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2021-07-05Merge tag 'tty-5.14-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty / serial updates from Greg KH: "Here is the big set of tty and serial driver patches for 5.14-rc1. A bit more than normal, but nothing major, lots of cleanups. Highlights are: - lots of tty api cleanups and mxser driver cleanups from Jiri - build warning fixes - various serial driver updates - coding style cleanups - various tty driver minor fixes and updates - removal of broken and disable r3964 line discipline (finally!) All of these have been in linux-next for a while with no reported issues" * tag 'tty-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (227 commits) serial: mvebu-uart: remove unused member nb from struct mvebu_uart arm64: dts: marvell: armada-37xx: Fix reg for standard variant of UART dt-bindings: mvebu-uart: fix documentation serial: mvebu-uart: correctly calculate minimal possible baudrate serial: mvebu-uart: do not allow changing baudrate when uartclk is not available serial: mvebu-uart: fix calculation of clock divisor tty: make linux/tty_flip.h self-contained serial: Prefer unsigned int to bare use of unsigned serial: 8250: 8250_omap: Fix possible interrupt storm on K3 SoCs serial: qcom_geni_serial: use DT aliases according to DT bindings Revert "tty: serial: Add UART driver for Cortina-Access platform" tty: serial: Add UART driver for Cortina-Access platform MAINTAINERS: add me back as mxser maintainer mxser: Documentation, fix typos mxser: Documentation, make the docs up-to-date mxser: Documentation, remove traces of callout device mxser: introduce mxser_16550A_or_MUST helper mxser: rename flags to old_speed in mxser_set_serial_info mxser: use port variable in mxser_set_serial_info mxser: access info->MCR under info->slock ...
2021-07-04Merge tag 's390-5.14-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Vasily Gorbik: - Rework inline asm to get rid of error prone "register asm" constructs, which are problematic especially when code instrumentation is enabled. In particular introduce and use register pair union to allocate even/odd register pairs. Unfortunately this breaks compatibility with older clang compilers and minimum clang version for s390 has been raised to 13. https://lore.kernel.org/linux-next/CAK7LNARuSmPCEy-ak0erPrPTgZdGVypBROFhtw+=3spoGoYsyw@mail.gmail.com/ - Fix gcc 11 warnings, which triggered various minor reworks all over the code. - Add zstd kernel image compression support. - Rework boot CPU lowcore handling. - De-duplicate and move kernel memory layout setup logic earlier. - Few fixes in preparation for FORTIFY_SOURCE performing compile-time and run-time field bounds checking for mem functions. - Remove broken and unused power management support leftovers in s390 drivers. - Disable stack-protector for decompressor and purgatory to fix buildroot build. - Fix vt220 sclp console name to match the char device name. - Enable HAVE_IOREMAP_PROT and add zpci_set_irq()/zpci_clear_irq() in zPCI code. - Remove some implausible WARN_ON_ONCEs and remove arch specific counter transaction call backs in favour of default transaction handling in perf code. - Extend/add new uevents for online/config/mode state changes of AP card / queue device in zcrypt. - Minor entry and ccwgroup code improvements. - Other small various fixes and improvements all over the code. * tag 's390-5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (91 commits) s390/dasd: use register pair instead of register asm s390/qdio: get rid of register asm s390/ioasm: use symbolic names for asm operands s390/ioasm: get rid of register asm s390/cmf: get rid of register asm s390/lib,string: get rid of register asm s390/lib,uaccess: get rid of register asm s390/string: get rid of register asm s390/cmpxchg: use register pair instead of register asm s390/mm,pages-states: get rid of register asm s390/lib,xor: get rid of register asm s390/timex: get rid of register asm s390/hypfs: use register pair instead of register asm s390/zcrypt: Switch to flexible array member s390/speculation: Use statically initialized const for instructions virtio/s390: get rid of open-coded kvm hypercall s390/pci: add zpci_set_irq()/zpci_clear_irq() scripts/min-tool-version.sh: Raise minimum clang version to 13.0.0 for s390 s390/ipl: use register pair instead of register asm s390/mem_detect: fix tprot() program check new psw handling ...
