Commit graph

659450 commits

Author SHA1 Message Date
zhong jiang
d6d8c8a482 mm/memory_hotplug.c: fix overflow in test_pages_in_a_zone()
When mainline introduced commit a96dfddbcc ("base/memory, hotplug: fix
a kernel oops in show_valid_zones()"), it obtained the valid start and
end pfn from the given pfn range.  The valid start pfn can fix the
actual issue, but it introduced another issue.  The valid end pfn will
may exceed the given end_pfn.

Although the incorrect overflow will not result in actual problem at
present, but I think it need to be fixed.

[toshi.kani@hpe.com: remove assumption that end_pfn is aligned by MAX_ORDER_NR_PAGES]
Fixes: a96dfddbcc ("base/memory, hotplug: fix a kernel oops in show_valid_zones()")
Link: http://lkml.kernel.org/r/1486467299-22648-1-git-send-email-zhongjiang@huawei.com
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:56 -08:00
zhouxianrong
8e19d540d1 zram: extend zero pages to same element pages
The idea is that without doing more calculations we extend zero pages to
same element pages for zram.  zero page is special case of same element
page with zero element.

1. the test is done under android 7.0
2. startup too many applications circularly
3. sample the zero pages, same pages (none-zero element)
   and total pages in function page_zero_filled

the result is listed as below:

ZERO	SAME	TOTAL
36214	17842	598196

		ZERO/TOTAL	 SAME/TOTAL	  (ZERO+SAME)/TOTAL ZERO/SAME
AVERAGE	0.060631909	 0.024990816  0.085622726		2.663825038
STDEV	0.00674612	 0.005887625  0.009707034		2.115881328
MAX		0.069698422	 0.030046087  0.094975336		7.56043956
MIN		0.03959586	 0.007332205  0.056055193		1.928985507

from the above data, the benefit is about 2.5% and up to 3% of total
swapout pages.

The defect of the patch is that when we recovery a page from non-zero
element the operations are low efficient for partial read.

This patch extends zero_page to same_page so if there is any user to
have monitored zero_pages, he will be surprised if the number is
increased but it's not harmful, I believe.

[minchan@kernel.org: do not free same element pages in zram_meta_free]
  Link: http://lkml.kernel.org/r/20170207065741.GA2567@bbox
Link: http://lkml.kernel.org/r/1483692145-75357-1-git-send-email-zhouxianrong@huawei.com
Link: http://lkml.kernel.org/r/1486307804-27903-1-git-send-email-minchan@kernel.org
Signed-off-by: zhouxianrong <zhouxianrong@huawei.com>
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:56 -08:00
Steven Rostedt (VMware)
517663edd6 mm/page-writeback.c: place "not" inside of unlikely() statement in wb_domain_writeout_inc()
The likely/unlikely profiler noticed that the unlikely statement in
wb_domain_writeout_inc() is constantly wrong.  This is due to the "not"
(!) being outside the unlikely statement.  It is likely that
dom->period_time will be set, but unlikely that it wont be.  Move the
not into the unlikely statement.

Link: http://lkml.kernel.org/r/20170206120035.3c2e2b91@gandalf.local.home
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:56 -08:00
Aneesh Kumar K.V
c137a2757b powerpc/mm/autonuma: switch ppc64 to its own implementation of saved write
With this our protnone becomes a present pte with READ/WRITE/EXEC bit
cleared.  By default we also set _PAGE_PRIVILEGED on such pte.  This is
now used to help us identify a protnone pte that as saved write bit.
For such pte, we will clear the _PAGE_PRIVILEGED bit.  The pte still
remain non-accessible from both user and kernel.

[aneesh.kumar@linux.vnet.ibm.com: v3]
  Link: http://lkml.kernel.org/r/1487498625-10891-4-git-send-email-aneesh.kumar@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1487050314-3892-3-git-send-email-aneesh.kumar@linux.vnet.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Michael Neuling <mikey@neuling.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michael Ellerman <michaele@au1.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:56 -08:00
Aneesh Kumar K.V
595cd8f256 mm/ksm: handle protnone saved writes when making page write protect
Without this KSM will consider the page write protected, but a numa
fault can later mark the page writable.  This can result in memory
corruption.

