linux/drivers
Thomas Gleixner b830ac1d9a rtc: fix hrtimer deadlock
Ben reported a lockup related to rtc. The lockup happens due to:

CPU0                                        CPU1

rtc_irq_set_state()			    __run_hrtimer()
  spin_lock_irqsave(&rtc->irq_task_lock)    rtc_handle_legacy_irq();
					      spin_lock(&rtc->irq_task_lock);
  hrtimer_cancel()
    while (callback_running);

So the running callback never finishes as it's blocked on
rtc->irq_task_lock.

Use hrtimer_try_to_cancel() instead and drop rtc->irq_task_lock while
waiting for the callback.  Fix this for both rtc_irq_set_state() and
rtc_irq_set_freq().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reported-by: Ben Greear <greearb@candelatech.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26 16:49:42 -07:00
..
accessibility
acpi Merge branch 'drm-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6 2011-07-26 09:21:09 -07:00
amba
ata drivers: use kzalloc/kcalloc instead of 'kmalloc+memset', where possible 2011-07-25 20:57:13 -07:00
atm lanai: use pci_dev->subsystem_device 2011-07-12 07:59:38 -07:00
auxdisplay
base drivers/base/power/opp.c: fix dev_opp initial value 2011-07-26 16:49:41 -07:00
bcma Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2011-07-25 13:56:39 -07:00
block Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client 2011-07-26 13:38:50 -07:00
bluetooth Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next-2.6 into for-davem 2011-07-15 10:05:24 -04:00
cdrom
char Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2011-07-25 13:56:39 -07:00
clk
clocksource Merge branch 'timers-clocksource-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2011-07-23 10:34:47 -07:00
connector drivers/connector/cn_proc.c: remove unused local 2011-07-25 20:57:17 -07:00
cpufreq Merge branch 'drm-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6 2011-07-26 09:21:09 -07:00
cpuidle
crypto Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2011-07-25 12:53:15 -07:00
dca
dio
dma Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2011-07-25 13:56:39 -07:00
edac
eisa eisa/pci_eisa.c: fix section mismatch 2011-07-25 20:57:14 -07:00
firewire Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6 2011-07-22 14:49:48 -07:00
firmware Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6 2011-07-25 23:06:24 -07:00
gpio Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2011-07-25 13:56:39 -07:00
gpu Merge branch 'drm-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6 2011-07-26 09:21:09 -07:00
hid Merge branches 'roccat', 'upstream' and 'wiimote' into for-linus 2011-07-22 22:47:08 +02:00
hwmon Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging 2011-07-25 14:10:34 -07:00
hwspinlock
i2c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2011-07-25 13:56:39 -07:00
ide Merge branch 'master' into for-next 2011-07-11 14:15:55 +02:00
idle
ieee802154
infiniband Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband 2011-07-22 14:50:12 -07:00
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2011-07-25 13:56:39 -07:00
iommu
isdn Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2011-07-25 13:56:39 -07:00
leds arch/arm/mach-ux500/board-u5500.c: calibrate ALS input voltage 2011-07-25 20:57:15 -07:00
lguest lguest: Fix in/out emulation 2011-07-22 14:39:51 +09:30
macintosh drivers: fix up various ->llseek() implementations 2011-07-20 20:47:58 -04:00
mca
md Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2011-07-22 19:02:39 -07:00
media Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2011-07-25 13:56:39 -07:00
memstick
message
mfd Merge branch 'master' into for-next 2011-07-11 14:15:55 +02:00
misc Merge branch 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6 2011-07-25 23:09:27 -07:00
mmc MMC / TMIO: Fix build issue related to struct scatterlist 2011-07-26 11:52:55 -07:00
mtd Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2011-07-25 13:56:39 -07:00
net Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2011-07-25 13:56:39 -07:00
nfc
nubus
of Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2011-07-25 22:59:39 -07:00
oprofile perf: Remove the nmi parameter from the oprofile_perf backend 2011-07-21 20:41:58 +02:00
parisc
parport Merge branch 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6 2011-07-25 23:09:27 -07:00
pci Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2011-07-25 13:56:39 -07:00
pcmcia Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2011-07-25 13:56:39 -07:00
platform asus-wmi: ->is_visible() can't return negative 2011-07-24 10:12:19 -04:00
pnp Merge 'akpm' patch series 2011-07-25 21:00:19 -07:00
power
pps
ps3
ptp
rapidio
regulator regulator: Convert tps65023 to use regmap API 2011-07-23 07:57:02 +01:00
rtc rtc: fix hrtimer deadlock 2011-07-26 16:49:42 -07:00
s390 [S390] dasd: add enhanced DASD statistics interface 2011-07-24 10:48:23 +02:00
sbus
scsi Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2011-07-25 13:56:39 -07:00
sfi
sh switch assorted clock drivers to debugfs_remove_recursive() 2011-07-20 20:47:51 -04:00
sn
spi Merge branch 'spi/next' of git://git.secretlab.ca/git/linux-2.6 2011-07-22 14:52:44 -07:00
ssb Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2011-07-25 13:56:39 -07:00
staging gma500: udelay(20000) it too long again 2011-07-26 11:55:14 -07:00
target Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2011-07-25 13:56:39 -07:00
tc
telephony
thermal
tty Merge branch 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6 2011-07-25 23:09:27 -07:00
uio Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6 2011-07-25 23:06:24 -07:00
usb USB / Renesas: Fix build issue related to struct scatterlist 2011-07-26 11:52:55 -07:00
uwb uwb: Fix misspelling of neighbourhood in comment 2011-07-21 14:03:41 +02:00
vhost vhost: handle wrap around in # of bufs math 2011-07-21 10:48:27 +03:00
video Merge 'akpm' patch series 2011-07-25 21:00:19 -07:00
virt drivers/virt: add missing linux/interrupt.h to fsl_hypervisor.c 2011-07-22 09:24:39 -05:00
virtio virtio: expose for non-virtualization users too 2011-07-23 16:20:30 +09:30
vlynq
w1 w1: ds1wm: add a reset recovery parameter 2011-07-08 21:14:44 -07:00
watchdog watchdog: hpwdt depends on PCI 2011-07-17 12:40:08 +00:00
xen xen/balloon: memory hotplug support for Xen balloon driver 2011-07-25 20:57:08 -07:00
zorro
Kconfig Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2011-07-25 22:59:39 -07:00
Makefile Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2011-07-25 22:59:39 -07:00