There are many BUG_ON in zsmalloc.c which is not recommened so change
them as alternatives.
Normal rule is as follows:
1. avoid BUG_ON if possible. Instead, use VM_BUG_ON or VM_BUG_ON_PAGE
2. use VM_BUG_ON_PAGE if we need to see struct page's fields
3. use those assertion in primitive functions so higher functions can
rely on the assertion in the primitive function.
4. Don't use assertion if following instruction can trigger Oops
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: 830e4bc5baa9fda5d45257e9a3dbb3555c6c180e
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Change-Id: Ia4b15fb09ad5398165781861952d075665c8b8e9
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
Clean up function parameter "struct page". Many functions of zsmalloc
expect that page paramter is "first_page" so use "first_page" rather
than "page" for code readability.
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: a42094676f076534bf4998625456fe0bb99c1f1e
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Change-Id: I68c0a37a1fd5c8a9f34c7e7a0d2a580c1720685d
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
Add a new column to pool stats, which will tell how many pages ideally
can be freed by class compaction, so it will be easier to analyze
zsmalloc fragmentation.
At the moment, we have only numbers of FULL and ALMOST_EMPTY classes,
but they don't tell us how badly the class is fragmented internally.
The new /sys/kernel/debug/zsmalloc/zramX/classes output look as follows:
class size almost_full almost_empty obj_allocated obj_used pages_used pages_per_zspage freeable
[..]
12 224 0 2 146 5 8 4 4
13 240 0 0 0 0 0 1 0
14 256 1 13 1840 1672 115 1 10
15 272 0 0 0 0 0 1 0
[..]
49 816 0 3 745 735 149 1 2
51 848 3 4 361 306 76 4 8
52 864 12 14 378 268 81 3 21
54 896 1 12 117 57 26 2 12
57 944 0 0 0 0 0 3 0
[..]
Total 26 131 12709 10994 1071 134
For example, from this particular output we can easily conclude that
class-896 is heavily fragmented -- it occupies 26 pages, 12 can be freed
by compaction.
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: 1120ed5483941d9cd2cf52cb9644a4311dbd1011
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Change-Id: Ib3cf57a59c3c3ec469f43f594a1b20514ea8e452
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
When unmapping a huge class page in zs_unmap_object, the page will be
unmapped by kmap_atomic. the "!area->huge" branch in __zs_unmap_object
is alway true, and no code set "area->huge" now, so we can drop it.
Signed-off-by: YiPing Xu <xuyiping@huawei.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: a82cbf07131b56e7e51fbb008b82ef769af08790
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Change-Id: I332dc03f886d1e6547b0b59914046a7924405d1b
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
Reoder the pages_per_zspage field in struct size_class which can
eliminate the 4 bytes hole between it and stats field.
Signed-off-by: Weijie Yang <weijie.yang@samsung.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: 7dfa4612204b511c934ca2a0e4f306f9981bd9aa
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Change-Id: I82fdd68951448d78540e61f70d8d0123604d7e28
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
Now, VM has a feature to migrate non-lru movable pages so balloon
doesn't need custom migration hooks in migrate.c and compaction.c.
Instead, this patch implements the page->mapping->a_ops->
{isolate|migrate|putback} functions.
With that, we could remove hooks for ballooning in general migration
functions and make balloon compaction simple.
[akpm@linux-foundation.org: compaction.h requires that the includer first include node.h]
Link: http://lkml.kernel.org/r/1464736881-24886-4-git-send-email-minchan@kernel.org
Signed-off-by: Gioh Kim <gi-oh.kim@profitbricks.com>
Signed-off-by: Minchan Kim <minchan@kernel.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Rafael Aquini <aquini@redhat.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: b1123ea6d3b3da25af5c8a9d843bd07ab63213f4
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Change-Id: Ibf5bc7ffcbfd31e01946729dc5366baa79d7cf5e
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
We have allowed migration for only LRU pages until now and it was enough
to make high-order pages. But recently, embedded system(e.g., webOS,
android) uses lots of non-movable pages(e.g., zram, GPU memory) so we
have seen several reports about troubles of small high-order allocation.
For fixing the problem, there were several efforts (e,g,. enhance
compaction algorithm, SLUB fallback to 0-order page, reserved memory,
vmalloc and so on) but if there are lots of non-movable pages in system,
their solutions are void in the long run.
So, this patch is to support facility to change non-movable pages with
movable. For the feature, this patch introduces functions related to
migration to address_space_operations as well as some page flags.
If a driver want to make own pages movable, it should define three
functions which are function pointers of struct
address_space_operations.
1. bool (*isolate_page) (struct page *page, isolate_mode_t mode);
What VM expects on isolate_page function of driver is to return *true*
if driver isolates page successfully. On returing true, VM marks the
page as PG_isolated so concurrent isolation in several CPUs skip the
page for isolation. If a driver cannot isolate the page, it should
return *false*.
Once page is successfully isolated, VM uses page.lru fields so driver
shouldn't expect to preserve values in that fields.
2. int (*migratepage) (struct address_space *mapping,
struct page *newpage, struct page *oldpage, enum migrate_mode);
After isolation, VM calls migratepage of driver with isolated page. The
function of migratepage is to move content of the old page to new page
and set up fields of struct page newpage. Keep in mind that you should
indicate to the VM the oldpage is no longer movable via
__ClearPageMovable() under page_lock if you migrated the oldpage
successfully and returns 0. If driver cannot migrate the page at the
moment, driver can return -EAGAIN. On -EAGAIN, VM will retry page
migration in a short time because VM interprets -EAGAIN as "temporal
migration failure". On returning any error except -EAGAIN, VM will give
up the page migration without retrying in this time.
Driver shouldn't touch page.lru field VM using in the functions.
3. void (*putback_page)(struct page *);
If migration fails on isolated page, VM should return the isolated page
to the driver so VM calls driver's putback_page with migration failed
page. In this function, driver should put the isolated page back to the
own data structure.
4. non-lru movable page flags
There are two page flags for supporting non-lru movable page.
* PG_movable
Driver should use the below function to make page movable under
page_lock.
void __SetPageMovable(struct page *page, struct address_space *mapping)
It needs argument of address_space for registering migration family
functions which will be called by VM. Exactly speaking, PG_movable is
not a real flag of struct page. Rather than, VM reuses page->mapping's
lower bits to represent it.
#define PAGE_MAPPING_MOVABLE 0x2
page->mapping = page->mapping | PAGE_MAPPING_MOVABLE;
so driver shouldn't access page->mapping directly. Instead, driver
should use page_mapping which mask off the low two bits of page->mapping
so it can get right struct address_space.
For testing of non-lru movable page, VM supports __PageMovable function.
However, it doesn't guarantee to identify non-lru movable page because
page->mapping field is unified with other variables in struct page. As
well, if driver releases the page after isolation by VM, page->mapping
doesn't have stable value although it has PAGE_MAPPING_MOVABLE (Look at
__ClearPageMovable). But __PageMovable is cheap to catch whether page
is LRU or non-lru movable once the page has been isolated. Because LRU
pages never can have PAGE_MAPPING_MOVABLE in page->mapping. It is also
good for just peeking to test non-lru movable pages before more
expensive checking with lock_page in pfn scanning to select victim.
For guaranteeing non-lru movable page, VM provides PageMovable function.
Unlike __PageMovable, PageMovable functions validates page->mapping and
mapping->a_ops->isolate_page under lock_page. The lock_page prevents
sudden destroying of page->mapping.
Driver using __SetPageMovable should clear the flag via
__ClearMovablePage under page_lock before the releasing the page.
* PG_isolated
To prevent concurrent isolation among several CPUs, VM marks isolated
page as PG_isolated under lock_page. So if a CPU encounters PG_isolated
non-lru movable page, it can skip it. Driver doesn't need to manipulate
the flag because VM will set/clear it automatically. Keep in mind that
if driver sees PG_isolated page, it means the page have been isolated by
VM so it shouldn't touch page.lru field. PG_isolated is alias with
PG_reclaim flag so driver shouldn't use the flag for own purpose.
[opensource.ganesh@gmail.com: mm/compaction: remove local variable is_lru]
Link: http://lkml.kernel.org/r/20160618014841.GA7422@leo-test
Link: http://lkml.kernel.org/r/1464736881-24886-3-git-send-email-minchan@kernel.org
Signed-off-by: Gioh Kim <gi-oh.kim@profitbricks.com>
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Ganesh Mahendran <opensource.ganesh@gmail.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rafael Aquini <aquini@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: John Einar Reitan <john.reitan@foss.arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: bda807d4445414e8e77da704f116bb0880fe0c76
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Change-Id: I03380d927fed84c7464bd5f7c4405bef6b265b69
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
Recently, I got many reports about perfermance degradation in embedded
system(Android mobile phone, webOS TV and so on) and easy fork fail.
The problem was fragmentation caused by zram and GPU driver mainly.
With memory pressure, their pages were spread out all of pageblock and
it cannot be migrated with current compaction algorithm which supports
only LRU pages. In the end, compaction cannot work well so reclaimer
shrinks all of working set pages. It made system very slow and even to
fail to fork easily which requires order-[2 or 3] allocations.
Other pain point is that they cannot use CMA memory space so when OOM
kill happens, I can see many free pages in CMA area, which is not memory
efficient. In our product which has big CMA memory, it reclaims zones
too exccessively to allocate GPU and zram page although there are lots
of free space in CMA so system becomes very slow easily.
To solve these problem, this patch tries to add facility to migrate
non-lru pages via introducing new functions and page flags to help
migration.
struct address_space_operations {
..
..
bool (*isolate_page)(struct page *, isolate_mode_t);
void (*putback_page)(struct page *);
..
}
new page flags
PG_movable
PG_isolated
For details, please read description in "mm: migrate: support non-lru
movable page migration".
Originally, Gioh Kim had tried to support this feature but he moved so I
took over the work. I took many code from his work and changed a little
bit and Konstantin Khlebnikov helped Gioh a lot so he should deserve to
have many credit, too.
And I should mention Chulmin who have tested this patchset heavily so I
can find many bugs from him. :)
Thanks, Gioh, Konstantin and Chulmin!
This patchset consists of five parts.
1. clean up migration
mm: use put_page to free page instead of putback_lru_page
2. add non-lru page migration feature
mm: migrate: support non-lru movable page migration
3. rework KVM memory-ballooning
mm: balloon: use general non-lru movable page feature
4. zsmalloc refactoring for preparing page migration
zsmalloc: keep max_object in size_class
zsmalloc: use bit_spin_lock
zsmalloc: use accessor
zsmalloc: factor page chain functionality out
zsmalloc: introduce zspage structure
zsmalloc: separate free_zspage from putback_zspage
zsmalloc: use freeobj for index
5. zsmalloc page migration
zsmalloc: page migration support
zram: use __GFP_MOVABLE for memory allocation
This patch (of 12):
Procedure of page migration is as follows:
First of all, it should isolate a page from LRU and try to migrate the
page. If it is successful, it releases the page for freeing.
Otherwise, it should put the page back to LRU list.
For LRU pages, we have used putback_lru_page for both freeing and
putback to LRU list. It's okay because put_page is aware of LRU list so
if it releases last refcount of the page, it removes the page from LRU
list. However, It makes unnecessary operations (e.g., lru_cache_add,
pagevec and flags operations. It would be not significant but no worth
to do) and harder to support new non-lru page migration because put_page
isn't aware of non-lru page's data structure.
To solve the problem, we can add new hook in put_page with PageMovable
flags check but it can increase overhead in hot path and needs new
locking scheme to stabilize the flag check with put_page.
So, this patch cleans it up to divide two semantic(ie, put and putback).
If migration is successful, use put_page instead of putback_lru_page and
use putback_lru_page only on failure. That makes code more readable and
doesn't add overhead in put_page.
Comment from Vlastimil
"Yeah, and compaction (perhaps also other migration users) has to drain
the lru pvec... Getting rid of this stuff is worth even by itself."
Link: http://lkml.kernel.org/r/1464736881-24886-2-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: c6c919eb90e021fbcfcbfa9dd3d55930cdbb67f9
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Change-Id: I2c00623996f8017b9c84ed12fcc4d85290a1712c
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
While testing the kcompactd in my platform 3G MEM only DMA ZONE. I
found the kcompactd never wakeup. It seems the zoneindex has already
minus 1 before. So the traverse here should be <=.
