linux/Documentation
Stanislaw Gruszka c0a32fc5a2 mm: more intensive memory corruption debugging
With CONFIG_DEBUG_PAGEALLOC configured, the CPU will generate an exception
on access (read,write) to an unallocated page, which permits us to catch
code which corrupts memory.  However the kernel is trying to maximise
memory usage, hence there are usually few free pages in the system and
buggy code usually corrupts some crucial data.

This patch changes the buddy allocator to keep more free/protected pages
and to interlace free/protected and allocated pages to increase the
probability of catching corruption.

When the kernel is compiled with CONFIG_DEBUG_PAGEALLOC,
debug_guardpage_minorder defines the minimum order used by the page
allocator to grant a request.  The requested size will be returned with
the remaining pages used as guard pages.

The default value of debug_guardpage_minorder is zero: no change from
current behaviour.

[akpm@linux-foundation.org: tweak documentation, s/flg/flag/]
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10 16:30:42 -08:00
..
ABI Merge branch 'usb-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb 2012-01-09 12:09:47 -08:00
accounting
acpi ACPI, APEI, EINJ Param support is disabled by default 2011-08-03 11:15:59 -04:00
aoe
arm ARM: move iotable mappings within the vmalloc region 2011-11-26 19:21:26 -05:00
auxdisplay
blackfin doc: fix broken references 2011-09-27 18:08:04 +02:00
block Documentation: drop as block elevator reference in switching-sched.txt 2011-11-04 12:01:48 -07:00
blockdev cciss: auto engage SCSI mid layer at driver load time 2011-11-16 09:21:49 +01:00
cdrom doc: fix broken references 2011-09-27 18:08:04 +02:00
cgroups Merge branch 'for-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup 2012-01-09 12:59:24 -08:00
connector
console
cpu-freq Doc: cpufreq: Fix typo and outdated line 2011-11-08 10:23:29 +01:00
cpuidle
cris
crypto
development-process Documentation: Update stable address 2011-12-12 14:14:31 -08:00
device-mapper dm log userspace: fix comment hyphens 2011-10-31 20:21:22 +00:00
devicetree power management changes for omap and imx 2012-01-09 14:39:59 -08:00
DocBook Merge branch 'core-debugobjects-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-01-06 07:53:34 -08:00
driver-model lib: devres: add convenience function to remap a resource 2011-11-15 16:07:39 -08:00
dvb [media] update az6027 firmware URL 2011-10-14 10:29:45 -03:00
early-userspace
fault-injection fault-injection: update documentation with the mmc module param 2011-10-26 16:32:13 -04:00
fb udlfb: Enable fbcon access to framebuffer by default 2011-08-24 10:12:38 +00:00
filesystems Merge branch 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-01-08 12:19:57 -08:00
firmware_class
frv doc: fix broken references 2011-09-27 18:08:04 +02:00
hid
hwmon hwmon: (pmbus/zl6100) Add support for Ericsson BMR45[0,1] and BMR46[2,3,4] 2012-01-05 08:19:28 -08:00
i2c i2c: Fix device name for 10-bit slave address 2011-11-23 11:33:07 +01:00
i2o
ia64
ide
infiniband
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2011-10-27 08:44:20 +02:00
ioctl ioctl: register LTTng ioctl 2011-09-12 11:50:56 -07:00
isdn
ja_JP 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
kbuild
kdump [S390] Add s390x description to Documentation/kdump/kdump.txt 2011-12-27 11:27:13 +01:00
ko_KR