Link: http://lkml.kernel.org/r/1487498625-10891-3-git-send-email-aneesh.kumar@linux.vnet.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:56 -08:00
Aneesh Kumar K.V
288bc54949 mm/autonuma: let architecture override how the write bit should be stashed in a protnone pte.
Patch series "Numabalancing preserve write fix", v2.

This patch series address an issue w.r.t THP migration and autonuma
preserve write feature.  migrate_misplaced_transhuge_page() cannot deal
with concurrent modification of the page.  It does a page copy without
following the migration pte sequence.  IIUC, this was done to keep the
migration simpler and at the time of implemenation we didn't had THP
page cache which would have required a more elaborate migration scheme.
That means thp autonuma migration expect the protnone with saved write
to be done such that both kernel and user cannot update the page
content.  This patch series enables archs like ppc64 to do that.  We are
good with the hash translation mode with the current code, because we
never create a hardware page table entry for a protnone pte.

This patch (of 2):

Autonuma preserves the write permission across numa fault to avoid
taking a writefault after a numa fault (Commit: b191f9b106 " mm: numa:
preserve PTE write permissions across a NUMA hinting fault").
Architecture can implement protnone in different ways and some may
choose to implement that by clearing Read/ Write/Exec bit of pte.
Setting the write bit on such pte can result in wrong behaviour.  Fix
this up by allowing arch to override how to save the write bit on a
protnone pte.

[aneesh.kumar@linux.vnet.ibm.com: don't mark pte saved write in case of dirty_accountable]
  Link: http://lkml.kernel.org/r/1487942884-16517-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com
[aneesh.kumar@linux.vnet.ibm.com: v3]
  Link: http://lkml.kernel.org/r/1487498625-10891-2-git-send-email-aneesh.kumar@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1487050314-3892-2-git-send-email-aneesh.kumar@linux.vnet.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Michael Neuling <mikey@neuling.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michael Ellerman <michaele@au1.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:56 -08:00
Aneesh Kumar K.V
cee216a696 mm/autonuma: don't use set_pte_at when updating protnone ptes
Architectures like ppc64, use privilege access bit to mark pte non
accessible.  This implies that kernel can do a copy_to_user to an
address marked for numa fault.  This also implies that there can be a
parallel hardware update for the pte.  set_pte_at cannot be used in such
scenarios.  Hence switch the pte update to use ptep_get_and_clear and
set_pte_at combination.

[akpm@linux-foundation.org: remove unwanted ppc change, per Aneesh]
Link: http://lkml.kernel.org/r/1486400776-28114-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:56 -08:00
Steven Rostedt (VMware)
3f472cc978 mm/shmem.c: fix unlikely() test of info->seals to test only for WRITE and GROW
Running my likely/unlikely profiler, I discovered that the test in
shmem_write_begin() that tests for info->seals as unlikely, is always
incorrect.  This is because shmem_get_inode() sets info->seals to have
F_SEAL_SEAL set by default, and it is unlikely to be cleared when
shmem_write_begin() is called.  Thus, the if statement is very likely.

But as the if statement block only cares about F_SEAL_WRITE and
F_SEAL_GROW, change the test to only test those two bits.

Link: http://lkml.kernel.org/r/20170203105656.7aec6237@gandalf.local.home
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:56 -08:00
Mel Gorman
c2f83143f1 mm, vmscan: clear PGDAT_WRITEBACK when zone is balanced
Hillf Danton pointed out that since commit 1d82de618d ("mm, vmscan:
make kswapd reclaim in terms of nodes") that PGDAT_WRITEBACK is no
longer cleared.

It was not noticed as triggering it requires pages under writeback to
cycle twice through the LRU and before kswapd gets stalled.
Historically, such issues tended to occur on small machines writing
heavily to slow storage such as a USB stick.

Once kswapd stalls, direct reclaim stalls may be higher but due to the
fact that memory pressure is required, it would not be very noticable.

Michal Hocko suggested removing the flag entirely but the conservative
fix is to restore the intended PGDAT_WRITEBACK behaviour and clear the
flag when a suitable zone is balanced.

Fixes: 1d82de618d ("mm, vmscan: make kswapd reclaim in terms of nodes")
Link: http://lkml.kernel.org/r/20170203203222.gq7hk66yc36lpgtb@suse.de
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Ross Zwisler
8f526e1242 drm: remove unnecessary fault wrappers
The fault wrappers drm_vm_fault(), drm_vm_shm_fault(),
drm_vm_dma_fault() and drm_vm_sg_fault() used to provide extra logic
beyond what was in the "drm_do_*" versions of these functions, but as of
commit ca0b07d9a9 ("drm: convert drm from nopage to fault") they are
just unnecessary wrappers that do nothing.

