Eric Sandeen c2d7543851 filesystem freeze: allow SysRq emergency thaw to thaw frozen filesystems ... Now that the filesystem freeze operation has been elevated to the VFS, and is just an ioctl away, some sort of safety net for unintentionally frozen root filesystems may be in order. The timeout thaw originally proposed did not get merged, but perhaps something like this would be useful in emergencies. For example, freeze /path/to/mountpoint may freeze your root filesystem if you forgot that you had that unmounted. I chose 'j' as the last remaining character other than 'h' which is sort of reserved for help (because help is generated on any unknown character). I've tested this on a non-root fs with multiple (nested) freezers, as well as on a system rendered unresponsive due to a frozen root fs. [randy.dunlap@oracle.com: emergency thaw only if CONFIG_BLOCK enabled] Signed-off-by: Eric Sandeen <sandeen@redhat.com> Cc: Takashi Sato <t-sato@yk.jp.nec.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2009-04-01 08:59:17 -07:00
..
ABI	Merge branch 'master' into next	2009-03-24 10:52:46 +11:00
accounting
acpi
aoe
arm	Merge branch 'next-s3c-pm' of git://aeryn.fluff.org.uk/bjdooks/linux into devel	2009-03-26 22:44:43 +00:00
auxdisplay
blackfin
block	block: Repeated lines in switching-sched.txt	2009-03-26 11:01:28 +01:00
blockdev
cdrom
cgroups	cpuset: various documentation fixes and updates	2009-02-20 17:57:49 -08:00
connector	Documentation/connector/cn_test.c: don't use gfp_any()	2009-02-12 16:47:01 -08:00
console
cpu-freq	[CPUFREQ] ondemand/conservative: sanitize sampling_rate restrictions	2009-02-24 22:47:31 -05:00
cpuidle
cris
crypto
development-process
device-mapper
DocBook	proc 2/2: remove struct proc_dir_entry::owner	2009-03-31 01:14:44 +04:00
driver-model	PATCH [1/2] Documentation/driver-model/device.txt: fix struct device_attribute	2009-02-22 09:27:15 -08:00
dvb	V4L/DVB (11138): get_dvb_firmware: add support for downloading the cx2584x firmware for pvrusb2	2009-03-30 12:43:31 -03:00
early-userspace
fault-injection
fb
filesystems	mm: page_mkwrite change prototype to match fault	2009-04-01 08:59:14 -07:00
firmware_class
frv
hwmon	hwmon: Define a standard interface for chassis intrusion detection	2009-03-30 21:46:44 +02:00
i2c	Move the pcf8591 driver to hwmon	2009-03-30 21:46:43 +02:00
i2o
ia64
ide
infiniband
input
ioctl	V4L/DVB (10870a): remove all references for video_decoder.h	2009-03-30 12:43:15 -03:00
isdn
ja_JP
kbuild
kdump
ko_KR
laptops
lguest	lguest: barrier me harder	2009-03-30 21:55:26 +10:30
m68k
make
mips
mn10300
mtd
namespaces
netlabel
networking	ipv6: Fix incorrect disable_ipv6 behavior	2009-03-18 18:22:48 -07:00
parisc
PCI	PCI: Documentation: fix minor PCIe HOWTO thinko	2009-02-13 13:59:19 -08:00
pcmcia
power
powerpc	Merge commit 'origin/master' into next	2009-03-30 14:04:53 +11:00
prctl
RCU	rcu: documentation 1Q09 update	2009-03-10 15:55:11 -07:00
s390
scheduler	sched, documentation: remove old O(1) scheduler document	2009-03-02 12:02:52 +01:00
scsi	[SCSI] osd: Documentation for OSD library	2009-03-12 12:58:09 -05:00
serial
sh
