21 Sep, 2020
1 commit
-
Linux 5.9-rc6
Signed-off-by: Greg Kroah-Hartman
Change-Id: I3bccdbb773bfc2c604742e6ff5983bf0b61ba0b5
20 Sep, 2020
1 commit
-
5.8 commit 5d91f31faf8e ("mm: swap: fix vmstats for huge page") has
established that vm_events should count every subpage of a THP, including
unevictable_pgs_culled and unevictable_pgs_rescued; but
lru_cache_add_inactive_or_unevictable() was not doing so for
unevictable_pgs_mlocked, and mm/mlock.c was not doing so for
unevictable_pgs mlocked, munlocked, cleared and stranded.Fix them; but THPs don't go the pagevec way in mlock.c, so no fixes needed
on that path.Fixes: 5d91f31faf8e ("mm: swap: fix vmstats for huge page")
Signed-off-by: Hugh Dickins
Signed-off-by: Andrew Morton
Reviewed-by: Shakeel Butt
Acked-by: Yang Shi
Cc: Alex Shi
Cc: Johannes Weiner
Cc: Michal Hocko
Cc: Mike Kravetz
Cc: Qian Cai
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2008301408230.5954@eggly.anvils
Signed-off-by: Linus Torvalds
17 Aug, 2020
1 commit
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…ux-block") into android-mainline
Steps on the way to 5.9-rc1
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I904678b5c31139b25fb49ee67cbacb4721a3c7bc
15 Aug, 2020
1 commit
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The thp prefix is more frequently used than hpage and we should be
consistent between the various functions.[akpm@linux-foundation.org: fix mm/migrate.c]
Signed-off-by: Matthew Wilcox (Oracle)
Signed-off-by: Andrew Morton
Reviewed-by: William Kucharski
Reviewed-by: Zi Yan
Cc: Mike Kravetz
Cc: David Hildenbrand
Cc: "Kirill A. Shutemov"
Link: http://lkml.kernel.org/r/20200629151959.15779-6-willy@infradead.org
Signed-off-by: Linus Torvalds
24 Jun, 2020
1 commit
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…cm/linux/kernel/git/linkinjeon/exfat") into android-mainline
Steps on the way to 5.8-rc1.
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I4bc42f572167ea2f815688b4d1eb6124b6d260d4
10 Jun, 2020
2 commits
-
Convert comments that reference mmap_sem to reference mmap_lock instead.
[akpm@linux-foundation.org: fix up linux-next leftovers]
[akpm@linux-foundation.org: s/lockaphore/lock/, per Vlastimil]
[akpm@linux-foundation.org: more linux-next fixups, per Michel]Signed-off-by: Michel Lespinasse
Signed-off-by: Andrew Morton
Reviewed-by: Vlastimil Babka
Reviewed-by: Daniel Jordan
Cc: Davidlohr Bueso
Cc: David Rientjes
Cc: Hugh Dickins
Cc: Jason Gunthorpe
Cc: Jerome Glisse
Cc: John Hubbard
Cc: Laurent Dufour
Cc: Liam Howlett
Cc: Matthew Wilcox
Cc: Peter Zijlstra
Cc: Ying Han
Link: http://lkml.kernel.org/r/20200520052908.204642-13-walken@google.com
Signed-off-by: Linus Torvalds -
This change converts the existing mmap_sem rwsem calls to use the new mmap
locking API instead.The change is generated using coccinelle with the following rule:
// spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir .
@@
expression mm;
@@
(
-init_rwsem
+mmap_init_lock
|
-down_write
+mmap_write_lock
|
-down_write_killable
+mmap_write_lock_killable
|
-down_write_trylock
+mmap_write_trylock
|
-up_write
+mmap_write_unlock
|
-downgrade_write
+mmap_write_downgrade
|
-down_read
+mmap_read_lock
|
-down_read_killable
+mmap_read_lock_killable
|
-down_read_trylock
+mmap_read_trylock
|
-up_read
+mmap_read_unlock
)
-(&mm->mmap_sem)
+(mm)Signed-off-by: Michel Lespinasse
Signed-off-by: Andrew Morton
Reviewed-by: Daniel Jordan
Reviewed-by: Laurent Dufour
Reviewed-by: Vlastimil Babka
Cc: Davidlohr Bueso
Cc: David Rientjes
Cc: Hugh Dickins
Cc: Jason Gunthorpe
Cc: Jerome Glisse
Cc: John Hubbard
Cc: Liam Howlett
Cc: Matthew Wilcox
Cc: Peter Zijlstra
Cc: Ying Han
Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com
Signed-off-by: Linus Torvalds
02 Oct, 2019
1 commit
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To make the 5.4-rc1 merge easier, merge at a prerelease point in time
before the final release happens.Signed-off-by: Greg Kroah-Hartman
Change-Id: If613d657fd0abf9910c5bf3435a745f01b89765e
26 Sep, 2019
1 commit
-
This patch is a part of a series that extends kernel ABI to allow to pass
tagged user pointers (with the top byte set to something else other than
0x00) as syscall arguments.This patch allows tagged pointers to be passed to the following memory
syscalls: get_mempolicy, madvise, mbind, mincore, mlock, mlock2, mprotect,
mremap, msync, munlock, move_pages.The mmap and mremap syscalls do not currently accept tagged addresses.