Remove them, and rename the the drm_do_* fault handlers to remove the
"do_" since they no longer have corresponding wrappers.

Link: http://lkml.kernel.org/r/1486155698-25717-1-git-send-email-ross.zwisler@linux.intel.com
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Tobin C Harding
166f61b943 mm: codgin-style fixes
Fix whitespace issues, extraneous braces.

Link: http://lkml.kernel.org/r/1485992240-10986-5-git-send-email-me@tobin.cc
Signed-off-by: Tobin C Harding <me@tobin.cc>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Tobin C Harding
7f2b6ce8e3 mm/memory.c: use NULL instead of literal 0
Patch fixes sparse warning: Using plain integer as NULL pointer.
Replaces assignment of 0 to pointer with NULL assignment.

Link: http://lkml.kernel.org/r/1485992240-10986-2-git-send-email-me@tobin.cc
Signed-off-by: Tobin C Harding <me@tobin.cc>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Masanari Iida
f2bf14d14d mm/page_alloc.c: remove duplicate inclusion of page_ext.h
Link: http://lkml.kernel.org/r/20170202011942.1609-1-standby24x7@gmail.com
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Michal Hocko
5d17a73a2e vmalloc: back off when the current task is killed
__vmalloc_area_node() allocates pages to cover the requested vmalloc
size.  This can be a lot of memory.  If the current task is killed by
the OOM killer, and thus has an unlimited access to memory reserves, it
can consume all the memory theoretically.  Fix this by checking for
fatal_signal_pending and back off early.

Link: http://lkml.kernel.org/r/20170201092706.9966-4-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Jaewon Kim
dbe43d4d28 mm: cma: print allocation failure reason and bitmap status
There are many reasons of CMA allocation failure such as EBUSY, ENOMEM,
EINTR.  But we did not know error reason so far.  This patch prints the
error value.

Additionally if CONFIG_CMA_DEBUG is enabled, this patch shows bitmap
status to know available pages.  Actually CMA internally tries on all
available regions because some regions can be failed because of EBUSY.
Bitmap status is useful to know in detail on both ENONEM and EBUSY;

 ENOMEM: not tried at all because of no available region
         it could be too small total region or could be fragmentation issue
 EBUSY:  tried some region but all failed

This is an ENOMEM example with this patch.

    [2:   Binder:714_1:  744] cma: cma_alloc: alloc failed, req-size: 256 pages, ret: -12

If CONFIG_CMA_DEBUG is enabled, avabile pages also will be shown as
concatenated size@position format.  So 4@572 means that there are 4
available pages at 572 position starting from 0 position.

    [2:   Binder:714_1:  744] cma: number of available pages: 4@572+7@585+7@601+8@632+38@730+166@1114+127@1921=> 357 free of 2048 total pages

Link: http://lkml.kernel.org/r/1485909785-3952-1-git-send-email-jaewon31.kim@samsung.com
Signed-off-by: Jaewon Kim <jaewon31.kim@samsung.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
David Rientjes
def5efe037 mm, madvise: fail with ENOMEM when splitting vma will hit max_map_count
If madvise(2) advice will result in the underlying vma being split and
the number of areas mapped by the process will exceed
/proc/sys/vm/max_map_count as a result, return ENOMEM instead of EAGAIN.

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

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

Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1701241431120.42507@chino.kir.corp.google.com
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Lucas Stach
712c604dcd mm: wire up GFP flag passing in dma_alloc_from_contiguous
The callers of the DMA alloc functions already provide the proper
context GFP flags.  Make sure to pass them through to the CMA allocator,
to make the CMA compaction context aware.

Link: http://lkml.kernel.org/r/20170127172328.18574-3-l.stach@pengutronix.de
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Alexander Graf <agraf@suse.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Lucas Stach
e2f466e32f mm: cma_alloc: allow to specify GFP mask
Most users of this interface just want to use it with the default
GFP_KERNEL flags, but for cases where DMA memory is allocated it may be
called from a different context.

No functional change yet, just passing through the flag to the
underlying alloc_contig_range function.

