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2011-05-02serial/imx: read cts state only after acking cts change irqUwe Kleine-König
commit 5680e94148a86e8c31fdc5cb0ea0d5c6810c05b0 upstream. If cts changes between reading the level at the cts input (USR1_RTSS) and acking the irq (USR1_RTSD) the last edge doesn't generate an irq and uart_handle_cts_change is called with a outdated value for cts. The race was introduced by commit ceca629 ([ARM] 2971/1: i.MX uart handle rts irq) Reported-by: Arwed Springer <Arwed.Springer@de.trumpf.com> Tested-by: Arwed Springer <Arwed.Springer@de.trumpf.com> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-05-02tty/n_gsm: fix bug in CRC calculation for gsm1 modeMikhail Kshevetskiy
commit 9db4e4381a8e881ff65a5d3400bfa471f84217e7 upstream. Problem description: gsm_queue() calculate a CRC for arrived frames. As a last step of CRC calculation it call gsm->fcs = gsm_fcs_add(gsm->fcs, gsm->received_fcs); This work perfectly for the case of GSM0 mode as gsm->received_fcs contain the last piece of data required to generate final CRC. gsm->received_fcs is not used for GSM1 mode. Thus we put an additional byte to CRC calculation. As result we get a wrong CRC and reject incoming frame. Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevetskiy@gmail.com> Acked-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-03-23serial: change the divisor latch only when prescalar actually changedYin Kangkai
commit 0d0389e5414c8950b1613e8bdc74289cde3d6d98 upstream. In 8250.c original ns16550 autoconfig code, we change the divisor latch when we goto to high speed mode, we're assuming the previous speed is legacy. This some times is not true. For example in a system with both CONFIG_SERIAL_8250 and CONFIG_SERIAL_8250_PNP set, in this case, the code (autoconfig) will be called twice, one in serial8250_init/probe() and the other is from serial_pnp_probe. When serial_pnp_probe calls the autoconfig for NS16550A, it's already in high speed mode, change the divisor latch (quot << 3) in this case will make the UART console garbled. CC: Greg Kroah-Hartman <greg@kroah.com> CC: David Woodhouse <dwmw2@infradead.org> CC: linux-kernel@vger.kernel.org Signed-off-by: Yin Kangkai <kangkai.yin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-03-23serial: also set the uartclk value in resume after goes to highspeedYin Kangkai
commit 95926d2db6256e08d06b753752a0d903a0580acc upstream. For any reason if the NS16550A was not work in high speed mode (e.g. we hold NS16550A from going to high speed mode in autoconfig_16550a()), now we are resume from suspend, we should also set the uartclk to the correct value. Otherwise it is still the old 1843200 and that will bring issues. CC: Greg Kroah-Hartman <greg@kroah.com> CC: David Woodhouse <dwmw2@infradead.org> CC: linux-kernel@vger.kernel.org Signed-off-by: Yin Kangkai <kangkai.yin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-03-23serial: mrst_max3110: make buffer largerDan Carpenter
commit d8653d305ef66861c91fa7455fb8038460a7274c upstream. This is used to store the spi_device ->modalias so they have to be the same size. SPI_NAME_SIZE is 32. Signed-off-by: Dan Carpenter <error27@gmail.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-02-28fmvj18x_cs: add new idKen Kawasaki
fmvj18x_cs:add new id Toshiba lan&modem multifuction card (model name:IPC5010A) Signed-off-by: Ken Kawasaki <ken_kawasaki@spring.nifty.jp> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-02-18Merge branch 'fixes-2.6.38' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq * 'fixes-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: workqueue: make sure MAYDAY_INITIAL_TIMEOUT is at least 2 jiffies long workqueue, freezer: unify spelling of 'freeze' + 'able' to 'freezable' workqueue: wake up a worker when a rescuer is leaving a gcwq
2011-02-16workqueue, freezer: unify spelling of 'freeze' + 'able' to 'freezable'Tejun Heo
