linux/drivers
Andrew Morton 9ffee4cbc5 tty_check_change(): avoid taking tasklist_lock while holding tty->ctrl_lock
May 11 09:42:27 [kernel] [ 1104.496819] rarian-sk-get-c[5630]: segfault at 0 ip 7f478556caf0 sp 7fff8e3fe338 error 4 in libc-2.6.1.so[7f47854f9000+136000]
May 11 10:59:48 [kernel] [ 2494.165792]
May 11 10:59:48 [kernel] [ 2494.165794] =======================================================
May 11 10:59:48 [kernel] [ 2494.165801] [ INFO: possible circular locking dependency detected ]
May 11 10:59:48 [kernel] [ 2494.165805] 2.6.26-rc1-00007-g91b3a7a #217
May 11 10:59:48 [kernel] [ 2494.165807] -------------------------------------------------------
May 11 10:59:48 [kernel] [ 2494.165809] less/7053 is trying to acquire lock:
May 11 10:59:48 [kernel] [ 2494.165812]  (tasklist_lock){..??}, at: [<ffffffff80232e95>] is_current_pgrp_orphaned+0x15/0x50
May 11 10:59:48 [kernel] [ 2494.165821]
May 11 10:59:48 [kernel] [ 2494.165822] but task is already holding lock:
May 11 10:59:48 [kernel] [ 2494.165824]  (&tty->ctrl_lock){....}, at: [<ffffffff803d5f31>] tty_check_change+0x61/0x110
May 11 10:59:48 [kernel] [ 2494.165831]
May 11 10:59:48 [kernel] [ 2494.165832] which lock already depends on the new lock.
May 11 10:59:48 [kernel] [ 2494.165833]
May 11 10:59:48 [kernel] [ 2494.165835]
May 11 10:59:48 [kernel] [ 2494.165836] the existing dependency chain (in reverse order) is:
May 11 10:59:48 [kernel] [ 2494.165838]
May 11 10:59:48 [kernel] [ 2494.165839] -> #2 (&tty->ctrl_lock){....}:
May 11 10:59:48 [kernel] [ 2494.165843]        [<ffffffff80253796>] __lock_acquire+0xf86/0x1080
May 11 10:59:48 [kernel] [ 2494.165851]        [<ffffffff80253922>] lock_acquire+0x92/0xc0
May 11 10:59:48 [kernel] [ 2494.165858]        [<ffffffff804deee0>] _spin_lock_irqsave+0x40/0x60
May 11 10:59:48 [kernel] [ 2494.165866]        [<ffffffff803d31b5>] __proc_set_tty+0x35/0xe0
May 11 10:59:48 [kernel] [ 2494.165873]        [<ffffffff803d76d4>] tty_ioctl+0xbf4/0xfe0
May 11 10:59:48 [kernel] [ 2494.165880]        [<ffffffff802a05e1>] vfs_ioctl+0x31/0x90
May 11 10:59:48 [kernel] [ 2494.165888]        [<ffffffff802a06b3>] do_vfs_ioctl+0x73/0x2d0
May 11 10:59:48 [kernel] [ 2494.165895]        [<ffffffff802a095a>] sys_ioctl+0x4a/0x80
May 11 10:59:48 [kernel] [ 2494.165902]        [<ffffffff8020b5ab>] system_call_after_swapgs+0x7b/0x80
May 11 10:59:48 [kernel] [ 2494.165910]        [<ffffffffffffffff>] 0xffffffffffffffff
May 11 10:59:48 [kernel] [ 2494.165924]
May 11 10:59:48 [kernel] [ 2494.165925] -> #1 (&sighand->siglock){++..}:
May 11 10:59:48 [kernel] [ 2494.165929]        [<ffffffff80253796>] __lock_acquire+0xf86/0x1080
May 11 10:59:48 [kernel] [ 2494.165936]        [<ffffffff80253922>] lock_acquire+0x92/0xc0
May 11 10:59:48 [kernel] [ 2494.165943]        [<ffffffff804dec1f>] _spin_lock+0x2f/0x40
May 11 10:59:48 [kernel] [ 2494.165951]        [<ffffffff8022d5a3>] copy_process+0x973/0x1210
May 11 10:59:48 [kernel] [ 2494.165959]        [<ffffffff8022df12>] do_fork+0x82/0x2f0
May 11 10:59:48 [kernel] [ 2494.165967]        [<ffffffff8020bfe1>] kernel_thread+0x81/0xde