laptops Documentation: thinkpad-acpi grammo fixes 2011-11-04 12:01:47 -07:00
leds Documentation: fix leds-class.txt duplicated word 2011-11-04 12:01:48 -07:00
m68k Documentation: add pointer to name_to_dev_t for root= values 2011-08-03 14:25:21 -10:00
make
mips
misc-devices
mmc mmc: documentation of mmc non-blocking request usage and design. 2011-07-21 10:34:52 -04:00
mn10300
mtd
namespaces
netlabel
networking bonding: document undocumented active_slave sysfs entry. 2011-12-26 20:09:35 -05:00
nfc
parisc
PCI doc: fix broken references 2011-09-27 18:08:04 +02:00
pcmcia
power PM: Run the driver callback directly if the subsystem one is not there 2011-12-21 22:01:05 +01:00
powerpc
pps
prctl
pti
ptp
rapidio RapidIO: documentation update 2011-11-02 16:07:02 -07:00
RCU docs: Additional LWN links to RCU API 2011-12-11 10:32:23 -08:00
s390 [S390] Remove Kerntypes leftovers 2011-12-27 11:27:12 +01:00
scheduler sched: Add documentation for bandwidth control 2011-08-14 12:03:58 +02:00
scsi Merge branch 'master' into for-next 2011-11-13 20:55:53 +01:00
security doc: fix broken references 2011-09-27 18:08:04 +02:00
serial serial/documentation: fix documented name of DCD cpp symbol 2012-01-04 16:26:32 -08:00
sh
sound Merge branch 'fix/asoc' into for-linus 2011-12-06 13:22:28 +01:00
sparc
spi doc: fix broken references 2011-09-27 18:08:04 +02:00
sysctl kernel/sysctl.c: add cap_last_cap to /proc/sys/kernel 2011-10-31 17:30:53 -07:00
target
telephony
thermal
timers doc: fix broken references 2011-09-27 18:08:04 +02:00
trace mm-tracepoint: fix documentation and examples 2012-01-10 16:30:41 -08:00
usb USB: update documentation for usbmon 2012-01-04 16:04:30 -08:00
vDSO Document the vDSO and add a reference parser 2011-07-14 17:57:09 -07:00
video4linux [media] gspca - zc3xx: New webcam 03f0:1b07 HP Premium Starter Cam 2011-09-23 23:31:12 -03:00
virtual KVM: Don't automatically expose the TSC deadline timer in cpuid 2011-12-26 13:27:44 +02:00
vm Merge branches 'slab/next' and 'slub/partial' into slab/for-linus 2011-10-26 18:09:12 +03:00
w1
watchdog Documentation: watchdog: add guide how to convert drivers to new framework 2011-11-05 21:25:16 +01:00
wimax
x86 x86-64, doc: Remove int 0xcc from entry_64.S documentation 2011-08-16 08:04:08 -07:00
zh_CN remove the messy code file Documentation/zh_CN/SubmitChecklist 2011-09-26 16:18:41 -07:00
.gitignore
00-INDEX Documentation: add Ramoops usage description 2011-08-13 18:34:03 -07:00
applying-patches.txt
atomic_ops.txt doc: Add load/store guarantees to Documentation/atomic-ops.txt 2011-12-11 10:31:58 -08:00
bad_memory.txt
basic_profiling.txt
binfmt_misc.txt
braille-console.txt
bt8xxgpio.txt
btmrvl.txt
BUG-HUNTING
bus-virt-phys-mapping.txt doc: fix broken references 2011-09-27 18:08:04 +02:00
cachetlb.txt
Changes Documentation/Changes: remove some really obsolete text 2011-07-11 16:48:38 -07:00
circular-buffers.txt
coccinelle.txt
CodingStyle Documentation: update CodingStyle use of braces 2011-11-04 12:01:47 -07:00
cpu-hotplug.txt
cpu-load.txt
cputopology.txt
dcdbas.txt
debugging-modules.txt
debugging-via-ohci1394.txt
dell_rbu.txt
devices.txt devices.txt: Fix typo of 'VMware'. 2011-12-09 11:21:32 +01:00
DMA-API-HOWTO.txt Documentation/DMA-API-HOWTO.txt: fix misleading example 2011-07-26 16:49:45 -07:00
DMA-API.txt include/linux/dma-mapping.h: add dma_zalloc_coherent() 2011-11-02 16:07:02 -07:00