It fixes a regression where kswapd could previously compact, but
kcompactd not. Not a crash fix though.
[akpm@linux-foundation.org: fix kcompactd_do_work() as well, per Hugh]
Link: http://lkml.kernel.org/r/1463659121-84124-1-git-send-email-puck.chen@hisilicon.com
Fixes: accf62422b3a ("mm, kswapd: replace kswapd compaction with waking up kcompactd")
Signed-off-by: Chen Feng <puck.chen@hisilicon.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Zhuangluan Su <suzhuangluan@hisilicon.com>
Cc: Yiping Xu <xuyiping@hisilicon.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: 6cd9dc3e75078ef646076fa63adfb9b85ced0b66
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Change-Id: Id5d2fe71ab7e62b0c063b9ba27b3b112447d1fdc
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
Assume memory47 is the last online block left in node1. This will hang:
# echo offline > /sys/devices/system/node/node1/memory47/state
After a couple of minutes, the following pops up in dmesg:
INFO: task bash:957 blocked for more than 120 seconds.
Not tainted 4.6.0-rc6+ #6
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
bash D ffff8800b7adbaf8 0 957 951 0x00000000
Call Trace:
schedule+0x35/0x80
schedule_timeout+0x1ac/0x270
wait_for_completion+0xe1/0x120
kthread_stop+0x4f/0x110
kcompactd_stop+0x26/0x40
__offline_pages.constprop.28+0x7e6/0x840
offline_pages+0x11/0x20
memory_block_action+0x73/0x1d0
memory_subsys_offline+0x47/0x60
device_offline+0x86/0xb0
store_mem_state+0xda/0xf0
dev_attr_store+0x18/0x30
sysfs_kf_write+0x37/0x40
kernfs_fop_write+0x11d/0x170
__vfs_write+0x37/0x120
vfs_write+0xa9/0x1a0
SyS_write+0x55/0xc0
entry_SYSCALL_64_fastpath+0x1a/0xa4
kcompactd is waiting for kcompactd_max_order > 0 when it's woken up to
actually exit. Check kthread_should_stop() to break out of the wait.
Fixes: 698b1b306 ("mm, compaction: introduce kcompactd").
Reported-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Tested-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: David Rientjes <rientjes@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: 172400c69cb0d0d684b7cd75ac75872b3d7c61a1
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Change-Id: Ia90162cd5fe4cd502efc6bde3bf70cd227f58899
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
When kswapd goes to sleep it checks if the node is balanced and at first
it sleeps only for HZ/10 time, then rechecks if the node is still
balanced and nobody has woken it during the initial sleep. Only then it
goes fully sleep until an allocation slowpath wakes it up again.
For higher-order allocations, waking up kcompactd is done only before
the full sleep. This turns out to be an issue in case another
high-order allocation fails during the initial sleep. It will wake
kswapd up, however kswapd considers the zone balanced from the order-0
perspective, and will just quickly try to sleep again. So if there's a
longer stream of high-order allocations hitting the slowpath and waking
up kswapd, it might never actually wake up kcompactd, which may be
considered a regression from kswapd-based compaction. In the worst
case, it might be that a single allocation that cannot direct
reclaim/compact itself is waking kswapd in the retry loop and preventing
kcompactd from being woken up and unblocking it.
This patch makes sure kcompactd is woken up in such situations by simply
moving the wakeup before the short initial sleep. More efficient
solution would be to wake kcompactd immediately instead of kswapd if the
node is already order-0 balanced, but in that case we should also move
reset_isolation_suitable() call to kcompactd so it's not adding to the
allocator's latency. Since it's late in the 4.6 cycle, let's go with
the simpler change for now.
Fixes: accf62422b3a ("mm, kswapd: replace kswapd compaction with waking up kcompactd")
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: David Rientjes <rientjes@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: fd901c95388b3bd5a6f749ed1d677a672b992298
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Change-Id: I6ecee84788d40a327d33c1ed3655172f4f20f06b
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
Similarly to direct reclaim/compaction, kswapd attempts to combine
reclaim and compaction to attempt making memory allocation of given
order available.
The details differ from direct reclaim e.g. in having high watermark as
a goal. The code involved in kswapd's reclaim/compaction decisions has
evolved to be quite complex.
Testing reveals that it doesn't actually work in at least one scenario,
and closer inspection suggests that it could be greatly simplified
without compromising on the goal (make high-order page available) or
efficiency (don't reclaim too much). The simplification relieas of
doing all compaction in kcompactd, which is simply woken up when high
watermarks are reached by kswapd's reclaim.
The scenario where kswapd compaction doesn't work was found with mmtests
test stress-highalloc configured to attempt order-9 allocations without
direct reclaim, just waking up kswapd. There was no compaction attempt
from kswapd during the whole test. Some added instrumentation shows
what happens:
- balance_pgdat() sets end_zone to Normal, as it's not balanced
- reclaim is attempted on DMA zone, which sets nr_attempted to 99, but
it cannot reclaim anything, so sc.nr_reclaimed is 0
- for zones DMA32 and Normal, kswapd_shrink_zone uses testorder=0, so
it merely checks if high watermarks were reached for base pages.
This is true, so no reclaim is attempted. For DMA, testorder=0
wasn't used, as compaction_suitable() returned COMPACT_SKIPPED
- even though the pgdat_needs_compaction flag wasn't set to false, no
compaction happens due to the condition sc.nr_reclaimed >
nr_attempted being false (as 0 < 99)
- priority-- due to nr_reclaimed being 0, repeat until priority reaches
0 pgdat_balanced() is false as only the small zone DMA appears
balanced (curiously in that check, watermark appears OK and
compaction_suitable() returns COMPACT_PARTIAL, because a lower
classzone_idx is used there)
Now, even if it was decided that reclaim shouldn't be attempted on the
DMA zone, the scenario would be the same, as (sc.nr_reclaimed=0 >
nr_attempted=0) is also false. The condition really should use >= as
the comment suggests. Then there is a mismatch in the check for setting
pgdat_needs_compaction to false using low watermark, while the rest uses
high watermark, and who knows what other subtlety. Hopefully this
demonstrates that this is unsustainable.
Luckily we can simplify this a lot. The reclaim/compaction decisions
make sense for direct reclaim scenario, but in kswapd, our primary goal
is to reach high watermark in order-0 pages. Afterwards we can attempt
compaction just once. Unlike direct reclaim, we don't reclaim extra
pages (over the high watermark), the current code already disallows it
for good reasons.
After this patch, we simply wake up kcompactd to process the pgdat,
after we have either succeeded or failed to reach the high watermarks in
kswapd, which goes to sleep. We pass kswapd's order and classzone_idx,
so kcompactd can apply the same criteria to determine which zones are
worth compacting. Note that we use the classzone_idx from
wakeup_kswapd(), not balanced_classzone_idx which can include higher
zones that kswapd tried to balance too, but didn't consider them in
pgdat_balanced().
Since kswapd now cannot create high-order pages itself, we need to
adjust how it determines the zones to be balanced. The key element here
is adding a "highorder" parameter to zone_balanced, which, when set to
false, makes it consider only order-0 watermark instead of the desired
higher order (this was done previously by kswapd_shrink_zone(), but not
elsewhere). This false is passed for example in pgdat_balanced().
Importantly, wakeup_kswapd() uses true to make sure kswapd and thus
kcompactd are woken up for a high-order allocation failure.
The last thing is to decide what to do with pageblock_skip bitmap
handling. Compaction maintains a pageblock_skip bitmap to record
pageblocks where isolation recently failed. This bitmap can be reset by
three ways:
1) direct compaction is restarting after going through the full deferred cycle
2) kswapd goes to sleep, and some other direct compaction has previously
finished scanning the whole zone and set zone->compact_blockskip_flush.
Note that a successful direct compaction clears this flag.
3) compaction was invoked manually via trigger in /proc
The case 2) is somewhat fuzzy to begin with, but after introducing
kcompactd we should update it. The check for direct compaction in 1),
and to set the flush flag in 2) use current_is_kswapd(), which doesn't
work for kcompactd. Thus, this patch adds bool direct_compaction to
compact_control to use in 2). For the case 1) we remove the check
completely - unlike the former kswapd compaction, kcompactd does use the
deferred compaction functionality, so flushing tied to restarting from
deferred compaction makes sense here.
Note that when kswapd goes to sleep, kcompactd is woken up, so it will
see the flushed pageblock_skip bits. This is different from when the
former kswapd compaction observed the bits and I believe it makes more
sense. Kcompactd can afford to be more thorough than a direct
compaction trying to limit allocation latency, or kswapd whose primary
goal is to reclaim.
For testing, I used stress-highalloc configured to do order-9
allocations with GFP_NOWAIT|__GFP_HIGH|__GFP_COMP, so they relied just
on kswapd/kcompactd reclaim/compaction (the interfering kernel builds in
phases 1 and 2 work as usual):
stress-highalloc
4.5-rc1+before 4.5-rc1+after
-nodirect -nodirect
Success 1 Min 1.00 ( 0.00%) 5.00 (-66.67%)
Success 1 Mean 1.40 ( 0.00%) 6.20 (-55.00%)
Success 1 Max 2.00 ( 0.00%) 7.00 (-16.67%)
Success 2 Min 1.00 ( 0.00%) 5.00 (-66.67%)
Success 2 Mean 1.80 ( 0.00%) 6.40 (-52.38%)
Success 2 Max 3.00 ( 0.00%) 7.00 (-16.67%)
Success 3 Min 34.00 ( 0.00%) 62.00 ( 1.59%)
Success 3 Mean 41.80 ( 0.00%) 63.80 ( 1.24%)
Success 3 Max 53.00 ( 0.00%) 65.00 ( 2.99%)
User 3166.67 3181.09
System 1153.37 1158.25
Elapsed 1768.53 1799.37
4.5-rc1+before 4.5-rc1+after
-nodirect -nodirect
Direct pages scanned 32938 32797
Kswapd pages scanned 2183166 2202613
Kswapd pages reclaimed 2152359 2143524
Direct pages reclaimed 32735 32545
Percentage direct scans 1% 1%
THP fault alloc 579 612
THP collapse alloc 304 316
THP splits 0 0
THP fault fallback 793 778
THP collapse fail 11 16
Compaction stalls 1013 1007
Compaction success 92 67
Compaction failures 920 939
Page migrate success 238457 721374
Page migrate failure 23021 23469
Compaction pages isolated 504695 1479924
Compaction migrate scanned 661390 8812554
Compaction free scanned 13476658 84327916
Compaction cost 262 838
After this patch we see improvements in allocation success rate
(especially for phase 3) along with increased compaction activity. The
compaction stalls (direct compaction) in the interfering kernel builds
(probably THP's) also decreased somewhat thanks to kcompactd activity,
yet THP alloc successes improved a bit.
Note that elapsed and user time isn't so useful for this benchmark,
because of the background interference being unpredictable. It's just
to quickly spot some major unexpected differences. System time is
somewhat more useful and that didn't increase.
Also (after adjusting mmtests' ftrace monitor):
Time kswapd awake 2547781 2269241
Time kcompactd awake 0 119253
Time direct compacting 939937 557649
Time kswapd compacting 0 0
Time kcompactd compacting 0 119099
The decrease of overal time spent compacting appears to not match the
increased compaction stats. I suspect the tasks get rescheduled and
since the ftrace monitor doesn't see that, the reported time is wall
time, not CPU time. But arguably direct compactors care about overall
latency anyway, whether busy compacting or waiting for CPU doesn't
matter. And that latency seems to almost halved.
It's also interesting how much time kswapd spent awake just going
through all the priorities and failing to even try compacting, over and
over.
