Vasiliy Kulikov b34a6b1da3 ipc: introduce shm_rmid_forced sysctl ... Add support for the shm_rmid_forced sysctl. If set to 1, all shared memory objects in current ipc namespace will be automatically forced to use IPC_RMID. The POSIX way of handling shmem allows one to create shm objects and call shmdt(), leaving shm object associated with no process, thus consuming memory not counted via rlimits. With shm_rmid_forced=1 the shared memory object is counted at least for one process, so OOM killer may effectively kill the fat process holding the shared memory. It obviously breaks POSIX - some programs relying on the feature would stop working. So set shm_rmid_forced=1 only if you're sure nobody uses "orphaned" memory. Use shm_rmid_forced=0 by default for compatability reasons. The feature was previously impemented in -ow as a configure option. [akpm@linux-foundation.org: fix documentation, per Randy] [akpm@linux-foundation.org: fix warning] [akpm@linux-foundation.org: readability/conventionality tweaks] [akpm@linux-foundation.org: fix shm_rmid_forced/shm_forced_rmid confusion, use standard comment layout] Signed-off-by: Vasiliy Kulikov <segoon@openwall.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: "Serge E. Hallyn" <serge.hallyn@canonical.com> Cc: Daniel Lezcano <daniel.lezcano@free.fr> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Solar Designer <solar@openwall.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2011-07-26 16:49:44 -07:00
..
compat_mq.c	ipc: initialize structure memory to zero for compat functions	2010-10-27 18:03:13 -07:00
compat.c	ipc: initialize structure memory to zero for compat functions	2010-10-27 18:03:13 -07:00
ipc_sysctl.c	ipc: introduce shm_rmid_forced sysctl	2011-07-26 16:49:44 -07:00
ipcns_notifier.c	ipc: do not use a negative value to re-enable msgmni automatic recomputing	2008-07-25 10:53:42 -07:00
Makefile	Add generic sys_ipc wrapper	2010-03-12 15:52:32 -08:00
mq_sysctl.c	sysctl ipc: Remove dead binary sysctl support code.	2009-11-12 02:04:54 -08:00
mqueue.c	ipc/mqueue.c: fix mq_open() return value	2011-07-26 16:49:44 -07:00
msg.c	Fix common misspellings	2011-03-31 11:26:23 -03:00
msgutil.c	userns: add a user namespace owner of ipc ns	2011-03-23 19:47:07 -07:00
namespace.c	ns proc: Add support for the ipc namespace	2011-05-10 14:35:47 -07:00
sem.c	ipc/sem.c: fix race with concurrent semtimedop() timeouts and IPC_RMID	2011-07-25 20:57:07 -07:00
shm.c	ipc: introduce shm_rmid_forced sysctl	2011-07-26 16:49:44 -07:00
syscall.c	ppc64 sys_ipc breakage in 2.6.34-rc2	2010-03-22 09:57:19 -07:00
util.c	ipc,rcu: Convert call_rcu(ipc_immediate_free) to kfree_rcu()	2011-07-20 14:10:16 -07:00
util.h	userns: user namespaces: convert several capable() calls	2011-03-23 19:47:08 -07:00