May 11 10:59:48 [kernel] [ 2494.165974]        [<ffffffff8020c048>] child_rip+0xa/0x12
May 11 10:59:48 [kernel] [ 2494.165981]        [<ffffffffffffffff>] 0xffffffffffffffff
May 11 10:59:48 [kernel] [ 2494.166038]
May 11 10:59:48 [kernel] [ 2494.166039] -> #0 (tasklist_lock){..??}:
May 11 10:59:48 [kernel] [ 2494.166043]        [<ffffffff802535ab>] __lock_acquire+0xd9b/0x1080
May 11 10:59:48 [kernel] [ 2494.166050]        [<ffffffff80253922>] lock_acquire+0x92/0xc0
May 11 10:59:48 [kernel] [ 2494.166057]        [<ffffffff804dede2>] _read_lock+0x32/0x50
May 11 10:59:48 [kernel] [ 2494.166063]        [<ffffffff80232e95>] is_current_pgrp_orphaned+0x15/0x50
May 11 10:59:48 [kernel] [ 2494.166071]        [<ffffffff803d5f80>] tty_check_change+0xb0/0x110
May 11 10:59:48 [kernel] [ 2494.166078]        [<ffffffff803dac5f>] set_termios+0x1f/0x4c0
May 11 10:59:48 [kernel] [ 2494.166085]        [<ffffffff803db379>] tty_mode_ioctl+0x279/0x3e0
May 11 10:59:48 [kernel] [ 2494.166092]        [<ffffffff803db51d>] n_tty_ioctl+0x3d/0x260
May 11 10:59:48 [kernel] [ 2494.166100]        [<ffffffff803d6c34>] tty_ioctl+0x154/0xfe0
May 11 10:59:48 [kernel] [ 2494.166107]        [<ffffffff802a05e1>] vfs_ioctl+0x31/0x90
May 11 10:59:48 [kernel] [ 2494.166114]        [<ffffffff802a06b3>] do_vfs_ioctl+0x73/0x2d0
May 11 10:59:48 [kernel] [ 2494.166121]        [<ffffffff802a095a>] sys_ioctl+0x4a/0x80
May 11 10:59:48 [kernel] [ 2494.166128]        [<ffffffff8020b5ab>] system_call_after_swapgs+0x7b/0x80
May 11 10:59:48 [kernel] [ 2494.166135]        [<ffffffffffffffff>] 0xffffffffffffffff
May 11 10:59:48 [kernel] [ 2494.166142]
May 11 10:59:48 [kernel] [ 2494.166143] other info that might help us debug this:
May 11 10:59:48 [kernel] [ 2494.166144]
May 11 10:59:48 [kernel] [ 2494.166146] 1 lock held by less/7053:
May 11 10:59:48 [kernel] [ 2494.166148]  #0:  (&tty->ctrl_lock){....}, at: [<ffffffff803d5f31>] tty_check_change+0x61/0x110
May 11 10:59:48 [kernel] [ 2494.166155]
May 11 10:59:48 [kernel] [ 2494.166156] stack backtrace:
May 11 10:59:48 [kernel] [ 2494.166159] Pid: 7053, comm: less Not tainted 2.6.26-rc1-00007-g91b3a7a #217
May 11 10:59:48 [kernel] [ 2494.166161]
May 11 10:59:48 [kernel] [ 2494.166162] Call Trace:
May 11 10:59:48 [kernel] [ 2494.166168]  [<ffffffff80251223>] print_circular_bug_tail+0x83/0x90
May 11 10:59:48 [kernel] [ 2494.166172]  [<ffffffff80250889>] ? print_circular_bug_entry+0x49/0x60
May 11 10:59:48 [kernel] [ 2494.166178]  [<ffffffff802535ab>] __lock_acquire+0xd9b/0x1080
May 11 10:59:48 [kernel] [ 2494.166184]  [<ffffffff80232e95>] ? is_current_pgrp_orphaned+0x15/0x50
May 11 10:59:48 [kernel] [ 2494.166189]  [<ffffffff80253922>] lock_acquire+0x92/0xc0
May 11 10:59:48 [kernel] [ 2494.166206]  [<ffffffff803d5f80>] tty_check_change+0xb0/0x110
May 11 10:59:48 [kernel] [ 2494.166211]  [<ffffffff803dac5f>] set_termios+0x1f/0x4c0
May 11 10:59:48 [kernel] [ 2494.166216]  [<ffffffff803d3423>] ? tty_ldisc_try+0x23/0x60
May 11 10:59:48 [kernel] [ 2494.166220]  [<ffffffff803d3444>] ? tty_ldisc_try+0x44/0x60