We can also configure stress-highalloc to perform both direct
reclaim/compaction and wakeup kswapd/kcompactd, by using
GFP_KERNEL|__GFP_HIGH|__GFP_COMP:
stress-highalloc
4.5-rc1+before 4.5-rc1+after
-direct -direct
Success 1 Min 4.00 ( 0.00%) 9.00 (-50.00%)
Success 1 Mean 8.00 ( 0.00%) 10.00 (-19.05%)
Success 1 Max 12.00 ( 0.00%) 11.00 ( 15.38%)
Success 2 Min 4.00 ( 0.00%) 9.00 (-50.00%)
Success 2 Mean 8.20 ( 0.00%) 10.00 (-16.28%)
Success 2 Max 13.00 ( 0.00%) 11.00 ( 8.33%)
Success 3 Min 75.00 ( 0.00%) 74.00 ( 1.33%)
Success 3 Mean 75.60 ( 0.00%) 75.20 ( 0.53%)
Success 3 Max 77.00 ( 0.00%) 76.00 ( 0.00%)
User 3344.73 3246.04
System 1194.24 1172.29
Elapsed 1838.04 1836.76
4.5-rc1+before 4.5-rc1+after
-direct -direct
Direct pages scanned 125146 120966
Kswapd pages scanned 2119757 2135012
Kswapd pages reclaimed 2073183 2108388
Direct pages reclaimed 124909 120577
Percentage direct scans 5% 5%
THP fault alloc 599 652
THP collapse alloc 323 354
THP splits 0 0
THP fault fallback 806 793
THP collapse fail 17 16
Compaction stalls 2457 2025
Compaction success 906 518
Compaction failures 1551 1507
Page migrate success 2031423 2360608
Page migrate failure 32845 40852
Compaction pages isolated 4129761 4802025
Compaction migrate scanned 11996712 21750613
Compaction free scanned 214970969 344372001
Compaction cost 2271 2694
In this scenario, this patch doesn't change the overall success rate as
direct compaction already tries all it can. There's however significant
reduction in direct compaction stalls (that is, the number of
allocations that went into direct compaction). The number of successes
(i.e. direct compaction stalls that ended up with successful
allocation) is reduced by the same number. This means the offload to
kcompactd is working as expected, and direct compaction is reduced
either due to detecting contention, or compaction deferred by kcompactd.
In the previous version of this patchset there was some apparent
reduction of success rate, but the changes in this version (such as
using sync compaction only), new baseline kernel, and/or averaging
results from 5 executions (my bet), made this go away.
Ftrace-based stats seem to roughly agree:
Time kswapd awake 2532984 2326824
Time kcompactd awake 0 257916
Time direct compacting 864839 735130
Time kswapd compacting 0 0
Time kcompactd compacting 0 257585
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: David Rientjes <rientjes@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: accf62422b3a67fce8ce086aa81c8300ddbf42be
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Change-Id: I5cc784ff0fb1b28bdcfa8d4ef9bd33f585ee4662
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
We can reuse the nid we've determined instead of repeated pfn_to_nid()
usages. Also zone_to_nid() should be a bit cheaper in general than
pfn_to_nid().
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: David Rientjes <rientjes@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: e888ca3545dc6823603b976e40b62af2c68b6fcc
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Change-Id: I6bdb2530fd6306ceb49022ef9cdc82b5598ebe8c
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
Memory compaction can be currently performed in several contexts:
- kswapd balancing a zone after a high-order allocation failure
- direct compaction to satisfy a high-order allocation, including THP
page fault attemps
- khugepaged trying to collapse a hugepage
- manually from /proc
The purpose of compaction is two-fold. The obvious purpose is to
satisfy a (pending or future) high-order allocation, and is easy to
evaluate. The other purpose is to keep overal memory fragmentation low
and help the anti-fragmentation mechanism. The success wrt the latter
purpose is more
The current situation wrt the purposes has a few drawbacks:
- compaction is invoked only when a high-order page or hugepage is not
available (or manually). This might be too late for the purposes of
keeping memory fragmentation low.
- direct compaction increases latency of allocations. Again, it would
be better if compaction was performed asynchronously to keep
fragmentation low, before the allocation itself comes.
- (a special case of the previous) the cost of compaction during THP
page faults can easily offset the benefits of THP.
- kswapd compaction appears to be complex, fragile and not working in
some scenarios. It could also end up compacting for a high-order
allocation request when it should be reclaiming memory for a later
order-0 request.
To improve the situation, we should be able to benefit from an
equivalent of kswapd, but for compaction - i.e. a background thread
which responds to fragmentation and the need for high-order allocations
(including hugepages) somewhat proactively.
One possibility is to extend the responsibilities of kswapd, which could
however complicate its design too much. It should be better to let
kswapd handle reclaim, as order-0 allocations are often more critical
than high-order ones.
Another possibility is to extend khugepaged, but this kthread is a
single instance and tied to THP configs.
This patch goes with the option of a new set of per-node kthreads called
kcompactd, and lays the foundations, without introducing any new
tunables. The lifecycle mimics kswapd kthreads, including the memory
hotplug hooks.
For compaction, kcompactd uses the standard compaction_suitable() and
ompact_finished() criteria and the deferred compaction functionality.
Unlike direct compaction, it uses only sync compaction, as there's no
allocation latency to minimize.
This patch doesn't yet add a call to wakeup_kcompactd. The kswapd
compact/reclaim loop for high-order pages will be replaced by waking up
kcompactd in the next patch with the description of what's wrong with
the old approach.
Waking up of the kcompactd threads is also tied to kswapd activity and
follows these rules:
- we don't want to affect any fastpaths, so wake up kcompactd only from
the slowpath, as it's done for kswapd
- if kswapd is doing reclaim, it's more important than compaction, so
don't invoke kcompactd until kswapd goes to sleep
- the target order used for kswapd is passed to kcompactd
Future possible future uses for kcompactd include the ability to wake up
kcompactd on demand in special situations, such as when hugepages are
not available (currently not done due to __GFP_NO_KSWAPD) or when a
fragmentation event (i.e. __rmqueue_fallback()) occurs. It's also
possible to perform periodic compaction with kcompactd.
[arnd@arndb.de: fix build errors with kcompactd]
[paul.gortmaker@windriver.com: don't use modular references for non modular code]
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: David Rientjes <rientjes@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: 698b1b30642f1ff0ea10ef1de9745ab633031377
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Change-Id: I987ae548cba936987b8479dc02de67d0f88b9cb6
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
During work on kcompactd integration I have spotted a confusing check of
balance_classzone_idx, which I believe is bogus.
The balanced_classzone_idx is filled by balance_pgdat() as the highest
zone it attempted to balance. This was introduced by commit dc83edd941
("mm: kswapd: use the classzone idx that kswapd was using for
sleeping_prematurely()").
The intention is that (as expressed in today's function names), the
value used for kswapd_shrink_zone() calls in balance_pgdat() is the same
as for the decisions in kswapd_try_to_sleep().
An unwanted side-effect of that commit was breaking the checks in
kswapd() whether there was another kswapd_wakeup with a tighter (=lower)
classzone_idx. Commits 215ddd6664 ("mm: vmscan: only read
new_classzone_idx from pgdat when reclaiming successfully") and
d2ebd0f6b8 ("kswapd: avoid unnecessary rebalance after an unsuccessful
balancing") tried to fixed, but apparently introduced a bogus check that
this patch removes.
Consider zone indexes X < Y < Z, where:
- Z is the value used for the first kswapd wakeup.
- Y is returned as balanced_classzone_idx, which means zones with index higher
than Y (including Z) were found to be unreclaimable.
- X is the value used for the second kswapd wakeup
The new wakeup with value X means that kswapd is now supposed to balance
harder all zones with index <= X. But instead, due to Y < Z, it will go
sleep and won't read the new value X. This is subtly wrong.
The effect of this patch is that kswapd will react better in some
situations, where e.g. the first wakeup is for ZONE_DMA32, the second is
for ZONE_DMA, and due to unreclaimable ZONE_NORMAL. Before this patch,
kswapd would go sleep instead of reclaiming ZONE_DMA harder. I expect
these situations are very rare, and more value is in better
maintainability due to the removal of confusing and bogus check.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: David Rientjes <rientjes@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: 81c5857b279e6b18f6ff0d1975e80a07af542cd1
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Change-Id: If520144bb67b346a739166721137284112b9816a
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
During global reclaim, the nr_reclaimed passed to vmpressure includes the
pages reclaimed from slab. But the corresponding scanned slab pages is
not passed. There is an impact to the vmpressure values because of this.
While moving from kernel version 3.18 to 4.4, a difference is seen in the
vmpressure values for the same workload resulting in a different behaviour
of the vmpressure consumer. One such case is of a vmpressure based
lowmemorykiller. It is observed that the vmpressure events are received
late and less in number resulting in tasks not being killed at the right
time. The following numbers show the impact on reclaim activity due to
the change in behaviour of lowmemorykiller on a 4GB device. The test
launches a number of apps in sequence and repeats it multiple times.
v4.4 v3.18
pgpgin 163016456 145617236
pgpgout 4366220 4188004
workingset_refault 29857868 26781854
workingset_activate 6293946 5634625
pswpin 1327601 1133912
pswpout 3593842 3229602
pgalloc_dma 99520618 94402970
pgalloc_normal 104046854 98124798
pgfree 203772640 192600737
pgmajfault 2126962 1851836
pgsteal_kswapd_dma 19732899 18039462
pgsteal_kswapd_normal 19945336 17977706
pgsteal_direct_dma 206757 131376
pgsteal_direct_normal 236783 138247
pageoutrun 116622 108370
allocstall 7220 4684
compact_stall 931 856
This is a regression introduced by commit 6b4f7799c6 ("mm: vmscan:
invoke slab shrinkers from shrink_zone()").
So do not consider reclaimed slab pages for vmpressure calculation. The
reclaimed pages from slab can be excluded because the freeing of a page by
slab shrinking depends on each slab's object population, making the cost
model (i.e. scan:free) different from that of LRU. Also, not every
shrinker accounts the pages it reclaims. But ideally the pages reclaimed
from slab should be passed to vmpressure, otherwise higher vmpressure
levels can be triggered even when there is a reclaim progress. But
accounting only the reclaimed slab pages without the scanned, and adding
something which does not fit into the cost model just adds noise to the
vmpressure values.
Fixes: 6b4f7799c6 ("mm: vmscan: invoke slab shrinkers from shrink_zone()")
Link: http://lkml.kernel.org/r/1486641577-11685-2-git-send-email-vinmenon@codeaurora.org
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Anton Vorontsov <anton.vorontsov@linaro.org>
Cc: Shiraz Hashim <shashim@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Git-commit: 97a9668a428e9651a4aa3ff5d4e7e60024be2d87
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
Change-Id: If46b1cee6fd9723bebd87d76e0bb8451de05a9c1
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
At the end of a window period, if the reclaimed pages is greater than
scanned, an unsigned underflow can result in a huge pressure value and
thus a critical event. Reclaimed pages is found to go higher than scanned
because of the addition of reclaimed slab pages to reclaimed in
shrink_node without a corresponding increment to scanned pages. Minchan
Kim mentioned that this can also happen in the case of a THP page where
the scanned is 1 and reclaimed could be 512.
Link: http://lkml.kernel.org/r/1486641577-11685-1-git-send-email-vinmenon@codeaurora.org
Acked-by: Minchan Kim <minchan@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Rik van Riel <riel@redhat.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Anton Vorontsov <anton.vorontsov@linaro.org>
Cc: Shiraz Hashim <shashim@codeaurora.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Change-Id: Ic1221fa129c9b3512127537d62df7bd4a7606d24
Git-commit: 746d8d8f3ebb49a62ffcffb4b1f41cc27d020a2e
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
There is race between page freeing and unreserved highatomic.
CPU 0 CPU 1
free_hot_cold_page
mt = get_pfnblock_migratetype
set_pcppage_migratetype(page, mt)
unreserve_highatomic_pageblock
spin_lock_irqsave(&zone->lock)
move_freepages_block
set_pageblock_migratetype(page)
spin_unlock_irqrestore(&zone->lock)
free_pcppages_bulk
__free_one_page(mt) <- mt is stale
By above race, a page on CPU 0 could go non-highorderatomic free list
since the pageblock's type is changed. By that, unreserve logic of
highorderatomic can decrease reserved count on a same pageblock severak
times and then it will make mismatch between nr_reserved_highatomic and
the number of reserved pageblock.
So, this patch verifies whether the pageblock is highatomic or not and
decrease the count only if the pageblock is highatomic.