sound	Merge branch 'topic/oxygen' into for-linus	2009-03-24 00:36:17 +01:00
sparc
spi
sysctl
telephony
thermal
timers
tracers	doc: mmiotrace.txt, buffer size control change	2009-02-15 20:05:13 +01:00
uml
usb	USB: usbmon: Add binary API v1	2009-03-24 16:20:36 -07:00
video4linux	V4L/DVB (11225): v4lgrab: fix compilation warnings	2009-03-30 12:43:41 -03:00
vm
w1
watchdog
wimax
x86	Merge branch 'x86/doc' into x86/core	2009-03-05 21:49:44 +01:00
zh_CN
00-INDEX
applying-patches.txt
atomic_ops.txt
bad_memory.txt
basic_profiling.txt
binfmt_misc.txt
braille-console.txt
bt8xxgpio.txt
BUG-HUNTING
c2port.txt
cachetlb.txt
Changes
CodingStyle
cpu-hotplug.txt
cpu-load.txt
cputopology.txt
credentials.txt
dcdbas.txt
debugging-modules.txt
debugging-via-ohci1394.txt
dell_rbu.txt
devices.txt	[SCSI] major.h: char-major number for OSD device driver	2009-03-12 12:58:05 -05:00
DMA-API.txt	dma-debug: Documentation update	2009-03-17 12:56:47 +01:00
DMA-attributes.txt
DMA-ISA-LPC.txt
DMA-mapping.txt
dmaengine.txt
dontdiff	dontdiff: Fix asm exclude	2009-03-26 15:45:43 -07:00
dynamic-debug-howto.txt	Dynamic debug: allow simple quoting of words	2009-03-24 16:38:27 -07:00
edac.txt
eisa.txt
email-clients.txt
exception.txt
feature-removal-schedule.txt	mm: reintroduce and deprecate rlimit based access for SHM_HUGETLB	2009-04-01 08:59:12 -07:00
ftrace.txt
gpio.txt
highuid.txt
HOWTO
hw_random.txt
ics932s401
initrd.txt
Intel-IOMMU.txt
io_ordering.txt
io-mapping.txt
IO-mapping.txt
iostats.txt
IPMI.txt
IRQ-affinity.txt
IRQ.txt
irqflags-tracing.txt
isapnp.txt
java.txt
kernel-doc-nano-HOWTO.txt	kernel-doc: preferred ending marker and examples	2009-02-11 14:25:36 -08:00
kernel-docs.txt
kernel-parameters.txt	Merge branch 'iommu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2009-03-30 13:41:00 -07:00
keys-request-key.txt
keys.txt
kobject.txt
kprobes.txt
kref.txt
ldm.txt
leds-class.txt
local_ops.txt
lockdep-design.txt	lockdep: get_user_chars() redo	2009-02-14 23:28:22 +01:00
lockstat.txt
logo.svg	linux.conf.au 2009: Tuz	2009-03-16 07:55:37 -07:00
logo.txt	linux.conf.au 2009: Tuz	2009-03-16 07:55:37 -07:00
magic-number.txt
Makefile
ManagementStyle
markers.txt
mca.txt
md.txt
memory-barriers.txt
memory-hotplug.txt
memory.txt
mono.txt
mutex-design.txt
nmi_watchdog.txt
nommu-mmap.txt
numastat.txt
oops-tracing.txt
parport-lowlevel.txt
parport.txt
pi-futex.txt
pnp.txt
preempt-locking.txt
printk-formats.txt
prio_tree.txt
rbtree.txt
rfkill.txt
robust-futex-ABI.txt
robust-futexes.txt
rt-mutex-design.txt
rt-mutex.txt
rtc.txt
SAK.txt
SecurityBugs
SELinux.txt
serial-console.txt
sgi-ioc4.txt
sgi-visws.txt
SM501.txt
Smack.txt	smack: Add a new '-CIPSO' option to the network address label configuration	2009-03-28 15:01:37 +11:00
sparse.txt
spinlocks.txt
stable_api_nonsense.txt
stable_kernel_rules.txt
SubmitChecklist
SubmittingDrivers
SubmittingPatches
svga.txt
sysfs-rules.txt
sysrq.txt	filesystem freeze: allow SysRq emergency thaw to thaw frozen filesystems	2009-04-01 08:59:17 -07:00
tracepoints.txt
unaligned-memory-access.txt
unicode.txt
unshare.txt
VGA-softcursor.txt
video-output.txt
volatile-considered-harmful.txt
voyager.txt
zorro.txt