Architectures may interpret the tag as a background colour for the
corresponding vma.Link: http://lkml.kernel.org/r/aaf0c0969d46b2feb9017f3e1b3ef3970b633d91.1563904656.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov
Reviewed-by: Khalid Aziz
Reviewed-by: Vincenzo Frascino
Reviewed-by: Catalin Marinas
Reviewed-by: Kees Cook
Cc: Al Viro
Cc: Dave Hansen
Cc: Eric Auger
Cc: Felix Kuehling
Cc: Jens Wiklander
Cc: Mauro Carvalho Chehab
Cc: Mike Rapoport
Cc: Will Deacon
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
17 Jun, 2019
1 commit
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Linux 5.2-rc5
Signed-off-by: Greg Kroah-Hartman
14 Jun, 2019
2 commits
-
On a 64-bit machine the value of "vma->vm_end - vma->vm_start" may be
negative when using 32 bit ints and the "count >> PAGE_SHIFT"'s result
will be wrong. So change the local variable and return value to
unsigned long to fix the problem.Link: http://lkml.kernel.org/r/20190513023701.83056-1-swkhack@gmail.com
Fixes: 0cf2f6f6dc60 ("mm: mlock: check against vma for actual mlock() size")
Signed-off-by: swkhack
Acked-by: Michal Hocko
Reviewed-by: Andrew Morton
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
If mlockall() is called with only MCL_ONFAULT as flag, it removes any
previously applied lockings and does nothing else.This behavior is counter-intuitive and doesn't match the Linux man page.
For mlockall():
EINVAL Unknown flags were specified or MCL_ONFAULT was specified
without either MCL_FUTURE or MCL_CURRENT.Consequently, return the error EINVAL, if only MCL_ONFAULT is passed.
That way, applications will at least detect that they are calling
mlockall() incorrectly.Link: http://lkml.kernel.org/r/20190527075333.GA6339@er01809n.ebgroup.elektrobit.com
Fixes: b0f205c2a308 ("mm: mlock: add mlock flags to enable VM_LOCKONFAULT usage")
Signed-off-by: Stefan Potyra
Reviewed-by: Daniel Jordan
Acked-by: Michal Hocko
Acked-by: Vlastimil Babka
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
04 May, 2019
2 commits
-
Change-Id: I4380c68c3474026a42ffa9f95c525f9a563ba7a3
-
Userspace processes often have multiple allocators that each do
anonymous mmaps to get memory. When examining memory usage of
individual processes or systems as a whole, it is useful to be
able to break down the various heaps that were allocated by
each layer and examine their size, RSS, and physical memory
usage.This patch adds a user pointer to the shared union in
vm_area_struct that points to a null terminated string inside
the user process containing a name for the vma. vmas that
point to the same address will be merged, but vmas that
point to equivalent strings at different addresses will
not be merged.Userspace can set the name for a region of memory by calling
prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, start, len, (unsigned long)name);
Setting the name to NULL clears it.The names of named anonymous vmas are shown in /proc/pid/maps
as [anon:] and in /proc/pid/smaps in a new "Name" field
that is only present for named vmas. If the userspace pointer
is no longer valid all or part of the name will be replaced
with "".The idea to store a userspace pointer to reduce the complexity
within mm (at the expense of the complexity of reading
/proc/pid/mem) came from Dave Hansen. This results in no
runtime overhead in the mm subsystem other than comparing
the anon_name pointers when considering vma merging. The pointer
is stored in a union with fieds that are only used on file-backed
mappings, so it does not increase memory usage.Includes fix from Jed Davis for typo in
prctl_set_vma_anon_name, which could attempt to set the name
across two vmas at the same time due to a typo, which might
corrupt the vma list. Fix it to use tmp instead of end to limit
the name setting to a single vma at a time.Bug: 120441514
