU iterator could have been used here, but a later change will relocate the locking of the console_list_lock to also provide synchronization against register_console(). Note, the console_lock is still needed to serialize the device() callback with other console operations. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Douglas Anderson <dianders@chromium.org> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20221116162152.193147-37-john.ogness@linutronix.de
2022-12-02tty: serial: kgdboc: use srcu console list iteratorJohn Ogness1-2/+8
Use srcu console list iteration for safe console list traversal. Note that this is a preparatory change for when console_lock no longer provides synchronization for the console list. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Douglas Anderson <dianders@chromium.org> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20221116162152.193147-36-john.ogness@linutronix.de
2022-12-02tty: tty_io: use console_list_lock for list synchronizationJohn Ogness1-6/+12
show_cons_active() uses the console_lock to gather information on registered consoles. It requires that no consoles are unregistered until it is finished. The console_list_lock should be used because list synchronization responsibility will be removed from the console_lock in a later change. Note, the console_lock is still needed to serialize the device() callback with other console operations. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20221116162152.193147-34-john.ogness@linutronix.de
2022-12-02tty: serial: xilinx_uartps: use console_is_registered()John Ogness1-1/+1
It is not reliable to check for CON_ENABLED in order to identify if a console is registered. Use console_is_registered() instead. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20221116162152.193147-30-john.ogness@linutronix.de
2022-12-02tty: serial: samsung_tty: use console_is_registered()John Ogness1-1/+1
It is not reliable to check for CON_ENABLED in order to identify if a console is registered. Use console_is_registered() instead. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20221116162152.193147-29-john.ogness@linutronix.de
2022-12-02tty: serial: pic32_uart: use console_is_registered()John Ogness1-1/+1
It is not reliable to check for CON_ENABLED in order to identify if a console is registered. Use console_is_registered() instead. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20221116162152.193147-28-john.ogness@linutronix.de
2022-12-02tty: serial: earlycon: use console_is_registered()John Ogness1-2/+2
It is not reliable to check for CON_ENABLED in order to identify if a console is registered. Use console_is_registered() instead. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20221116162152.193147-27-john.ogness@linutronix.de
2022-12-02tty: hvc: use console_is_registered()John Ogness1-2/+2
It is not reliable to check for CON_ENABLED in order to identify if a console is registered. Use console_is_registered() instead. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20221116162152.193147-26-john.ogness@linutronix.de
2022-12-02serial_core: replace uart_console_enabled() with uart_console_registered()John Ogness3-9/+9
All users of uart_console_enabled() really want to know if a console is registered. It is not reliable to check for CON_ENABLED in order to identify if a console is registered. Use console_is_registered() instead. A _locked() variant is provided because uart_set_options() is always called with the console_list_lock held and must check if a console is registered in order to synchronize with kgdboc. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20221116162152.193147-23-john.ogness@linutronix.de
2022-12-02tty: tty_io: document console_lock usageJohn Ogness1-0/+10
show_cons_active() uses the console_lock to gather information on registered consoles. Since the console_lock is being used for multiple reasons, explicitly document these reasons. This will be useful when the console_lock is split into fine-grained locking. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20221116162152.193147-10-john.ogness@linutronix.de
2022-12-02tty: serial: kgdboc: document console_lock usageJohn Ogness1-0/+8
kgdboc_earlycon_init() uses the console_lock to ensure that no consoles are unregistered until the kgdboc_earlycon is setup. This is necessary because the trapping of the exit() callback assumes that the exit() callback is not called before the trap is setup. Explicitly document this non-typical console_lock usage. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20221116162152.193147-9-john.ogness@linutronix.de
2022-12-02serial: kgdboc: Lock console list in probe functionThomas Gleixner1-0/+2
Unprotected list walks are not necessarily safe. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20221116162152.193147-2-john.ogness@linutronix.de