Change-Id: Ieb4b6c0c98d1797339a94dd4b8033048552c9aad
Link: http://lkml.kernel.org/r/1476259429-18279-3-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Sangseok Lee <sangseok.lee@lge.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: 4855e4a7f29d6d10b0b9c84e189c770c9a94e91e
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Liam Mark <lmark@codeaurora.org>
Patch series "use up highorder free pages before OOM", v3.
I got OOM report from production team with v4.4 kernel. It had enough
free memory but failed to allocate GFP_KERNEL order-0 page and finally
encountered OOM kill. It occured during QA process which launches
several apps, switching and so on. It happned rarely. IOW, In normal
situation, it was not a problem but if we are unluck so that several
apps uses peak memory at the same time, it can happen. If we manage to
pass the phase, the system can go working well.
I could reproduce it with my test(memory spike easily. Look at below.
The reason is free pages(19M) of DMA32 zone are reserved for
HIGHORDERATOMIC and doesn't unreserved before the OOM.
balloon invoked oom-killer: gfp_mask=0x24280ca(GFP_HIGHUSER_MOVABLE|__GFP_ZERO), order=0, oom_score_adj=0
balloon cpuset=/ mems_allowed=0
CPU: 1 PID: 8473 Comm: balloon Tainted: G W OE 4.8.0-rc7-00219-g3f74c9559583-dirty #3161
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
Call Trace:
dump_stack+0x63/0x90
dump_header+0x5c/0x1ce
oom_kill_process+0x22e/0x400
out_of_memory+0x1ac/0x210
__alloc_pages_nodemask+0x101e/0x1040
handle_mm_fault+0xa0a/0xbf0
__do_page_fault+0x1dd/0x4d0
trace_do_page_fault+0x43/0x130
do_async_page_fault+0x1a/0xa0
async_page_fault+0x28/0x30
Mem-Info:
active_anon:383949 inactive_anon:106724 isolated_anon:0
active_file:15 inactive_file:44 isolated_file:0
unevictable:0 dirty:0 writeback:24 unstable:0
slab_reclaimable:2483 slab_unreclaimable:3326
mapped:0 shmem:0 pagetables:1906 bounce:0
free:6898 free_pcp:291 free_cma:0
Node 0 active_anon:1535796kB inactive_anon:426896kB active_file:60kB inactive_file:176kB unevictable:0kB isolated(anon):0kB isolated(file):0kB mapped:0kB dirty:0kB writeback:96kB shmem:0kB writeback_tmp:0kB unstable:0kB pages_scanned:1418 all_unreclaimable? no
DMA free:8188kB min:44kB low:56kB high:68kB active_anon:7648kB inactive_anon:0kB active_file:0kB inactive_file:4kB unevictable:0kB writepending:0kB present:15992kB managed:15908kB mlocked:0kB slab_reclaimable:0kB slab_unreclaimable:20kB kernel_stack:0kB pagetables:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB
lowmem_reserve[]: 0 1952 1952 1952
DMA32 free:19404kB min:5628kB low:7624kB high:9620kB active_anon:1528148kB inactive_anon:426896kB active_file:60kB inactive_file:420kB unevictable:0kB writepending:96kB present:2080640kB managed:2030092kB mlocked:0kB slab_reclaimable:9932kB slab_unreclaimable:13284kB kernel_stack:2496kB pagetables:7624kB bounce:0kB free_pcp:900kB local_pcp:112kB free_cma:0kB
lowmem_reserve[]: 0 0 0 0
DMA: 0*4kB 0*8kB 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 2*4096kB (H) = 8192kB
DMA32: 7*4kB (H) 8*8kB (H) 30*16kB (H) 31*32kB (H) 14*64kB (H) 9*128kB (H) 2*256kB (H) 2*512kB (H) 4*1024kB (H) 5*2048kB (H) 0*4096kB = 19484kB
51131 total pagecache pages
50795 pages in swap cache
Swap cache stats: add 3532405601, delete 3532354806, find 124289150/1822712228
Free swap = 8kB
Total swap = 255996kB
524158 pages RAM
0 pages HighMem/MovableOnly
12658 pages reserved
0 pages cma reserved
0 pages hwpoisoned
Another example exceeded the limit by the race is
in:imklog: page allocation failure: order:0, mode:0x2280020(GFP_ATOMIC|__GFP_NOTRACK)
CPU: 0 PID: 476 Comm: in:imklog Tainted: G E 4.8.0-rc7-00217-g266ef83c51e5-dirty #3135
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
Call Trace:
dump_stack+0x63/0x90
warn_alloc_failed+0xdb/0x130
__alloc_pages_nodemask+0x4d6/0xdb0
new_slab+0x339/0x490
___slab_alloc.constprop.74+0x367/0x480
__slab_alloc.constprop.73+0x20/0x40
__kmalloc+0x1a4/0x1e0
alloc_indirect.isra.14+0x1d/0x50
virtqueue_add_sgs+0x1c4/0x470
__virtblk_add_req+0xae/0x1f0
virtio_queue_rq+0x12d/0x290
__blk_mq_run_hw_queue+0x239/0x370
blk_mq_run_hw_queue+0x8f/0xb0
blk_mq_insert_requests+0x18c/0x1a0
blk_mq_flush_plug_list+0x125/0x140
blk_flush_plug_list+0xc7/0x220
blk_finish_plug+0x2c/0x40
__do_page_cache_readahead+0x196/0x230
filemap_fault+0x448/0x4f0
ext4_filemap_fault+0x36/0x50
__do_fault+0x75/0x140
handle_mm_fault+0x84d/0xbe0
__do_page_fault+0x1dd/0x4d0
trace_do_page_fault+0x43/0x130
do_async_page_fault+0x1a/0xa0
async_page_fault+0x28/0x30
Mem-Info:
active_anon:363826 inactive_anon:121283 isolated_anon:32
active_file:65 inactive_file:152 isolated_file:0
unevictable:0 dirty:0 writeback:46 unstable:0
slab_reclaimable:2778 slab_unreclaimable:3070
mapped:112 shmem:0 pagetables:1822 bounce:0
free:9469 free_pcp:231 free_cma:0
Node 0 active_anon:1455304kB inactive_anon:485132kB active_file:260kB inactive_file:608kB unevictable:0kB isolated(anon):128kB isolated(file):0kB mapped:448kB dirty:0kB writeback:184kB shmem:0kB writeback_tmp:0kB unstable:0kB pages_scanned:13641 all_unreclaimable? no
DMA free:7748kB min:44kB low:56kB high:68kB active_anon:7944kB inactive_anon:104kB active_file:0kB inactive_file:0kB unevictable:0kB writepending:0kB present:15992kB managed:15908kB mlocked:0kB slab_reclaimable:0kB slab_unreclaimable:108kB kernel_stack:0kB pagetables:4kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB
lowmem_reserve[]: 0 1952 1952 1952
DMA32 free:30128kB min:5628kB low:7624kB high:9620kB active_anon:1447360kB inactive_anon:485028kB active_file:260kB inactive_file:608kB unevictable:0kB writepending:184kB present:2080640kB managed:2030132kB mlocked:0kB slab_reclaimable:11112kB slab_unreclaimable:12172kB kernel_stack:2400kB pagetables:7284kB bounce:0kB free_pcp:924kB local_pcp:72kB free_cma:0kB
lowmem_reserve[]: 0 0 0 0
DMA: 7*4kB (UE) 3*8kB (UH) 1*16kB (M) 0*32kB 2*64kB (U) 1*128kB (M) 1*256kB (U) 0*512kB 1*1024kB (U) 1*2048kB (U) 1*4096kB (H) = 7748kB
DMA32: 10*4kB (H) 3*8kB (H) 47*16kB (H) 38*32kB (H) 5*64kB (H) 1*128kB (H) 2*256kB (H) 3*512kB (H) 3*1024kB (H) 3*2048kB (H) 4*4096kB (H) = 30128kB
2775 total pagecache pages
2536 pages in swap cache
Swap cache stats: add 206786828, delete 206784292, find 7323106/106686077
Free swap = 108744kB
Total swap = 255996kB
524158 pages RAM
0 pages HighMem/MovableOnly
12648 pages reserved
0 pages cma reserved
0 pages hwpoisoned
During the investigation, I found some problems with highatomic so this
patch aims to solve the problems and the final goal is to unreserve
every highatomic free pages before the OOM kill.
This patch (of 4):
In page freeing path, migratetype is racy so that a highorderatomic page
could free into non-highorderatomic free list. If that page is
allocated, VM can change the pageblock from higorderatomic to something.
In that case, highatomic pageblock accounting is broken so it doesn't
work(e.g., VM cannot reserve highorderatomic pageblocks any more
although it doesn't reach 1% limit).
So, this patch prohibits the changing from highatomic to other type.
It's no problem because MIGRATE_HIGHATOMIC is not listed in fallback
array so stealing will only happen due to unexpected races which is
really rare. Also, such prohibiting keeps highatomic pageblock more
longer so it would be better for highorderatomic page allocation.
Change-Id: I15c2f91965eb4c35a2a53dc43f9acb8945922198
Link: http://lkml.kernel.org/r/1476259429-18279-2-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Sangseok Lee <sangseok.lee@lge.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: 88ed365ea227aa28841a8d6e196c9a261c76fffd
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Liam Mark <lmark@codeaurora.org>
Fix a compile time error introduced by
'commit 334ca3ed18 ("Merge branch 'linux-linaro-lsk-v4.4'
into linux-linaro-lsk-v4.4-android")'
Change-Id: I1af8d539a1ce07e16f6c46f855c65cc4985de737
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
The grouping of tasks based on oom_score_adj values change from
one framework to another. This requires corresponding changes in
the threshold values set for almk and per process reclaim.
Introduce sysfs nodes to set threshold adj for process reclaim
and adaptive LMK dynamically.
Change-Id: Ib7565bfd5d2e93aa4ff8fdd20414cac0a0f38bf7
Signed-off-by: Suyog Sarda <ssarda@codeaurora.org>
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
* v4.4-16.09-android-tmp:
unsafe_[get|put]_user: change interface to use a error target label
usercopy: remove page-spanning test for now
usercopy: fix overlap check for kernel text
mm/slub: support left redzone
Linux 4.4.21
lib/mpi: mpi_write_sgl(): fix skipping of leading zero limbs
regulator: anatop: allow regulator to be in bypass mode
hwrng: exynos - Disable runtime PM on probe failure
cpufreq: Fix GOV_LIMITS handling for the userspace governor
metag: Fix atomic_*_return inline asm constraints
scsi: fix upper bounds check of sense key in scsi_sense_key_string()
ALSA: timer: fix NULL pointer dereference on memory allocation failure
ALSA: timer: fix division by zero after SNDRV_TIMER_IOCTL_CONTINUE
ALSA: timer: fix NULL pointer dereference in read()/ioctl() race
ALSA: hda - Enable subwoofer on Dell Inspiron 7559
ALSA: hda - Add headset mic quirk for Dell Inspiron 5468
ALSA: rawmidi: Fix possible deadlock with virmidi registration
ALSA: fireworks: accessing to user space outside spinlock
ALSA: firewire-tascam: accessing to user space outside spinlock
ALSA: usb-audio: Add sample rate inquiry quirk for B850V3 CP2114
crypto: caam - fix IV loading for authenc (giv)decryption
uprobes: Fix the memcg accounting
x86/apic: Do not init irq remapping if ioapic is disabled
vhost/scsi: fix reuse of &vq->iov[out] in response
bcache: RESERVE_PRIO is too small by one when prio_buckets() is a power of two.
ubifs: Fix assertion in layout_in_gaps()
ovl: fix workdir creation
ovl: listxattr: use strnlen()
ovl: remove posix_acl_default from workdir
ovl: don't copy up opaqueness
wrappers for ->i_mutex access
lustre: remove unused declaration
timekeeping: Avoid taking lock in NMI path with CONFIG_DEBUG_TIMEKEEPING
timekeeping: Cap array access in timekeeping_debug
xfs: fix superblock inprogress check
ASoC: atmel_ssc_dai: Don't unconditionally reset SSC on stream startup
drm/msm: fix use of copy_from_user() while holding spinlock
drm: Reject page_flip for !DRIVER_MODESET
drm/radeon: fix radeon_move_blit on 32bit systems
s390/sclp_ctl: fix potential information leak with /dev/sclp
rds: fix an infoleak in rds_inc_info_copy
powerpc/tm: Avoid SLB faults in treclaim/trecheckpoint when RI=0
nvme: Call pci_disable_device on the error path.