Change-Id: I9aa7b6b5ef536cd780599ba4e2fba8ceebe8b59f
Signed-off-by: Dmitry Shmidt
[AmitP: Fix get_user_pages_remote() call to align with upstream commit
5b56d49fc31d ("mm: add locked parameter to get_user_pages_remote()")]
Signed-off-by: Amit Pundir
06 Mar, 2019
1 commit
-
We have common pattern to access lru_lock from a page pointer:
zone_lru_lock(page_zone(page))Which is silly, because it unfolds to this:
&NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)]->zone_pgdat->lru_lock
while we can simply do
&NODE_DATA(page_to_nid(page))->lru_lockRemove zone_lru_lock() function, since it's only complicate things. Use
'page_pgdat(page)->lru_lock' pattern instead.[aryabinin@virtuozzo.com: a slightly better version of __split_huge_page()]
Link: http://lkml.kernel.org/r/20190301121651.7741-1-aryabinin@virtuozzo.com
Link: http://lkml.kernel.org/r/20190228083329.31892-2-aryabinin@virtuozzo.com
Signed-off-by: Andrey Ryabinin
Acked-by: Vlastimil Babka
Acked-by: Mel Gorman
Cc: Johannes Weiner
Cc: Michal Hocko
Cc: Rik van Riel
Cc: William Kucharski
Cc: John Hubbard
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
18 Aug, 2018
1 commit
-
This patch is reworked from an earlier patch that Dan has posted:
https://patchwork.kernel.org/patch/10131727/VM_MIXEDMAP is used by dax to direct mm paths like vm_normal_page() that
the memory page it is dealing with is not typical memory from the linear
map. The get_user_pages_fast() path, since it does not resolve the vma,
is already using {pte,pmd}_devmap() as a stand-in for VM_MIXEDMAP, so we
use that as a VM_MIXEDMAP replacement in some locations. In the cases
where there is no pte to consult we fallback to using vma_is_dax() to
detect the VM_MIXEDMAP special case.Now that we have explicit driver pfn_t-flag opt-in/opt-out for
get_user_pages() support for DAX we can stop setting VM_MIXEDMAP. This
also means we no longer need to worry about safely manipulating vm_flags
in a future where we support dynamically changing the dax mode of a
file.DAX should also now be supported with madvise_behavior(), vma_merge(),
and copy_page_range().This patch has been tested against ndctl unit test. It has also been
tested against xfstests commit: 625515d using fake pmem created by
memmap and no additional issues have been observed.Link: http://lkml.kernel.org/r/152847720311.55924.16999195879201817653.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Dave Jiang
Acked-by: Dan Williams
Cc: Jan Kara
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
22 Feb, 2018
1 commit
-
When a thread mlocks an address space backed either by file pages which
are currently not present in memory or swapped out anon pages (not in
swapcache), a new page is allocated and added to the local pagevec
(lru_add_pvec), I/O is triggered and the thread then sleeps on the page.
On I/O completion, the thread can wake on a different CPU, the mlock
syscall will then sets the PageMlocked() bit of the page but will not be
able to put that page in unevictable LRU as the page is on the pagevec
of a different CPU. Even on drain, that page will go to evictable LRU
because the PageMlocked() bit is not checked on pagevec drain.The page will eventually go to right LRU on reclaim but the LRU stats
will remain skewed for a long time.This patch puts all the pages, even unevictable, to the pagevecs and on
the drain, the pages will be added on their LRUs correctly by checking
their evictability. This resolves the mlocked pages on pagevec of other
CPUs issue because when those pagevecs will be drained, the mlocked file
pages will go to unevictable LRU. Also this makes the race with munlock
easier to resolve because the pagevec drains happen in LRU lock.However there is still one place which makes a page evictable and does
PageLRU check on that page without LRU lock and needs special attention.