2022-11-24driver core: make struct class.devnode() take a const *Greg Kroah-Hartman1-1/+1
The devnode() in struct class should not be modifying the device that is passed into it, so mark it as a const * and propagate the function signature changes out into all relevant subsystems that use this callback. Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Reinette Chatre <reinette.chatre@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: x86@kernel.org Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: Jens Axboe <axboe@kernel.dk> Cc: Justin Sanders <justin@coraid.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Benjamin Gaignard <benjamin.gaignard@collabora.com> Cc: Liam Mark <lmark@codeaurora.org> Cc: Laura Abbott <labbott@redhat.com> Cc: Brian Starkey <Brian.Starkey@arm.com> Cc: John Stultz <jstultz@google.com> Cc: "Christian König" <christian.koenig@amd.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Maxime Ripard <mripard@kernel.org> Cc: Thomas Zimmermann <tzimmermann@suse.de> Cc: David Airlie <airlied@gmail.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Leon Romanovsky <leon@kernel.org> Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Sean Young <sean@mess.org> Cc: Frank Haverkamp <haver@linux.ibm.com> Cc: Jiri Slaby <jirislaby@kernel.org> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Cornelia Huck <cohuck@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Jaroslav Kysela <perex@perex.cz> Cc: Takashi Iwai <tiwai@suse.com> Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl> Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Cc: Xie Yongji <xieyongji@bytedance.com> Cc: Gautam Dawar <gautam.dawar@xilinx.com> Cc: Dan Carpenter <error27@gmail.com> Cc: Eli Cohen <elic@nvidia.com> Cc: Parav Pandit <parav@nvidia.com> Cc: Maxime Coquelin <maxime.coquelin@redhat.com> Cc: alsa-devel@alsa-project.org Cc: dri-devel@lists.freedesktop.org Cc: kvm@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org Cc: linux-block@vger.kernel.org Cc: linux-input@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: linux-rdma@vger.kernel.org Cc: linux-scsi@vger.kernel.org Cc: linux-usb@vger.kernel.org Cc: virtualization@lists.linux-foundation.org Link: https://lore.kernel.org/r/20221123122523.1332370-2-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-23serial: atmel: don't stop the transmitter when doing PIOJiri Slaby (SUSE)1-10/+15
Writing ATMEL_US_TXDIS to ATMEL_US_CR makes the transmitter NOT to send the just queued character. This means when the character is last and uart calls ops->stop_tx(), the character is not sent at all. The usart datasheet is not much specific on this, it just says the transmitter is stopped. But apparently, the character is dropped. So we should stop the transmitter only for DMA and PDC transfers to not send any more characters. For PIO, this is unexpected and deviates from other drivers. In particular, the below referenced commit broke TX as it added a call to ->stop_tx() after the very last character written to the transmitter. So fix this by limiting the write of ATMEL_US_TXDIS to DMA transfers only. Even there, I don't know if it is correctly implemented. Are all the queued characters sent once ->start_tx() is called? Anyone tested flow control -- be it hard (RTSCTS) or the soft (XOFF/XON) one? Fixes: 2d141e683e9a ("tty: serial: use uart_port_tx() helper") Cc: Richard Genoud <richard.genoud@gmail.com> Cc: Nicolas Ferre <nicolas.ferre@microchip.com> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Claudiu Beznea <claudiu.beznea@microchip.com> Cc: linux-arm-kernel@lists.infradead.org Reported-by: Michael Walle <michael@walle.cc> Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20221123082736.24566-2-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-23serial: atmel: cleanup atmel_start+stop_tx()Jiri Slaby (SUSE)1-7/+9
Define local variables holding information about whether pdc or dma is used in the HW. These are retested several times by calls to atmel_use_pdc_tx() and atmel_use_dma_tx(). So to make the code more readable, simply cache the values. This is also a preparatory patch for the next one (where is_pdc is used once more in atmel_stop_tx()). Cc: Richard Genoud <richard.genoud@gmail.com> Cc: Nicolas Ferre <nicolas.ferre@microchip.com> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Claudiu Beznea <claudiu.beznea@microchip.com> Cc: linux-arm-kernel@lists.infradead.org Reported-by: Michael Walle <michael@walle.cc> Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20221123082736.24566-1-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-23tty: serial: fsl_lpuart: switch to new dmaengine_terminate_* APISherry Sun1-4/+4
Convert dmaengine_terminate_all() calls to synchronous and asynchronous versions where appropriate. Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20221123023619.30173-1-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-23serial: sunsab: Fix error handling in sunsab_init()Yuan Can1-1/+7