cgroup: reduce read locked section of cgroup_threadgroup_rwsem during fork
block: make sure a big bio is split into at most 256 bvecs
block: Fix race triggered by blk_set_queue_dying()
ext4: avoid modifying checksum fields directly during checksum verification
ext4: avoid deadlock when expanding inode size
ext4: properly align shifted xattrs when expanding inodes
ext4: fix xattr shifting when expanding inodes part 2
ext4: fix xattr shifting when expanding inodes
ext4: validate that metadata blocks do not overlap superblock
net: Use ns_capable_noaudit() when determining net sysctl permissions
kernel: Add noaudit variant of ns_capable()
KEYS: Fix ASN.1 indefinite length object parsing
drivers:hv: Lock access to hyperv_mmio resource tree
cxlflash: Move to exponential back-off when cmd_room is not available
netfilter: x_tables: check for size overflow
drm/amdgpu/cz: enable/disable vce dpm even if vce pg is disabled
cred: Reject inodes with invalid ids in set_create_file_as()
fs: Check for invalid i_uid in may_follow_link()
IB/IPoIB: Do not set skb truesize since using one linearskb
udp: properly support MSG_PEEK with truncated buffers
crypto: nx-842 - Mask XERS0 bit in return value
cxlflash: Fix to avoid virtual LUN failover failure
cxlflash: Fix to escalate LINK_RESET also on port 1
tipc: fix nl compat regression for link statistics
tipc: fix an infoleak in tipc_nl_compat_link_dump
netfilter: x_tables: check for size overflow
Bluetooth: Add support for Intel Bluetooth device 8265 [8087:0a2b]
drm/i915: Check VBT for port presence in addition to the strap on VLV/CHV
drm/i915: Only ignore eDP ports that are connected
Input: xpad - move pending clear to the correct location
net: thunderx: Fix link status reporting
x86/hyperv: Avoid reporting bogus NMI status for Gen2 instances
crypto: vmx - IV size failing on skcipher API
tda10071: Fix dependency to REGMAP_I2C
crypto: vmx - Fix ABI detection
crypto: vmx - comply with ABIs that specify vrsave as reserved.
HID: core: prevent out-of-bound readings
lpfc: Fix DMA faults observed upon plugging loopback connector
block: fix blk_rq_get_max_sectors for driver private requests
irqchip/gicv3-its: numa: Enable workaround for Cavium thunderx erratum 23144
clocksource: Allow unregistering the watchdog
btrfs: Continue write in case of can_not_nocow
blk-mq: End unstarted requests on dying queue
cxlflash: Fix to resolve dead-lock during EEH recovery
drm/radeon/mst: fix regression in lane/link handling.
ecryptfs: fix handling of directory opening
ALSA: hda: add AMD Polaris-10/11 AZ PCI IDs with proper driver caps
drm: Balance error path for GEM handle allocation
ntp: Fix ADJ_SETOFFSET being used w/ ADJ_NANO
time: Verify time values in adjtimex ADJ_SETOFFSET to avoid overflow
Input: xpad - correctly handle concurrent LED and FF requests
net: thunderx: Fix receive packet stats
net: thunderx: Fix for multiqset not configured upon interface toggle
perf/x86/cqm: Fix CQM memory leak and notifier leak
perf/x86/cqm: Fix CQM handling of grouping events into a cache_group
s390/crypto: provide correct file mode at device register.
proc: revert /proc/<pid>/maps [stack:TID] annotation
intel_idle: Support for Intel Xeon Phi Processor x200 Product Family
cxlflash: Fix to avoid unnecessary scan with internal LUNs
Drivers: hv: vmbus: don't manipulate with clocksources on crash
Drivers: hv: vmbus: avoid scheduling in interrupt context in vmbus_initiate_unload()
Drivers: hv: vmbus: avoid infinite loop in init_vp_index()
arcmsr: fixes not release allocated resource
arcmsr: fixed getting wrong configuration data
s390/pci_dma: fix DMA table corruption with > 4 TB main memory
net/mlx5e: Don't modify CQ before it was created
net/mlx5e: Don't try to modify CQ moderation if it is not supported
mmc: sdhci: Do not BUG on invalid vdd
UVC: Add support for R200 depth camera
sched/numa: Fix use-after-free bug in the task_numa_compare
ALSA: hda - add codec support for Kabylake display audio codec
drm/i915: Fix hpd live status bits for g4x
tipc: fix nullptr crash during subscription cancel
arm64: Add workaround for Cavium erratum 27456
net: thunderx: Fix for Qset error due to CQ full
drm/radeon: fix dp link rate selection (v2)
drm/amdgpu: fix dp link rate selection (v2)
qla2xxx: Use ATIO type to send correct tmr response
mmc: sdhci: 64-bit DMA actually has 4-byte alignment
drm/atomic: Do not unset crtc when an encoder is stolen
drm/i915/skl: Add missing SKL ids
drm/i915/bxt: update list of PCIIDs
hrtimer: Catch illegal clockids
i40e/i40evf: Fix RSS rx-flow-hash configuration through ethtool
mpt3sas: Fix for Asynchronous completion of timedout IO and task abort of timedout IO.
mpt3sas: A correction in unmap_resources
net: cavium: liquidio: fix check for in progress flag
arm64: KVM: Configure TCR_EL2.PS at runtime
irqchip/gic-v3: Make sure read from ICC_IAR1_EL1 is visible on redestributor
pwm: lpc32xx: fix and simplify duty cycle and period calculations
pwm: lpc32xx: correct number of PWM channels from 2 to 1
pwm: fsl-ftm: Fix clock enable/disable when using PM
megaraid_sas: Add an i/o barrier
megaraid_sas: Fix SMAP issue
megaraid_sas: Do not allow PCI access during OCR
s390/cio: update measurement characteristics
s390/cio: ensure consistent measurement state
s390/cio: fix measurement characteristics memleak
qeth: initialize net_device with carrier off
lpfc: Fix external loopback failure.
lpfc: Fix mbox reuse in PLOGI completion
lpfc: Fix RDP Speed reporting.
lpfc: Fix crash in fcp command completion path.
lpfc: Fix driver crash when module parameter lpfc_fcp_io_channel set to 16
lpfc: Fix RegLogin failed error seen on Lancer FC during port bounce
lpfc: Fix the FLOGI discovery logic to comply with T11 standards
lpfc: Fix FCF Infinite loop in lpfc_sli4_fcf_rr_next_index_get.
cxl: Enable PCI device ID for future IBM CXL adapter
cxl: fix build for GCC 4.6.x
cxlflash: Enable device id for future IBM CXL adapter
cxlflash: Resolve oops in wait_port_offline
cxlflash: Fix to resolve cmd leak after host reset
cxl: Fix DSI misses when the context owning task exits
cxl: Fix possible idr warning when contexts are released
Drivers: hv: vmbus: fix rescind-offer handling for device without a driver
Drivers: hv: vmbus: serialize process_chn_event() and vmbus_close_internal()
Drivers: hv: vss: run only on supported host versions
drivers/hv: cleanup synic msrs if vmbus connect failed
Drivers: hv: util: catch allocation errors
tools: hv: report ENOSPC errors in hv_fcopy_daemon
Drivers: hv: utils: run polling callback always in interrupt context
Drivers: hv: util: Increase the timeout for util services
lightnvm: fix missing grown bad block type
lightnvm: fix locking and mempool in rrpc_lun_gc
lightnvm: unlock rq and free ppa_list on submission fail
lightnvm: add check after mempool allocation
lightnvm: fix incorrect nr_free_blocks stat
lightnvm: fix bio submission issue
cxlflash: a couple off by one bugs
fm10k: Cleanup exception handling for mailbox interrupt
fm10k: Cleanup MSI-X interrupts in case of failure
fm10k: reinitialize queuing scheme after calling init_hw
fm10k: always check init_hw for errors
fm10k: reset max_queues on init_hw_vf failure
fm10k: Fix handling of NAPI budget when multiple queues are enabled per vector
fm10k: Correct MTU for jumbo frames
fm10k: do not assume VF always has 1 queue
clk: xgene: Fix divider with non-zero shift value
e1000e: fix division by zero on jumbo MTUs
e1000: fix data race between tx_ring->next_to_clean
ixgbe: Fix handling of NAPI budget when multiple queues are enabled per vector
igb: fix NULL derefs due to skipped SR-IOV enabling
igb: use the correct i210 register for EEMNGCTL
igb: don't unmap NULL hw_addr
i40e: Fix Rx hash reported to the stack by our driver
i40e: clean whole mac filter list
i40evf: check rings before freeing resources
i40e: don't add zero MAC filter
i40e: properly delete VF MAC filters
i40e: Fix memory leaks, sideband filter programming
i40e: fix: do not sleep in netdev_ops
i40e/i40evf: Fix RS bit update in Tx path and disable force WB workaround
i40evf: handle many MAC filters correctly
i40e: Workaround fix for mss < 256 issue
UPSTREAM: audit: fix a double fetch in audit_log_single_execve_arg()
UPSTREAM: ARM: 8494/1: mm: Enable PXN when running non-LPAE kernel on LPAE processor
FIXUP: sched/tune: update accouting before CPU capacity
FIXUP: sched/tune: add fixes missing from a previous patch
arm: Fix #if/#ifdef typo in topology.c
arm: Fix build error "conflicting types for 'scale_cpu_capacity'"
sched/walt: use do_div instead of division operator
DEBUG: cpufreq: fix cpu_capacity tracing build for non-smp systems
sched/walt: include missing header for arm_timer_read_counter()
cpufreq: Kconfig: Fixup incorrect selection by CPU_FREQ_DEFAULT_GOV_SCHED
sched/fair: Avoid redundant idle_cpu() call in update_sg_lb_stats()
FIXUP: sched: scheduler-driven cpu frequency selection
sched/rt: Add Kconfig option to enable panicking for RT throttling
sched/rt: print RT tasks when RT throttling is activated
UPSTREAM: sched: Fix a race between __kthread_bind() and sched_setaffinity()
sched/fair: Favor higher cpus only for boosted tasks
vmstat: make vmstat_updater deferrable again and shut down on idle
sched/fair: call OPP update when going idle after migration
sched/cpufreq_sched: fix thermal capping events
sched/fair: Picking cpus with low OPPs for tasks that prefer idle CPUs
FIXUP: sched/tune: do initialization as a postcore_initicall
DEBUG: sched: add tracepoint for RD overutilized
sched/tune: Introducing a new schedtune attribute prefer_idle
sched: use util instead of capacity to select busy cpu
arch_timer: add error handling when the MPM global timer is cleared
FIXUP: sched: Fix double-release of spinlock in move_queued_task
FIXUP: sched/fair: Fix hang during suspend in sched_group_energy
FIXUP: sched: fix SchedFreq integration for both PELT and WALT
sched: EAS: Avoid causing spikes to max-freq unnecessarily
FIXUP: sched: fix set_cfs_cpu_capacity when WALT is in use
sched/walt: Accounting for number of irqs pending on each core
sched: Introduce Window Assisted Load Tracking (WALT)
sched/tune: fix PB and PC cuts indexes definition
sched/fair: optimize idle cpu selection for boosted tasks
FIXUP: sched/tune: fix accounting for runnable tasks
sched/tune: use a single initialisation function
sched/{fair,tune}: simplify fair.c code
FIXUP: sched/tune: fix payoff calculation for boost region