TestClearPageMlocked() and isolate_lru_page() in clear_page_mlock().#0: __pagevec_lru_add_fn #1: clear_page_mlock
SetPageLRU() if (!TestClearPageMlocked())
return
smp_mb() //
Acked-by: Vlastimil Babka
Cc: Jérôme Glisse
Cc: Huang Ying
Cc: Tim Chen
Cc: Michal Hocko
Cc: Greg Thelen
Cc: Johannes Weiner
Cc: Balbir Singh
Cc: Minchan Kim
Cc: Shaohua Li
Cc: Jan Kara
Cc: Nicholas Piggin
Cc: Dan Williams
Cc: Mel Gorman
Cc: Hugh Dickins
Cc: Vlastimil Babka
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
07 Feb, 2018
1 commit
-
so that kernel-doc will properly recognize the parameter and function
descriptions.Link: http://lkml.kernel.org/r/1516700871-22279-2-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport
Cc: Jonathan Corbet
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
29 Nov, 2017
1 commit
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Now that cond_resched() also provides RCU quiescent states when
needed, it can be used in place of cond_resched_rcu_qs(). This
commit therefore makes this change.Signed-off-by: Paul E. McKenney
Cc: Andrew Morton
Cc: "Kirill A. Shutemov"
Cc: Vlastimil Babka
16 Nov, 2017
2 commits
-
lru_add_drain_all() is not required by mlock() and it will drain
everything that has been cached at the time mlock is called. And that
is not really related to the memory which will be faulted in (and
cached) and mlocked by the syscall itself.If anything lru_add_drain_all() should be called _after_ pages have been
mlocked and faulted in but even that is not strictly needed because
those pages would get to the appropriate LRUs lazily during the reclaim
path. Moreover follow_page_pte (gup) will drain the local pcp LRU
cache.On larger machines the overhead of lru_add_drain_all() in mlock() can be
significant when mlocking data already in memory. We have observed high
latency in mlock() due to lru_add_drain_all() when the users were
mlocking in memory tmpfs files.[mhocko@suse.com: changelog fix]
Link: http://lkml.kernel.org/r/20171019222507.2894-1-shakeelb@google.com
Signed-off-by: Shakeel Butt
Acked-by: Michal Hocko
Acked-by: Balbir Singh
Acked-by: Vlastimil Babka
Cc: "Kirill A. Shutemov"
Cc: Joonsoo Kim
Cc: Minchan Kim
Cc: Yisheng Xie
Cc: Ingo Molnar
Cc: Greg Thelen
Cc: Hugh Dickins
Cc: Anshuman Khandual
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Every pagevec_init user claims the pages being released are hot even in
cases where it is unlikely the pages are hot. As no one cares about the
hotness of pages being released to the allocator, just ditch the
parameter.No performance impact is expected as the overhead is marginal. The
parameter is removed simply because it is a bit stupid to have a useless
parameter copied everywhere.Link: http://lkml.kernel.org/r/20171018075952.10627-6-mgorman@techsingularity.net
Signed-off-by: Mel Gorman
Acked-by: Vlastimil Babka
Cc: Andi Kleen
Cc: Dave Chinner
Cc: Dave Hansen
Cc: Jan Kara
Cc: Johannes Weiner
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
02 Nov, 2017
1 commit
-
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.By default all files without license information are under the default
license of the kernel, which is GPL version 2.Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if
Reviewed-by: Philippe Ombredanne
Reviewed-by: Thomas Gleixner
Signed-off-by: Greg Kroah-Hartman
09 Sep, 2017
1 commit
-
page_zone_id() is a specialized function to compare the zone for the pages
that are within the section range. If the section of the pages are
different, page_zone_id() can be different even if their zone is the same.
This wrong usage doesn't cause any actual problem since
__munlock_pagevec_fill() would be called again with failed index.
However, it's better to use more appropriate function here.Link: http://lkml.kernel.org/r/1503559211-10259-1-git-send-email-iamjoonsoo.kim@lge.com
Signed-off-by: Joonsoo Kim
Acked-by: Vlastimil Babka
Cc: Minchan Kim
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
03 Jun, 2017
1 commit
-
Kefeng reported that when running the follow test, the mlock count in
meminfo will increase permanently:[1] testcase
linux:~ # cat test_mlockal
grep Mlocked /proc/meminfo
for j in `seq 0 10`
do
for i in `seq 4 15`
do
./p_mlockall >> log &
done
sleep 0.2
done
# wait some time to let mlock counter decrease and 5s may not enough
sleep 5
grep Mlocked /proc/meminfolinux:~ # cat p_mlockall.c
#include
#include
#include#define SPACE_LEN 4096
int main(int argc, char ** argv)
{
int ret;
void *adr = malloc(SPACE_LEN);
if (!adr)
return -1;ret = mlockall(MCL_CURRENT | MCL_FUTURE);
printf("mlcokall ret = %d\n", ret);ret = munlockall();
printf("munlcokall ret = %d\n", ret);free(adr);
return 0;
}In __munlock_pagevec() we should decrement NR_MLOCK for each page where
we clear the PageMlocked flag. Commit 1ebb7cc6a583 ("mm: munlock: batch
NR_MLOCK zone state updates") has introduced a bug where we don't
decrement NR_MLOCK for pages where we clear the flag, but fail to
isolate them from the lru list (e.g. when the pages are on some other
cpu's percpu pagevec). Since PageMlocked stays cleared, the NR_MLOCK
accounting gets permanently disrupted by this.Fix it by counting the number of page whose PageMlock flag is cleared.