2021-06-18s390/hvc_iucv: Remove power management supportJulian Wiedmann
Power management support was removed for s390 with commit 394216275c7d ("s390: remove broken hibernate / power management support"). Remove the hvc_iucv_driver, but keep the device struct around so that it can continue to provide the hvc_iucv_dev_attr_groups attributes. Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-05-23tty: hvc: udbg_hvc: retry putc on -EAGAINNathan Lynch
hvterm_raw_put_chars() calls hvc_put_chars(), which may return -EAGAIN when the underlying hcall returns a "busy" status, but udbg_hvc_putc() doesn't handle this. When using xmon on a PowerVM guest, this can result in incomplete or garbled output when printing relatively large amounts of data quickly, such as when dumping the kernel log buffer. Call again on -EAGAIN. Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210514214422.3019105-1-nathanl@linux.ibm.com
2021-05-21tty: hvc_console: Remove the repeated words 'no' and 'from'Xiaofei Tan
Remove the repeated words 'no' and 'from', reported by checkpatch.pl. Signed-off-by: Xiaofei Tan <tanxiaofei@huawei.com> Link: https://lore.kernel.org/r/1621565558-26118-1-git-send-email-tanxiaofei@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-13tty: hvc_iucv: Drop unnecessary NULL check after container_ofGuenter Roeck
The result of container_of() operations is never NULL unless the extracted element is the first element of the embedded structure. This is not the case here. The NULL check is therefore unnecessary and misleading. Remove it. This change was made automatically with the following Coccinelle script. @@ type t; identifier v; statement s; @@ <+... ( t v = container_of(...); | v = container_of(...); ) ... when != v - if (\( !v \| v == NULL \) ) s ...+> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Link: https://lore.kernel.org/r/20210511012519.2359074-1-linux@roeck-us.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-13tty: make tty_operations::chars_in_buffer return uintJiri Slaby
tty_operations::chars_in_buffer is another hook which is expected to return values >= 0. So make it explicit by the return type too -- use unsigned int. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com> Acked-by: David Sterba <dsterba@suse.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Samuel Iglesias Gonsalvez <siglesias@igalia.com> Cc: Jens Taprogge <jens.taprogge@taprogge.org> Cc: Karsten Keil <isdn@linux-pingi.de> Cc: Ulf Hansson <ulf.hansson@linaro.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Lin <dtwlin@gmail.com> Cc: Johan Hovold <johan@kernel.org> Cc: Alex Elder <elder@kernel.org> Cc: Jiri Kosina <jikos@kernel.org> Cc: Shawn Guo <shawnguo@kernel.org> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Oliver Neukum <oneukum@suse.com> Cc: Felipe Balbi <balbi@kernel.org> Cc: Mathias Nyman <mathias.nyman@intel.com> Cc: Marcel Holtmann <marcel@holtmann.org> Cc: Johan Hedberg <johan.hedberg@gmail.com> Cc: Luiz Augusto von Dentz <luiz.dentz@gmail.com> Link: https://lore.kernel.org/r/20210505091928.22010-27-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-13tty: make tty_operations::write_room return uintJiri Slaby
Line disciplines expect a positive value or zero returned from tty->ops->write_room (invoked by tty_write_room). So make this assumption explicit by using unsigned int as a return value. Both of tty->ops->write_room and tty_write_room. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Laurentiu Tudor <laurentiu.tudor@nxp.com> Acked-by: Alex Elder <elder@linaro.org> Acked-by: Max Filippov <jcmvbkbc@gmail.com> # xtensa Acked-by: David Sterba <dsterba@suse.com> Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Helge Deller <deller@gmx.de> Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at> Cc: Chris Zankel <chris@zankel.net> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Samuel Iglesias Gonsalvez <siglesias@igalia.com> Cc: Jens Taprogge <jens.taprogge@taprogge.org> Cc: Karsten Keil <isdn@linux-pingi.de> Cc: Scott Branden <scott.branden@broadcom.com> Cc: Ulf Hansson <ulf.hansson@linaro.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Lin <dtwlin@gmail.com> Cc: Johan Hovold <johan@kernel.org> Cc: Jiri Kosina <jikos@kernel.org> Cc: Shawn Guo <shawnguo@kernel.org> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Oliver Neukum <oneukum@suse.com> Cc: Felipe Balbi <balbi@kernel.org> Cc: Mathias Nyman <mathias.nyman@intel.com> Cc: Marcel Holtmann <marcel@holtmann.org> Cc: Johan Hedberg <johan.hedberg@gmail.com> Cc: Luiz Augusto von Dentz <luiz.dentz@gmail.com> Link: https://lore.kernel.org/r/20210505091928.22010-23-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-10tty: hvc: make symbol 'hvc_udbg_dev' staticYu Kuai
The sparse tool complains as follows: drivers/tty/hvc/hvc_udbg.c:20:19: warning: symbol 'hvc_udbg_dev' was not declared. Should it be static? This symbol is not used outside of hvc_udbg.c, so this commit marks it static. Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Yu Kuai <yukuai3@huawei.com> Link: https://lore.kernel.org/r/20210407125826.4139130-1-yukuai3@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-15Merge 5.12-rc3 into tty-nextGreg Kroah-Hartman
Resolves a merge issue with: drivers/tty/hvc/hvcs.c and we want the tty/serial fixes from 5.12-rc3 in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-10tty: hvc, drop unneeded forward declarationsJiri Slaby
Forward declarations make the code larger and rewrites harder. Harder as they are often omitted from global changes. Remove forward declarations which are not really needed, i.e. the definition of the function is before its first use. Cc: linuxppc-dev@lists.ozlabs.org Reviewed-by: Tyrel Datwyler <tyreld@linux.ibm.com> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20210302062214.29627-40-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-02vio: make remove callback return voidUwe Kleine-König