sched/tune: Add support for negative boost values
FIX: sched/tune: move schedtune_nornalize_energy into fair.c
FIX: sched/tune: update usage of boosted task utilisation on CPU selection
sched/fair: add tunable to set initial task load
sched/fair: add tunable to force selection at cpu granularity
sched: EAS: take cstate into account when selecting idle core
sched/cpufreq_sched: Consolidated update
FIXUP: sched: fix build for non-SMP target
DEBUG: sched/tune: add tracepoint on P-E space filtering
DEBUG: sched/tune: add tracepoint for energy_diff() values
DEBUG: sched/tune: add tracepoint for task boost signal
arm: topology: Define TC2 energy and provide it to the scheduler
CHROMIUM: sched: update the average of nr_running
DEBUG: schedtune: add tracepoint for schedtune_tasks_update() values
DEBUG: schedtune: add tracepoint for CPU boost signal
DEBUG: schedtune: add tracepoint for SchedTune configuration update
DEBUG: sched: add energy procfs interface
DEBUG: sched,cpufreq: add cpu_capacity change tracepoint
DEBUG: sched: add tracepoint for CPU load/util signals
DEBUG: sched: add tracepoint for task load/util signals
DEBUG: sched: add tracepoint for cpu/freq scale invariance
sched/fair: filter energy_diff() based on energy_payoff value
sched/tune: add support to compute normalized energy
sched/fair: keep track of energy/capacity variations
sched/fair: add boosted task utilization
sched/{fair,tune}: track RUNNABLE tasks impact on per CPU boost value
sched/tune: compute and keep track of per CPU boost value
sched/tune: add initial support for CGroups based boosting
sched/fair: add boosted CPU usage
sched/fair: add function to convert boost value into "margin"
sched/tune: add sysctl interface to define a boost value
sched/tune: add detailed documentation
fixup! sched/fair: jump to max OPP when crossing UP threshold
fixup! sched: scheduler-driven cpu frequency selection
sched: rt scheduler sets capacity requirement
sched: deadline: use deadline bandwidth in scale_rt_capacity
sched: remove call of sched_avg_update from sched_rt_avg_update
sched/cpufreq_sched: add trace events
sched/fair: jump to max OPP when crossing UP threshold
sched/fair: cpufreq_sched triggers for load balancing
sched/{core,fair}: trigger OPP change request on fork()
sched/fair: add triggers for OPP change requests
sched: scheduler-driven cpu frequency selection
cpufreq: introduce cpufreq_driver_is_slow
sched: Consider misfit tasks when load-balancing
sched: Add group_misfit_task load-balance type
sched: Add per-cpu max capacity to sched_group_capacity
sched: Do eas idle balance regardless of the rq avg idle value
arm64: Enable max freq invariant scheduler load-tracking and capacity support
arm: Enable max freq invariant scheduler load-tracking and capacity support
sched: Update max cpu capacity in case of max frequency constraints
cpufreq: Max freq invariant scheduler load-tracking and cpu capacity support
arm64, topology: Updates to use DT bindings for EAS costing data
sched: Support for extracting EAS energy costs from DT
Documentation: DT bindings for energy model cost data required by EAS
sched: Disable energy-unfriendly nohz kicks
sched: Consider a not over-utilized energy-aware system as balanced
sched: Energy-aware wake-up task placement
sched: Determine the current sched_group idle-state
sched, cpuidle: Track cpuidle state index in the scheduler
sched: Add over-utilization/tipping point indicator
sched: Estimate energy impact of scheduling decisions
sched: Extend sched_group_energy to test load-balancing decisions
sched: Calculate energy consumption of sched_group
sched: Highest energy aware balancing sched_domain level pointer
sched: Relocated cpu_util() and change return type
sched: Compute cpu capacity available at current frequency
arm64: Cpu invariant scheduler load-tracking and capacity support
arm: Cpu invariant scheduler load-tracking and capacity support
sched: Introduce SD_SHARE_CAP_STATES sched_domain flag
sched: Initialize energy data structures
sched: Introduce energy data structures
sched: Make energy awareness a sched feature
sched: Documentation for scheduler energy cost model
sched: Prevent unnecessary active balance of single task in sched group
sched: Enable idle balance to pull single task towards cpu with higher capacity
sched: Consider spare cpu capacity at task wake-up
sched: Add cpu capacity awareness to wakeup balancing
sched: Store system-wide maximum cpu capacity in root domain
arm: Update arch_scale_cpu_capacity() to reflect change to define
arm64: Enable frequency invariant scheduler load-tracking support
arm: Enable frequency invariant scheduler load-tracking support
cpufreq: Frequency invariant scheduler load-tracking support
sched/fair: Fix new task's load avg removed from source CPU in wake_up_new_task()
FROMLIST: pstore: drop pmsg bounce buffer
UPSTREAM: usercopy: remove page-spanning test for now
UPSTREAM: usercopy: force check_object_size() inline
BACKPORT: usercopy: fold builtin_const check into inline function
UPSTREAM: x86/uaccess: force copy_*_user() to be inlined
UPSTREAM: HID: core: prevent out-of-bound readings
Android: Fix build breakages.
UPSTREAM: tty: Prevent ldisc drivers from re-using stale tty fields
UPSTREAM: netfilter: nfnetlink: correctly validate length of batch messages
cpuset: Make cpusets restore on hotplug
UPSTREAM: mm/slub: support left redzone
UPSTREAM: Make the hardened user-copy code depend on having a hardened allocator
Android: MMC/UFS IO Latency Histograms.
UPSTREAM: usercopy: fix overlap check for kernel text
UPSTREAM: usercopy: avoid potentially undefined behavior in pointer math
UPSTREAM: unsafe_[get|put]_user: change interface to use a error target label
BACKPORT: arm64: mm: fix location of _etext
BACKPORT: ARM: 8583/1: mm: fix location of _etext
BACKPORT: Don't show empty tag stats for unprivileged uids
UPSTREAM: tcp: fix use after free in tcp_xmit_retransmit_queue()
ANDROID: base-cfg: drop SECCOMP_FILTER config
UPSTREAM: [media] xc2028: unlock on error in xc2028_set_config()
UPSTREAM: [media] xc2028: avoid use after free
ANDROID: base-cfg: enable SECCOMP config
ANDROID: rcu_sync: Export rcu_sync_lockdep_assert
RFC: FROMLIST: cgroup: reduce read locked section of cgroup_threadgroup_rwsem during fork
RFC: FROMLIST: cgroup: avoid synchronize_sched() in __cgroup_procs_write()
RFC: FROMLIST: locking/percpu-rwsem: Optimize readers and reduce global impact
net: ipv6: Fix ping to link-local addresses.
ipv6: fix endianness error in icmpv6_err
ANDROID: dm: android-verity: Allow android-verity to be compiled as an independent module
backporting: a brief introduce of backported feautures on 4.4
Linux 4.4.20
sysfs: correctly handle read offset on PREALLOC attrs
hwmon: (iio_hwmon) fix memory leak in name attribute
ALSA: line6: Fix POD sysfs attributes segfault
ALSA: line6: Give up on the lock while URBs are released.
ALSA: line6: Remove double line6_pcm_release() after failed acquire.
ACPI / SRAT: fix SRAT parsing order with both LAPIC and X2APIC present
ACPI / sysfs: fix error code in get_status()
ACPI / drivers: replace acpi_probe_lock spinlock with mutex
ACPI / drivers: fix typo in ACPI_DECLARE_PROBE_ENTRY macro
staging: comedi: ni_mio_common: fix wrong insn_write handler
staging: comedi: ni_mio_common: fix AO inttrig backwards compatibility
staging: comedi: comedi_test: fix timer race conditions
staging: comedi: daqboard2000: bug fix board type matching code
USB: serial: option: add WeTelecom 0x6802 and 0x6803 products
USB: serial: option: add WeTelecom WM-D200
USB: serial: mos7840: fix non-atomic allocation in write path
USB: serial: mos7720: fix non-atomic allocation in write path
USB: fix typo in wMaxPacketSize validation
usb: chipidea: udc: don't touch DP when controller is in host mode
USB: avoid left shift by -1
dmaengine: usb-dmac: check CHCR.DE bit in usb_dmac_isr_channel()
crypto: qat - fix aes-xts key sizes
crypto: nx - off by one bug in nx_of_update_msc()
Input: i8042 - set up shared ps2_cmd_mutex for AUX ports
Input: i8042 - break load dependency between atkbd/psmouse and i8042
Input: tegra-kbc - fix inverted reset logic
btrfs: properly track when rescan worker is running
btrfs: waiting on qgroup rescan should not always be interruptible
fs/seq_file: fix out-of-bounds read
gpio: Fix OF build problem on UM
usb: renesas_usbhs: gadget: fix return value check in usbhs_mod_gadget_probe()
megaraid_sas: Fix probing cards without io port
mpt3sas: Fix resume on WarpDrive flash cards
cdc-acm: fix wrong pipe type on rx interrupt xfers
i2c: cros-ec-tunnel: Fix usage of cros_ec_cmd_xfer()
mfd: cros_ec: Add cros_ec_cmd_xfer_status() helper
aacraid: Check size values after double-fetch from user
ARC: Elide redundant setup of DMA callbacks
ARC: Call trace_hardirqs_on() before enabling irqs
ARC: use correct offset in pt_regs for saving/restoring user mode r25
ARC: build: Better way to detect ISA compatible toolchain
drm/i915: fix aliasing_ppgtt leak
drm/amdgpu: record error code when ring test failed
drm/amd/amdgpu: sdma resume fail during S4 on CI
drm/amdgpu: skip TV/CV in display parsing
drm/amdgpu: avoid a possible array overflow
drm/amdgpu: fix amdgpu_move_blit on 32bit systems
drm/amdgpu: Change GART offset to 64-bit
iio: fix sched WARNING "do not call blocking ops when !TASK_RUNNING"
sched/nohz: Fix affine unpinned timers mess
sched/cputime: Fix NO_HZ_FULL getrusage() monotonicity regression
of: fix reference counting in of_graph_get_endpoint_by_regs
arm64: dts: rockchip: add reset saradc node for rk3368 SoCs
mac80211: fix purging multicast PS buffer queue
s390/dasd: fix hanging device after clear subchannel
EDAC: Increment correct counter in edac_inc_ue_error()
pinctrl/amd: Remove the default de-bounce time
iommu/arm-smmu: Don't BUG() if we find aborting STEs with disable_bypass
iommu/arm-smmu: Fix CMDQ error handling
iommu/dma: Don't put uninitialised IOVA domains
xhci: Make sure xhci handles USB_SPEED_SUPER_PLUS devices.
USB: serial: ftdi_sio: add PIDs for Ivium Technologies devices
USB: serial: ftdi_sio: add device ID for WICED USB UART dev board
USB: serial: option: add support for Telit LE920A4
USB: serial: option: add D-Link DWM-156/A3
USB: serial: fix memleak in driver-registration error path
xhci: don't dereference a xhci member after removing xhci
usb: xhci: Fix panic if disconnect
xhci: always handle "Command Ring Stopped" events
usb/gadget: fix gadgetfs aio support.