Fixes: 1ebb7cc6a583 (" mm: munlock: batch NR_MLOCK zone state updates")
Link: http://lkml.kernel.org/r/1495678405-54569-1-git-send-email-xieyisheng1@huawei.com
Signed-off-by: Yisheng Xie
Reported-by: Kefeng Wang
Tested-by: Kefeng Wang
Cc: Vlastimil Babka
Cc: Joern Engel
Cc: Mel Gorman
Cc: Michel Lespinasse
Cc: Hugh Dickins
Cc: Rik van Riel
Cc: Johannes Weiner
Cc: Michal Hocko
Cc: Xishi Qiu
Cc: zhongjiang
Cc: Hanjun Guo
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
04 May, 2017
1 commit
-
try_to_munlock returns SWAP_MLOCK if the one of VMAs mapped the page has
VM_LOCKED flag. In that time, VM set PG_mlocked to the page if the page
is not pte-mapped THP which cannot be mlocked, either.With that, __munlock_isolated_page can use PageMlocked to check whether
try_to_munlock is successful or not without relying on try_to_munlock's
retval. It helps to make try_to_unmap/try_to_unmap_one simple with
upcoming patches.[minchan@kernel.org: remove PG_Mlocked VM_BUG_ON check]
Link: http://lkml.kernel.org/r/20170411025615.GA6545@bbox
Link: http://lkml.kernel.org/r/1489555493-14659-5-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim
Acked-by: Kirill A. Shutemov
Acked-by: Vlastimil Babka
Cc: Anshuman Khandual
Cc: Hillf Danton
Cc: Johannes Weiner
Cc: Michal Hocko
Cc: Naoya Horiguchi
Cc: Sasha Levin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
11 Mar, 2017
1 commit
-
Merge 5-level page table prep from Kirill Shutemov:
"Here's relatively low-risk part of 5-level paging patchset. Merging it
now will make x86 5-level paging enabling in v4.12 easier.The first patch is actually x86-specific: detect 5-level paging
support. It boils down to single define.The rest of patchset converts Linux MMU abstraction from 4- to 5-level
paging.Enabling of new abstraction in most cases requires adding single line
of code in arch-specific code. The rest is taken care by asm-generic/.Changes to mm/ code are mostly mechanical: add support for new page
table level -- p4d_t -- where we deal with pud_t now.v2:
- fix build on microblaze (Michal);
- comment for __ARCH_HAS_5LEVEL_HACK in kasan_populate_zero_shadow();
- acks from Michal"* emailed patches from Kirill A Shutemov :
mm: introduce __p4d_alloc()
mm: convert generic code to 5-level paging
asm-generic: introduce
arch, mm: convert all architectures to use 5level-fixup.h
asm-generic: introduce __ARCH_USE_5LEVEL_HACK
asm-generic: introduce 5level-fixup.h
x86/cpufeature: Add 5-level paging detection
10 Mar, 2017
2 commits
-
The following test case triggers BUG() in munlock_vma_pages_range():
int main(int argc, char *argv[])
{
int fd;system("mount -t tmpfs -o huge=always none /mnt");
fd = open("/mnt/test", O_CREAT | O_RDWR);
ftruncate(fd, 4UL << 20);
mmap(NULL, 4UL << 20, PROT_READ | PROT_WRITE,
MAP_SHARED | MAP_FIXED | MAP_LOCKED, fd, 0);
mmap(NULL, 4096, PROT_READ | PROT_WRITE,
MAP_SHARED | MAP_LOCKED, fd, 0);
munlockall();
return 0;
}The second mmap() create PTE-mapping of the first huge page in file. It
makes kernel munlock the page as we never keep PTE-mapped page mlocked.On munlockall() when we handle vma created by the first mmap(),
munlock_vma_page() returns page_mask == 0, as the page is not mlocked
anymore. On next iteration follow_page_mask() return tail page, but
page_mask is HPAGE_NR_PAGES - 1. It makes us skip to the first tail
page of the next huge page and step on
VM_BUG_ON_PAGE(PageMlocked(page)).The fix is not use the page_mask from follow_page_mask() at all. It has
no use for us.Link: http://lkml.kernel.org/r/20170302150252.34120-1-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov
Cc: Andrea Arcangeli
Cc: [4.5+]
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Convert all non-architecture-specific code to 5-level paging.
