linux/fs
Eric W. Biederman 96c7a2ff21 fs/file.c:fdtable: avoid triggering OOMs from alloc_fdmem
Recently due to a spike in connections per second memcached on 3
separate boxes triggered the OOM killer from accept.  At the time the
OOM killer was triggered there was 4GB out of 36GB free in zone 1.  The
problem was that alloc_fdtable was allocating an order 3 page (32KiB) to
hold a bitmap, and there was sufficient fragmentation that the largest
page available was 8KiB.

I find the logic that PAGE_ALLOC_COSTLY_ORDER can't fail pretty dubious
but I do agree that order 3 allocations are very likely to succeed.

There are always pathologies where order > 0 allocations can fail when
there are copious amounts of free memory available.  Using the pigeon
hole principle it is easy to show that it requires 1 page more than 50%
of the pages being free to guarantee an order 1 (8KiB) allocation will
succeed, 1 page more than 75% of the pages being free to guarantee an
order 2 (16KiB) allocation will succeed and 1 page more than 87.5% of
the pages being free to guarantee an order 3 allocate will succeed.

A server churning memory with a lot of small requests and replies like
memcached is a common case that if anything can will skew the odds
against large pages being available.

Therefore let's not give external applications a practical way to kill
linux server applications, and specify __GFP_NORETRY to the kmalloc in
alloc_fdmem.  Unless I am misreading the code and by the time the code
reaches should_alloc_retry in __alloc_pages_slowpath (where
__GFP_NORETRY becomes signification).  We have already tried everything
reasonable to allocate a page and the only thing left to do is wait.  So
not waiting and falling back to vmalloc immediately seems like the
reasonable thing to do even if there wasn't a chance of triggering the
OOM killer.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Cong Wang <cwang@twopensource.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-02-10 16:01:41 -08:00
..
9p Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-01-28 08:38:04 -08:00
adfs adfs: delayed freeing of sbi 2013-10-24 23:43:27 -04:00
affs affs: use ->kill_sb() to simplify ->put_super() and failure exits of ->mount() 2014-01-25 03:13:01 -05:00
afs afs: proc cells and rootcell are writeable 2014-02-01 10:59:39 -08:00
autofs4 autofs: fix symlinks aren't checked for expiry 2014-01-23 16:36:59 -08:00
befs befs: iget_locked() doesn't return an ERR_PTR 2014-01-25 03:14:38 -05:00
bfs truncate: drop 'oldsize' truncate_pagecache() parameter 2013-09-12 15:38:02 -07:00
btrfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2014-02-09 11:12:26 -08:00
cachefiles Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-11-13 15:34:18 +09:00
ceph ceph: fix missing dput in ceph_set_acl 2014-01-31 08:14:06 -08:00
cifs fix O_SYNC|O_APPEND syncing the wrong range on write() 2014-02-09 15:18:09 -05:00
coda coda_revalidate_inode(): switch to passing inode... 2013-11-09 00:16:21 -05:00
configfs configfs: fix race between dentry put and lookup 2013-11-21 16:42:27 -08:00
cramfs cramfs: take headers to fs/cramfs 2014-01-25 03:13:02 -05:00