usb: gadget: fsl_qe_udc: off by one in setup_received_handle()
USB: validate wMaxPacketValue entries in endpoint descriptors
usb: renesas_usbhs: Use dmac only if the pipe type is bulk
usb: renesas_usbhs: clear the BRDYSTS in usbhsg_ep_enable()
USB: hub: change the locking in hub_activate
USB: hub: fix up early-exit pathway in hub_activate
usb: hub: Fix unbalanced reference count/memory leak/deadlocks
usb: define USB_SPEED_SUPER_PLUS speed for SuperSpeedPlus USB3.1 devices
usb: dwc3: gadget: increment request->actual once
usb: dwc3: pci: add Intel Kabylake PCI ID
usb: misc: usbtest: add fix for driver hang
usb: ehci: change order of register cleanup during shutdown
crypto: caam - defer aead_set_sh_desc in case of zero authsize
crypto: caam - fix echainiv(authenc) encrypt shared descriptor
crypto: caam - fix non-hmac hashes
genirq/msi: Make sure PCI MSIs are activated early
genirq/msi: Remove unused MSI_FLAG_IDENTITY_MAP
um: Don't discard .text.exit section
ACPI / CPPC: Prevent cpc_desc_ptr points to the invalid data
ACPI: CPPC: Return error if _CPC is invalid on a CPU
mmc: sdhci-acpi: Reduce Baytrail eMMC/SD/SDIO hangs
PCI: Limit config space size for Netronome NFP4000
PCI: Add Netronome NFP4000 PF device ID
PCI: Limit config space size for Netronome NFP6000 family
PCI: Add Netronome vendor and device IDs
PCI: Support PCIe devices with short cfg_size
NVMe: Don't unmap controller registers on reset
ALSA: hda - Manage power well properly for resume
libnvdimm, nd_blk: mask off reserved status bits
perf intel-pt: Fix occasional decoding errors when tracing system-wide
vfio/pci: Fix NULL pointer oops in error interrupt setup handling
virtio: fix memory leak in virtqueue_add()
parisc: Fix order of EREFUSED define in errno.h
arm64: Define AT_VECTOR_SIZE_ARCH for ARCH_DLINFO
ALSA: usb-audio: Add quirk for ELP HD USB Camera
ALSA: usb-audio: Add a sample rate quirk for Creative Live! Cam Socialize HD (VF0610)
powerpc/eeh: eeh_pci_enable(): fix checking of post-request state
SUNRPC: allow for upcalls for same uid but different gss service
SUNRPC: Handle EADDRNOTAVAIL on connection failures
tools/testing/nvdimm: fix SIGTERM vs hotplug crash
uprobes/x86: Fix RIP-relative handling of EVEX-encoded instructions
x86/mm: Disable preemption during CR3 read+write
hugetlb: fix nr_pmds accounting with shared page tables
mm: SLUB hardened usercopy support
mm: SLAB hardened usercopy support
s390/uaccess: Enable hardened usercopy
sparc/uaccess: Enable hardened usercopy
powerpc/uaccess: Enable hardened usercopy
ia64/uaccess: Enable hardened usercopy
arm64/uaccess: Enable hardened usercopy
ARM: uaccess: Enable hardened usercopy
x86/uaccess: Enable hardened usercopy
x86: remove more uaccess_32.h complexity
x86: remove pointless uaccess_32.h complexity
x86: fix SMAP in 32-bit environments
Use the new batched user accesses in generic user string handling
Add 'unsafe' user access functions for batched accesses
x86: reorganize SMAP handling in user space accesses
mm: Hardened usercopy
mm: Implement stack frame object validation
mm: Add is_migrate_cma_page
Linux 4.4.19
Documentation/module-signing.txt: Note need for version info if reusing a key
module: Invalidate signatures on force-loaded modules
dm flakey: error READ bios during the down_interval
rtc: s3c: Add s3c_rtc_{enable/disable}_clk in s3c_rtc_setfreq()
lpfc: fix oops in lpfc_sli4_scmd_to_wqidx_distr() from lpfc_send_taskmgmt()
ACPI / EC: Work around method reentrancy limit in ACPICA for _Qxx
x86/platform/intel_mid_pci: Rework IRQ0 workaround
PCI: Mark Atheros AR9485 and QCA9882 to avoid bus reset
MIPS: hpet: Increase HPET_MIN_PROG_DELTA and decrease HPET_MIN_CYCLES
MIPS: Don't register r4k sched clock when CPUFREQ enabled
MIPS: mm: Fix definition of R6 cache instruction
SUNRPC: Don't allocate a full sockaddr_storage for tracing
Input: elan_i2c - properly wake up touchpad on ASUS laptops
target: Fix ordered task CHECK_CONDITION early exception handling
target: Fix max_unmap_lba_count calc overflow
target: Fix race between iscsi-target connection shutdown + ABORT_TASK
target: Fix missing complete during ABORT_TASK + CMD_T_FABRIC_STOP
target: Fix ordered task target_setup_cmd_from_cdb exception hang
iscsi-target: Fix panic when adding second TCP connection to iSCSI session
ubi: Fix race condition between ubi device creation and udev
ubi: Fix early logging
ubi: Make volume resize power cut aware
of: fix memory leak related to safe_name()
IB/mlx4: Fix memory leak if QP creation failed
IB/mlx4: Fix error flow when sending mads under SRIOV
IB/mlx4: Fix the SQ size of an RC QP
IB/IWPM: Fix a potential skb leak
IB/IPoIB: Don't update neigh validity for unresolved entries
IB/SA: Use correct free function
IB/mlx5: Return PORT_ERR in Active to Initializing tranisition
IB/mlx5: Fix post send fence logic
IB/mlx5: Fix entries check in mlx5_ib_resize_cq
IB/mlx5: Fix returned values of query QP
IB/mlx5: Fix entries checks in mlx5_ib_create_cq
IB/mlx5: Fix MODIFY_QP command input structure
ALSA: hda - Fix headset mic detection problem for two dell machines
ALSA: hda: add AMD Bonaire AZ PCI ID with proper driver caps
ALSA: hda/realtek - Can't adjust speaker's volume on a Dell AIO
ALSA: hda: Fix krealloc() with __GFP_ZERO usage
mm/hugetlb: avoid soft lockup in set_max_huge_pages()
mtd: nand: fix bug writing 1 byte less than page size
block: fix bdi vs gendisk lifetime mismatch
block: add missing group association in bio-cloning functions
metag: Fix __cmpxchg_u32 asm constraint for CMP
ftrace/recordmcount: Work around for addition of metag magic but not relocations
balloon: check the number of available pages in leak balloon
drm/i915/dp: Revert "drm/i915/dp: fall back to 18 bpp when sink capability is unknown"
drm/i915: Never fully mask the the EI up rps interrupt on SNB/IVB
drm/edid: Add 6 bpc quirk for display AEO model 0.
drm: Restore double clflush on the last partial cacheline
drm/nouveau/fbcon: fix font width not divisible by 8
drm/nouveau/gr/nv3x: fix instobj write offsets in gr setup
drm/nouveau: check for supported chipset before booting fbdev off the hw
drm/radeon: support backlight control for UNIPHY3
drm/radeon: fix firmware info version checks
drm/radeon: Poll for both connect/disconnect on analog connectors
drm/radeon: add a delay after ATPX dGPU power off
drm/amdgpu/gmc7: add missing mullins case
drm/amdgpu: fix firmware info version checks
drm/amdgpu: Disable RPM helpers while reprobing connectors on resume
drm/amdgpu: support backlight control for UNIPHY3
drm/amdgpu: Poll for both connect/disconnect on analog connectors
drm/amdgpu: add a delay after ATPX dGPU power off
w1:omap_hdq: fix regression
netlabel: add address family checks to netlbl_{sock,req}_delattr()
ARM: dts: sunxi: Add a startup delay for fixed regulator enabled phys
audit: fix a double fetch in audit_log_single_execve_arg()
iommu/amd: Update Alias-DTE in update_device_table()
iommu/amd: Init unity mappings only for dma_ops domains
iommu/amd: Handle IOMMU_DOMAIN_DMA in ops->domain_free call-back
iommu/vt-d: Return error code in domain_context_mapping_one()
iommu/exynos: Suppress unbinding to prevent system failure
drm/i915: Don't complain about lack of ACPI video bios
nfsd: don't return an unhashed lock stateid after taking mutex
nfsd: Fix race between FREE_STATEID and LOCK
nfs: don't create zero-length requests
MIPS: KVM: Propagate kseg0/mapped tlb fault errors
MIPS: KVM: Fix gfn range check in kseg0 tlb faults
MIPS: KVM: Add missing gfn range check
MIPS: KVM: Fix mapped fault broken commpage handling
random: add interrupt callback to VMBus IRQ handler
random: print a warning for the first ten uninitialized random users
random: initialize the non-blocking pool via add_hwgenerator_randomness()
CIFS: Fix a possible invalid memory access in smb2_query_symlink()
cifs: fix crash due to race in hmac(md5) handling
cifs: Check for existing directory when opening file with O_CREAT
fs/cifs: make share unaccessible at root level mountable
jbd2: make journal y2038 safe
ARC: mm: don't loose PTE_SPECIAL in pte_modify()
remoteproc: Fix potential race condition in rproc_add
ovl: disallow overlayfs as upperdir
HID: uhid: fix timeout when probe races with IO
EDAC: Correct channel count limit
Bluetooth: Fix l2cap_sock_setsockopt() with optname BT_RCVMTU
spi: pxa2xx: Clear all RFT bits in reset_sccr1() on Intel Quark
i2c: efm32: fix a failure path in efm32_i2c_probe()
s5p-mfc: Add release callback for memory region devs
s5p-mfc: Set device name for reserved memory region devs
hp-wmi: Fix wifi cannot be hard-unblocked
dm: set DMF_SUSPENDED* _before_ clearing DMF_NOFLUSH_SUSPENDING
sur40: fix occasional oopses on device close
sur40: lower poll interval to fix occasional FPS drops to ~56 FPS
Fix RC5 decoding with Fintek CIR chipset
vb2: core: Skip planes array verification if pb is NULL
videobuf2-v4l2: Verify planes array in buffer dequeueing
media: dvb_ringbuffer: Add memory barriers
media: usbtv: prevent access to free'd resources
mfd: qcom_rpm: Parametrize also ack selector size
mfd: qcom_rpm: Fix offset error for msm8660
intel_pstate: Fix MSR_CONFIG_TDP_x addressing in core_get_max_pstate()
s390/cio: allow to reset channel measurement block
KVM: nVMX: Fix memory corruption when using VMCS shadowing
KVM: VMX: handle PML full VMEXIT that occurs during event delivery
KVM: MTRR: fix kvm_mtrr_check_gfn_range_consistency page fault
KVM: PPC: Book3S HV: Save/restore TM state in H_CEDE
KVM: PPC: Book3S HV: Pull out TM state save/restore into separate procedures
arm64: mm: avoid fdt_check_header() before the FDT is fully mapped
arm64: dts: rockchip: fixes the gic400 2nd region size for rk3368
pinctrl: cherryview: prevent concurrent access to GPIO controllers
Bluetooth: hci_intel: Fix null gpio desc pointer dereference
gpio: intel-mid: Remove potentially harmful code
gpio: pca953x: Fix NBANK calculation for PCA9536
tty/serial: atmel: fix RS485 half duplex with DMA
serial: samsung: Fix ERR pointer dereference on deferred probe
tty: serial: msm: Don't read off end of tx fifo
arm64: Fix incorrect per-cpu usage for boot CPU
arm64: debug: unmask PSTATE.D earlier
arm64: kernel: Save and restore UAO and addr_limit on exception entry
USB: usbfs: fix potential infoleak in devio
usb: renesas_usbhs: fix NULL pointer dereference in xfer_work()
USB: serial: option: add support for Telit LE910 PID 0x1206
usb: dwc3: fix for the isoc transfer EP_BUSY flag
usb: quirks: Add no-lpm quirk for Elan
usb: renesas_usbhs: protect the CFIFOSEL setting in usbhsg_ep_enable()
usb: f_fs: off by one bug in _ffs_func_bind()
usb: gadget: avoid exposing kernel stack
UPSTREAM: usb: gadget: configfs: add mutex lock before unregister gadget
ANDROID: dm-verity: adopt changes made to dm callbacks
UPSTREAM: ecryptfs: fix handling of directory opening
ANDROID: net: core: fix UID-based routing
ANDROID: net: fib: remove duplicate assignment
FROMLIST: proc: Fix timerslack_ns CAP_SYS_NICE check when adjusting self
ANDROID: dm verity fec: pack the fec_header structure
ANDROID: dm: android-verity: Verify header before fetching table
ANDROID: dm: allow adb disable-verity only in userdebug
ANDROID: dm: mount as linear target if eng build
ANDROID: dm: use default verity public key
ANDROID: dm: fix signature verification flag
ANDROID: dm: use name_to_dev_t
ANDROID: dm: rename dm-linear methods for dm-android-verity
ANDROID: dm: Minor cleanup
ANDROID: dm: Mounting root as linear device when verity disabled
ANDROID: dm-android-verity: Rebase on top of 4.1
ANDROID: dm: Add android verity target
ANDROID: dm: fix dm_substitute_devices()
ANDROID: dm: Rebase on top of 4.1
CHROMIUM: dm: boot time specification of dm=
Implement memory_state_time, used by qcom,cpubw
Revert "panic: Add board ID to panic output"
usb: gadget: f_accessory: remove duplicate endpoint alloc
BACKPORT: brcmfmac: defer DPC processing during probe
FROMLIST: proc: Add LSM hook checks to /proc/<tid>/timerslack_ns
FROMLIST: proc: Relax /proc/<tid>/timerslack_ns capability requirements
UPSTREAM: ppp: defer netns reference release for ppp channel
cpuset: Add allow_attach hook for cpusets on android.