There are two spellings in use for 'freeze' + 'able' - 'freezable' and 'freezeable'. The former is the more prominent one. The latter is mostly used by workqueue and in a few other odd places. Unify the spelling to 'freezable'. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Acked-by: Dmitry Torokhov <dtor@mail.ru> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Alex Dubov <oakad@yahoo.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Steven Whitehouse <swhiteho@redhat.com>
2011-02-15Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu: m68knommu: set flow handler for secondary interrupt controller of 5249 m68knommu: remove use of IRQ_FLG_LOCK from 68360 platform support m68knommu: fix dereference of port.tty m68knommu: add missing linker __modver section m68knommu: fix mis-named variable int set_irq_chip loop m68knommu: add optimize memmove() function m68k: remove arch specific non-optimized memcmp() m68knommu: fix use of un-defined _TIF_WORK_MASK m68knommu: Rename m548x_wdt.c to m54xx_wdt.c m68knommu: fix m548x_wdt.c compilation after headers renaming m68knommu: Remove dependencies on nonexistent M68KNOMMU
2011-02-16m68knommu: fix dereference of port.ttyGreg Ungerer
The struct_tty associated with a port is now a direct pointer from within the local private driver info struct. So fix all uses of it. Signed-off-by: Greg Ungerer <gerg@uclinux.org>
2011-02-15Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Input: matrix_keypad - increase the limit of rows and columns Input: wacom - fix error path in wacom_probe() Input: ads7846 - check proper condition when freeing gpio Revert "Input: do not pass injected events back to the originating handler" Input: sysrq - rework re-inject logic Input: serio - clear pending rescans after sysfs driver rebind Input: rotary_encoder - use proper irqflags Input: wacom_w8001 - report resolution to userland
2011-02-03serial: bfin_5xx: split uart RX lock from uart port lock to avoid deadlockSonic Zhang
The RX lock is used to protect the RX buffer from concurrent access in DMA mode between the timer and RX interrupt routines. It is independent from the uart lock which is used to protect the TX buffer. It is possible for a uart TX transfer to be started up from the RX interrupt handler if low latency is enabled. So we need to split the locks to avoid deadlocking in this situation. In PIO mode, the RX lock is not necessary because the handle_simple_irq and handle_level_irq functions ensure driver interrupt handlers are called once on one core. And now that the RX path has its own lock, the TX interrupt has nothing to do with the RX path, so disabling it at the same time. Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-02-0368360serial: Plumb in rs_360_get_icount()Ben Hutchings
Commit 0587102cf9f427c185bfdeb2cef41e13ee0264b1 replaced a direct implementation of SIOCGICOUNT with an implementation of tty_operations::get_icount, but it did not actually set rs_360_ops.get_icount. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Cc: stable@kernel.org [2.6.37] Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-02-03n_gsm: copy mtu over when configuring via ioctl interfaceKen Mills
This field is settable but did not get copied. Signed-off-by: Ken Mills <ken.k.mills@intel.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-02-03virtio: console: Move file back to drivers/char/Amit Shah
Commit 728674a7e466628df2aeec6d11a2ae1ef968fb67 moved virtio_console.c to drivers/tty/hvc/ under the perception of this being an hvc driver. It was such once, but these days it has generic communication capabilities as well, so move it to drivers/char/. In the future, the hvc part from this file can be split off and moved under drivers/tty/hvc/. Signed-off-by: Amit Shah <amit.shah@redhat.com> CC: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-02-01Merge branch 'tty-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6 * 'tty-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6: tty/serial: fix apbuart build n_hdlc: fix read and write locking serial: unbreak billionton CF card tty: use for_each_console() and WARN() on sysfs failures vt: fix issue when fbcon wants to takeover a second time. Fix up trivial conflict in drivers/tty/tty_io.c
