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* TTY: pty, fix pty countingJiri Slaby2011-08-231-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | tty_operations->remove is normally called like: queue_release_one_tty ->tty_shutdown ->tty_driver_remove_tty ->tty_operations->remove However tty_shutdown() is called from queue_release_one_tty() only if tty_operations->shutdown is NULL. But for pty, it is not. pty_unix98_shutdown() is used there as ->shutdown. So tty_operations->remove of pty (i.e. pty_unix98_remove()) is never called. This results in invalid pty_count. I.e. what can be seen in /proc/sys/kernel/pty/nr. I see this was already reported at: https://lkml.org/lkml/2009/11/5/370 But it was not fixed since then. This patch is kind of a hackish way. The problem lies in ->install. We allocate there another tty (so-called tty->link). So ->install is called once, but ->remove twice, for both tty and tty->link. The fix here is to count both tty and tty->link and divide the count by 2 for user. And to have ->remove called, let's make tty_driver_remove_tty() global and call that from pty_unix98_shutdown() (tty_operations->shutdown). While at it, let's document that when ->shutdown is defined, tty_shutdown() is not called. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Alan Cox <alan@linux.intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* drivers/tty: use printk_ratelimited() instead of printk_ratelimit()Manuel Zerpies2011-07-011-2/+2
| | | | | | | | Since the printk_ratelimit() shouldn't be used anymore (see comment in include/linux/printk.h), replace it with printk_ratelimited(). Signed-off-by: Manuel Zerpies <manuel.f.zerpies@ww.stud.uni-erlangen.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* TTY: tty_io, annotate locking functionsJiri Slaby2011-04-251-0/+2
| | | | | | | | | tty_write_lock and tty_write_unlock contain imbalanced locking. But this is intentional, so mark them appropriately by __acquires/__releases. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* tty: remove invalid location line in file headerJovi Zhang2011-04-191-2/+0
| | | | | | | | remove invalid location line in each file header after location moved from driver/char to driver/tty Signed-off-by: Jovi Zhang <bookjovi@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* TTY: fix fail path in tty_openJiri Slaby2011-04-191-0/+1
| | | | | | | | | When tty_add_file fails we omit to clean up. Fix that by calling tty_release appropriatelly. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* TTY: plug in deinitialize_tty_structJiri Slaby2011-04-191-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | Used the newly introduced deinitialize_tty_struct to properly shut down ldisc. It is intended to fix the Julian's reported problem. He reports that kmemleak checker warns about memory leak: unreferenced object 0xc0e19860 (size 8): comm cat, pid 1226, jiffies 4294919464 (age 287.476s) hex dump (first 8 bytes): 44 de 2d c1 01 00 00 00 D.-..... backtrace: [<c1065a74>] create_object+0x109/0x1ad [<c1063d2b>] kmem_cache_alloc+0x60/0x68 [<c113505c>] tty_ldisc_get+0x54/0x76 [<c11358c9>] tty_ldisc_init+0xa/0x20 [<c1130ab4>] initialize_tty_struct+0x2d/0x1ac [<c1130c8c>] tty_init_dev+0x59/0x10d [<c113136d>] tty_open+0x24a/0x3a2 ... Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Reported-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* TTY: introduce deinit helpers for proper ldisc shutdownJiri Slaby2011-04-191-0/+14
| | | | | | | | | | | | | | | | Introduce deinitialize_tty_struct which should be called after initialize_tty_struct and before successfull tty_ldisc_setup. It calls tty_ldisc_deinit which is opposite of tty_ldisc_init. It only puts a reference to ldisc and assigns NULL to tty->ldisc. It will be used to shut down ldisc when tty_release cannot be called yet. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Julian Anastasov <ja@ssi.bg> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* TTY: unify tty_init_dev fail path handlingJiri Slaby2011-04-191-11/+12
| | | | | | | | | | | | | Change it so that we call the deinit functions at one place at the end of the function (by gotos). And while at it use some sane label names. This is a preparation for the deinitialization of tty in the next patch. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Julian Anastasov <ja@ssi.bg> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* vt: remove uneeded retval check before tty->ops->open inside tty_openHerton Ronaldo Krzesinski2011-04-191-6/+4
| | | | | | | | | | The current check is uneeded, since !retval will always returns true, as retval returned from tty_add_file is checked earlier and tty_open exits if it's not zero. Acked-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Fix common misspellingsLucas De Marchi2011-03-311-4/+4
| | | | | | Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
* Merge branch 'config' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bklLinus Torvalds2011-03-161-1/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | * 'config' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl: BKL: That's all, folks fs/locks.c: Remove stale FIXME left over from BKL conversion ipx: remove the BKL appletalk: remove the BKL x25: remove the BKL ufs: remove the BKL hpfs: remove the BKL drivers: remove extraneous includes of smp_lock.h tracing: don't trace the BKL adfs: remove the big kernel lock
| * drivers: remove extraneous includes of smp_lock.hArnd Bergmann2011-03-021-1/+0
| | | | | | | | | | | | | | | | These were missed the last time I cleaned this up globally, because of code moving around or new code getting merged. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
* | tty: add TIOCVHANGUP to allow clean tty shutdown of all ttysKay Sievers2011-02-171-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | This is useful for system management software so that it can kick off things like gettys and everything that's started from a tty, before we reuse it from/for something else or shut it down. Without this ioctl it would have to temporarily become the owner of the tty, then call vhangup() and then give it up again. Cc: Lennart Poettering <lennart@poettering.net> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* | tty: now phase out the ioctl file pointer for goodAlan Cox2011-02-171-2/+2
| | | | | | | | | | | | | | | | | | Only oddities here are a couple of drivers that bogusly called the ldisc helpers instead of returning -ENOIOCTLCMD. Fix the bug and the rest goes away. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* | tiocmset: kill the file pointer argumentAlan Cox2011-02-171-4/+3
| | | | | | | | | | | | | | | | Doing tiocmget was such fun we should do tiocmset as well for the same reasons Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* | tiocmget: kill off the passing of the struct fileAlan Cox2011-02-171-3/+3
|/ | | | | | | | | | We don't actually need this and it causes problems for internal use of this functionality. Currently there is a single use of the FILE * pointer. That is the serial core which uses it to check tty_hung_up_p. However if that is true then IO_ERROR is also already set so the check may be removed. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Merge branch 'tty-linus' of ↵Linus Torvalds2011-02-011-2/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | 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
| * tty: use for_each_console() and WARN() on sysfs failuresKay Sievers2011-01-221-2/+2
| | | | | | | | | | | | | | | | 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>
* | console: rename acquire/release_console_sem() to console_lock/unlock()Torben Hohn2011-01-261-2/+2
|/ | | | | | | | | | | | | | | | | | | | | | | | | 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>
* Merge branch 'tty-next' of ↵Linus Torvalds2011-01-071-4/+48
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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).
| * TTY: Add tty ioctl to figure device node of the system console.Werner Fink2010-12-161-0/+5
| | | | | | | | | | | | | | 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>
| * tty: add 'active' sysfs attribute to tty0 and console deviceKay Sievers2010-12-161-4/+43
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* | TTY: open/hangup race fixupJiri Slaby2010-11-291-1/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | TTY: don't allow reopen when ldisc is changingJiri Slaby2010-11-291-1/+2
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* TTY: create drivers/tty and move the tty core files thereGreg Kroah-Hartman2010-11-051-0/+3263
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>
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