Manfred Spraul
060028bac9
ipc/shm.c: increase the defaults for SHMALL, SHMMAX ...
System V shared memory
a) can be abused to trigger out-of-memory conditions and the standard
measures against out-of-memory do not work:
- it is not possible to use setrlimit to limit the size of shm segments.
- segments can exist without association with any processes, thus
the oom-killer is unable to free that memory.
b) is typically used for shared information - today often multiple GB.
(e.g. database shared buffers)
The current default is a maximum segment size of 32 MB and a maximum
total size of 8 GB. This is often too much for a) and not enough for
b), which means that lots of users must change the defaults.
This patch increases the default limits (nearly) to the maximum, which
is perfect for case b). The defaults are used after boot and as the
initial value for each new namespace.
Admins/distros that need a protection against a) should reduce the
limits and/or enable shm_rmid_forced.
Unix has historically required setting these limits for shared memory,
and Linux inherited such behavior. The consequence of this is added
complexity for users and administrators. One very common example are
Database setup/installation documents and scripts, where users must
manually calculate the values for these limits. This also requires
(some) knowledge of how the underlying memory management works, thus
causing, in many occasions, the limits to just be flat out wrong.
Disabling these limits sooner could have saved companies a lot of time,
headaches and money for support. But it's never too late, simplify
users life now.
Further notes:
- The patch only changes default, overrides behave as before:
# sysctl kernel.shmall=33554432
would recreate the previous limit for SHMMAX (for the current namespace).
- Disabling sysv shm allocation is possible with:
# sysctl kernel.shmall=0
(not a new feature, also per-namespace)
- The limits are intentionally set to a value slightly less than ULONG_MAX,
to avoid triggering overflows in user space apps.
[not unreasonable, see http://marc.info/?l=linux-mm&m=139638334330127 ]
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Reported-by: Davidlohr Bueso <davidlohr@hp.com>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-06 16:08:14 -07:00
Updates for mmci driver:
2014-06-02 09:22:24 -07:00
clk: at91: add slow clks driver
2014-05-07 18:27:45 +02:00
fsl /bestcomm
gpio: include linux/bug.h in interface header
2014-05-16 17:52:36 +02:00
HSI: Introduce driver for SSI Protocol
2014-05-16 00:55:30 +02:00
iio: Add TEMP_AMBIENT and TEMP_OBJECT channel modifiers
2014-05-03 11:35:23 +01:00
irqchip: gic: Use mask field in GICC_IAR
2014-05-19 00:35:23 +00:00
regulator: Updates for v3.16
2014-06-03 11:44:48 -07:00
net/mlx4_core: Add UPDATE_QP SRIOV wrapper support
2014-05-16 15:12:45 -04:00
Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media into next
2014-06-04 14:24:30 -07:00
Merge remote-tracking branches 'regulator/topic/s5m8767', 'regulator/topic/stub', 'regulator/topic/tps65090', 'regulator/topic/tps65217' and 'regulator/topic/tps65218' into regulator-next
2014-06-02 17:08:12 +01:00
mm: update comment for DEFAULT_MAX_MAP_COUNT
2014-06-04 16:54:05 -07:00
Merge remote-tracking branches 'spi/topic/oom', 'spi/topic/pxa2xx', 'spi/topic/rspi' and 'spi/topic/sirf' into spi-next
2014-06-02 17:08:41 +01:00
Revert "usb: gadget: net2280: Add support for PLX USB338X"
2014-05-28 11:35:41 -07:00
Merge branch 'acpi-enumeration'
2014-06-03 23:12:20 +02:00
backlight: Add backlight device (un)registration notification
2014-05-27 01:29:01 +02:00
blk-mq: let blk_mq_tag_to_rq() take blk_mq_tags as the main parameter
2014-06-04 10:23:49 -06:00
blk-mq: improve support for shared tags maps
2014-05-13 15:10:52 -06:00
Merge branch 'akpm' (patchbomb from Andrew) into next
2014-06-04 16:55:13 -07:00
include/linux/bootmem.h: cleanup the comment for BOOTMEM_ flags
2014-06-04 16:54:04 -07:00
fs/buffer.c: remove block_write_full_page_endio()