2011-01-26Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Input: wacom - pass touch resolution to clients through input_absinfo Input: wacom - add 2 Bamboo Pen and touch models Input: sysrq - ensure sysrq_enabled and __sysrq_enabled are consistent Input: sparse-keymap - fix KEY_VSW handling in sparse_keymap_setup Input: tegra-kbc - add tegra keyboard driver Input: gpio_keys - switch to using request_any_context_irq Input: serio - allow registered drivers to get status flag Input: ct82710c - return proper error code for ct82c710_open Input: bu21013_ts - added regulator support Input: bu21013_ts - remove duplicate resolution parameters Input: tnetv107x-ts - don't treat NULL clk as an error Input: tnetv107x-keypad - don't treat NULL clk as an error Fix up trivial conflicts in drivers/input/keyboard/Makefile due to additions of tc3589x/Tegra drivers
2011-01-26console: rename acquire/release_console_sem() to console_lock/unlock()Torben Hohn
The -rt patches change the console_semaphore to console_mutex. As a result, a quite large chunk of the patches changes all acquire/release_console_sem() to acquire/release_console_mutex() This commit makes things use more neutral function names which dont make implications about the underlying lock. The only real change is the return value of console_trylock which is inverted from try_acquire_console_sem() This patch also paves the way to switching console_sem from a semaphore to a mutex. [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: make console_trylock return 1 on success, per Geert] Signed-off-by: Torben Hohn <torbenh@gmx.de> Cc: Thomas Gleixner <tglx@tglx.de> Cc: Greg KH <gregkh@suse.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-22tty/serial: fix apbuart buildRandy Dunlap
Fix build errors by selecting SERIAL_CORE: ERROR: "uart_register_driver" [drivers/tty/serial/apbuart.ko] undefined! ERROR: "uart_write_wakeup" [drivers/tty/serial/apbuart.ko] undefined! ERROR: "uart_update_timeout" [drivers/tty/serial/apbuart.ko] undefined! ERROR: "uart_get_divisor" [drivers/tty/serial/apbuart.ko] undefined! ERROR: "uart_get_baud_rate" [drivers/tty/serial/apbuart.ko] undefined! ERROR: "uart_add_one_port" [drivers/tty/serial/apbuart.ko] undefined! ERROR: "uart_unregister_driver" [drivers/tty/serial/apbuart.ko] undefined! ERROR: "uart_remove_one_port" [drivers/tty/serial/apbuart.ko] undefined! Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Daniel Hellstrom <daniel@gaisler.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-01-22n_hdlc: fix read and write lockingPaul Fulghum
Fix locking in read and write code of n_hdlc line discipline. 2.6.36 replaced lock_kernel() with tty_lock(). The tty mutex is not dropped automatically when the thread sleeps like the BKL. This results in a blocked read or write holding the tty mutex and stalling operations by other devices that use the tty mutex. A review of n_hdlc read and write code shows: 1. neither BKL or tty mutex are required for correct operation 2. read can block while read data is available if data is posted between availability check and call to interruptible_sleep_on() 3. write does not set process state to TASK_INTERRUPTIBLE on each pass through the processing loop which can cause unneeded scheduling of the thread The unnecessary tty mutex references have been removed. Read changed to use same code as n_tty read for completing reads and blocking. Write corrected to set process state to TASK_INTERRUPTIBLE on each pass through processing loop. Signed-off-by: Paul Fulghum <paulkf@microgate.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-01-22serial: unbreak billionton CF cardPavel Machek
Unbreak Billionton CF bluetooth card. This actually fixes a regression on zaurus. Signed-off-by: Pavel Machek <pavel@ucw.cz> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-01-22tty: use for_each_console() and WARN() on sysfs failuresKay Sievers