debugfs debugfs: use list_next_entry() in debugfs_remove_recursive() 2013-11-13 12:09:24 +09:00
devpts devpts: plug the memory leak in kill_sb 2013-11-13 12:09:36 +09:00
dlm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2014-01-25 11:17:34 -08:00
ecryptfs ecryptfs: fix failure handling in ->readlink() 2014-01-25 03:13:00 -05:00
efivarfs consolidate simple ->d_delete() instances 2013-11-15 22:04:17 -05:00
efs efs: get rid of ->put_super() 2014-01-25 03:13:02 -05:00
exofs exofs: Print less in r4w 2014-01-23 18:54:14 +02:00
exportfs exportfs: fix quadratic behavior in filehandle lookup 2013-11-09 00:16:38 -05:00
ext2 ext2/3/4: use generic posix ACL infrastructure 2014-01-25 23:58:19 -05:00
ext3 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-01-28 08:38:04 -08:00
ext4 fix O_SYNC|O_APPEND syncing the wrong range on write() 2014-02-09 15:18:09 -05:00
f2fs Merge branch 'for-3.14/core' of git://git.kernel.dk/linux-block 2014-01-30 11:19:05 -08:00
fat fat: rcu-delay unloading nls and freeing sbi 2013-10-24 23:43:28 -04:00
freevxfs [readdir] convert freevxfs 2013-06-29 12:56:53 +04:00
fscache Merge branch 'for-3.13/core' of git://git.kernel.dk/linux-block 2013-11-14 12:08:14 +09:00
fuse Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-01-28 08:38:04 -08:00
gfs2 Merge branch 'for-3.14/core' of git://git.kernel.dk/linux-block 2014-01-30 11:19:05 -08:00
hfs fs/hfs/btree.h: remove duplicate defines 2013-11-13 12:09:32 +09:00
hfsplus Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-02-01 10:43:45 -08:00
hostfs um: hostfs: make functions static 2014-01-26 11:51:09 +01:00
hpfs hpfs: optimize quad buffer loading 2014-02-02 16:24:07 -08:00
hppfs clean up scary strncpy(dst, src, strlen(src)) uses 2013-07-03 16:07:41 -07:00
hugetlbfs cope with potentially long ->d_dname() output for shmem/hugetlb 2013-08-24 12:10:17 -04:00
isofs isofs: don't pass dentry to isofs_hash{i,}_common() 2013-10-24 23:34:59 -04:00
jbd jbd: Revise KERN_EMERG error messages 2013-12-04 12:27:46 +01:00
jbd2 jbd2: rename obsoleted msg JBD->JBD2 2013-12-08 21:14:59 -05:00
jffs2 MTD updates for 3.14: 2014-01-28 18:56:37 -08:00
jfs jfs: fix generic posix ACL regression 2014-02-08 10:50:58 -06:00
kernfs kernfs: make kernfs_deactivate() honor KERNFS_LOCKDEP flag 2014-02-05 11:44:04 -08:00
lockd LOCKD: Don't call utsname()->nodename from nlmclnt_setlockargs 2013-08-05 15:03:46 -04:00
logfs Merge branch 'for-3.14/core' of git://git.kernel.dk/linux-block 2014-01-30 11:19:05 -08:00
minix fs/minix: Drop dependency on H8300 2013-09-16 18:20:25 -07:00
ncpfs ncpfs: rcu-delay unload_nls() and freeing ncp_server 2013-10-24 23:43:28 -04:00
nfs Merge branch 'acl_fixes' into linux-next 2014-02-03 17:13:45 -05:00
nfs_common
nfsd Merge branch 'for-3.14' of git://linux-nfs.org/~bfields/linux 2014-01-30 10:18:43 -08:00
nilfs2 Merge branch 'for-3.14/core' of git://git.kernel.dk/linux-block 2014-01-30 11:19:05 -08:00
nls nls: have register_nls() set ->owner 2014-01-25 03:14:05 -05:00
notify fanotify: Fix use after free for permission events 2014-01-29 13:57:17 +01:00
ntfs fix O_SYNC|O_APPEND syncing the wrong range on write() 2014-02-09 15:18:09 -05:00
ocfs2 ocfs2: free allocated clusters if error occurs after ocfs2_claim_clusters 2014-02-06 13:48:51 -08:00