Link: http://lkml.kernel.org/r/20170127172328.18574-2-l.stach@pengutronix.de
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Alexander Graf <agraf@suse.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Lucas Stach
ca96b62534 mm: alloc_contig_range: allow to specify GFP mask
Currently alloc_contig_range assumes that the compaction should be done
with the default GFP_KERNEL flags.  This is probably right for all
current uses of this interface, but may change as CMA is used in more
use-cases (including being the default DMA memory allocator on some
platforms).

Change the function prototype, to allow for passing through the GFP mask
set by upper layers.

Also respect global restrictions by applying memalloc_noio_flags to the
passed in flags.

Link: http://lkml.kernel.org/r/20170127172328.18574-1-l.stach@pengutronix.de
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Alexander Graf <agraf@suse.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Mike Rapoport
5a02026d39 userfaultfd: documentation update
Add documentation about new userfaultfd features and events

Link: http://lkml.kernel.org/r/1487716431-5551-1-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Mike Rapoport
96333187ab userfaultfd_copy: return -ENOSPC in case mm has gone
In the non-cooperative userfaultfd case, the process exit may race with
outstanding mcopy_atomic called by the uffd monitor.  Returning -ENOSPC
instead of -EINVAL when mm is already gone will allow uffd monitor to
distinguish this case from other error conditions.

Link: http://lkml.kernel.org/r/1485542673-24387-6-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Mike Rapoport
27d02568f5 userfaultfd: mcopy_atomic: return -ENOENT when no compatible VMA found
The memory mapping of a process may change between #PF event and the
call to mcopy_atomic that comes to resolve the page fault.  In such
case, there will be no VMA covering the range passed to mcopy_atomic or
the VMA will not have userfaultfd context.

To allow uffd monitor to distinguish those case from other errors, let's
return -ENOENT instead of -EINVAL.

Note, that despite availability of UFFD_EVENT_UNMAP there still might be
race between the processing of UFFD_EVENT_UNMAP and outstanding
mcopy_atomic in case of non-cooperative uffd usage.

[rppt@linux.vnet.ibm.com: update cases returning -ENOENT]
  Link: http://lkml.kernel.org/r/20170207150249.GA6709@rapoport-lnx
[aarcange@redhat.com: merge fix]
[akpm@linux-foundation.org: fix the merge fix]
Link: http://lkml.kernel.org/r/1485542673-24387-5-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Mike Rapoport
ca49ca7114 userfaultfd: non-cooperative: add event for exit() notification
Allow userfaultfd monitor track termination of the processes that have
memory backed by the uffd.

[rppt@linux.vnet.ibm.com: add comment]
  Link: http://lkml.kernel.org/r/20170202135448.GB19804@rapoport-lnxLink: http://lkml.kernel.org/r/1485542673-24387-4-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Mike Rapoport
897ab3e0c4 userfaultfd: non-cooperative: add event for memory unmaps
When a non-cooperative userfaultfd monitor copies pages in the
background, it may encounter regions that were already unmapped.
Addition of UFFD_EVENT_UNMAP allows the uffd monitor to track precisely
changes in the virtual memory layout.

Since there might be different uffd contexts for the affected VMAs, we
first should create a temporary representation for the unmap event for
each uffd context and then notify them one by one to the appropriate
userfault file descriptors.

The event notification occurs after the mmap_sem has been released.

[arnd@arndb.de: fix nommu build]
  Link: http://lkml.kernel.org/r/20170203165141.3665284-1-arnd@arndb.de
[mhocko@suse.com: fix nommu build]
  Link: http://lkml.kernel.org/r/20170202091503.GA22823@dhcp22.suse.cz
Link: http://lkml.kernel.org/r/1485542673-24387-3-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Mike Rapoport
846b1a0f1d mm: call vm_munmap in munmap syscall instead of using open coded version
Patch series "userfaultfd: non-cooperative: better tracking for mapping
changes", v2.

These patches try to address issues I've encountered during integration
of userfaultfd with CRIU.

Previously added userfaultfd events for fork(), madvise() and mremap()
unfortunately do not cover all possible changes to a process virtual
memory layout required for uffd monitor.

When one or more VMAs is removed from the process mm, the external uffd
monitor has no way to detect those changes and will attempt to fill the
removed regions with userfaultfd_copy.

Another problematic event is the exit() of the process.  Here again, the
external uffd monitor will try to use userfaultfd_copy, although mm
owning the memory has already gone.

