mirror of
https://github.com/linux-apfs/linux-apfs.git
synced 2026-05-01 15:00:59 -07:00
2f3a5272e5c16c3c10fbba06928a513f9b1e2fcd
11037 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
 Michal Hocko
|
5abf186a30 |
mm, fs: check for fatal signals in do_generic_file_read()
do_generic_file_read() can be told to perform a large request from userspace. If the system is under OOM and the reading task is the OOM victim then it has an access to memory reserves and finishing the full request can lead to the full memory depletion which is dangerous. Make sure we rather go with a short read and allow the killed task to terminate. Link: http://lkml.kernel.org/r/20170201092706.9966-3-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
 Toshi Kani
|
a96dfddbcc |
base/memory, hotplug: fix a kernel oops in show_valid_zones()
Reading a sysfs "memoryN/valid_zones" file leads to the following oops
when the first page of a range is not backed by struct page.
show_valid_zones() assumes that 'start_pfn' is always valid for
page_zone().
BUG: unable to handle kernel paging request at ffffea017a000000
IP: show_valid_zones+0x6f/0x160
This issue may happen on x86-64 systems with 64GiB or more memory since
their memory block size is bumped up to 2GiB. [1] An example of such
systems is desribed below. 0x3240000000 is only aligned by 1GiB and
this memory block starts from 0x3200000000, which is not backed by
struct page.
BIOS-e820: [mem 0x0000003240000000-0x000000603fffffff] usable
Since test_pages_in_a_zone() already checks holes, fix this issue by
extending this function to return 'valid_start' and 'valid_end' for a
given range. show_valid_zones() then proceeds with the valid range.
[1] 'Commit
|
||
|
Toshi Kani
|
deb88a2a19 |
mm/memory_hotplug.c: check start_pfn in test_pages_in_a_zone()
Patch series "fix a kernel oops when reading sysfs valid_zones", v2. A sysfs memory file is created for each 2GiB memory block on x86-64 when the system has 64GiB or more memory. [1] When the start address of a memory block is not backed by struct page, i.e. a memory range is not aligned by 2GiB, reading its 'valid_zones' attribute file leads to a kernel oops. This issue was observed on multiple x86-64 systems with more than 64GiB of memory. This patch-set fixes this issue. Patch 1 first fixes an issue in test_pages_in_a_zone(), which does not test the start section. Patch 2 then fixes the kernel oops by extending test_pages_in_a_zone() to return valid [start, end). Note for stable kernels: The memory block size change was made by commit |
||
 Kirill A. Shutemov
|
253fd0f020 |
shmem: fix sleeping from atomic context
Syzkaller fuzzer managed to trigger this:
BUG: sleeping function called from invalid context at mm/shmem.c:852
in_atomic(): 1, irqs_disabled(): 0, pid: 529, name: khugepaged
3 locks held by khugepaged/529:
#0: (shrinker_rwsem){++++..}, at: [<ffffffff818d7ef1>] shrink_slab.part.59+0x121/0xd30 mm/vmscan.c:451
#1: (&type->s_umount_key#29){++++..}, at: [<ffffffff81a63630>] trylock_super+0x20/0x100 fs/super.c:392
#2: (&(&sbinfo->shrinklist_lock)->rlock){+.+.-.}, at: [<ffffffff818fd83e>] spin_lock include/linux/spinlock.h:302 [inline]
#2: (&(&sbinfo->shrinklist_lock)->rlock){+.+.-.}, at: [<ffffffff818fd83e>] shmem_unused_huge_shrink+0x28e/0x1490 mm/shmem.c:427
CPU: 2 PID: 529 Comm: khugepaged Not tainted 4.10.0-rc5+ #201
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
shmem_undo_range+0xb20/0x2710 mm/shmem.c:852
shmem_truncate_range+0x27/0xa0 mm/shmem.c:939
shmem_evict_inode+0x35f/0xca0 mm/shmem.c:1030
evict+0x46e/0x980 fs/inode.c:553
iput_final fs/inode.c:1515 [inline]