omfs truncate: drop 'oldsize' truncate_pagecache() parameter 2013-09-12 15:38:02 -07:00
openpromfs [readdir] convert openpromfs 2013-06-29 12:56:32 +04:00
proc vmcore: prevent PT_NOTE p_memsz overflow during header update 2014-02-10 16:01:40 -08:00
pstore pstore: Don't allow high traffic options on fragile devices 2013-12-20 13:12:01 -08:00
qnx4 qnx4: clean qnx4_fill_super() up 2014-01-25 03:13:03 -05:00
qnx6 [readdir] convert qnx6 2013-06-29 12:56:39 +04:00
quota genetlink: make multicast groups const, prevent abuse 2013-11-19 16:39:06 -05:00
ramfs fs/ramfs: move ramfs_aops to inode.c 2014-01-23 16:36:58 -08:00
reiserfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-01-28 08:38:04 -08:00
romfs romfs: fix returm err while getting inode in fill_super 2014-01-23 16:37:04 -08:00
squashfs Squashfs: fix failure to unlock pages on decompress error 2013-11-24 01:02:50 +00:00
sysfs Revert "kernfs, sysfs, driver-core: implement kernfs_remove_self() and its wrappers" 2014-01-13 14:05:13 -08:00
sysv sysv: Add forgotten superblock lock init for v7 fs 2013-09-29 22:02:02 -04:00
ubifs fs/ubifs: use rbtree postorder iteration helper instead of opencoding 2014-01-23 16:37:03 -08:00
udf udf: Fix lockdep warning from udf_symlink() 2013-12-23 22:02:16 +01:00
ufs truncate: drop 'oldsize' truncate_pagecache() parameter 2013-09-12 15:38:02 -07:00
xfs fix O_SYNC|O_APPEND syncing the wrong range on write() 2014-02-09 15:18:09 -05:00
aio.c Merge git://git.kvack.org/~bcrl/aio-next 2013-12-22 11:03:49 -08:00
anon_inodes.c ... and kill anon_inode_getfile_private() 2013-11-09 00:16:28 -05:00
attr.c fs: fix iversion handling 2013-12-05 16:36:21 -06:00
bad_inode.c [readdir] ->readdir() is gone 2013-06-29 12:57:04 +04:00
binfmt_aout.c dump_skip(): dump_seek() replacement taking coredump_params 2013-11-09 00:16:26 -05:00
binfmt_elf_fdpic.c elf{,_fdpic} coredump: get rid of pointless if (siginfo->si_signo) 2013-11-09 00:16:30 -05:00
binfmt_elf.c fs: binfmt_elf: remove unused defines INTERPRETER_NONE and INTERPRETER_ELF 2014-01-23 16:36:58 -08:00
binfmt_em86.c file->f_op is never NULL... 2013-10-24 23:34:54 -04:00
binfmt_flat.c
binfmt_misc.c
binfmt_script.c
binfmt_som.c
bio-integrity.c bio-integrity: Fix bio_integrity_verify segment start bug 2014-01-21 20:32:05 -08:00
bio.c Revert "block: Warn and free bio if bi_end_io is not set" 2014-01-08 14:14:22 -07:00
block_dev.c a trivial writeback fix 2013-09-13 23:06:40 -04:00
buffer.c mm: __set_page_dirty uses spin_lock_irqsave instead of spin_lock_irq 2014-02-06 13:48:51 -08:00
char_dev.c Merge branch 'for-3.13/core' of git://git.kernel.dk/linux-block 2013-11-14 12:08:14 +09:00
compat_binfmt_elf.c
compat_ioctl.c fs/compat_ioctl.c: fix an underflow issue (harmless) 2014-01-21 16:19:42 -08:00
compat.c [readdir] constify ->actor 2013-06-29 12:57:05 +04:00
coredump.c coredump: make __get_dumpable/get_dumpable inline, kill fs/coredump.h 2014-01-23 16:37:01 -08:00
dcache.c __dentry_path() fixes 2014-01-26 12:37:55 -05:00
dcookies.c fs/compat: fix lookup_dcookie() parameter handling 2014-01-29 16:22:40 -08:00
direct-io.c block: Abstract out bvec iterator 2013-11-23 22:33:47 -08:00