This fixes the build warnings in the tty code, and uses the proper function for iterating over the console devices. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-01-22vt: fix issue when fbcon wants to takeover a second time.Dave Airlie
With framebuffer handover and multiple GPUs, we get into a position where the fbcon unbinds the vesafb framebuffer for GPU 1, but we still have a radeon framebuffer bound from GPU 0, so we don't unregister the console driver. Then when we tried to bind the new radeon framebuffer for GPU1 we never get to the bind call as we fail due to the console being registered already. This changes the return value to -EBUSY when the driver is already registered and continues to bind for -EBUSY. Signed-off-by: Dave Airlie <airlied@redhat.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-01-20Merge branch 'akpm'Linus Torvalds
* akpm: kernel/smp.c: consolidate writes in smp_call_function_interrupt() kernel/smp.c: fix smp_call_function_many() SMP race memcg: correctly order reading PCG_USED and pc->mem_cgroup backlight: fix 88pm860x_bl macro collision drivers/leds/ledtrig-gpio.c: make output match input, tighten input checking MAINTAINERS: update Atmel AT91 entry mm: fix truncate_setsize() comment memcg: fix rmdir, force_empty with THP memcg: fix LRU accounting with THP memcg: fix USED bit handling at uncharge in THP memcg: modify accounting function for supporting THP better fs/direct-io.c: don't try to allocate more than BIO_MAX_PAGES in a bio mm: compaction: prevent division-by-zero during user-requested compaction mm/vmscan.c: remove duplicate include of compaction.h memblock: fix memblock_is_region_memory() thp: keep highpte mapped until it is no longer needed kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT
2011-01-20Merge branch 'tty-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6 * 'tty-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6: tty: update MAINTAINERS file due to driver movement tty: move drivers/serial/ to drivers/tty/serial/ tty: move hvc drivers to drivers/tty/hvc/
2011-01-13tty: move drivers/serial/ to drivers/tty/serial/Greg Kroah-Hartman
The serial drivers are really just tty drivers, so move them to drivers/tty/ to make things a bit neater overall. This is part of the tty/serial driver movement proceedure as proposed by Arnd Bergmann and approved by everyone involved a number of months ago. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Rogier Wolff <R.E.Wolff@bitwizard.nl> Cc: Michael H. Warfield <mhw@wittsend.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-01-13tty: move hvc drivers to drivers/tty/hvc/Greg Kroah-Hartman
As requested by Arnd Bergmann, the hvc drivers are now moved to the drivers/tty/hvc/ directory. The virtio_console.c driver was also moved, as it required the hvc_console.h file to be able to be built, and it really is a hvc driver. Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-01-07Merge branch 'tty-next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6 * 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6: (36 commits) serial: apbuart: Fixup apbuart_console_init() TTY: Add tty ioctl to figure device node of the system console. tty: add 'active' sysfs attribute to tty0 and console device drivers: serial: apbuart: Handle OF failures gracefully Serial: Avoid unbalanced IRQ wake disable during resume tty: fix typos/errors in tty_driver.h comments pch_uart : fix warnings for 64bit compile 8250: fix uninitialized FIFOs ip2: fix compiler warning on ip2main_pci_tbl specialix: fix compiler warning on specialix_pci_tbl rocket: fix compiler warning on rocket_pci_ids 8250: add a UPIO_DWAPB32 for 32 bit accesses 8250: use container_of() instead of casting serial: omap-serial: Add support for kernel debugger serial: fix pch_uart kconfig & build drivers: char: hvc: add arm JTAG DCC console support RS485 documentation: add 16C950 UART description serial: ifx6x60: fix memory leak serial: ifx6x60: free IRQ on error Serial: EG20T: add PCH_UART driver ... Fixed up conflicts in drivers/serial/apbuart.c with evil merge that makes the code look fairly sane (unlike either side).