The driver core ignores the return value of struct bus_type::remove() because there is only little that can be done. To simplify the quest to make this function return void, let struct vio_driver::remove() return void, too. All users already unconditionally return 0, this commit makes it obvious that returning an error code is a bad idea. Note there are two nominally different implementations for a vio bus: one in arch/sparc/kernel/vio.c and the other in arch/powerpc/platforms/pseries/vio.c. This patch only adapts the powerpc one. Before this patch for a device that was bound to a driver without a remove callback vio_cmo_bus_remove(viodev) wasn't called. As the device core still considers the device unbound after vio_bus_remove() returns calling this unconditionally is the consistent behaviour which is implemented here. Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org> Reviewed-by: Tyrel Datwyler <tyreld@linux.ibm.com> Acked-by: Lijun Pan <ljp@linux.ibm.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [mpe: Drop unneeded hvcs_remove() forward declaration, squash in change from sfr to drop ibmvnic_remove() forward declaration] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210225221834.160083-1-uwe@kleine-koenig.org
2021-01-15tty: hvcs: Drop unnecessary if blockUwe Kleine-König
If hvcs_probe() succeeded dev_set_drvdata() is called with a non-NULL value, and if hvcs_probe() failed hvcs_remove() isn't called. So there is no way dev_get_drvdata() can return NULL in hvcs_remove() and the check can just go away. Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20210114175718.137483-2-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07tty_port: drop last traces of low_latencyJiri Slaby
The main purpose of tty_port::low_latency was removed in commit a9c3f68f3cd8 (tty: Fix low_latency BUG) back in 2014. It was left in place for drivers as an optional tune knob. But only one driver has been using it until the previous commit. So remove this misconcept completely, given there are no users. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20210105120239.28031-11-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-06tty: hvc: hvc_opal: Staticify function invoked by referenceLee Jones
Fixes the following W=1 kernel build warning(s): drivers/tty/hvc/hvc_opal.c:106:6: warning: no previous prototype for ‘hvc_opal_hvsi_hangup’ [-Wmissing-prototypes] Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jirislaby@kernel.org> Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Lee Jones <lee.jones@linaro.org> Link: https://lore.kernel.org/r/20201104193549.4026187-34-lee.jones@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-06tty: hvc: hvc_vio: Staticify function invoked only by referenceLee Jones
Fixes the following W=1 kernel build warning(s): drivers/tty/hvc/hvc_vio.c:181:6: warning: no previous prototype for ‘hvterm_hvsi_hangup’ [-Wmissing-prototypes] 181 | void hvterm_hvsi_hangup(struct hvc_struct *hp, int data) | ^~~~~~~~~~~~~~~~~~ Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jirislaby@kernel.org> Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Lee Jones <lee.jones@linaro.org> Link: https://lore.kernel.org/r/20201104193549.4026187-33-lee.jones@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-27tty: hvc: fix link error with CONFIG_SERIAL_CORE_CONSOLE=nYang Yingliang
aarch64-linux-gnu-ld: drivers/tty/hvc/hvc_dcc.o: in function `dcc_early_write': hvc_dcc.c:(.text+0x164): undefined reference to `uart_console_write' The driver uses the uart_console_write(), but SERIAL_CORE_CONSOLE is not selected, so uart_console_write is not defined, then we get the error. Fix this by selecting SERIAL_CORE_CONSOLE. Fixes: d1a1af2cdf19 ("hvc: dcc: Add earlycon support") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Link: https://lore.kernel.org/r/20200919063535.2809707-1-yangyingliang@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-04tty: hvcs: Don't NULL tty->driver_data until hvcs_cleanup()Tyrel Datwyler
The code currently NULLs tty->driver_data in hvcs_close() with the intent of informing the next call to hvcs_open() that device needs to be reconfigured. However, when hvcs_cleanup() is called we copy hvcsd from tty->driver_data which was previoulsy NULLed by hvcs_close() and our call to tty_port_put(&hvcsd->port) doesn't actually do anything since &hvcsd->port ends up translating to NULL by chance. This has the side effect that when hvcs_remove() is called we have one too many port references preventing hvcs_destuct_port() from ever being called. This also prevents us from reusing the /dev/hvcsX node in a future hvcs_probe() and we can eventually run out of /dev/hvcsX devices. Fix this by waiting to NULL tty->driver_data in hvcs_cleanup(). Fixes: 27bf7c43a19c ("TTY: hvcs, add tty install") Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com> Link: https://lore.kernel.org/r/20200820234643.70412-1-tyreld@linux.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-23treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva
Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-06-25hvc: unify console setup namingSergey Senozhatsky
Use the 'common' foo_console_setup() naming scheme. There are 71 foo_console_setup() callbacks and only one foo_setup_console(). Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20200619172240.754910-1-sergey.senozhatsky@gmail.com
2020-06-25tty: hvc: Return proper error code from console ->setup() hookAndy Shevchenko
For unifying console ->setup() handling, which is poorly documented, return error code, rather than non-zero arbitrary number. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20200618164751.56828-5-andriy.shevchenko@linux.intel.com