drop_caches.c shrinker: add node awareness 2013-09-10 18:56:31 -04:00
eventfd.c eventfd_ctx_fdget(): use fdget() instead of fget() 2014-01-25 03:13:04 -05:00
eventpoll.c epoll: do not take the nested ep->mtx on EPOLL_CTL_DEL 2014-01-02 14:40:30 -08:00
exec.c execve: use 'struct filename *' for executable name passing 2014-02-05 12:54:53 -08:00
fcntl.c file->f_op is never NULL... 2013-10-24 23:34:54 -04:00
fhandle.c
file_table.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-11-13 15:34:18 +09:00
file.c fs/file.c:fdtable: avoid triggering OOMs from alloc_fdmem 2014-02-10 16:01:41 -08:00
filesystems.c
fs_struct.c seqcount: Add lockdep functionality to seqcount/seqlock structures 2013-11-06 12:40:26 +01:00
fs-writeback.c writeback: Fix data corruption on NFS 2013-12-14 04:21:26 +08:00
inode.c locks: break delegations on any attribute modification 2013-11-09 00:16:44 -05:00
internal.h get rid of s_files and files_lock 2013-11-09 00:16:20 -05:00
ioctl.c file->f_op is never NULL... 2013-10-24 23:34:54 -04:00
ioprio.c
Kconfig fs: remove generic_acl 2014-01-26 08:26:40 -05:00
Kconfig.binfmt
libfs.c consolidate simple ->d_delete() instances 2013-11-15 22:04:17 -05:00
locks.c locks: missing unlock on error in generic_add_lease() 2013-11-13 07:30:53 -05:00
Makefile Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-01-28 08:38:04 -08:00
mbcache.c fs: convert fs shrinkers to new scan/count API 2013-09-10 18:56:31 -04:00
mount.h vfs: Is mounted should be testing mnt_ns for NULL or error. 2014-01-26 08:26:42 -05:00
mpage.c block: Abstract out bvec iterator 2013-11-23 22:33:47 -08:00
namei.c execve: use 'struct filename *' for executable name passing 2014-02-05 12:54:53 -08:00
namespace.c Driver core / sysfs patches for 3.14-rc1 2014-01-20 15:49:44 -08:00
no-block.c
open.c locks: break delegations on any attribute modification 2013-11-09 00:16:44 -05:00
pipe.c fs/pipe.c: skip file_update_time on frozen fs 2014-01-23 16:37:00 -08:00
pnode.c split __lookup_mnt() in two functions 2013-10-24 23:35:00 -04:00
pnode.h vfs: Don't copy mount bind mounts of /proc/<pid>/ns/mnt between namespaces 2013-08-26 18:42:15 -07:00
posix_acl.c fs: get_acl() must be allowed to return EOPNOTSUPP 2014-02-03 17:12:37 -05:00
proc_namespace.c fs/proc_namespace.c: simplify testing nsp and nsp->mnt_ns 2014-01-23 16:37:02 -08:00
read_write.c fs/compat: fix parameter handling for compat readv/writev syscalls 2014-01-29 16:22:39 -08:00
readdir.c file->f_op is never NULL... 2013-10-24 23:34:54 -04:00
select.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-11-13 15:34:18 +09:00
seq_file.c seq_file: always clear m->count when we free m->buf 2013-11-18 19:07:53 -08:00
signalfd.c
splice.c fuse: fix pipe_buf_operations 2014-01-22 19:36:57 +01:00
stack.c
stat.c vfs: split out vfs_getattr_nosec 2013-11-09 00:16:31 -05:00
statfs.c vfs: allow O_PATH file descriptors for fstatfs() 2013-10-12 13:12:31 -07:00
super.c fs/super.c: sync ro remount after blocking writers 2014-01-31 14:29:36 -05:00
sync.c fix O_SYNC|O_APPEND syncing the wrong range on write() 2014-02-09 15:18:09 -05:00
timerfd.c
utimes.c locks: break delegations on any attribute modification 2013-11-09 00:16:44 -05:00
xattr.c