2010-12-16TTY: Add tty ioctl to figure device node of the system console.Werner Fink
This has been in the SuSE kernels for a very long time. Signed-off-by: Werner Fink <werner@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-12-16tty: add 'active' sysfs attribute to tty0 and console deviceKay Sievers
tty: add 'active' sysfs attribute to tty0 and console device Userspace can query the actual virtual console, and the configured console devices behind /dev/tt0 and /dev/console. The last entry in the list of devices is the active device, analog to the console= kernel command line option. The attribute supports poll(), which is raised when the virtual console is changed or /dev/console is reconfigured. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> index 0000000..b138b66
2010-12-16n_gsm: gsm_data_alloc buffer allocation could fail and it is not being checkedKen Mills
gsm_data_alloc buffer allocation could fail and it is not being checked. Add check for allocated buffer and return if the buffer allocation fails. Signed-off-by: Ken Mills <ken.k.mills@intel.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-12-16n_gsm: Fix message length handling when building headerKen Mills
Fix message length handling when building header When the message length is greater than 127, the length field in the header is built incorrectly. According to the spec, when the length is less than 128 the length field is a single byte formatted as: bbbbbbb1. When it is greater than 127 then the field is two bytes of the format: bbbbbbb0 bbbbbbbb. Signed-off-by: Ken Mills <ken.k.mills@intel.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-12-02Merge branch 'tty-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6 * 'tty-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6: serial: mfd: adjust the baud rate setting TTY: open/hangup race fixup TTY: don't allow reopen when ldisc is changing NET: wan/x25, fix ldisc->open retval TTY: ldisc, fix open flag handling serial8250: Mark console as CON_ANYTIME
2010-11-29TTY: open/hangup race fixupJiri Slaby
Like in the "TTY: don't allow reopen when ldisc is changing" patch, this one fixes a TTY WARNING as described in the option 1) there: 1) __tty_hangup from tty_ldisc_hangup to tty_ldisc_enable. During this section tty_lock is held. However tty_lock is temporarily dropped in the middle of the function by tty_ldisc_hangup. The fix is to introduce a new flag which we set during the unlocked window and check it in tty_reopen too. The flag is TTY_HUPPING and is cleared after TTY_HUPPED is set. While at it, remove duplicate TTY_HUPPED set_bit. The one after calling ops->hangup seems to be more correct. But anyway, we hold tty_lock, so there should be no difference. Also document the function it does that kind of crap. Nicely reproducible with two forked children: static void do_work(const char *tty) { if (signal(SIGHUP, SIG_IGN) == SIG_ERR) exit(1); setsid(); while (1) { int fd = open(tty, O_RDWR|O_NOCTTY); if (fd < 0) continue; if (ioctl(fd, TIOCSCTTY)) continue; if (vhangup()) continue; close(fd); } exit(0); } Signed-off-by: Jiri Slaby <jslaby@suse.cz> Reported-by: <Valdis.Kletnieks@vt.edu> Reported-by: Kyle McMartin <kyle@mcmartin.ca> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-29TTY: don't allow reopen when ldisc is changingJiri Slaby
There are many WARNINGs like the following reported nowadays: WARNING: at drivers/tty/tty_io.c:1331 tty_open+0x2a2/0x49a() Hardware name: Latitude E6500 Modules linked in: Pid: 1207, comm: plymouthd Not tainted 2.6.37-rc3-mmotm1123 #3 Call Trace: [<ffffffff8103b189>] warn_slowpath_common+0x80/0x98 [<ffffffff8103b1b6>] warn_slowpath_null+0x15/0x17 [<ffffffff8128a3ab>] tty_open+0x2a2/0x49a [<ffffffff810fd53f>] chrdev_open+0x11d/0x146 ... This means tty_reopen is called without TTY_LDISC set. For further considerations, note tty_lock is held in tty_open. TTY_LDISC is cleared in: 1) __tty_hangup from tty_ldisc_hangup to tty_ldisc_enable. During this section tty_lock is held. However tty_lock is temporarily dropped in the middle of the function by tty_ldisc_hangup. 