2020-05-27tty: hvc_console, fix crashes on parallel open/closeJiri Slaby
hvc_open sets tty->driver_data to NULL when open fails at some point. Typically, the failure happens in hp->ops->notifier_add(). If there is a racing process which tries to open such mangled tty, which was not closed yet, the process will crash in hvc_open as tty->driver_data is NULL. All this happens because close wants to know whether open failed or not. But ->open should not NULL this and other tty fields for ->close to be happy. ->open should call tty_port_set_initialized(true) and close should check by tty_port_initialized() instead. So do this properly in this driver. So this patch removes these from ->open: * tty_port_tty_set(&hp->port, NULL). This happens on last close. * tty->driver_data = NULL. Dtto. * tty_port_put(&hp->port). This happens in shutdown and until now, this must have been causing a reference underflow, if I am not missing something. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: stable <stable@vger.kernel.org> Reported-and-tested-by: Raghavendra <rananta@codeaurora.org> Link: https://lore.kernel.org/r/20200526145632.13879-1-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-12Revert "tty: hvc: Fix data abort due to race in hvc_open"Greg Kroah-Hartman
This reverts commit e2bd1dcbe1aa34ff5570b3427c530e4332ecf0fe. In discussion on the mailing list, it has been determined that this is not the correct type of fix for this issue. Revert it so that we can do this correctly. Reported-by: Jiri Slaby <jslaby@suse.cz> Reported-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20200428032601.22127-1-rananta@codeaurora.org Cc: Raghavendra Rao Ananta <rananta@codeaurora.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-11Merge 5.7-rc5 into tty-nextGreg Kroah-Hartman
We need the tty fixes in here too. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-29Merge tag 'riscv-for-linus-5.7-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V fixes from Palmer Dabbelt: "A handful of fixes. Specifically: - fix linker argument to allow linking with lld - build fix for configurations without a frame pointer - a handful of build fixes related the SBI 0.1 vs 0.2 split - remove STRICT_KERNEL_RWX for !MMU, which isn't useful" * tag 'riscv-for-linus-5.7-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: riscv: select ARCH_HAS_STRICT_KERNEL_RWX only if MMU riscv: sbi: Fix undefined reference to sbi_shutdown tty: riscv: Using RISCV_SBI_V01 instead of RISCV_SBI riscv: sbi: Correct sbi_shutdown() and sbi_clear_ipi() export riscv: fix vdso build with lld RISC-V: stacktrace: Declare sp_in_global outside ifdef
2020-04-28tty: hvc: Fix data abort due to race in hvc_openRaghavendra Rao Ananta
Potentially, hvc_open() can be called in parallel when two tasks calls open() on /dev/hvcX. In such a scenario, if the hp->ops->notifier_add() callback in the function fails, where it sets the tty->driver_data to NULL, the parallel hvc_open() can see this NULL and cause a memory abort. Hence, serialize hvc_open and check if tty->private_data is NULL before proceeding ahead. The issue can be easily reproduced by launching two tasks simultaneously that does nothing but open() and close() on /dev/hvcX. For example: $ ./simple_open_close /dev/hvc0 & ./simple_open_close /dev/hvc0 & Signed-off-by: Raghavendra Rao Ananta <rananta@codeaurora.org> Link: https://lore.kernel.org/r/20200428032601.22127-1-rananta@codeaurora.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-27Merge 5.7-rc3 into tty-nextGreg Kroah-Hartman
We need the tty/serial fixes in here too. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-23tty: hvc: fix buffer overflow during hvc_alloc().Andrew Melnychenko
If there is a lot(more then 16) of virtio-console devices or virtio_console module is reloaded - buffers 'vtermnos' and 'cons_ops' are overflowed. In older kernels it overruns spinlock which leads to kernel freezing: https://bugzilla.redhat.com/show_bug.cgi?id=1786239 To reproduce the issue, you can try simple script that loads/unloads module. Something like this: while [ 1 ] do modprobe virtio_console sleep 2 modprobe -r virtio_console sleep 2 done Description of problem: Guest get 'Call Trace' when loading module "virtio_console" and unloading it frequently - clearly reproduced on kernel-4.18.0: [ 81.498208] ------------[ cut here ]------------ [ 81.499263] pvqspinlock: lock 0xffffffff92080020 has corrupted value 0xc0774ca0! [ 81.501000] WARNING: CPU: 0 PID: 785 at kernel/locking/qspinlock_paravirt.h:500 __pv_queued_spin_unlock_slowpath+0xc0/0xd0 [ 81.503173] Modules linked in: virtio_console fuse xt_CHECKSUM ipt_MASQUERADE xt_conntrack ipt_REJECT nft_counter nf_nat_tftp nft_objref nf_conntrack_tftp tun bridge stp llc nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nf_tables_set nft_chain_nat_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 nft_chain_route_ipv6 nft_chain_nat_ipv4 nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack nft_chain_route_ipv4 ip6_tables nft_compat ip_set nf_tables nfnetlink sunrpc bochs_drm drm_vram_helper ttm drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops drm i2c_piix4 pcspkr crct10dif_pclmul crc32_pclmul joydev ghash_clmulni_intel ip_tables xfs libcrc32c sd_mod sg ata_generic ata_piix virtio_net libata crc32c_intel net_failover failover serio_raw virtio_scsi dm_mirror dm_region_hash dm_log dm_mod [last unloaded: virtio_console] [ 81.517019] CPU: 0 PID: 785 Comm: kworker/0:2 Kdump: loaded Not tainted 4.18.0-167.el8.x86_64 #1 [ 81.518639] Hardware name: Red Hat KVM, BIOS 1.12.0-5.scrmod+el8.2.0+5159+d8aa4d83 04/01/2014 [ 81.520205] Workqueue: events control_work_handler [virtio_console] [ 81.521354] RIP: 0010:__pv_queued_spin_unlock_slowpath+0xc0/0xd0 [ 81.522450] Code: 07 00 48 63 7a 10 e8 bf 64 f5 ff 66 90 c3 8b 05 e6 cf d6 01 85 c0 74 