iput+0x589/0xb20 fs/inode.c:1542
shmem_unused_huge_shrink+0xbad/0x1490 mm/shmem.c:446
shmem_unused_huge_scan+0x10c/0x170 mm/shmem.c:512
super_cache_scan+0x376/0x450 fs/super.c:106
do_shrink_slab mm/vmscan.c:378 [inline]
shrink_slab.part.59+0x543/0xd30 mm/vmscan.c:481
shrink_slab mm/vmscan.c:2592 [inline]
shrink_node+0x2c7/0x870 mm/vmscan.c:2592
shrink_zones mm/vmscan.c:2734 [inline]
do_try_to_free_pages+0x369/0xc80 mm/vmscan.c:2776
try_to_free_pages+0x3c6/0x900 mm/vmscan.c:2982
__perform_reclaim mm/page_alloc.c:3301 [inline]
__alloc_pages_direct_reclaim mm/page_alloc.c:3322 [inline]
__alloc_pages_slowpath+0xa24/0x1c30 mm/page_alloc.c:3683
__alloc_pages_nodemask+0x544/0xae0 mm/page_alloc.c:3848
__alloc_pages include/linux/gfp.h:426 [inline]
__alloc_pages_node include/linux/gfp.h:439 [inline]
khugepaged_alloc_page+0xc2/0x1b0 mm/khugepaged.c:750
collapse_huge_page+0x182/0x1fe0 mm/khugepaged.c:955
khugepaged_scan_pmd+0xfdf/0x12a0 mm/khugepaged.c:1208
khugepaged_scan_mm_slot mm/khugepaged.c:1727 [inline]
khugepaged_do_scan mm/khugepaged.c:1808 [inline]
khugepaged+0xe9b/0x1590 mm/khugepaged.c:1853
kthread+0x326/0x3f0 kernel/kthread.c:227
ret_from_fork+0x31/0x40 arch/x86/entry/entry_64.S:430
The iput() from atomic context was a bad idea: if after igrab() somebody
else calls iput() and we left with the last inode reference, our iput()
would lead to inode eviction and therefore sleeping.
This patch should fix the situation.
Link: http://lkml.kernel.org/r/20170131093141.GA15899@node.shutemov.name
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
||
 Peter Zijlstra
|
4f40c6e562 |
kasan: respect /proc/sys/kernel/traceoff_on_warning
After much waiting I finally reproduced a KASAN issue, only to find my trace-buffer empty of useful information because it got spooled out :/ Make kasan_report honour the /proc/sys/kernel/traceoff_on_warning interface. Link: http://lkml.kernel.org/r/20170125164106.3514-1-aryabinin@virtuozzo.com Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Acked-by: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
 Dan Streetman
|
d7b028f56a |
zswap: disable changing params if init fails
Add zswap_init_failed bool that prevents changing any of the module
params, if init_zswap() fails, and set zswap_enabled to false. Change
'enabled' param to a callback, and check zswap_init_failed before
allowing any change to 'enabled', 'zpool', or 'compressor' params.
Any driver that is built-in to the kernel will not be unloaded if its
init function returns error, and its module params remain accessible for
users to change via sysfs. Since zswap uses param callbacks, which
assume that zswap has been initialized, changing the zswap params after
a failed initialization will result in WARNING due to the param
callbacks expecting a pool to already exist. This prevents that by
immediately exiting any of the param callbacks if initialization failed.
This was reported here:
https://marc.info/?l=linux-mm&m=147004228125528&w=4
And fixes this WARNING:
[ 429.723476] WARNING: CPU: 0 PID: 5140 at mm/zswap.c:503 __zswap_pool_current+0x56/0x60
The warning is just noise, and not serious. However, when init fails,
zswap frees all its percpu dstmem pages and its kmem cache. The kmem
cache might be serious, if kmem_cache_alloc(NULL, gfp) has problems; but
the percpu dstmem pages are definitely a problem, as they're used as
temporary buffer for compressed pages before copying into place in the
zpool.
If the user does get zswap enabled after an init failure, then zswap
will likely Oops on the first page it tries to compress (or worse, start
corrupting memory).