The first patch in the series is a minor cleanup and it's not strictly
related to the rest of the series.

The patches 2 and 3 below add UFFD_EVENT_UNMAP and UFFD_EVENT_EXIT to
allow the uffd monitor track changes in the memory layout of a process.

The patches 4 and 5 amend error codes returned by userfaultfd_copy to
make the uffd monitor able to cope with races that might occur between
delivery of unmap and exit events and outstanding userfaultfd_copy's.

This patch (of 5):

Commit dc0ef0df7b ("mm: make mmap_sem for write waits killable for mm
syscalls") replaced call to vm_munmap in munmap syscall with open coded
version to allow different waits on mmap_sem in munmap syscall and
vm_munmap.

Now both functions use down_write_killable, so we can restore the call
to vm_munmap from the munmap system call.

Link: http://lkml.kernel.org/r/1485542673-24387-2-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Kirill A. Shutemov
3fe87967c5 mm: convert remove_migration_pte() to use page_vma_mapped_walk()
remove_migration_pte() also can easily be converted to
page_vma_mapped_walk().

[akpm@linux-foundation.org: coding-style fixes]
Link: http://lkml.kernel.org/r/20170129173858.45174-13-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Kirill A. Shutemov
d53a8b49a6 mm: drop page_check_address{,_transhuge}
All users are gone. Let's drop them.

Link: http://lkml.kernel.org/r/20170129173858.45174-12-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Kirill A. Shutemov
6a328a626f mm: convert page_mapped_in_vma() to use page_vma_mapped_walk()
For consistency, it worth converting all page_check_address() to
page_vma_mapped_walk(), so we could drop the former.

Link: http://lkml.kernel.org/r/20170129173858.45174-11-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Kirill A. Shutemov
14fa2daa15 mm, uprobes: convert __replace_page() to use page_vma_mapped_walk()
For consistency, it worth converting all page_check_address() to
page_vma_mapped_walk(), so we could drop the former.

Link: http://lkml.kernel.org/r/20170129173858.45174-10-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Kirill A. Shutemov
36eaff3364 mm, ksm: convert write_protect_page() to use page_vma_mapped_walk()
For consistency, it worth converting all page_check_address() to
page_vma_mapped_walk(), so we could drop the former.

Link: http://lkml.kernel.org/r/20170129173858.45174-9-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Kirill A. Shutemov
c7ab0d2fdc mm: convert try_to_unmap_one() to use page_vma_mapped_walk()
For consistency, it worth converting all page_check_address() to
page_vma_mapped_walk(), so we could drop the former.

It also makes freeze_page() as we walk though rmap only once.

Link: http://lkml.kernel.org/r/20170129173858.45174-8-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Kirill A. Shutemov
f27176cfc3 mm: convert page_mkclean_one() to use page_vma_mapped_walk()
For consistency, it worth converting all page_check_address() to
page_vma_mapped_walk(), so we could drop the former.

PMD handling here is future-proofing, we don't have users yet.  ext4
with huge pages will be the first.

Link: http://lkml.kernel.org/r/20170129173858.45174-7-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Kirill A. Shutemov
a8fa41ad2f mm, rmap: check all VMAs that PTE-mapped THP can be part of
Current rmap code can miss a VMA that maps PTE-mapped THP if the first
suppage of the THP was unmapped from the VMA.

We need to walk rmap for the whole range of offsets that THP covers, not
only the first one.

vma_address() also need to be corrected to check the range instead of
the first subpage.

Link: http://lkml.kernel.org/r/20170129173858.45174-6-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Kirill A. Shutemov
699fa21680 mm: fix handling PTE-mapped THPs in page_idle_clear_pte_refs()
For PTE-mapped THP page_check_address_transhuge() is not adequate: it
cannot find all relevant PTEs, only the first one.i

Let's switch it to page_vma_mapped_walk().

I don't think it's subject for stable@: it's not fatal.

Link: http://lkml.kernel.org/r/20170129173858.45174-5-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Kirill A. Shutemov
8eaedede82 mm: fix handling PTE-mapped THPs in page_referenced()
For PTE-mapped THP page_check_address_transhuge() is not adequate: it
cannot find all relevant PTEs, only the first one.  It means we can miss
some references of the page and it can result in suboptimal decisions by
vmscan.