UPSTREAM: KEYS: Fix ASN.1 indefinite length object parsing
ANDROID: sdcardfs: fix itnull.cocci warnings
android-recommended.cfg: enable fstack-protector-strong
Linux 4.4.18
mm: memcontrol: fix memcg id ref counter on swap charge move
mm: memcontrol: fix swap counter leak on swapout from offline cgroup
mm: memcontrol: fix cgroup creation failure after many small jobs
ext4: fix reference counting bug on block allocation error
ext4: short-cut orphan cleanup on error
ext4: validate s_reserved_gdt_blocks on mount
ext4: don't call ext4_should_journal_data() on the journal inode
ext4: fix deadlock during page writeback
ext4: check for extents that wrap around
crypto: scatterwalk - Fix test in scatterwalk_done
crypto: gcm - Filter out async ghash if necessary
fs/dcache.c: avoid soft-lockup in dput()
fuse: fix wrong assignment of ->flags in fuse_send_init()
fuse: fuse_flush must check mapping->flags for errors
fuse: fsync() did not return IO errors
sysv, ipc: fix security-layer leaking
block: fix use-after-free in seq file
x86/syscalls/64: Add compat_sys_keyctl for 32-bit userspace
drm/i915: Pretend cursor is always on for ILK-style WM calculations (v2)
x86/mm/pat: Fix BUG_ON() in mmap_mem() on QEMU/i386
x86/pat: Document the PAT initialization sequence
x86/xen, pat: Remove PAT table init code from Xen
x86/mtrr: Fix PAT init handling when MTRR is disabled
x86/mtrr: Fix Xorg crashes in Qemu sessions
x86/mm/pat: Replace cpu_has_pat with boot_cpu_has()
x86/mm/pat: Add pat_disable() interface
x86/mm/pat: Add support of non-default PAT MSR setting
devpts: clean up interface to pty drivers
random: strengthen input validation for RNDADDTOENTCNT
apparmor: fix ref count leak when profile sha1 hash is read
Revert "s390/kdump: Clear subchannel ID to signal non-CCW/SCSI IPL"
KEYS: 64-bit MIPS needs to use compat_sys_keyctl for 32-bit userspace
arm: oabi compat: add missing access checks
cdc_ncm: do not call usbnet_link_change from cdc_ncm_bind
i2c: i801: Allow ACPI SystemIO OpRegion to conflict with PCI BAR
x86/mm/32: Enable full randomization on i386 and X86_32
HID: sony: do not bail out when the sixaxis refuses the output report
PNP: Add Broadwell to Intel MCH size workaround
PNP: Add Haswell-ULT to Intel MCH size workaround
scsi: ignore errors from scsi_dh_add_device()
ipath: Restrict use of the write() interface
tcp: consider recv buf for the initial window scale
qed: Fix setting/clearing bit in completion bitmap
net/irda: fix NULL pointer dereference on memory allocation failure
net: bgmac: Fix infinite loop in bgmac_dma_tx_add()
bonding: set carrier off for devices created through netlink
ipv4: reject RTNH_F_DEAD and RTNH_F_LINKDOWN from user space
tcp: enable per-socket rate limiting of all 'challenge acks'
tcp: make challenge acks less predictable
arm64: relocatable: suppress R_AARCH64_ABS64 relocations in vmlinux
arm64: vmlinux.lds: make __rela_offset and __dynsym_offset ABSOLUTE
Linux 4.4.17
vfs: fix deadlock in file_remove_privs() on overlayfs
intel_th: Fix a deadlock in modprobing
intel_th: pci: Add Kaby Lake PCH-H support
net: mvneta: set real interrupt per packet for tx_done
libceph: apply new_state before new_up_client on incrementals
libata: LITE-ON CX1-JB256-HP needs lower max_sectors
i2c: mux: reg: wrong condition checked for of_address_to_resource return value
posix_cpu_timer: Exit early when process has been reaped
media: fix airspy usb probe error path
ipr: Clear interrupt on croc/crocodile when running with LSI
SCSI: fix new bug in scsi_dev_info_list string matching
RDS: fix rds_tcp_init() error path
can: fix oops caused by wrong rtnl dellink usage
can: fix handling of unmodifiable configuration options fix
can: c_can: Update D_CAN TX and RX functions to 32 bit - fix Altera Cyclone access
can: at91_can: RX queue could get stuck at high bus load
perf/x86: fix PEBS issues on Intel Atom/Core2
ovl: handle ATTR_KILL*
sched/fair: Fix effective_load() to consistently use smoothed load
mmc: block: fix packed command header endianness
block: fix use-after-free in sys_ioprio_get()
qeth: delete napi struct when removing a qeth device
platform/chrome: cros_ec_dev - double fetch bug in ioctl
clk: rockchip: initialize flags of clk_init_data in mmc-phase clock
spi: sun4i: fix FIFO limit
spi: sunxi: fix transfer timeout
namespace: update event counter when umounting a deleted dentry
9p: use file_dentry()
ext4: verify extent header depth
ecryptfs: don't allow mmap when the lower fs doesn't support it
Revert "ecryptfs: forbid opening files without mmap handler"
locks: use file_inode()
power_supply: power_supply_read_temp only if use_cnt > 0
cgroup: set css->id to -1 during init
pinctrl: imx: Do not treat a PIN without MUX register as an error
pinctrl: single: Fix missing flush of posted write for a wakeirq
pvclock: Add CPU barriers to get correct version value
Input: tsc200x - report proper input_dev name
Input: xpad - validate USB endpoint count during probe
Input: wacom_w8001 - w8001_MAX_LENGTH should be 13
Input: xpad - fix oops when attaching an unknown Xbox One gamepad
Input: elantech - add more IC body types to the list
Input: vmmouse - remove port reservation
ALSA: timer: Fix leak in events via snd_timer_user_tinterrupt
ALSA: timer: Fix leak in events via snd_timer_user_ccallback
ALSA: timer: Fix leak in SNDRV_TIMER_IOCTL_PARAMS
xenbus: don't bail early from xenbus_dev_request_and_reply()
xenbus: don't BUG() on user mode induced condition
xen/pciback: Fix conf_space read/write overlap check.
ARC: unwind: ensure that .debug_frame is generated (vs. .eh_frame)
arc: unwind: warn only once if DW2_UNWIND is disabled
kernel/sysrq, watchdog, sched/core: Reset watchdog on all CPUs while processing sysrq-w
pps: do not crash when failed to register
vmlinux.lds: account for destructor sections
mm, meminit: ensure node is online before checking whether pages are uninitialised
mm, meminit: always return a valid node from early_pfn_to_nid
mm, compaction: prevent VM_BUG_ON when terminating freeing scanner
fs/nilfs2: fix potential underflow in call to crc32_le
mm, compaction: abort free scanner if split fails
mm, sl[au]b: add __GFP_ATOMIC to the GFP reclaim mask
dmaengine: at_xdmac: double FIFO flush needed to compute residue
dmaengine: at_xdmac: fix residue corruption
dmaengine: at_xdmac: align descriptors on 64 bits
x86/quirks: Add early quirk to reset Apple AirPort card
x86/quirks: Reintroduce scanning of secondary buses
x86/quirks: Apply nvidia_bugs quirk only on root bus
USB: OHCI: Don't mark EDs as ED_OPER if scheduling fails
Conflicts:
arch/arm/kernel/topology.c
arch/arm64/include/asm/arch_gicv3.h
arch/arm64/kernel/topology.c
block/bio.c
drivers/cpufreq/Kconfig
drivers/md/Makefile
drivers/media/dvb-core/dvb_ringbuffer.c
drivers/media/tuners/tuner-xc2028.c
drivers/misc/Kconfig
drivers/misc/Makefile
drivers/mmc/core/host.c
drivers/scsi/ufs/ufshcd.c
drivers/scsi/ufs/ufshcd.h
drivers/usb/dwc3/gadget.c
drivers/usb/gadget/configfs.c
fs/ecryptfs/file.c
include/linux/mmc/core.h
include/linux/mmc/host.h
include/linux/mmzone.h
include/linux/sched.h
include/linux/sched/sysctl.h
include/trace/events/power.h
include/trace/events/sched.h
init/Kconfig
kernel/cpuset.c
kernel/exit.c
kernel/sched/Makefile
kernel/sched/core.c
kernel/sched/cputime.c
kernel/sched/fair.c
kernel/sched/features.h
kernel/sched/rt.c
kernel/sched/sched.h
kernel/sched/stop_task.c
kernel/sched/tune.c
lib/Kconfig.debug
mm/Makefile
mm/vmstat.c
Change-Id: I243a43231ca56a6362076fa6301827e1b0493be5
Signed-off-by: Runmin Wang <runminw@codeaurora.org>
Right now the vmpressure window is of constant size 2MB, which
works well with the following exceptions.
1) False vmpressure triggers are seen when the RAM size is greater
than 3GB. This results in lowmemorykiller, which uses vmpressure
events, killing tasks unnecessarily.
2) Vmpressure events are received late under memory pressure. This
behaviour is seen prominently in <=2GB RAM targets. This results in
lowmemorykiller kicking in late to kill tasks resulting in avoidable
page cache reclaim.
The problem analysis shows that the issue is with the constant size
of the vmpressure window which does not adapt to the varying memory
conditions. This patch recalculates the vmpressure window size at
the end of each window. The chosen window size is proportional to
the total of free and cached memory at that point.
Change-Id: I7e9ef4ddd82e2c2dd04ce09ec8d58a8829cfb64d
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
This is an ancient bug that was actually attempted to be fixed once
(badly) by me eleven years ago in commit 4ceb5db975 ("Fix
get_user_pages() race for write access") but that was then undone due to
problems on s390 by commit f33ea7f404 ("fix get_user_pages bug").
In the meantime, the s390 situation has long been fixed, and we can now
fix it by checking the pte_dirty() bit properly (and do it better). The
s390 dirty bit was implemented in abf09bed3c ("s390/mm: implement
software dirty bits") which made it into v3.9. Earlier kernels will
have to look at the page state itself.
Also, the VM has become more scalable, and what used a purely
theoretical race back then has become easier to trigger.
To fix it, we introduce a new internal FOLL_COW flag to mark the "yes,
we already did a COW" rather than play racy games with FOLL_WRITE that
is very fundamental, and then use the pte dirty flag to validate that
the FOLL_COW flag is still valid.
Change-Id: I42e448ecacad4781b460c4c989026307169ba1b5
Reported-and-tested-by: Phil "not Paul" Oester <kernel@linuxace.com>
Acked-by: Hugh Dickins <hughd@google.com>
Reviewed-by: Michal Hocko <mhocko@suse.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Nick Piggin <npiggin@gmail.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-repo: https://chromium.googlesource.com/chromiumos/third_party/kernel.git
Git-commit: 19be0eaffa3ac7d8eb6784ad9bdbc7d67ed8e619
Signed-off-by: Dennis Cagle <d-cagle@codeaurora.org>
kasan_alloc_pages() should be called alongside kernel_map_pages() to
prevent splats when CONFIG_KASAN is enabled.
This is a greatly simplified version of
commit 46f24fd857b37bb86ddd5d0ac3d194e984dfdf1c
("mm/page_alloc: introduce post allocation processing on page allocator")
which solve the same problem on later kernel versions.
Change-Id: Ib60d079a4d8685e781624bb1403b2a3060e31d27
Signed-off-by: Patrick Daly <pdaly@codeaurora.org>
CMA allocation request size is represented by size_t that
gets truncated when same is passed as int to
bitmap_find_next_zero_area_off.
We observe that during fuzz testing when cma allocation
request is too high, bitmap_find_next_zero_area_off still
returns success due to the truncation. This leads to
kernel crash, as subsequent code assumes that requested
memory is available.
Fail cma allocation in case the request breaches the
corresponding cma region size.
Change-Id: Ieb5fd8429726efd7686387bccb55952fb053280a
Signed-off-by: Shiraz Hashim <shashim@codeaurora.org>
Linux Build Service Account
Minchan Kim
Sergey Senozhatsky
YiPing Xu
Weijie Yang
Chen Feng
Vlastimil Babka
Vinayak Menon
Suyog Sarda
Runmin Wang
Linus Torvalds
Patrick Daly
Shiraz Hashim