May 11 10:59:48 [kernel] [ 2494.166224]  [<ffffffff804df2c5>] ? _spin_unlock_irqrestore+0x65/0x80
May 11 10:59:48 [kernel] [ 2494.166230]  [<ffffffff803db379>] tty_mode_ioctl+0x279/0x3e0
May 11 10:59:48 [kernel] [ 2494.166234]  [<ffffffff803d3444>] ? tty_ldisc_try+0x44/0x60
May 11 10:59:48 [kernel] [ 2494.166239]  [<ffffffff803db51d>] n_tty_ioctl+0x3d/0x260
May 11 10:59:48 [kernel] [ 2494.166244]  [<ffffffff803d6c34>] tty_ioctl+0x154/0xfe0
May 11 10:59:48 [kernel] [ 2494.166249]  [<ffffffff80252baa>] ? __lock_acquire+0x39a/0x1080
May 11 10:59:48 [kernel] [ 2494.166256]  [<ffffffff80252baa>] ? __lock_acquire+0x39a/0x1080
May 11 10:59:48 [kernel] [ 2494.166263]  [<ffffffff80252baa>] ? __lock_acquire+0x39a/0x1080
May 11 10:59:48 [kernel] [ 2494.166269]  [<ffffffff802a05e1>] vfs_ioctl+0x31/0x90
May 11 10:59:48 [kernel] [ 2494.166274]  [<ffffffff802a06b3>] do_vfs_ioctl+0x73/0x2d0
May 11 10:59:48 [kernel] [ 2494.166280]  [<ffffffff802a095a>] sys_ioctl+0x4a/0x80
May 11 10:59:48 [kernel] [ 2494.166286]  [<ffffffff8020b5ab>] system_call_after_swapgs+0x7b/0x80
May 11 10:59:48 [kernel] [ 2494.166292]

Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Reported-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-14 19:11:15 -07:00
..
accessibility Kconfig: improved help for CONFIG_ACCESSIBILITY 2008-05-08 10:46:55 -07:00
acorn/char
acpi Fix ACPI vs proc_create_data() mismerge 2008-04-30 16:26:27 -07:00
amba
ata pata_atiixp: Don't disable 2008-05-06 11:43:44 -04:00
atm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2008-04-30 08:45:48 -07:00
auxdisplay
base Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-2.6 2008-05-14 11:13:44 -07:00
block block: avoid duplicate calls to get_part() in disk stat code 2008-05-07 10:15:46 +02:00
bluetooth hci_usb.h: fix hard-to-trigger race 2008-05-02 16:45:10 -07:00
cdrom Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block 2008-04-29 08:18:03 -07:00
char tty_check_change(): avoid taking tasklist_lock while holding tty->ctrl_lock 2008-05-14 19:11:15 -07:00
clocksource
connector
cpufreq [CPUFREQ] state info wrong after resume 2008-04-28 16:27:08 -04:00
cpuidle
crypto
dca
dio
dma
edac dev_name introduction fall out fix 2008-05-05 15:08:38 -07:00
eisa
firewire Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6 2008-05-02 13:52:35 -07:00
firmware edd: add default mode CONFIG_EDD_OFF=n, override with edd={on,off} 2008-04-29 08:06:23 -07:00
gpio gpio: pca953x: add support for pca9555 I2C I/O expander 2008-05-01 08:04:01 -07:00
hid hid-core: use get_unaligned_* helpers 2008-04-29 08:06:27 -07:00
hwmon Merge branch 'release' of git://lm-sensors.org/kernel/mhoffman/hwmon-2.6 2008-05-01 08:28:26 -07:00
i2c [MIPS] Alchemy: SMBus resource fix 2008-05-12 16:46:50 +01:00
ide cs5520: disable VDMA 2008-05-14 23:06:16 +02:00
ieee1394 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6 2008-05-01 11:31:38 -07:00
infiniband RDMA/cxgb3: Wrap the software send queue pointer as needed on flush 2008-05-13 11:52:55 -07:00
input Merge git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6 2008-05-09 08:07:58 -07:00