2014-06-04 16:54:02 -07:00
cgroup: introduce task_css_is_root()
2014-05-13 11:26:27 -04:00
DeviceTree for 3.16:
2014-06-04 10:02:38 -07:00
of: consolidate linker section OF match table declarations
2014-05-20 14:25:24 -05:00
mm, compaction: embed migration mode in compact_control
2014-06-04 16:54:06 -07:00
compiler.h: avoid sparse errors in __compiletime_error_fallback()
2014-06-04 16:54:14 -07:00
connector: allow multiple messages to be sent in one packet
2014-05-27 13:56:21 -07:00
console: Use explicit pointer type for vc_uni_pagedir* fields
2014-05-28 13:37:21 -07:00
cpufreq: Fix build error on some platforms that use cpufreq_for_each_*
2014-05-08 13:10:56 +02:00
PM / suspend: Always use deepest C-state in the "freeze" sleep state
2014-05-07 01:49:28 +02:00
mm: page_alloc: use jump labels to avoid checking number_of_cpusets
2014-06-04 16:54:08 -07:00
dentry_kill(): don't try to remove from shrink list
2014-05-01 10:30:00 -04:00
PM / devfreq: Add devm_devfreq_{register,unregister}_opp_notfier function
2014-05-24 22:33:41 +09:00
Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm into next
2014-06-05 15:57:04 -07:00
cma: add placement specifier for "cma=" kernel parameter
2014-06-04 16:53:57 -07:00
Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm into next
2014-06-05 15:57:04 -07:00
dmaengine: fix dmaengine_unmap failure
2014-05-21 14:02:37 -07:00
drbd: Test cstate while holding req_lock
2014-04-30 13:46:56 -06:00
efi: Add shared FDT related functions for ARM/ARM64
2014-04-30 19:49:57 +01:00
extcon: Add devm_extcon_dev_allocate/free to manage the resource of extcon device
2014-04-29 09:45:56 +09:00
fbdev/fb.h: silence warning with -Wsign-compare
2014-05-02 15:57:42 +03:00
ALSA: firewire/bebob: Add a workaround for M-Audio special Firewire series
2014-05-26 14:33:10 +02:00
fs/libfs.c: add generic data flush to fsync
2014-06-04 16:53:55 -07:00
ftrace: Make CALLER_ADDRx macros more generic
2014-05-21 03:10:32 -04:00
include/linux/gfp.h: exclude duplicate header
2014-06-04 16:54:10 -07:00
goldfish: fix >> 32 warning
2014-05-20 10:30:40 +09:00
iio: hid-sensors: Add API to power on/off
2014-05-05 10:59:49 +01:00
iio: hid-sensors: Added device rotation support
2014-04-29 22:11:53 +01:00
Merge branches 'for-3.16/i2c-hid', 'for-3.16/rmi4', 'for-3.16/sony' and 'for-3.16/thingm' into for-linus
2014-06-04 13:09:43 +02:00
hugetlb: rename hugepage_migration_support() to ..._supported()
2014-06-04 16:54:12 -07:00
Drivers: hv: vmbus: Implement per-CPU mapping of relid to channel
2014-05-03 19:24:26 -04:00
idr: reorder the fields
2014-06-06 16:08:13 -07:00
macvlan: Fix lockdep warnings with stacked macvlan devices
2014-05-16 22:14:49 -04:00
vlan: Fix build error wth vlan_get_encap_level()
2014-05-20 11:24:26 -04:00
init.h: Update initcall_sync variants to fix build errors
2014-05-27 14:26:31 -07:00
Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next
2014-06-04 15:59:13 -07:00
genirq: Remove dynamic_irq mess
2014-05-16 14:05:22 +02:00
genirq: Sanitize spurious interrupt detection of threaded irqs
2014-05-03 23:15:39 +02:00
include/linux/jump_label.h: expose the reference count
2014-06-04 16:54:08 -07:00
kernfs: move the last knowledge of sysfs out from kernfs
2014-05-27 14:33:17 -07:00
kvm/irqchip: Speed up KVM_SET_GSI_ROUTING
2014-05-05 16:29:11 +02:00
asmlinkage: Revert "lto: Make asmlinkage __visible"
2014-05-05 16:07:37 -07:00
drivers/rtc/rtc-cmos.c: drivers/char/rtc.c features for DECstation support
2014-06-06 16:08:07 -07:00
mcb: Add support for shared PCI IRQs
2014-05-27 17:38:11 -07:00
memblock: introduce memblock_alloc_range()
2014-06-04 16:53:57 -07:00
memcg: cleanup kmem cache creation/destruction functions naming
2014-06-04 16:54:08 -07:00
mem-hotplug: implement get/put_online_mems
2014-06-04 16:53:59 -07:00
hugetlb: restrict hugepage_migration_support() to x86_64
2014-06-04 16:53:51 -07:00
mm, migration: add destination page freeing callback
2014-06-04 16:54:06 -07:00
miscdevice.h: Simple syntax fix to make pointers consistent.