Fixes:
|
||
 Vlastimil Babka
|
e47483bca2 |
mm, page_alloc: fix premature OOM when racing with cpuset mems update
Ganapatrao Kulkarni reported that the LTP test cpuset01 in stress mode triggers OOM killer in few seconds, despite lots of free memory. The test attempts to repeatedly fault in memory in one process in a cpuset, while changing allowed nodes of the cpuset between 0 and 1 in another process. The problem comes from insufficient protection against cpuset changes, which can cause get_page_from_freelist() to consider all zones as non-eligible due to nodemask and/or current->mems_allowed. This was masked in the past by sufficient retries, but since commit |
||
|
Vlastimil Babka
|
5ce9bfef1d |
mm, page_alloc: move cpuset seqcount checking to slowpath
This is a preparation for the following patch to make review simpler. While the primary motivation is a bug fix, this also simplifies the fast path, although the moved code is only enabled when cpusets are in use. Link: http://lkml.kernel.org/r/20170120103843.24587-4-vbabka@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com> Cc: Ganapatrao Kulkarni <gpkulkarni@gmail.com> Cc: Michal Hocko <mhocko@suse.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Vlastimil Babka
|
16096c25bf |
mm, page_alloc: fix fast-path race with cpuset update or removal
Ganapatrao Kulkarni reported that the LTP test cpuset01 in stress mode
triggers OOM killer in few seconds, despite lots of free memory. The
test attempts to repeatedly fault in memory in one process in a cpuset,
while changing allowed nodes of the cpuset between 0 and 1 in another
process.
One possible cause is that in the fast path we find the preferred
zoneref according to current mems_allowed, so that it points to the
middle of the zonelist, skipping e.g. zones of node 1 completely. If
the mems_allowed is updated to contain only node 1, we never reach it in
the zonelist, and trigger OOM before checking the cpuset_mems_cookie.
This patch fixes the particular case by redoing the preferred zoneref
search if we switch back to the original nodemask. The condition is
also slightly changed so that when the last non-root cpuset is removed,
we don't miss it.
Note that this is not a full fix, and more patches will follow.
Link: http://lkml.kernel.org/r/20170120103843.24587-3-vbabka@suse.cz
Fixes:
|
||
|
Vlastimil Babka
|
ea57485af8 |
mm, page_alloc: fix check for NULL preferred_zone
Patch series "fix premature OOM regression in 4.7+ due to cpuset races". This is v2 of my attempt to fix the recent report based on LTP cpuset stress test [1]. The intention is to go to stable 4.9 LTSS with this, as triggering repeated OOMs is not nice. That's why the patches try to be not too intrusive. Unfortunately why investigating I found that modifying the testcase to use per-VMA policies instead of per-task policies will bring the OOM's back, but that seems to be much older and harder to fix problem. I have posted a RFC [2] but I believe that fixing the recent regressions has a higher priority. Longer-term we might try to think how to fix the cpuset mess in a better and less error prone way. I was for example very surprised to learn, that cpuset updates change not only task->mems_allowed, but also nodemask of mempolicies. Until now I expected the parameter to alloc_pages_nodemask() to be stable. I wonder why do we then treat cpusets specially in get_page_from_freelist() and distinguish HARDWALL etc, when there's unconditional intersection between mempolicy and cpuset. I would expect the nodemask adjustment for saving overhead in g_p_f(), but that clearly doesn't happen in the current form. So we have both crazy complexity and overhead, AFAICS. [1] https://lkml.kernel.org/r/CAFpQJXUq-JuEP=QPidy4p_=FN0rkH5Z-kfB4qBvsf6jMS87Edg@mail.gmail.com [2] https://lkml.kernel.org/r/7c459f26-13a6-a817-e508-b65b903a8378@suse.cz This patch (of 4): Since commit |
||
|
Vlastimil Babka
|
d51e9894d2 |
mm/mempolicy.c: do not put mempolicy before using its nodemask
Since commit |
||
 David Rientjes
|
3674534b77 |
mm, memcg: do not retry precharge charges
When memory.move_charge_at_immigrate is enabled and precharges are
depleted during move, mem_cgroup_move_charge_pte_range() will attempt to
increase the size of the precharge.
Prevent precharges from ever looping by setting __GFP_NORETRY. This was
probably the intention of the GFP_KERNEL & ~__GFP_NORETRY, which is
pointless as written.
Fixes:
|
||
 Lucas Stach
|
424f6c4818 |
mm: alloc_contig: re-allow CMA to compact FS pages
Commit |
||
 Daniel Thompson
|
aa2efd5ea4 |
mm/slub.c: trace free objects at KERN_INFO
Currently when trace is enabled (e.g. slub_debug=T,kmalloc-128 ) the trace messages are mostly output at KERN_INFO. However the trace code also calls print_section() to hexdump the head of a free object. This is hard coded to use KERN_ERR, meaning the console is deluged with trace messages even if we've asked for quiet. Fix this the obvious way but adding a level parameter to print_section(), allowing calls from the trace code to use the same trace level as other trace messages. Link: http://lkml.kernel.org/r/20170113154850.518-1-daniel.thompson@linaro.org Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Acked-by: Christoph Lameter <cl@linux.com> Acked-by: David Rientjes <rientjes@google.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
 Keno Fischer
|
8310d48b12 |
mm/huge_memory.c: respect FOLL_FORCE/FOLL_COW for thp
In commit
|
||
 Yasuaki Ishimatsu
|
8a1f780e7f |
memory_hotplug: make zone_can_shift() return a boolean value
online_{kernel|movable} is used to change the memory zone to
ZONE_{NORMAL|MOVABLE} and online the memory.