01 c3 8b 17 48 89 fe 48 c7 c7 38 4b 29 91 e8 3a 6c fa ff <0f> 0b c3 0f 0b 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 48 [ 81.525830] RSP: 0018:ffffb51a01ffbd70 EFLAGS: 00010282 [ 81.526798] RAX: 0000000000000000 RBX: 0000000000000010 RCX: 0000000000000000 [ 81.528110] RDX: ffff9e66f1826480 RSI: ffff9e66f1816a08 RDI: ffff9e66f1816a08 [ 81.529437] RBP: ffffffff9153ff10 R08: 000000000000026c R09: 0000000000000053 [ 81.530732] R10: 0000000000000000 R11: ffffb51a01ffbc18 R12: ffff9e66cd682200 [ 81.532133] R13: ffffffff9153ff10 R14: ffff9e6685569500 R15: ffff9e66cd682000 [ 81.533442] FS: 0000000000000000(0000) GS:ffff9e66f1800000(0000) knlGS:0000000000000000 [ 81.534914] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 81.535971] CR2: 00005624c55b14d0 CR3: 00000003a023c000 CR4: 00000000003406f0 [ 81.537283] Call Trace: [ 81.537763] __raw_callee_save___pv_queued_spin_unlock_slowpath+0x11/0x20 [ 81.539011] .slowpath+0x9/0xe [ 81.539585] hvc_alloc+0x25e/0x300 [ 81.540237] init_port_console+0x28/0x100 [virtio_console] [ 81.541251] handle_control_message.constprop.27+0x1c4/0x310 [virtio_console] [ 81.542546] control_work_handler+0x70/0x10c [virtio_console] [ 81.543601] process_one_work+0x1a7/0x3b0 [ 81.544356] worker_thread+0x30/0x390 [ 81.545025] ? create_worker+0x1a0/0x1a0 [ 81.545749] kthread+0x112/0x130 [ 81.546358] ? kthread_flush_work_fn+0x10/0x10 [ 81.547183] ret_from_fork+0x22/0x40 [ 81.547842] ---[ end trace aa97649bd16c8655 ]--- [ 83.546539] general protection fault: 0000 [#1] SMP NOPTI [ 83.547422] CPU: 5 PID: 3225 Comm: modprobe Kdump: loaded Tainted: G W --------- - - 4.18.0-167.el8.x86_64 #1 [ 83.549191] Hardware name: Red Hat KVM, BIOS 1.12.0-5.scrmod+el8.2.0+5159+d8aa4d83 04/01/2014 [ 83.550544] RIP: 0010:__pv_queued_spin_lock_slowpath+0x19a/0x2a0 [ 83.551504] Code: c4 c1 ea 12 41 be 01 00 00 00 4c 8d 6d 14 41 83 e4 03 8d 42 ff 49 c1 e4 05 48 98 49 81 c4 40 a5 02 00 4c 03 24 c5 60 48 34 91 <49> 89 2c 24 b8 00 80 00 00 eb 15 84 c0 75 0a 41 0f b6 54 24 14 84 [ 83.554449] RSP: 0018:ffffb51a0323fdb0 EFLAGS: 00010202 [ 83.555290] RAX: 000000000000301c RBX: ffffffff92080020 RCX: 0000000000000001 [ 83.556426] RDX: 000000000000301d RSI: 0000000000000000 RDI: 0000000000000000 [ 83.557556] RBP: ffff9e66f196a540 R08: 000000000000028a R09: ffff9e66d2757788 [ 83.558688] R10: 0000000000000000 R11: 0000000000000000 R12: 646e61725f770b07 [ 83.559821] R13: ffff9e66f196a554 R14: 0000000000000001 R15: 0000000000180000 [ 83.560958] FS: 00007fd5032e8740(0000) GS:ffff9e66f1940000(0000) knlGS:0000000000000000 [ 83.562233] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 83.563149] CR2: 00007fd5022b0da0 CR3: 000000038c334000 CR4: 00000000003406e0 Signed-off-by: Andrew Melnychenko <andrew@daynix.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20200414191503.3471783-1-andrew@daynix.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-23tty: hvc: remove hvcs_driver_stringJason Yan
No users of hvcs_driver_string, remove it. This fixes the following gcc warning: drivers/tty/hvc/hvcs.c:199:19: warning: ‘hvcs_driver_string’ defined but not used [-Wunused-const-variable=] static const char hvcs_driver_string[] ^~~~~~~~~~~~~~~~~~ Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Jason Yan <yanaijie@huawei.com> Acked-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20200403071325.3721-1-yanaijie@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-21tty: riscv: Using RISCV_SBI_V01 instead of RISCV_SBIKefeng Wang
As shown in SBI v0.2, the legacy console SBI functions (sbi_console_getchar() and sbi_console_putchar()) are expected to be deprecated; they have no replacement. Let's HVC_RISCV_SBI and SERIAL_EARLYCON_RISCV_SBI depends on RISCV_SBI_V01. Fixes: efca13989250 ("RISC-V: Introduce a new config for SBI v0.1") Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-04-03Merge tag 'char-misc-5.7-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc driver updates from Greg KH: "Here is the big set of char/misc/other driver patches for 5.7-rc1. Lots of things in here, and it's later than expected due to some reverts to resolve some reported issues. All is now clean with no reported problems in linux-next. Included in here is: - interconnect updates - mei driver updates - uio updates - nvmem driver updates - soundwire updates - binderfs updates - coresight updates - habanalabs updates - mhi new bus type and core - extcon driver updates - some Kconfig cleanups - other small misc driver cleanups and updates As mentioned, all have been in linux-next for a while, and with the last two reverts, all is calm and good" * tag 'char-misc-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (174 commits) Revert "driver core: platform: Initialize dma_parms for platform devices" Revert "amba: Initialize dma_parms for amba devices" amba: Initialize dma_parms for amba devices driver core: platform: Initialize dma_parms for platform devices bus: mhi: core: Drop the references to mhi_dev in mhi_destroy_device() bus: mhi: core: Initialize bhie field in mhi_cntrl for RDDM capture bus: mhi: core: Add support for reading MHI info from device misc: rtsx: set correct pcr_ops for rts522A speakup: misc: Use dynamic minor numbers for speakup devices mei: me: add cedar fork device ids coresight: do not use the BIT() macro in the UAPI header Documentation: provide IBM contacts for embargoed hardware nvmem: core: remove nvmem_sysfs_get_groups() nvmem: core: use is_bin_visible for permissions nvmem: core: use device_register and device_unregister nvmem: core: add root_only member to nvmem device struct extcon: axp288: Add wakeup support extcon: Mark extcon_get_edev_name() function as exported symbol extcon: palmas: Hide error messages if gpio returns -EPROBE_DEFER dt-bindings: extcon: usbc-cros-ec: convert extcon-usbc-cros-ec.txt to yaml format ...
