linux_dsm_epyc7002/Documentation/vm
David Rientjes def5efe037 mm, madvise: fail with ENOMEM when splitting vma will hit max_map_count
If madvise(2) advice will result in the underlying vma being split and
the number of areas mapped by the process will exceed
/proc/sys/vm/max_map_count as a result, return ENOMEM instead of EAGAIN.

EAGAIN is returned by madvise(2) when a kernel resource, such as slab,
is temporarily unavailable.  It indicates that userspace should retry
the advice in the near future.  This is important for advice such as
MADV_DONTNEED which is often used by malloc implementations to free
memory back to the system: we really do want to free memory back when
madvise(2) returns EAGAIN because slab allocations (for vmas, anon_vmas,
or mempolicies) cannot be allocated.

Encountering /proc/sys/vm/max_map_count is not a temporary failure,
however, so return ENOMEM to indicate this is a more serious issue.  A
followup patch to the man page will specify this behavior.

Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1701241431120.42507@chino.kir.corp.google.com
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
..
.gitignore
00-INDEX mm: introduce idle page tracking 2015-09-10 13:29:01 -07:00
active_mm.txt
balance mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd 2015-11-06 17:50:42 -08:00
cleancache.txt cleancache: forbid overriding cleancache_ops 2015-04-14 16:49:03 -07:00
frontswap.txt doc: fix quite a few typos within Documentation 2012-11-19 14:28:24 +01:00
highmem.txt
hugetlbpage.txt Documentation: vm: Spelling s/paltform/platform/g 2016-05-14 10:15:10 -06:00
hwpoison.txt mm/memory-failure.c: support use of a dedicated thread to handle SIGBUS(BUS_MCEERR_AO) 2014-06-04 16:54:13 -07:00
idle_page_tracking.txt mm: introduce idle page tracking 2015-09-10 13:29:01 -07:00
ksm.txt mm, madvise: fail with ENOMEM when splitting vma will hit max_map_count 2017-02-24 17:46:55 -08:00
numa docs: fix locations of several documents that got moved 2016-10-24 08:12:35 -02:00
numa_memory_policy.txt Documenation: update cgroup's document path 2016-08-03 15:43:58 -06:00
overcommit-accounting mm: add overcommit_kbytes sysctl variable 2014-01-21 16:19:44 -08:00
page_frags mm: add documentation for page fragment APIs 2017-01-10 18:31:55 -08:00
page_migration Three fixes for the docs build, including removing an annoying warning on 2016-08-07 10:23:17 -04:00
page_owner.txt mm, page_owner: convert page_owner_inited to static key 2016-03-15 16:55:16 -07:00
pagemap.txt Documentation typo: wrong page flag bit for KPF_HUGE 2016-04-15 15:47:10 -06:00
remap_file_pages.txt mm: replace remap_file_pages() syscall with emulation 2015-02-10 14:30:30 -08:00
slub.txt slub: convert SLAB_DEBUG_FREE to SLAB_CONSISTENCY_CHECKS 2016-03-15 16:55:16 -07:00
soft-dirty.txt mm: track vma changes with VM_SOFTDIRTY bit 2013-09-11 15:57:56 -07:00
split_page_table_lock mm: make compound_head() robust 2015-11-06 17:50:42 -08:00
transhuge.txt Merge branch 'akpm' (patches from Andrew) 2017-02-22 19:29:24 -08:00
unevictable-lru.txt Three fixes for the docs build, including removing an annoying warning on 2016-08-07 10:23:17 -04:00
userfaultfd.txt userfaultfd: documentation update 2017-02-24 17:46:55 -08:00
z3fold.txt z3fold: the 3-fold allocator for compressed pages 2016-05-20 17:58:30 -07:00
zsmalloc.txt zsmalloc: zsmalloc documentation 2015-04-15 16:35:21 -07:00
zswap.txt zswap: update docs for runtime-changeable attributes 2015-09-10 13:29:01 -07:00