The sunsab_init() returns the platform_driver_register() directly without checking its return value, if platform_driver_register() failed, the allocated sunsab_ports is leaked. Fix by free sunsab_ports and set it to NULL when platform_driver_register() failed. Fixes: c4d37215a824 ("[SERIAL] sunsab: Convert to of_driver framework.") Signed-off-by: Yuan Can <yuancan@huawei.com> Link: https://lore.kernel.org/r/20221123061212.52593-1-yuancan@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-23serial: altera_uart: fix locking in polling modeGabriel Somlo1-2/+3
Since altera_uart_interrupt() may also be called from a poll timer in "serving_softirq" context, use spin_[lock_irqsave|unlock_irqrestore] variants, which are appropriate for both softirq and hardware interrupt contexts. Fixes: 2f8b9c15cd88 ("altera_uart: Add support for polling mode (IRQ-less)") Signed-off-by: Gabriel Somlo <gsomlo@gmail.com> Link: https://lore.kernel.org/r/20221122200426.888349-1-gsomlo@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-22serial: pch: Fix PCI device refcount leak in pch_request_dma()Xiongfeng Wang1-0/+4
As comment of pci_get_slot() says, it returns a pci_device with its refcount increased. The caller must decrement the reference count by calling pci_dev_put(). Since 'dma_dev' is only used to filter the channel in filter(), we can call pci_dev_put() before exiting from pch_request_dma(). Add the missing pci_dev_put() for the normal and error path. Fixes: 3c6a483275f4 ("Serial: EG20T: add PCH_UART driver") Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> Link: https://lore.kernel.org/r/20221122114559.27692-1-wangxiongfeng2@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-22tty: serial: fsl_lpuart: Use pm_ptr() to avoid need to make pm __maybe_unusedSherry Sun1-10/+10
Use pm_ptr() to remove the need to mark the pm functions as __maybe_unused when the kernel is built without CONFIG_PM support. Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20221110113859.8485-4-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-22tty: serial: fsl_lpuart: Add runtime pm supportSherry Sun1-0/+60
Add runtime pm support to manage the lpuart clock. Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20221110113859.8485-3-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-22tty: serial: fsl_lpuart: enable wakeup source for lpuartSherry Sun1-81/+200
LPUART supports both synchronous wakeup and asynchronous wakeup(wakeup the system when the UART clocks are shut-off), the synchronous wakeup is configured by UARTCTRL_RIE interrupt, and the asynchronous wakeup is configured by UARTBAUD_RXEDGIE interrupt. Add lpuart_uport_is_active() to determine if the uart port needs to get into the suspend states, also add lpuart_suspend_noirq() and lpuart_resume_noirq() to enable and disable the wakeup irq bits if the uart port needs to be set as wakeup source. When use lpuart with DMA mode, it still needs to switch to the cpu mode in .suspend() that enable cpu interrupts RIE and RXEDGIE as wakeup source, after system resume back, needs to setup DMA again, .resume() will share the HW setup code with .startup(), so abstract the same code to the api like lpuart32_hw_setup(). Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20221110113859.8485-2-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-22tty: synclink_gt: unwind actions in error path of net device openPaul Fulghum1-9/+10
Resent again, last attempt still altered the plain text. Zhengchao Shao <shaozhengchao@huawei.com> identified by inspection bugs in the error path of hdlcdev_open() in synclink_gt.c The function did not fully unwind actions in the error path. The use of try_module_get()/module_put() is unnecessary, potentially hazardous and is removed. The synclink_gt driver is already pinned any point the net device is registered, a requirement for calling this entry point. The call hdlc_open() to init the generic HDLC layer is moved to after driver level init/checks and proper rollback of previous actions is added. This is a more sensible ordering as the most common error paths are at the driver level and the driver level rollbacks require less processing than hdlc_open()/hdlc_close(). This has been tested with supported hardware. Signed-off-by:Paul Fulghum <paulkf@microgate.com> Link: https://lore.kernel.org/r/7599F007-8985-4469-BE00-52BD1530210E@microgate.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-22serial: stm32: move dma_request_chan() before clk_prepare_enable()Valentin Caron1-24/+23