2020-03-18tty: hvc: Use the correct style for SPDX License IdentifierNishad Kamdar
This patch corrects the SPDX License Identifier style in header file related to the HVC driver. For C header files Documentation/process/license-rules.rst mandates C-like comments (opposed to C source files where C++ style should be used). Changes made by using a script provided by Joe Perches here: https://lkml.org/lkml/2019/2/7/46. Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Nishad Kamdar <nishadkamdar@gmail.com> Link: https://lore.kernel.org/r/20200301170419.GA7125@nishad Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12tty: source all tty Kconfig files in one placeRandy Dunlap
'source' (include) all of the tty/*/Kconfig files from drivers/tty/Kconfig instead of from drivers/char/Kconfig. This consolidates them both in source code and in menu presentation to the user. Move hvc/Kconfig and serial/Kconfig 'source' lines into the if TTY/endif block and remove the if TTY/endif blocks from those 2 files. Cc: linux-serial@vger.kernel.org Cc: Jiri Slaby <jslaby@suse.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Suggested-by: Jiri Slaby <jslaby@suse.com> Suggested-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Link: https://lore.kernel.org/r/20200311225736.32147-3-rdunlap@infradead.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-03Merge tag 'tty-5.5-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial updates from Greg KH: "Here is the "big" tty and serial driver patches for 5.5-rc1. It's a bit later in the merge window than normal as I wanted to make sure some last-minute patches applied to it were all sane. They seem to be :) There's a lot of little stuff in here, for the tty core, and for lots of serial drivers: - reverts of uartlite serial driver patches that were wrong - msm-serial driver fixes - serial core updates and fixes - tty core fixes - serial driver dma mapping api changes - lots of other tiny fixes and updates for serial drivers All of these have been in linux-next for a while with no reported issues" * tag 'tty-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (58 commits) Revert "serial/8250: Add support for NI-Serial PXI/PXIe+485 devices" vcs: prevent write access to vcsu devices tty: vt: keyboard: reject invalid keycodes tty: don't crash in tty_init_dev when missing tty_port serial: stm32: fix clearing interrupt error flags tty: Fix Kconfig indentation, continued serial: serial_core: Perform NULL checks for break_ctl ops tty: remove unused argument from tty_open_by_driver() tty: Fix Kconfig indentation {tty: serial, nand: onenand}: samsung: rename to fix build warning serial: ifx6x60: add missed pm_runtime_disable serial: pl011: Fix DMA ->flush_buffer() Revert "serial-uartlite: Move the uart register" Revert "serial-uartlite: Add get serial id if not provided" Revert "serial-uartlite: Do not use static struct uart_driver out of probe()" Revert "serial-uartlite: Add runtime support" Revert "serial-uartlite: Change logic how console_port is setup" Revert "serial-uartlite: Use allocated structure instead of static ones" tty: serial: msm_serial: Use dma_request_chan() directly for channel request tty: serial: tegra: Use dma_request_chan() directly for channel request ...
2019-11-21tty: Fix Kconfig indentation, continuedKrzysztof Kozlowski
Adjust indentation from seven spaces to tab (+optional two spaces) as in coding style with command like: $ sed -e 's/^ /\t/' -i */Kconfig Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Link: https://lore.kernel.org/r/20191121132847.29015-1-krzk@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-20tty: Fix Kconfig indentationKrzysztof Kozlowski
Adjust indentation from spaces to tab (+optional two spaces) as in coding style with command like: $ sed -e 's/^ /\t/' -i */Kconfig Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Link: https://lore.kernel.org/r/20191120133843.13189-1-krzk@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-13riscv: don't allow selecting SBI based drivers for M-modeDamien Le Moal
When running in M-mode we can't use SBI based drivers. Add a new CONFIG_RISCV_SBI that drivers that do SBI calls can depend on instead. Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-10-11hvc: dcc: Add earlycon supportMichal Simek
Add DCC earlycon support for early printks. The patch is useful for SoC bringup where HW serial console is broken. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Link: https://lore.kernel.org/r/41e2920a6348e65b2e986b0e65b66531e87cd756.1570543923.git.michal.simek@xilinx.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-04tty: hvcs: Fix odd use of strlcpyJoe Perches
Use the typical style of array, not the equivalent &array[0]. Signed-off-by: Joe Perches <joe@perches.com> Link: https://lore.kernel.org/r/1be432798311378947ec4e6051cad1235b6eccbb.1562283944.git.joe@perches.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-17docs: powerpc: convert docs to ReST and rename to *.rstMauro Carvalho Chehab
Convert docs to ReST and add them to the arch-specific book. The conversion here was trivial, as almost every file there was already using an elegant format close to ReST standard. The changes were mostly to mark literal blocks and add a few missing section title identifiers. One note with regards to "--": on Sphinx, this can't be used to identify a list, as it will format it badly. This can be used, however, to identify a long hyphen - and "---" is an even longer one. At its new index.rst, let's add a :orphan: while this is not linked to the main index.rst file, in order to avoid build warnings. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> # cxl
2019-06-14powerpc/pseries/hvconsole: Fix stack overread via udbgDaniel Axtens