2) tty_release via tty_ldisc_release till the end of tty existence. If tty->count <= 1, tty_lock is taken, TTY_CLOSING bit set and then tty_ldisc_release called. tty_reopen checks TTY_CLOSING before checking TTY_LDISC. 3) tty_set_ldisc from tty_ldisc_halt to tty_ldisc_enable. We: * take tty_lock, set TTY_LDISC_CHANGING, put tty_lock * call tty_ldisc_halt (clear TTY_LDISC), tty_lock is _not_ held * do some other work * take tty_lock, call tty_ldisc_enable (set TTY_LDISC), put tty_lock I cannot see how 2) can be a problem, as there I see no race. OTOH, 1) and 3) can happen without problems. This patch the case 3) by checking TTY_LDISC_CHANGING along with TTY_CLOSING in tty_reopen. 1) will be fixed in the following patch. Nicely reproducible with two processes: while (1) { fd = open("/dev/ttyS1", O_RDWR); if (fd < 0) { warn("open"); continue; } close(fd); } -------- while (1) { fd = open("/dev/ttyS1", O_RDWR); ld1 = 0; ld2 = 2; while (1) { ioctl(fd, TIOCSETD, &ld1); ioctl(fd, TIOCSETD, &ld2); } close(fd); } Signed-off-by: Jiri Slaby <jslaby@suse.cz> Reported-by: <Valdis.Kletnieks@vt.edu> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-29TTY: ldisc, fix open flag handlingJiri Slaby
When a concrete ldisc open fails in tty_ldisc_open, we forget to clear TTY_LDISC_OPEN. This causes a false warning on the next ldisc open: WARNING: at drivers/char/tty_ldisc.c:445 tty_ldisc_open+0x26/0x38() Hardware name: System Product Name Modules linked in: ... Pid: 5251, comm: a.out Tainted: G W 2.6.32-5-686 #1 Call Trace: [<c1030321>] ? warn_slowpath_common+0x5e/0x8a [<c1030357>] ? warn_slowpath_null+0xa/0xc [<c119311c>] ? tty_ldisc_open+0x26/0x38 [<c11936c5>] ? tty_set_ldisc+0x218/0x304 ... So clear the bit when failing... Introduced in c65c9bc3efa (tty: rewrite the ldisc locking) back in 2.6.31-rc1. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Alan Cox <alan@linux.intel.com> Reported-by: Sergey Lapin <slapin@ossfans.org> Tested-by: Sergey Lapin <slapin@ossfans.org> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-19Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Input: fix typo in keycode validation supporting large scancodes Input: aiptek - tighten up permissions on sysfs attributes Input: sysrq - pass along lone Alt + SysRq
2010-11-11n_gsm: clean up printksAlan Cox
[Original From Ken Mills but I redid it using pr_ helpers instead] Also fix up coding style, there are two warnings left but that is where the CodingStyle tools blow up because they cannot handle if (blah) { foo } else switch (x) { case 1: } Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-11n_gsm: Fix support for legacy encodingAlan Cox
The mux supports several encoding schemes. Encoding 0 is a "not recommended" mode still sometimes used. This has now been tested with hardware that supports this mode, and found wanting. Fix the FCS handling in this mode and correct the state machine. Signed-off-by: Ken Mills <ken.k.mills@intel.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-11n_gsm: Fix length handlingKen Mills
If the mux is configured with a large mru/mtu the existing code gets the byte ordering wrong for the header. Signed-off-by: Ken Mills <ken.k.mills@intel.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-11n_gsm: Copy n2 over when configuring via ioctl interfaceKen Mills
The n2 field is settable but didn't get propogated Signed-off-by: Ken Mills <ken.k.mills@intel.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-11vcs: make proper usage of the poll flagsNicolas Pitre
Kay Sievers pointed out that usage of POLLIN is well defined by POSIX, and the current usage here doesn't follow that definition. So let's duplicate the same semantics as implemented by sysfs_poll() instead. Signed-off-by: Nicolas Pitre <nicolas.pitre@canonical.com> Acked-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-09tty_ldisc: Fix BUG() on hangupPhilippe Rétornaz
A kernel BUG when bluetooth rfcomm connection drop while the associated serial port is open is sometime triggered. It seems that the line discipline can disappear between the tty_ldisc_put and tty_ldisc_get. This patch fall back to the N_TTY line discipline if the previous discipline is not available anymore. Signed-off-by: Philippe Retornaz <philippe.retornaz@epfl.ch> Acked-by: Alan Cox <alan@linux.intel.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-09TTY: restore tty_ldisc_wait_idleJiri Slaby