To check that memory zone can be changed, zone_can_shift() is used.
Currently the function returns minus integer value, plus integer
value and 0. When the function returns minus or plus integer value,
it means that the memory zone can be changed to ZONE_{NORNAL|MOVABLE}.
But when the function returns 0, there are two meanings.
One of the meanings is that the memory zone does not need to be changed.
For example, when memory is in ZONE_NORMAL and onlined by online_kernel
the memory zone does not need to be changed.
Another meaning is that the memory zone cannot be changed. When memory
is in ZONE_NORMAL and onlined by online_movable, the memory zone may
not be changed to ZONE_MOVALBE due to memory online limitation(see
Documentation/memory-hotplug.txt). In this case, memory must not be
onlined.
The patch changes the return type of zone_can_shift() so that memory
online operation fails when memory zone cannot be changed as follows:
Before applying patch:
# grep -A 35 "Node 2" /proc/zoneinfo
Node 2, zone Normal
<snip>
node_scanned 0
spanned 8388608
present 7864320
managed 7864320
# echo online_movable > memory4097/state
# grep -A 35 "Node 2" /proc/zoneinfo
Node 2, zone Normal
<snip>
node_scanned 0
spanned 8388608
present 8388608
managed 8388608
online_movable operation succeeded. But memory is onlined as
ZONE_NORMAL, not ZONE_MOVABLE.
After applying patch:
# grep -A 35 "Node 2" /proc/zoneinfo
Node 2, zone Normal
<snip>
node_scanned 0
spanned 8388608
present 7864320
managed 7864320
# echo online_movable > memory4097/state
bash: echo: write error: Invalid argument
# grep -A 35 "Node 2" /proc/zoneinfo
Node 2, zone Normal
<snip>
node_scanned 0
spanned 8388608
present 7864320
managed 7864320
online_movable operation failed because of failure of changing
the memory zone from ZONE_NORMAL to ZONE_MOVABLE
Fixes:
|
||
 Mike Kravetz
|
e5bbc8a6c9 |
mm/hugetlb.c: fix reservation race when freeing surplus pages
return_unused_surplus_pages() decrements the global reservation count, and frees any unused surplus pages that were backing the reservation. Commit |
||
 John Sperbeck
|
c4e490cf14 |
mm/slab.c: fix SLAB freelist randomization duplicate entries
This patch fixes a bug in the freelist randomization code. When a high
random number is used, the freelist will contain duplicate entries. It
will result in different allocations sharing the same chunk.
It will result in odd behaviours and crashes. It should be uncommon but
it depends on the machines. We saw it happening more often on some
machines (every few hours of running tests).
Fixes:
|
||
 Minchan Kim
|
f05714293a |
mm: support anonymous stable page
During developemnt for zram-swap asynchronous writeback, I found strange
corruption of compressed page, resulting in:
Modules linked in: zram(E)
CPU: 3 PID: 1520 Comm: zramd-1 Tainted: G E 4.8.0-mm1-00320-ge0d4894c9c38-dirty #3274
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
task: ffff88007620b840 task.stack: ffff880078090000
RIP: set_freeobj.part.43+0x1c/0x1f
RSP: 0018:ffff880078093ca8 EFLAGS: 00010246
RAX: 0000000000000018 RBX: ffff880076798d88 RCX: ffffffff81c408c8
RDX: 0000000000000018 RSI: 0000000000000000 RDI: 0000000000000246
RBP: ffff880078093cb0 R08: 0000000000000000 R09: 0000000000000000
R10: ffff88005bc43030 R11: 0000000000001df3 R12: ffff880076798d88
R13: 000000000005bc43 R14: ffff88007819d1b8 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff88007e380000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc934048f20 CR3: 0000000077b01000 CR4: 00000000000406e0
Call Trace:
obj_malloc+0x22b/0x260
zs_malloc+0x1e4/0x580
zram_bvec_rw+0x4cd/0x830 [zram]
page_requests_rw+0x9c/0x130 [zram]
zram_thread+0xe6/0x173 [zram]
kthread+0xca/0xe0
ret_from_fork+0x25/0x30
With investigation, it reveals currently stable page doesn't support
anonymous page. IOW, reuse_swap_page can reuse the page without waiting
writeback completion so it can overwrite page zram is compressing.