isdn isdn: hysdn_procconf.c build fix 2008-05-01 08:03:59 -07:00
leds Remove duplicated unlikely() in IS_ERR() 2008-04-29 08:06:25 -07:00
lguest lguest: make Launcher see device status updates 2008-05-02 21:50:54 +10:00
macintosh [POWERPC] macintosh: ADB driver: adb_handler_sem semaphore to mutex 2008-05-05 16:47:13 +10:00
mca proc: remove proc_root from drivers 2008-04-29 08:06:18 -07:00
md Remove blkdev warning triggered by using md 2008-05-14 19:11:15 -07:00
media V4L/DVB (7900): pvrusb: Fix Kconfig if DVB=m V4L_core=y 2008-05-14 02:56:47 -03:00
memstick
message Remove duplicated unlikely() in IS_ERR() 2008-04-29 08:06:25 -07:00
mfd drivers: replace remaining __FUNCTION__ occurrences 2008-04-30 08:29:53 -07:00
misc drivers/misc/sgi-xp: replace partid_t with a short 2008-05-13 08:02:23 -07:00
mmc mmc: make one-bit signed bitfields unsigned 2008-05-13 08:02:23 -07:00
mtd mtd: solutionengine flash map depends on solution engine mach group. 2008-05-08 19:51:40 +09:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2008-05-14 10:08:24 -07:00
nubus proc: convert /proc/bus/nubus to seq_file interface 2008-04-29 08:06:19 -07:00
of
oprofile oprofile: don't request cache line alignment for cpu_buffer 2008-05-14 19:11:12 -07:00
parisc parisc: use non-racy method for proc entries creation 2008-04-29 08:06:22 -07:00
parport debugobjects: add timer specific object debugging code 2008-04-30 08:29:53 -07:00
pci ACPI/PCI: another multiple _OSC memory leak fix 2008-05-13 09:51:54 -07:00
pcmcia pcmcia: replace remaining __FUNCTION__ occurrences 2008-05-01 08:04:00 -07:00
pnp lib: create common ascii hex array 2008-05-14 19:11:14 -07:00
power Merge git://git.infradead.org/battery-2.6 2008-05-03 10:57:57 -07:00
ps3 [POWERPC] PS3: Remove unsupported wakeup sources 2008-05-02 15:00:44 +10:00
rapidio [RAPIDIO] Auto-probe the RapidIO system size 2008-04-29 19:40:28 +10:00
rtc rtc: m41t80: include <linux/kernel.h> for printk() 2008-05-13 08:02:26 -07:00
s390 [S390] tty3270: fix put_char fail/success conversion. 2008-05-07 09:23:02 +02:00
sbus sbus: Fix bpp driver build. 2008-05-05 00:33:58 -07:00
scsi Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6 2008-05-13 11:24:51 -07:00
serial m68knommu: add info about removing mcfserial 2008-05-14 19:11:12 -07:00
sh
sn
spi mpc5200_psc_spi: typo fix in header block 2008-05-14 19:11:12 -07:00
ssb
tc
telephony
thermal thermal: re-name thermal.c to thermal_sys.c 2008-04-29 03:12:17 -04:00
uio
usb USB: atmel_usba_udc fixes, mostly disconnect() 2008-05-14 10:00:30 -07:00
video video/logo: add support for Blackfin/Linux logo for framebuffer console 2008-05-14 19:11:14 -07:00
virtio virtio: explicit advertisement of driver features 2008-05-02 21:50:50 +10:00
w1 drivers: replace remaining __FUNCTION__ occurrences 2008-04-30 08:29:53 -07:00
watchdog
xen xen: add balloon driver 2008-04-24 23:57:33 +02:00
zorro zorro: use non-racy method for proc entries creation 2008-04-29 08:06:21 -07:00
Kconfig Basic braille screen reader support 2008-04-30 08:29:52 -07:00
Makefile Basic braille screen reader support 2008-04-30 08:29:52 -07:00