2014-05-27 17:43:11 -07:00
Merge branch 'x86/vdso' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next
2014-06-05 08:05:29 -07:00
Merge branch 'x86/vdso' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next
2014-06-05 08:05:29 -07:00
mm: pass VM_BUG_ON() reason to dump_page()
2014-06-04 16:53:58 -07:00
mm: page_alloc: use unsigned int for order in more places
2014-06-04 16:54:09 -07:00
net: avoid dependency of net_get_random_once on nop patching
2014-05-14 00:37:34 -04:00
Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next
2014-06-03 12:57:53 -07:00
DeviceTree for 3.16:
2014-06-04 10:02:38 -07:00
Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm into next
2014-06-05 15:57:04 -07:00
of/fdt: add FDT address translation support
2014-05-20 15:19:25 -05:00
gpio: make of_get_named_gpiod_flags() private
2014-05-21 11:14:46 +02:00
of/irq: do irq resolution in platform_get_irq_byname()
2014-05-23 11:40:25 +09:00
net: mdio: of_mdiobus_register(): fall back to mdiobus_register() for !CONFIG_OF
2014-05-07 17:16:35 -04:00
of/irq: provide more wrappers for !CONFIG_OF
2014-06-04 04:45:46 -05:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next
2014-06-04 08:50:34 -07:00
of: consolidate linker section OF match table declarations
2014-05-20 14:25:24 -05:00
fbdev changes for 3.16 (main part)
2014-06-04 09:05:12 -07:00
mm: non-atomically mark page accessed during page cache allocation where possible
2014-06-04 16:54:10 -07:00
mm: page_alloc: reduce number of times page_to_pfn is called
2014-06-04 16:54:09 -07:00
mm: non-atomically mark page accessed during page cache allocation where possible
2014-06-04 16:54:10 -07:00
Merge branches 'pci/host-exynos', 'pci/host-imx6', 'pci/resource' and 'pci/misc' into next
2014-05-30 11:41:17 -06:00
percpu: Fix raw_cpu_inc_return()
2014-05-14 09:46:10 -07:00
Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next
2014-06-03 13:18:00 -07:00
lib/plist: add plist_requeue
2014-06-04 16:54:07 -07:00
PM / sleep: Mechanism to avoid resuming runtime-suspended devices unnecessarily
2014-05-16 23:15:44 +02:00
PM / OPP: Move cpufreq specific OPP functions out of generic OPP library
2014-05-07 00:39:03 +02:00
PM / sleep: Mechanism to avoid resuming runtime-suspended devices unnecessarily
2014-05-16 23:15:44 +02:00
power_supply: allow power supply devices registered w/o wakeup source
2014-05-30 13:45:25 +02:00
kernel/printk: use symbolic defines for console loglevels
2014-06-04 16:54:17 -07:00
init/main.c: remove an ifdef
2014-06-04 16:54:21 -07:00
ptrace: fix fork event messages across pid namespaces
2014-06-06 16:08:11 -07:00
rcu: Provide API to suppress stall warnings while sysrc runs
2014-05-19 10:52:04 -07:00
rcutorture: Export RCU grace-period kthread wait state to rcutorture
2014-05-14 09:46:09 -07:00
rcutorture: Export RCU grace-period kthread wait state to rcutorture
2014-05-14 09:46:09 -07:00
mm/rmap.c: cleanup ttu_flags
2014-06-04 16:54:12 -07:00
rtnetlink: wait for unregistering devices in rtnl_link_unregister()
2014-05-15 15:30:33 -04:00
signals: mv {dis,}allow_signal() from sched.h/exit.c to signal.[ch]
2014-06-06 16:08:11 -07:00
serial: earlycon: add DT support
2014-05-20 15:19:25 -05:00
ipc/shm.c: increase the defaults for SHMALL, SHMMAX
2014-06-06 16:08:14 -07:00
signals: introduce kernel_sigaction()
2014-06-06 16:08:12 -07:00
memcg: cleanup kmem cache creation/destruction functions naming
2014-06-04 16:54:08 -07:00
slub: use sysfs'es release mechanism for kmem_cache
2014-05-06 13:04:59 -07:00
lib: add glibc style strchrnul() variant
2014-05-23 11:23:27 +09:00
Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm into next
2014-06-05 15:57:04 -07:00
mm/vmscan.c: use DIV_ROUND_UP for calculation of zone's balance_gap and correct comments.
2014-06-04 16:54:11 -07:00
swap: change swap_list_head to plist, add swap_avail_head
2014-06-04 16:54:07 -07:00
x86: define _PAGE_NUMA by reusing software bits on the PMD and PTE levels
2014-06-04 16:53:55 -07:00
x86: enable DMA CMA with swiotlb
2014-06-04 16:53:57 -07:00
mm: constify nmask argument to set_mempolicy()
2014-06-04 16:54:03 -07:00
sysfs.h: don't return a void-valued expression in sysfs_remove_file
2014-05-27 14:29:56 -07:00
mm: get rid of __GFP_KMEMCG
2014-06-04 16:53:56 -07:00
mm: disable zone_reclaim_mode by default
2014-06-04 16:53:59 -07:00
torture: Remove unused definition
2014-05-14 09:46:32 -07:00
Revert "tty: Fix race condition between __tty_buffer_request_room and flush_to_ldisc"
2014-05-03 18:14:28 -04:00
DMA-API: Clarify physical/bus address distinction
2014-05-20 16:54:21 -06:00
ARM: 8043/1: uprobes need icache flush after xol write
2014-05-25 23:48:45 +01:00
USB: separate usb_address0 mutexes for each bus
2014-05-27 16:11:49 -07:00
ARM: vexpress: move HBI check to sysreg driver
2014-05-15 17:02:21 +01:00
mm,vmacache: add debug data
2014-06-04 16:53:57 -07:00
mm,vmacache: add debug data
2014-06-04 16:53:57 -07:00
mm/zbud.c: make size unsigned like unique callsite
2014-06-04 16:54:13 -07:00
