Cyrill Gorcunov 34228d473e mm: ignore VM_SOFTDIRTY on VMA merging ... The VM_SOFTDIRTY bit affects vma merge routine: if two VMAs has all bits in vm_flags matched except dirty bit the kernel can't longer merge them and this forces the kernel to generate new VMAs instead. It finally may lead to the situation when userspace application reaches vm.max_map_count limit and get crashed in worse case | (gimp:11768): GLib-ERROR **: gmem.c:110: failed to allocate 4096 bytes | | (file-tiff-load:12038): LibGimpBase-WARNING **: file-tiff-load: gimp_wire_read(): error | xinit: connection to X server lost | | waiting for X server to shut down | /usr/lib64/gimp/2.0/plug-ins/file-tiff-load terminated: Hangup | /usr/lib64/gimp/2.0/plug-ins/script-fu terminated: Hangup | /usr/lib64/gimp/2.0/plug-ins/script-fu terminated: Hangup https://bugzilla.kernel.org/show_bug.cgi?id=67651 https://bugzilla.gnome.org/show_bug.cgi?id=719619#c0 Initial problem came from missed VM_SOFTDIRTY in do_brk() routine but even if we would set up VM_SOFTDIRTY here, there is still a way to prevent VMAs from merging: one can call | echo 4 > /proc/$PID/clear_refs and clear all VM_SOFTDIRTY over all VMAs presented in memory map, then new do_brk() will try to extend old VMA and finds that dirty bit doesn't match thus new VMA will be generated. As discussed with Pavel, the right approach should be to ignore VM_SOFTDIRTY bit when we're trying to merge VMAs and if merge successed we mark extended VMA with dirty bit where needed. Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Reported-by: Bastian Hougaard <gnome@rvzt.net> Reported-by: Mel Gorman <mgorman@suse.de> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2014-01-23 16:36:53 -08:00
..
backing-dev.c	mm/backing-dev.c: check user buffer length before copying data to the related user buffer	2013-09-11 15:58:03 -07:00
balloon_compaction.c	mm: print more details for bad_page()	2014-01-23 16:36:50 -08:00
bootmem.c	mm/bootmem.c: remove unused local `map'	2013-11-13 12:09:09 +09:00
bounce.c	mm/bounce.c: fix a regression where MS_SNAP_STABLE (stable pages snapshotting) was ignored	2013-09-30 14:31:02 -07:00
cleancache.c	mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE	2014-01-23 16:36:50 -08:00
compaction.c	mm: improve documentation of page_order	2014-01-23 16:36:53 -08:00
debug-pagealloc.c	mm, x86: Remove debug_pagealloc_enabled	2011-12-06 09:24:07 +01:00
dmapool.c	dmapool: make DMAPOOL_DEBUG detect corruption of free marker	2012-12-11 17:22:24 -08:00
fadvise.c	teach SYSCALL_DEFINE<n> how to deal with long long/unsigned long long	2013-03-03 22:46:22 -05:00
failslab.c	switch debugfs to umode_t	2012-01-03 22:54:56 -05:00
filemap_xip.c	seqcount: Add lockdep functionality to seqcount/seqlock structures	2013-11-06 12:40:26 +01:00
filemap.c	mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE	2014-01-23 16:36:50 -08:00
fremap.c	mm: fix use-after-free in sys_remap_file_pages	2014-01-02 14:40:30 -08:00
frontswap.c	frontswap: fix incorrect zeroing and allocation size for frontswap_map	2013-06-12 16:29:46 -07:00
highmem.c	Some nice cleanups, and even a patch my wife did as a "live" demo for	2012-12-20 08:37:05 -08:00
huge_memory.c	mm: audit/fix non-modular users of module_init in core code	2014-01-23 16:36:52 -08:00
hugetlb_cgroup.c	mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE	2014-01-23 16:36:50 -08:00
hugetlb.c	mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE	2014-01-23 16:36:50 -08:00
hwpoison-inject.c	mm/hwpoison: add '#' to hwpoison_inject	2014-01-21 16:19:48 -08:00
init-mm.c	atomic: use <linux/atomic.h>	2011-07-26 16:49:47 -07:00
internal.h	mm: improve documentation of page_order	2014-01-23 16:36:53 -08:00
interval_tree.c	mm: add CONFIG_DEBUG_VM_RB build option	2012-10-09 16:22:42 +09:00
Kconfig	mm: add missing dependency in Kconfig	2013-12-18 19:04:52 -08:00
Kconfig.debug	mm: more intensive memory corruption debugging	2012-01-10 16:30:42 -08:00
kmemcheck.c
kmemleak-test.c
kmemleak.c	mm: kmemleak: avoid false negatives on vmalloc'ed objects	2013-11-13 12:09:07 +09:00
ksm.c	mm: audit/fix non-modular users of module_init in core code	2014-01-23 16:36:52 -08:00
list_lru.c	mm: list_lru: fix almost infinite loop causing effective livelock	2013-10-30 12:57:46 -07:00
maccess.c	mm: Map most files to use export.h instead of module.h	2011-10-31 09:20:12 -04:00
madvise.c	mm/hwpoison: fix traversal of hugetlbfs pages to avoid printk flood	2013-09-30 14:31:02 -07:00
Makefile	list: add a new LRU list type	2013-09-10 18:56:30 -04:00
memblock.c	mm/nobootmem: free_all_bootmem again	2014-01-23 16:36:52 -08:00
memcontrol.c	memcg: remove unused code from kmem_cache_destroy_work_func	2014-01-23 16:36:53 -08:00