It's mostly mechanical adding handling one more page table level in
places where we deal with pud_t.Signed-off-by: Kirill A. Shutemov
Acked-by: Michal Hocko
Signed-off-by: Linus Torvalds
02 Mar, 2017
1 commit
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We are going to split out of , which
will have to be picked up from other headers and a couple of .c files.Create a trivial placeholder file that just
maps to to make this patch obviously correct and
bisectable.Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds
Cc: Mike Galbraith
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar
01 Dec, 2016
1 commit
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The following program triggers BUG() in munlock_vma_pages_range():
// autogenerated by syzkaller (http://github.com/google/syzkaller)
#includeint main()
{
mmap((void*)0x20105000ul, 0xc00000ul, 0x2ul, 0x2172ul, -1, 0);
mremap((void*)0x201fd000ul, 0x4000ul, 0xc00000ul, 0x3ul, 0x203f0000ul);
return 0;
}The test-case constructs the situation when munlock_vma_pages_range()
finds PTE-mapped THP-head in the middle of page table and, by mistake,
skips HPAGE_PMD_NR pages after that.As result, on the next iteration it hits the middle of PMD-mapped THP
and gets upset seeing mlocked tail page.The solution is only skip HPAGE_PMD_NR pages if the THP was mlocked
during munlock_vma_page(). It would guarantee that the page is
PMD-mapped as we never mlock PTE-mapeed THPs.Fixes: e90309c9f772 ("thp: allow mlocked THP again")
Link: http://lkml.kernel.org/r/20161115132703.7s7rrgmwttegcdh4@black.fi.intel.com
Signed-off-by: Kirill A. Shutemov
Reported-by: Dmitry Vyukov
Cc: Konstantin Khlebnikov
Cc: Andrey Ryabinin
Cc: syzkaller
Cc: Andrea Arcangeli
Cc: [4.5+]
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
08 Oct, 2016
2 commits
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When one vma was with flag VM_LOCKED|VM_LOCKONFAULT (by invoking
mlock2(,MLOCK_ONFAULT)), it can again be populated with mlock() with
VM_LOCKED flag only.There is a hole in mlock_fixup() which increase mm->locked_vm twice even
the two operations are on the same vma and both with VM_LOCKED flags.The issue can be reproduced by following code:
mlock2(p, 1024 * 64, MLOCK_ONFAULT); //VM_LOCKED|VM_LOCKONFAULT
mlock(p, 1024 * 64); //VM_LOCKEDThen check the increase VmLck field in /proc/pid/status(to 128k).
When vma is set with different vm_flags, and the new vm_flags is with
VM_LOCKED, it is not necessarily be a "new locked" vma. This patch
corrects this bug by prevent mm->locked_vm from increment when old
vm_flags is already VM_LOCKED.Link: http://lkml.kernel.org/r/1472554781-9835-3-git-send-email-wei.guo.simon@gmail.com
Signed-off-by: Simon Guo
Acked-by: Kirill A. Shutemov
Cc: Alexey Klimov
Cc: Eric B Munson
Cc: Geert Uytterhoeven
Cc: Mel Gorman
Cc: Michal Hocko
Cc: Shuah Khan
Cc: Simon Guo
Cc: Thierry Reding
Cc: Vlastimil Babka
Cc: David Rientjes
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
In do_mlock(), the check against locked memory limitation has a hole
which will fail following cases at step 3):1) User has a memory chunk from addressA with 50k, and user mem lock
rlimit is 64k.
2) mlock(addressA, 30k)
3) mlock(addressA, 40k)The 3rd step should have been allowed since the 40k request is
intersected with the previous 30k at step 2), and the 3rd step is
actually for mlock on the extra 10k memory.This patch checks vma to caculate the actual "new" mlock size, if
necessary, and ajust the logic to fix this issue.[akpm@linux-foundation.org: clean up comment layout]
[wei.guo.simon@gmail.com: correct a typo in count_mm_mlocked_page_nr()]
Link: http://lkml.kernel.org/r/1473325970-11393-2-git-send-email-wei.guo.simon@gmail.com
Link: http://lkml.kernel.org/r/1472554781-9835-2-git-send-email-wei.guo.simon@gmail.com
Signed-off-by: Simon Guo
Cc: Alexey Klimov
Cc: Eric B Munson
Cc: Geert Uytterhoeven
Cc: "Kirill A. Shutemov"
Cc: Mel Gorman
Cc: Michal Hocko
Cc: Shuah Khan
Cc: Simon Guo
Cc: Thierry Reding
Cc: Vlastimil Babka
Cc: David Rientjes
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
29 Jul, 2016
2 commits
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This moves the LRU lists from the zone to the node and related data such
as counters, tracing, congestion tracking and writeback tracking.Unfortunately, due to reclaim and compaction retry logic, it is
necessary to account for the number of LRU pages on both zone and node
logic. Most reclaim logic is based on the node counters but the retry
logic uses the zone counters which do not distinguish inactive and
active sizes. It would be possible to leave the LRU counters on a
per-zone basis but it's a heavier calculation across multiple cache
lines that is much more frequent than the retry checks.Other than the LRU counters, this is mostly a mechanical patch but note
that it introduces a number of anomalies. For example, the scans are
per-zone but using per-node counters. We also mark a node as congested
when a zone is congested. This causes weird problems that are fixed
later but is easier to review.In the event that there is excessive overhead on 32-bit systems due to