It was removed in 65b770468e98 (tty-ldisc: turn ldisc user count into a proper refcount), but we need to wait for last user to quit the ldisc before we close it in tty_set_ldisc. Otherwise weird things start to happen. There might be processes waiting in tty_read->n_tty_read on tty->read_wait for input to appear and at that moment, a change of ldisc is fatal. n_tty_close is called, it frees read_buf and the waiting process is still in the middle of reading and goes nuts after it is woken. Previously we prevented close to happen when others are in ldisc ops by tty_ldisc_wait_idle in tty_set_ldisc. But the commit above removed that. So revoke the change and test whether there is 1 user (=we), and allow the close then. We can do that without ldisc/tty locks, because nobody else can open the device due to TTY_LDISC_CHANGING bit set, so we in fact wait for everybody to leave. I don't understand why tty_ldisc_lock would be needed either when the counter is an atomic variable, so this is a lockless tty_ldisc_wait_idle. On the other hand, if we fail to wait (timeout or signal), we have to reenable the halted ldiscs, so we take ldisc lock and reuse the setup path at the end of tty_set_ldisc. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Tested-by: Sebastian Andrzej Siewior <bigeasy@breakpoint.cc> LKML-Reference: <20101031104136.GA511@Chamillionaire.breakpoint.cc> LKML-Reference: <1287669539-22644-1-git-send-email-jslaby@suse.cz> Cc: Alan Cox <alan@linux.intel.com> Cc: stable@kernel.org [32, 33, 36] Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-09tty: prevent DOS in the flush_to_ldiscJiri Olsa
There's a small window inside the flush_to_ldisc function, where the tty is unlocked and calling ldisc's receive_buf function. If in this window new buffer is added to the tty, the processing might never leave the flush_to_ldisc function. This scenario will hog the cpu, causing other tty processing starving, and making it impossible to interface the computer via tty. I was able to exploit this via pty interface by sending only control characters to the master input, causing the flush_to_ldisc to be scheduled, but never actually generate any output. To reproduce, please run multiple instances of following code. - SNIP #define _XOPEN_SOURCE #include <stdlib.h> #include <stdio.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> int main(int argc, char **argv) { int i, slave, master = getpt(); char buf[8192]; sprintf(buf, "%s", ptsname(master)); grantpt(master); unlockpt(master); slave = open(buf, O_RDWR); if (slave < 0) { perror("open slave failed"); return 1; } for(i = 0; i < sizeof(buf); i++) buf[i] = rand() % 32; while(1) { write(master, buf, sizeof(buf)); } return 0; } - SNIP The attached patch (based on -next tree) fixes this by checking on the tty buffer tail. Once it's reached, the current work is rescheduled and another could run. Signed-off-by: Jiri Olsa <jolsa@redhat.com> Cc: stable <stable@kernel.org> Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-05TTY: move .gitignore from drivers/char/ to drivers/tty/vt/Greg Kroah-Hartman
The autogenerated files (consolemap_deftbl.c and defkeymap.c) need to be ignored by git, so move the .gitignore file that was doing it to the properly location now that the files have moved as well. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-05TTY: create drivers/tty/vt and move the vt code thereGreg Kroah-Hartman
The vt and other related code is moved into the drivers/tty/vt directory. Acked-by: Arnd Bergmann <arnd@arndb.de> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-05TTY: create drivers/tty and move the tty core files thereGreg Kroah-Hartman
The tty code should be in its own subdirectory and not in the char driver with all of the cruft that is currently there. Based on work done by Arnd Bergmann <arnd@arndb.de> Acked-by: Arnd Bergmann <arnd@arndb.de> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>