memory_hotplug.c	mm/memory_hotplug.c: move register_memory_resource out of the lock_memory_hotplug	2014-01-23 16:36:52 -08:00
memory-failure.c	mm/memory-failure.c: shift page lock from head page to tail page after thp split	2014-01-23 16:36:52 -08:00
memory.c	mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE	2014-01-23 16:36:50 -08:00
mempolicy.c	mm: new_vma_page() cannot see NULL vma for hugetlb pages	2014-01-23 16:36:52 -08:00
mempool.c	mm/mempool.c: convert kmalloc_node(...GFP_ZERO...) to kzalloc_node(...)	2013-09-11 15:58:14 -07:00
migrate.c	sched/numa: fix setting of cpupid on page migration twice	2014-01-23 16:36:52 -08:00
mincore.c	mm: do_mincore() cleanup	2014-01-23 16:36:52 -08:00
mlock.c	mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE	2014-01-23 16:36:50 -08:00
mm_init.c	mm/mm_init.c: make creation of the mm_kobj happen earlier than device_initcall	2014-01-23 16:36:52 -08:00
mmap.c	mm: ignore VM_SOFTDIRTY on VMA merging	2014-01-23 16:36:53 -08:00
mmu_context.c	mm: remove old aio use_mm() comment	2013-05-07 18:38:27 -07:00
mmu_notifier.c	mm: audit/fix non-modular users of module_init in core code	2014-01-23 16:36:52 -08:00
mmzone.c	mm: numa: Change page last {nid,pid} into {cpu,pid}	2013-10-09 14:47:45 +02:00
mprotect.c	mm: numa: do not automatically migrate KSM pages	2014-01-21 16:19:48 -08:00
mremap.c	mm: revert mremap pud_free anti-fix	2013-10-16 21:35:53 -07:00
msync.c
nobootmem.c	mm/nobootmem: free_all_bootmem again	2014-01-23 16:36:52 -08:00
nommu.c	mm: add overcommit_kbytes sysctl variable	2014-01-21 16:19:44 -08:00
oom_kill.c	mm, oom: prefer thread group leaders for display purposes	2014-01-23 16:36:53 -08:00
page_alloc.c	mm: show message when updating min_free_kbytes in thp	2014-01-23 16:36:52 -08:00
page_cgroup.c	Merge branch 'akpm' (incoming from Andrew)	2014-01-21 19:05:45 -08:00
page_io.c	mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE	2014-01-23 16:36:50 -08:00
page_isolation.c	mm: memory-hotplug: enable memory hotplug to handle hugepage	2013-09-11 15:57:48 -07:00
page-writeback.c	writeback: fix negative bdi max pause	2013-10-16 21:35:53 -07:00
pagewalk.c	mm/pagewalk.c: fix walk_page_range() access of wrong PTEs	2013-10-30 14:27:03 -07:00
percpu-km.c
percpu-vm.c	mm: fix kernel-doc warnings	2012-06-20 14:39:36 -07:00
percpu.c	Merge branch 'akpm' (incoming from Andrew)	2014-01-21 19:05:45 -08:00
pgtable-generic.c	mm: fix TLB flush race between migration, and change_protection_range	2013-12-18 19:04:51 -08:00
process_vm_access.c	Fix: compat_rw_copy_check_uvector() misuse in aio, readv, writev, and security keys	2013-03-12 11:05:45 -07:00
quicklist.c	mm: delete various needless include <linux/module.h>	2011-10-31 09:20:11 -04:00
readahead.c	readahead: fix sequential read cache miss detection	2013-11-13 12:09:09 +09:00
rmap.c	mm/rmap: fix coccinelle warnings	2014-01-23 16:36:53 -08:00
shmem.c	mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE	2014-01-23 16:36:50 -08:00
slab_common.c	slab: do not panic if we fail to create memcg cache	2014-01-23 16:36:51 -08:00
slab.c	Merge branch 'slab/next' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux	2013-11-22 08:10:34 -08:00
slab.h	memcg, slab: RCU protect memcg_params for root caches	2014-01-23 16:36:51 -08:00
slob.c	mm/sl[aou]b: Move kmallocXXX functions to common code	2013-09-04 20:51:33 +03:00
slub.c	mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE	2014-01-23 16:36:50 -08:00
sparse-vmemmap.c	mm/sparse: use memblock apis for early memory allocations	2014-01-21 16:19:47 -08:00
sparse.c	mm/sparse: use memblock apis for early memory allocations	2014-01-21 16:19:47 -08:00
swap_state.c	mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE	2014-01-23 16:36:50 -08:00
swap.c	mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE	2014-01-23 16:36:50 -08:00
swapfile.c	mm/swapfile.c: do not skip lowest_bit in scan_swap_map() scan loop	2014-01-23 16:36:53 -08:00
truncate.c	truncate: drop 'oldsize' truncate_pagecache() parameter	2013-09-12 15:38:02 -07:00
util.c	mm: add overcommit_kbytes sysctl variable	2014-01-21 16:19:44 -08:00
vmalloc.c	mm/vmalloc: interchage the implementation of vmalloc_to_{pfn,page}	2014-01-21 16:19:44 -08:00
vmpressure.c	memcg: make cgroup_event deal with mem_cgroup instead of cgroup_subsys_state	2013-11-22 18:20:43 -05:00
vmscan.c	mm: vmscan: call NUMA-unaware shrinkers irrespective of nodemask	2014-01-23 16:36:52 -08:00
vmstat.c	mm: numa: return the number of base pages altered by protection changes	2013-11-13 12:09:11 +09:00
zbud.c	mm/zbud: fix some trivial typos in comments	2013-09-11 15:57:35 -07:00
zswap.c	mm/zswap.c: change params from hidden to ro	2014-01-23 16:36:50 -08:00