the nodes being on LRU then there are two potential solutions1. Long-term isolation of highmem pages when reclaim is lowmem
When pages are skipped, they are immediately added back onto the LRU
list. If lowmem reclaim persisted for long periods of time, the same
highmem pages get continually scanned. The idea would be that lowmem
keeps those pages on a separate list until a reclaim for highmem pages
arrives that splices the highmem pages back onto the LRU. It potentially
could be implemented similar to the UNEVICTABLE list.That would reduce the skip rate with the potential corner case is that
highmem pages have to be scanned and reclaimed to free lowmem slab pages.2. Linear scan lowmem pages if the initial LRU shrink fails
This will break LRU ordering but may be preferable and faster during
memory pressure than skipping LRU pages.Link: http://lkml.kernel.org/r/1467970510-21195-4-git-send-email-mgorman@techsingularity.net
Signed-off-by: Mel Gorman
Acked-by: Johannes Weiner
Acked-by: Vlastimil Babka
Cc: Hillf Danton
Cc: Joonsoo Kim
Cc: Michal Hocko
Cc: Minchan Kim
Cc: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Node-based reclaim requires node-based LRUs and locking. This is a
preparation patch that just moves the lru_lock to the node so later
patches are easier to review. It is a mechanical change but note this
patch makes contention worse because the LRU lock is hotter and direct
reclaim and kswapd can contend on the same lock even when reclaiming
from different zones.Link: http://lkml.kernel.org/r/1467970510-21195-3-git-send-email-mgorman@techsingularity.net
Signed-off-by: Mel Gorman
Reviewed-by: Minchan Kim
Acked-by: Johannes Weiner
Acked-by: Vlastimil Babka
Cc: Hillf Danton
Cc: Joonsoo Kim
Cc: Michal Hocko
Cc: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
24 May, 2016
1 commit
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This is a follow up work for oom_reaper [1]. As the async OOM killing
depends on oom_sem for read we would really appreciate if a holder for
write didn't stood in the way. This patchset is changing many of
down_write calls to be killable to help those cases when the writer is
blocked and waiting for readers to release the lock and so help
__oom_reap_task to process the oom victim.Most of the patches are really trivial because the lock is help from a
shallow syscall paths where we can return EINTR trivially and allow the
current task to die (note that EINTR will never get to the userspace as
the task has fatal signal pending). Others seem to be easy as well as
the callers are already handling fatal errors and bail and return to
userspace which should be sufficient to handle the failure gracefully.
I am not familiar with all those code paths so a deeper review is really
appreciated.As this work is touching more areas which are not directly connected I
have tried to keep the CC list as small as possible and people who I
believed would be familiar are CCed only to the specific patches (all
should have received the cover though).This patchset is based on linux-next and it depends on
down_write_killable for rw_semaphores which got merged into tip
locking/rwsem branch and it is merged into this next tree. I guess it
would be easiest to route these patches via mmotm because of the
dependency on the tip tree but if respective maintainers prefer other
way I have no objections.I haven't covered all the mmap_write(mm->mmap_sem) instances here
$ git grep "down_write(.*\)" next/master | wc -l
98
$ git grep "down_write(.*\)" | wc -l
62I have tried to cover those which should be relatively easy to review in
this series because this alone should be a nice improvement. Other
places can be changed on top.[0] http://lkml.kernel.org/r/1456752417-9626-1-git-send-email-mhocko@kernel.org
[1] http://lkml.kernel.org/r/1452094975-551-1-git-send-email-mhocko@kernel.org
[2] http://lkml.kernel.org/r/1456750705-7141-1-git-send-email-mhocko@kernel.orgThis patch (of 18):
This is the first step in making mmap_sem write waiters killable. It
focuses on the trivial ones which are taking the lock early after
entering the syscall and they are not changing state before.Therefore it is very easy to change them to use down_write_killable and
immediately return with -EINTR. This will allow the waiter to pass away
without blocking the mmap_sem which might be required to make a forward
progress. E.g. the oom reaper will need the lock for reading to
dismantle the OOM victim address space.The only tricky function in this patch is vm_mmap_pgoff which has many
call sites via vm_mmap. To reduce the risk keep vm_mmap with the
original non-killable semantic for now.vm_munmap callers do not bother checking the return value so open code
it into the munmap syscall path for now for simplicity.Signed-off-by: Michal Hocko
Acked-by: Vlastimil Babka
Cc: Mel Gorman
Cc: "Kirill A. Shutemov"
Cc: Konstantin Khlebnikov
Cc: Hugh Dickins
Cc: Andrea Arcangeli
Cc: David Rientjes
Cc: Dave Hansen
Cc: Johannes Weiner
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
22 Jan, 2016
1 commit
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Tetsuo Handa reported underflow of NR_MLOCK on munlock.