Unfortunately, zram has used per-cpu stream feature from v4.7.
It aims for increasing cache hit ratio of scratch buffer for
compressing. Downside of that approach is that zram should ask
memory space for compressed page in per-cpu context which requires
stricted gfp flag which could be failed. If so, it retries to
allocate memory space out of per-cpu context so it could get memory
this time and compress the data again, copies it to the memory space.
In this scenario, zram assumes the data should never be changed
but it is not true unless stable page supports. So, If the data is
changed under us, zram can make buffer overrun because second
compression size could be bigger than one we got in previous trial
and blindly, copy bigger size object to smaller buffer which is
buffer overrun. The overrun breaks zsmalloc free object chaining
so system goes crash like above.
I think below is same problem.
https://bugzilla.suse.com/show_bug.cgi?id=997574
Unfortunately, reuse_swap_page should be atomic so that we cannot wait on
writeback in there so the approach in this patch is simply return false if
we found it needs stable page. Although it increases memory footprint
temporarily, it happens rarely and it should be reclaimed easily althoug
it happened. Also, It would be better than waiting of IO completion,
which is critial path for application latency.
Fixes:
|
||
 Alexander Duyck
|
2976db8018 |
mm: rename __page_frag functions to __page_frag_cache, drop order from drain
This patch does two things. First it goes through and renames the __page_frag prefixed functions to __page_frag_cache so that we can be clear that we are draining or refilling the cache, not the frags themselves. Second we drop the order parameter from __page_frag_cache_drain since we don't actually need to pass it since all fragments are either order 0 or must be a compound page. Link: http://lkml.kernel.org/r/20170104023954.13451.5678.stgit@localhost.localdomain Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Alexander Duyck
|
8c2dd3e4a4 |
mm: rename __alloc_page_frag to page_frag_alloc and __free_page_frag to page_frag_free
Patch series "Page fragment updates", v4. This patch series takes care of a few cleanups for the page fragments API. First we do some renames so that things are much more consistent. First we move the page_frag_ portion of the name to the front of the functions names. Secondly we split out the cache specific functions from the other page fragment functions by adding the word "cache" to the name. Finally I added a bit of documentation that will hopefully help to explain some of this. I plan to revisit this later as we get things more ironed out in the near future with the changes planned for the DMA setup to support eXpress Data Path. This patch (of 3): This patch renames the page frag functions to be more consistent with other APIs. Specifically we place the name page_frag first in the name and then have either an alloc or free call name that we append as the suffix. This makes it a bit clearer in terms of naming. In addition we drop the leading double underscores since we are technically no longer a backing interface and instead the front end that is called from the networking APIs. Link: http://lkml.kernel.org/r/20170104023854.13451.67390.stgit@localhost.localdomain Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Michal Hocko
|
b4536f0c82 |
mm, memcg: fix the active list aging for lowmem requests when memcg is enabled
Nils Holland and Klaus Ethgen have reported unexpected OOM killer invocations with 32b kernel starting with 4.8 kernels kworker/u4:5 invoked oom-killer: gfp_mask=0x2400840(GFP_NOFS|__GFP_NOFAIL), nodemask=0, order=0, oom_score_adj=0 kworker/u4:5 cpuset=/ mems_allowed=0 CPU: 1 PID: 2603 Comm: kworker/u4:5 Not tainted 4.9.0-gentoo #2 [...] Mem-Info: active_anon:58685 inactive_anon:90 isolated_anon:0 active_file:274324 inactive_file:281962 isolated_file:0 unevictable:0 dirty:649 writeback:0 unstable:0 slab_reclaimable:40662 slab_unreclaimable:17754 mapped:7382 shmem:202 pagetables:351 bounce:0 free:206736 free_pcp:332 free_cma:0 Node 0 active_anon:234740kB inactive_anon:360kB active_file:1097296kB inactive_file:1127848kB unevictable:0kB isolated(anon):0kB isolated(file):0kB