While developing KASAN for 64-bit book3s, I hit the following stack over-read. It occurs because the hypercall to put characters onto the terminal takes 2 longs (128 bits/16 bytes) of characters at a time, and so hvc_put_chars() would unconditionally copy 16 bytes from the argument buffer, regardless of supplied length. However, udbg_hvc_putc() can call hvc_put_chars() with a single-byte buffer, leading to the error. ================================================================== BUG: KASAN: stack-out-of-bounds in hvc_put_chars+0xdc/0x110 Read of size 8 at addr c0000000023e7a90 by task swapper/0 CPU: 0 PID: 0 Comm: swapper Not tainted 5.2.0-rc2-next-20190528-02824-g048a6ab4835b #113 Call Trace: dump_stack+0x104/0x154 (unreliable) print_address_description+0xa0/0x30c __kasan_report+0x20c/0x224 kasan_report+0x18/0x30 __asan_report_load8_noabort+0x24/0x40 hvc_put_chars+0xdc/0x110 hvterm_raw_put_chars+0x9c/0x110 udbg_hvc_putc+0x154/0x200 udbg_write+0xf0/0x240 console_unlock+0x868/0xd30 register_console+0x970/0xe90 register_early_udbg_console+0xf8/0x114 setup_arch+0x108/0x790 start_kernel+0x104/0x784 start_here_common+0x1c/0x534 Memory state around the buggy address: c0000000023e7980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 c0000000023e7a00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 >c0000000023e7a80: f1 f1 01 f2 f2 f2 00 00 00 00 00 00 00 00 00 00 ^ c0000000023e7b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 c0000000023e7b80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== Document that a 16-byte buffer is requred, and provide it in udbg. Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-19Merge tag 'riscv-for-linus-5.2-mw2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux Pull RISC-V updates from Palmer Dabbelt: "This contains an assortment of RISC-V related patches that I'd like to target for the 5.2 merge window. Most of the patches are cleanups, but there are a handful of user-visible changes: - The nosmp and nr_cpus command-line arguments are now supported, which work like normal. - The SBI console no longer installs itself as a preferred console, we rely on standard mechanisms (/chosen, command-line, hueristics) instead. - sfence_remove_sfence_vma{,_asid} now pass their arguments along to the SBI call. - Modules now support BUG(). - A missing sfence.vma during boot has been added. This bug only manifests during boot. - The arch/riscv support for SiFive's L2 cache controller has been merged, which should un-block the EDAC framework work. I've only tested this on QEMU again, as I didn't have time to get things running on the Unleashed. The latest master from this morning merges in cleanly and passes the tests as well" * tag 'riscv-for-linus-5.2-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux: (31 commits) riscv: fix locking violation in page fault handler RISC-V: sifive_l2_cache: Add L2 cache controller driver for SiFive SoCs RISC-V: Add DT documentation for SiFive L2 Cache Controller RISC-V: Avoid using invalid intermediate translations riscv: Support BUG() in kernel module riscv: Add the support for c.ebreak check in is_valid_bugaddr() riscv: support trap-based WARN() riscv: fix sbi_remote_sfence_vma{,_asid}. riscv: move switch_mm to its own file riscv: move flush_icache_{all,mm} to cacheflush.c tty: Don't force RISCV SBI console as preferred console RISC-V: Access CSRs using CSR numbers RISC-V: Add interrupt related SCAUSE defines in asm/csr.h RISC-V: Use tabs to align macro values in asm/csr.h RISC-V: Fix minor checkpatch issues. RISC-V: Support nr_cpus command line option. RISC-V: Implement nosmp commandline option. RISC-V: Add RISC-V specific arch_match_cpu_phys_id riscv: vdso: drop unnecessary cc-ldoption riscv: call pm_power_off from machine_halt / machine_power_off ...
2019-05-16tty: Don't force RISCV SBI console as preferred consoleAnup Patel
The Linux kernel will auto-disables all boot consoles whenever it gets a preferred real console. Currently on RISC-V systems, if we have a real console which is not RISCV SBI console then boot consoles (such as earlycon=sbi) are not auto-disabled when a real console (ttyS0 or ttySIF0) is available. This results in duplicate prints at boot-time after kernel starts using real console (i.e. ttyS0 or ttySIF0) if "earlycon=" kernel parameter was passed by bootloader. The reason for above issue is that RISCV SBI console always adds itself as preferred console which is causing other real consoles to be not used as preferred console. Ideally "console=" kernel parameter passed by bootloaders should be the one selecting a preferred real console. This patch fixes above issue by not forcing RISCV SBI console as preferred console. Fixes: afa6b1ccfad5 ("tty: New RISC-V SBI console driver") Cc: stable@vger.kernel.org Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-04-16tty: remove redundant 'default n' from Kconfig-sBartlomiej Zolnierkiewicz
'default n' is the default value for any bool or tristate Kconfig setting so there is no need to write it explicitly. Also since commit f467c5640c29 ("kconfig: only write '# CONFIG_FOO is not set' for visible symbols") the Kconfig behavior is the same regardless of 'default n' being present or not: ... One side effect of (and the main motivation for) this change is making the following two definitions behave exactly the same: config FOO bool config FOO bool default n With this change, neither of these will generate a '# CONFIG_FOO is not set' line (assuming FOO isn't selected/implied). That might make it clearer to people that a bare 'default n' is redundant. ... Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-04tty: add SPDX identifiers to Kconfig and MakefilesGreg Kroah-Hartman
There were a few Kconfig and Makefiles under drivers/tty/ that were missing a SPDX identifier. Fix that up so that automated tools can properly classify all kernel source files. Cc: Jiri Slaby <jslaby@suse.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: Rob Herring <robh@kernel.org> Acked-by: David Sterba <dsterba@suse.com> Reviewed-by: Mukesh Ojha <mojha@codeaurora.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-26tty: hvc_xen: Mark expected switch fall-throughGustavo A. R. Silva