DMA-attributes.txt
dma-buf-sharing.txt dma-buf: Documentation for buffer sharing framework 2012-01-06 10:20:24 +00:00
DMA-ISA-LPC.txt
dmaengine.txt Improve slave/cyclic DMA engine documentation 2011-07-27 20:33:48 +05:30
dontdiff [S390] Remove Kerntypes leftovers 2011-12-27 11:27:12 +01:00
dynamic-debug-howto.txt
edac.txt
eisa.txt
email-clients.txt Documentation: email-clients: Add better Thunderbird information 2011-08-13 18:34:03 -07:00
feature-removal-schedule.txt Merge branch 'usb-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb 2012-01-09 12:09:47 -08:00
flexible-arrays.txt
futex-requeue-pi.txt
gcov.txt
gpio.txt
highuid.txt
HOWTO Documentation: Update stable address 2011-12-12 14:14:31 -08:00
hw_random.txt
hwspinlock.txt hwspinlock/core: register a bank of hwspinlocks in a single API call 2011-09-21 19:45:34 +03:00
init.txt
initrd.txt
Intel-IOMMU.txt
intel_txt.txt
io-mapping.txt
io_ordering.txt
iostats.txt
IPMI.txt
IRQ-affinity.txt
IRQ.txt
irqflags-tracing.txt
isapnp.txt
java.txt
kernel-doc-nano-HOWTO.txt
kernel-docs.txt doc: fix broken references 2011-09-27 18:08:04 +02:00
kernel-parameters.txt mm: more intensive memory corruption debugging 2012-01-10 16:30:42 -08:00
kmemcheck.txt
kmemleak.txt
kobject.txt
kprobes.txt
kref.txt
ldm.txt
local_ops.txt
lockdep-design.txt lockdep: Update documentation for lock-class leak detection 2011-12-11 10:31:23 -08:00
lockstat.txt
logo.gif
logo.txt
magic-number.txt
Makefile
ManagementStyle
mca.txt
md.txt md: create externally visible flags for supporting hot-replace. 2011-12-23 10:17:51 +11:00
media-framework.txt doc: fix broken references 2011-09-27 18:08:04 +02:00
memory-barriers.txt doc: fix broken references 2011-09-27 18:08:04 +02:00
memory-hotplug.txt
memory.txt
mono.txt
mutex-design.txt
nmi_watchdog.txt
nommu-mmap.txt
numastat.txt
oops-tracing.txt module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree 2011-11-07 07:54:42 +10:30
padata.txt
parport-lowlevel.txt
parport.txt
pi-futex.txt
pinctrl.txt drivers: create a pin control subsystem 2011-10-13 12:49:17 +02:00
pnp.txt
preempt-locking.txt
printk-formats.txt
prio_tree.txt
ramoops.txt Documentation: add Ramoops usage description 2011-08-13 18:34:03 -07:00
rbtree.txt Documentation: Update augmented rbtree documentation 2011-07-24 10:03:05 -07:00
rfkill.txt doc: fix broken references 2011-09-27 18:08:04 +02:00
robust-futex-ABI.txt
robust-futexes.txt
rt-mutex-design.txt
rt-mutex.txt
rtc.txt
SAK.txt
SecurityBugs
serial-console.txt
sgi-ioc4.txt
sgi-visws.txt
SM501.txt
sparse.txt
spinlocks.txt Documentation/spinlocks.txt: Remove reference to sti()/cli() 2011-07-11 12:45:04 -07:00
stable_api_nonsense.txt
stable_kernel_rules.txt Update email address for stable patch submission 2011-10-18 13:58:59 -07:00
SubmitChecklist Documentation/SubmitChecklist: add RCU debug config options 2011-07-25 20:57:17 -07:00
SubmittingDrivers Documentation: SubmittingDrivers: fix Linus's git tree URL 2011-08-13 18:34:03 -07:00
SubmittingPatches Documentation: fix spelling error in SubmittingPatches 2011-08-13 18:34:02 -07:00
svga.txt
sysfs-rules.txt
sysrq.txt
unaligned-memory-access.txt
unicode.txt
unshare.txt
VGA-softcursor.txt
vgaarbiter.txt misc latin1 to utf8 conversions 2012-01-02 13:04:55 +01:00
video-output.txt
volatile-considered-harmful.txt
workqueue.txt
xz.txt
zorro.txt