If dma_request_chan() returns a PROBE_DEFER error, clk_disable_unprepare() will be called and USART clock will be disabled. But early console can be still active on the same USART. While moving dma_request_chan() before clk_prepare_enable(), the clock won't be taken in case of a DMA PROBE_DEFER error, and so it doesn't need to be disabled. Then USART is still clocked for early console. Fixes: a7770a4bfcf4 ("serial: stm32: defer probe for dma devices") Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Valentin Caron <valentin.caron@foss.st.com> Link: https://lore.kernel.org/r/20221118170602.1057863-1-valentin.caron@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-22serial: pl011: Do not clear RX FIFO & RX interrupt in unthrottle.delisun1-1/+10
Clearing the RX FIFO will cause data loss. Copy the pl011_enabl_interrupts implementation, and remove the clear interrupt and FIFO part of the code. Fixes: 211565b10099 ("serial: pl011: UPSTAT_AUTORTS requires .throttle/unthrottle") Signed-off-by: delisun <delisun@pateo.com.cn> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20221110020108.7700-1-delisun@pateo.com.cn Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-22serial: amba-pl011: avoid SBSA UART accessing DMACR registerJiamei Xie1-0/+3
Chapter "B Generic UART" in "ARM Server Base System Architecture" [1] documentation describes a generic UART interface. Such generic UART does not support DMA. In current code, sbsa_uart_pops and amba_pl011_pops share the same stop_rx operation, which will invoke pl011_dma_rx_stop, leading to an access of the DMACR register. This commit adds a using_rx_dma check in pl011_dma_rx_stop to avoid the access to DMACR register for SBSA UARTs which does not support DMA. When the kernel enables DMA engine with "CONFIG_DMA_ENGINE=y", Linux SBSA PL011 driver will access PL011 DMACR register in some functions. For most real SBSA Pl011 hardware implementations, the DMACR write behaviour will be ignored. So these DMACR operations will not cause obvious problems. But for some virtual SBSA PL011 hardware, like Xen virtual SBSA PL011 (vpl011) device, the behaviour might be different. Xen vpl011 emulation will inject a data abort to guest, when guest is accessing an unimplemented UART register. As Xen VPL011 is SBSA compatible, it will not implement DMACR register. So when Linux SBSA PL011 driver access DMACR register, it will get an unhandled data abort fault and the application will get a segmentation fault: Unhandled fault at 0xffffffc00944d048 Mem abort info: ESR = 0x96000000 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x00: ttbr address size fault Data abort info: ISV = 0, ISS = 0x00000000 CM = 0, WnR = 0 swapper pgtable: 4k pages, 39-bit VAs, pgdp=0000000020e2e000 [ffffffc00944d048] pgd=100000003ffff803, p4d=100000003ffff803, pud=100000003ffff803, pmd=100000003fffa803, pte=006800009c090f13 Internal error: ttbr address size fault: 96000000 [#1] PREEMPT SMP ... Call trace: pl011_stop_rx+0x70/0x80 tty_port_shutdown+0x7c/0xb4 tty_port_close+0x60/0xcc uart_close+0x34/0x8c tty_release+0x144/0x4c0 __fput+0x78/0x220 ____fput+0x1c/0x30 task_work_run+0x88/0xc0 do_notify_resume+0x8d0/0x123c el0_svc+0xa8/0xc0 el0t_64_sync_handler+0xa4/0x130 el0t_64_sync+0x1a0/0x1a4 Code: b9000083 b901f001 794038a0 8b000042 (b9000041) ---[ end trace 83dd93df15c3216f ]--- note: bootlogd[132] exited with preempt_count 1 /etc/rcS.d/S07bootlogd: line 47: 132 Segmentation fault start-stop-daemon This has been discussed in the Xen community, and we think it should fix this in Linux. See [2] for more information. [1] https://developer.arm.com/documentation/den0094/c/?lang=en [2] https://lists.xenproject.org/archives/html/xen-devel/2022-11/msg00543.html Fixes: 0dd1e247fd39 (drivers: PL011: add support for the ARM SBSA generic UART) Signed-off-by: Jiamei Xie <jiamei.xie@arm.com> Reviewed-by: Andre Przywara <andre.przywara@arm.com> Link: https://lore.kernel.org/r/20221117103237.86856-1-jiamei.xie@arm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-22tty: serial: altera_jtaguart: remove struct altera_jtaguartJiri Slaby (SUSE)1-20/+9
It contains only struct uart_port, so no need for another structure. Remove it and convert the rest to use struct uart_port directly. Cc: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Reviewed-by: Tobias Klauser <tklauser@distanz.ch> Link: https://lore.kernel.org/r/20221115071724.5185-4-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-22tty: serial: altera_jtaguart: use uart_port::read_status_maskJiri Slaby (SUSE)1-25/+16
Instead of self-defined struct altera_jtaguart::imr, use preexisting uart_port::read_status_mask. Note that imr was ulong. But there is no reason for that, its values are uints. And readl/writel's are used to read it/write to it. Cc: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Reviewed-by: Tobias Klauser <tklauser@distanz.ch> Link: https://lore.kernel.org/r/20221115071724.5185-3-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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