In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. This patch fixes the following warning: drivers/tty/hvc/hvc_xen.c: In function ‘xencons_backend_changed’: drivers/tty/hvc/hvc_xen.c:493:6: warning: this statement may fall through [-Wimplicit-fallthrough=] if (dev->state == XenbusStateClosed) ^ drivers/tty/hvc/hvc_xen.c:496:2: note: here case XenbusStateClosing: ^~~~ Warning level 3 was used: -Wimplicit-fallthrough=3 Notice that, in this particular case, the code comment is modified in accordance with what GCC is expecting to find. This patch is part of the ongoing efforts to enable -Wimplicit-fallthrough Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-17tty: Use of_node_name_{eq,prefix} for node name comparisonsRob Herring
Convert string compares of DT node names to use of_node_name_eq helper instead. This removes direct access to the node name pointer. For hvc, the code can also be simplified by using of_stdout pointer instead of searching again for the stdout node. Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.com> Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-serial@vger.kernel.org Cc: sparclinux@vger.kernel.org Signed-off-by: Rob Herring <robh@kernel.org> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-10tty: hvc: hvc_write() fix break conditionNicholas Piggin
Commit 550ddadcc758 ("tty: hvc: hvc_write() may sleep") broke the termination condition in case the driver stops accepting characters. This can result in unnecessary polling of the busy driver. Restore it by testing the hvc_push return code. Tested-by: Matteo Croce <mcroce@redhat.com> Tested-by: Jason Gunthorpe <jgg@mellanox.com> Tested-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-10tty: hvc: hvc_poll() fix read loop batchingNicholas Piggin
Commit ec97eaad1383 ("tty: hvc: hvc_poll() break hv read loop") removes get_chars batching entirely, which slows down large console operations like paste -- virtio console "feels worse than a 9600 baud serial line," reports Matteo. This adds back batching in a more latency friendly way. If the caller can sleep then we try to fill the entire flip buffer, releasing the lock and scheduling between each iteration. If it can not sleep, then batches are limited to 128 bytes. Matteo confirms this fixes the performance problem. Latency testing the powerpc OPAL console with OpenBMC UART with a large paste shows about 0.25ms latency, which seems reasonable. 10ms latencies were typical for this case before the latency breaking work, so we still see most of the benefit. kopald-1204 0d.h. 5us : hvc_poll <-hvc_handle_interrupt kopald-1204 0d.h. 5us : __hvc_poll <-hvc_handle_interrupt kopald-1204 0d.h. 5us : _raw_spin_lock_irqsave <-__hvc_poll kopald-1204 0d.h. 5us : tty_port_tty_get <-__hvc_poll kopald-1204 0d.h. 6us : _raw_spin_lock_irqsave <-tty_port_tty_get kopald-1204 0d.h. 6us : _raw_spin_unlock_irqrestore <-tty_port_tty_get kopald-1204 0d.h. 6us : tty_buffer_request_room <-__hvc_poll kopald-1204 0d.h. 7us : __tty_buffer_request_room <-__hvc_poll kopald-1204 0d.h. 7us+: opal_get_chars <-__hvc_poll kopald-1204 0d.h. 36us : tty_buffer_request_room <-__hvc_poll kopald-1204 0d.h. 36us : __tty_buffer_request_room <-__hvc_poll kopald-1204 0d.h. 36us+: opal_get_chars <-__hvc_poll kopald-1204 0d.h. 65us : tty_buffer_request_room <-__hvc_poll kopald-1204 0d.h. 65us : __tty_buffer_request_room <-__hvc_poll kopald-1204 0d.h. 66us+: opal_get_chars <-__hvc_poll kopald-1204 0d.h. 94us : tty_buffer_request_room <-__hvc_poll kopald-1204 0d.h. 95us : __tty_buffer_request_room <-__hvc_poll kopald-1204 0d.h. 95us+: opal_get_chars <-__hvc_poll kopald-1204 0d.h. 124us : tty_buffer_request_room <-__hvc_poll kopald-1204 0d.h. 124us : __tty_buffer_request_room <-__hvc_poll kopald-1204 0d.h. 125us+: opal_get_chars <-__hvc_poll kopald-1204 0d.h. 154us : tty_buffer_request_room <-__hvc_poll kopald-1204 0d.h. 154us : __tty_buffer_request_room <-__hvc_poll kopald-1204 0d.h. 154us+: opal_get_chars <-__hvc_poll kopald-1204 0d.h. 183us : tty_buffer_request_room <-__hvc_poll kopald-1204 0d.h. 184us : __tty_buffer_request_room <-__hvc_poll kopald-1204 0d.h. 184us+: opal_get_chars <-__hvc_poll kopald-1204 0d.h. 213us : tty_buffer_request_room <-__hvc_poll kopald-1204 0d.h. 213us : __tty_buffer_request_room <-__hvc_poll kopald-1204 0d.h. 213us+: opal_get_chars <-__hvc_poll kopald-1204 0d.h. 242us : _raw_spin_unlock_irqrestore <-__hvc_poll kopald-1204 0d.h. 242us : tty_flip_buffer_push <-__hvc_poll kopald-1204 0d.h. 243us : queue_work_on <-tty_flip_buffer_push kopald-1204 0d.h. 243us : tty_kref_put <-__hvc_poll kopald-1204 0d.h. 243us : hvc_kick <-hvc_handle_interrupt kopald-1204 0d.h. 243us : wake_up_process <-hvc_kick kopald-1204 0d.h. 244us : try_to_wake_up <-hvc_kick kopald-1204 0d.h. 244us : _raw_spin_lock_irqsave <-try_to_wake_up kopald-1204 0d.h. 244us : _raw_spin_unlock_irqrestore <-try_to_wake_up Reported-by: Matteo Croce <mcroce@redhat.com> Tested-by: Matteo Croce <mcroce@redhat.com> Tested-by: Jason Gunthorpe <jgg@mellanox.com> Tested-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-10tty: hvc: hvc_poll() fix read loop hangNicholas Piggin
Commit ec97eaad1383 ("tty: hvc: hvc_poll() break hv read loop") causes the virtio console to hang at times (e.g., if you paste a bunch of characters to it. The reason is that get_chars must return 0 before we can be sure the driver will kick or poll input again, but this change only scheduled a poll if get_chars had returned a full count. Change this to poll on any > 0 count. Reported-by: Matteo Croce <mcroce@redhat.com> Reported-by: Jason Gunthorpe <jgg@mellanox.com> Tested-by: Matteo Croce <mcroce@redhat.com> Tested-by: Jason Gunthorpe <jgg@mellanox.com> Tested-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>