mapped:29528kB dirty:2596kB writeback:0kB shmem:0kB shmem_thp: 0kB shmem_pmdmapped: 184320kB anon_thp: 808kB writeback_tmp:0kB unstable:0kB pages_scanned:0 all_unreclaimable? no DMA free:3952kB min:788kB low:984kB high:1180kB active_anon:0kB inactive_anon:0kB active_file:7316kB inactive_file:0kB unevictable:0kB writepending:96kB present:15992kB managed:15916kB mlocked:0kB slab_reclaimable:3200kB slab_unreclaimable:1408kB kernel_stack:0kB pagetables:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB lowmem_reserve[]: 0 813 3474 3474 Normal free:41332kB min:41368kB low:51708kB high:62048kB active_anon:0kB inactive_anon:0kB active_file:532748kB inactive_file:44kB unevictable:0kB writepending:24kB present:897016kB managed:836248kB mlocked:0kB slab_reclaimable:159448kB slab_unreclaimable:69608kB kernel_stack:1112kB pagetables:1404kB bounce:0kB free_pcp:528kB local_pcp:340kB free_cma:0kB lowmem_reserve[]: 0 0 21292 21292 HighMem free:781660kB min:512kB low:34356kB high:68200kB active_anon:234740kB inactive_anon:360kB active_file:557232kB inactive_file:1127804kB unevictable:0kB writepending:2592kB present:2725384kB managed:2725384kB mlocked:0kB slab_reclaimable:0kB slab_unreclaimable:0kB kernel_stack:0kB pagetables:0kB bounce:0kB free_pcp:800kB local_pcp:608kB free_cma:0kB the oom killer is clearly pre-mature because there there is still a lot of page cache in the zone Normal which should satisfy this lowmem request. Further debugging has shown that the reclaim cannot make any forward progress because the page cache is hidden in the active list which doesn't get rotated because inactive_list_is_low is not memcg aware. The code simply subtracts per-zone highmem counters from the respective memcg's lru sizes which doesn't make any sense. We can simply end up always seeing the resulting active and inactive counts 0 and return false. This issue is not limited to 32b kernels but in practice the effect on systems without CONFIG_HIGHMEM would be much harder to notice because we do not invoke the OOM killer for allocations requests targeting < ZONE_NORMAL. Fix the issue by tracking per zone lru page counts in mem_cgroup_per_node and subtract per-memcg highmem counts when memcg is enabled. Introduce helper lruvec_zone_lru_size which redirects to either zone counters or mem_cgroup_get_zone_lru_size when appropriate. We are losing empty LRU but non-zero lru size detection introduced by |
||
 Ard Biesheuvel
|
f073bdc517 |
mm: don't dereference struct page fields of invalid pages
The VM_BUG_ON() check in move_freepages() checks whether the node id of a page matches the node id of its zone. However, it does this before having checked whether the struct page pointer refers to a valid struct page to begin with. This is guaranteed in most cases, but may not be the case if CONFIG_HOLES_IN_ZONE=y. So reorder the VM_BUG_ON() with the pfn_valid_within() check. Link: http://lkml.kernel.org/r/1481706707-6211-2-git-send-email-ard.biesheuvel@linaro.org Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Hanjun Guo <hanjun.guo@linaro.org> Cc: Yisheng Xie <xieyisheng1@huawei.com> Cc: Robert Richter <rrichter@cavium.com> Cc: James Morse <james.morse@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Minchan Kim
|
20f664aabe |
mm: pmd dirty emulation in page fault handler
Andreas reported [1] made a test in jemalloc hang in THP mode in arm64: http://lkml.kernel.org/r/mvmmvfy37g1.fsf@hawking.suse.de The problem is currently page fault handler doesn't supports dirty bit emulation of pmd for non-HW dirty-bit architecture so that application stucks until VM marked the pmd dirty. How the emulation work depends on the architecture. In case of arm64, when it set up pte firstly, it sets pte PTE_RDONLY to get a chance to mark the pte dirty via triggering page fault when store access happens. Once the page fault occurs, VM marks the pmd dirty and arch code for setting pmd will clear PTE_RDONLY for application to proceed. IOW, if VM doesn't mark the pmd dirty, application hangs forever by repeated fault(i.e., store op but the pmd is PTE_RDONLY). This patch enables pmd dirty-bit emulation for those architectures. [1] |
||
|
Michal Hocko
|
41b6167e8f |
mm: get rid of __GFP_OTHER_NODE
The flag was introduced by commit
|