Testcase:
#include
#include
#include#define BASE ((void *)0x400000000000)
#define SIZE (1UL << 21)int main(int argc, char *argv[])
{
void *addr;system("grep Mlocked /proc/meminfo");
addr = mmap(BASE, SIZE, PROT_READ | PROT_WRITE,
MAP_ANONYMOUS | MAP_PRIVATE | MAP_LOCKED | MAP_FIXED,
-1, 0);
if (addr == MAP_FAILED)
printf("mmap() failed\n"), exit(1);
munmap(addr, SIZE);
system("grep Mlocked /proc/meminfo");
return 0;
}It happens on munlock_vma_page() due to unfortunate choice of nr_pages
data type:__mod_zone_page_state(zone, NR_MLOCK, -nr_pages);
For unsigned int nr_pages, implicitly casted to long in
__mod_zone_page_state(), it becomes something around UINT_MAX.munlock_vma_page() usually called for THP as small pages go though
pagevec.Let's make nr_pages signed int.
Similar fixes in 6cdb18ad98a4 ("mm/vmstat: fix overflow in
mod_zone_page_state()") used `long' type, but `int' here is OK for a
count of the number of sub-pages in a huge page.Fixes: ff6a6da60b89 ("mm: accelerate munlock() treatment of THP pages")
Signed-off-by: Kirill A. Shutemov
Reported-by: Tetsuo Handa
Tested-by: Tetsuo Handa
Cc: Michel Lespinasse
Acked-by: Michal Hocko
Cc: [4.4+]
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
16 Jan, 2016
3 commits
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Since can_do_mlock only return 1 or 0, so make it boolean.
No functional change.
[akpm@linux-foundation.org: update declaration in mm.h]
Signed-off-by: Wang Xiaoqiang
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Before THP refcounting rework, THP was not allowed to cross VMA
boundary. So, if we have THP and we split it, PG_mlocked can be safely
transferred to small pages.With new THP refcounting and naive approach to mlocking we can end up
with this scenario:
1. we have a mlocked THP, which belong to one VM_LOCKED VMA.
2. the process does munlock() on the *part* of the THP:
- the VMA is split into two, one of them VM_LOCKED;
- huge PMD split into PTE table;
- THP is still mlocked;
3. split_huge_page():
- it transfers PG_mlocked to *all* small pages regrardless if it
blong to any VM_LOCKED VMA.We probably could munlock() all small pages on split_huge_page(), but I
think we have accounting issue already on step two.Instead of forbidding mlocked pages altogether, we just avoid mlocking
PTE-mapped THPs and munlock THPs on split_huge_pmd().This means PTE-mapped THPs will be on normal lru lists and will be split
under memory pressure by vmscan. After the split vmscan will detect
unevictable small pages and mlock them.With this approach we shouldn't hit situation like described above.
Signed-off-by: Kirill A. Shutemov
Cc: Sasha Levin
Cc: Aneesh Kumar K.V
Cc: Jerome Marchand
Cc: Vlastimil Babka
Cc: Andrea Arcangeli
Cc: Hugh Dickins
Cc: Dave Hansen
Cc: Mel Gorman
Cc: Rik van Riel
Cc: Naoya Horiguchi
Cc: Steve Capper
Cc: Johannes Weiner
Cc: Michal Hocko
Cc: Christoph Lameter
Cc: David Rientjes
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
With new refcounting THP can belong to several VMAs. This makes tricky
to track THP pages, when they partially mlocked. It can lead to leaking
mlocked pages to non-VM_LOCKED vmas and other problems.With this patch we will split all pages on mlock and avoid
fault-in/collapse new THP in VM_LOCKED vmas.I've tried alternative approach: do not mark THP pages mlocked and keep
them on normal LRUs. This way vmscan could try to split huge pages on
memory pressure and free up subpages which doesn't belong to VM_LOCKED
vmas. But this is user-visible change: we screw up Mlocked accouting
reported in meminfo, so I had to leave this approach aside.We can bring something better later, but this should be good enough for
now.Signed-off-by: Kirill A. Shutemov
Tested-by: Sasha Levin
Tested-by: Aneesh Kumar K.V
Acked-by: Jerome Marchand
Cc: Vlastimil Babka
Cc: Andrea Arcangeli
Cc: Hugh Dickins
Cc: Dave Hansen
Cc: Mel Gorman
Cc: Rik van Riel
Cc: Naoya Horiguchi
Cc: Steve Capper
Cc: Johannes Weiner
Cc: Michal Hocko
Cc: Christoph Lameter
Cc: David Rientjes
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
15 Jan, 2016
1 commit
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Before usage page pointer initialized by NULL is reinitialized by
follow_page_mask(). Drop useless init of page pointer in the beginning
of loop.Signed-off-by: Alexey Klimov
Acked-by: Vlastimil Babka
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