Let's switch it to page_vma_mapped_walk().

I don't think it's subject for stable@: it's not fatal.  The only side
effect is that THP can be swapped out when it shouldn't.

Link: http://lkml.kernel.org/r/20170129173858.45174-4-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Kirill A. Shutemov
ace71a19ce mm: introduce page_vma_mapped_walk()
Introduce a new interface to check if a page is mapped into a vma.  It
aims to address shortcomings of page_check_address{,_transhuge}.

Existing interface is not able to handle PTE-mapped THPs: it only finds
the first PTE.  The rest lefted unnoticed.

page_vma_mapped_walk() iterates over all possible mapping of the page in
the vma.

Link: http://lkml.kernel.org/r/20170129173858.45174-3-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Kirill A. Shutemov
c8394812e5 uprobes: split THPs before trying to replace them
Patch series "Fix few rmap-related THP bugs", v3.

The patchset fixes handing PTE-mapped THPs in page_referenced() and
page_idle_clear_pte_refs().

To achieve that I've intrdocued new helper -- page_vma_mapped_walk() --
which replaces all page_check_address{,_transhuge}() and covers all THP
cases.

Patchset overview:
  - First patch fixes one uprobe bug (unrelated to the rest of the
    patchset, just spotted it at the same time);

  - Patches 2-5 fix handling PTE-mapped THPs in page_referenced(),
    page_idle_clear_pte_refs() and rmap core;

  - Patches 6-12 convert all page_check_address{,_transhuge}() users
    (plus remove_migration_pte()) to page_vma_mapped_walk() and drop
    unused helpers.

I think the fixes are not critical enough for stable@ as they don't lead
to crashes or hangs, only suboptimal behaviour.

This patch (of 12):

For THPs page_check_address() always fails.  It leads to endless loop in
uprobe_write_opcode().

Testcase with huge-tmpfs (uprobes cannot probe anonymous memory).

	mount -t debugfs none /sys/kernel/debug
	mount -t tmpfs -o huge=always none /mnt
	gcc -Wall -O2 -o /mnt/test -x c - <<EOF
	int main(void)
	{
		return 0;
	}
	/* Padding to map the code segment with huge pmd */
	asm (".zero 2097152");
	EOF
	echo 'p /mnt/test:0' > /sys/kernel/debug/tracing/uprobe_events
	echo 1 > /sys/kernel/debug/tracing/events/uprobes/enable
	/mnt/test

Let's split THPs before trying to replace.

Link: http://lkml.kernel.org/r/20170129173858.45174-2-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Yisheng Xie
0efadf48bc mm/hotplug: enable memory hotplug for non-lru movable pages
We had considered all of the non-lru pages as unmovable before commit
bda807d444 ("mm: migrate: support non-lru movable page migration").
But now some of non-lru pages like zsmalloc, virtio-balloon pages also
become movable.  So we can offline such blocks by using non-lru page
migration.

This patch straightforwardly adds non-lru migration code, which means
adding non-lru related code to the functions which scan over pfn and
collect pages to be migrated and isolate them before migration.

Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Yisheng Xie <xieyisheng1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Yisheng Xie
85fbe5d1b5 HWPOISON: soft offlining for non-lru movable page
Extend soft offlining framework to support non-lru page, which already
support migration after commit bda807d444 ("mm: migrate: support
non-lru movable page migration")

When memory corrected errors occur on a non-lru movable page, we can
choose to stop using it by migrating data onto another page and disable
the original (maybe half-broken) one.

Link: http://lkml.kernel.org/r/1485867981-16037-4-git-send-email-ysxie@foxmail.com
Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Suggested-by: Michal Hocko <mhocko@kernel.org>
Suggested-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Yisheng Xie
cbae0170e5 mm/migration: make isolate_movable_page always defined
Define isolate_movable_page as a static inline function when
CONFIG_MIGRATION is not enable.  It should return -EBUSY here which
means failed to isolate movable pages.

This patch do not have any functional change but prepare for later
patch.

Link: http://lkml.kernel.org/r/1485867981-16037-3-git-send-email-ysxie@foxmail.com
Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Suggested-by: Michal Hocko <mhocko@kernel.org>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Yisheng Xie
9e5bcd610f mm/migration: make isolate_movable_page() return int type
Patch series "HWPOISON: soft offlining for non-lru movable page", v6.

After Minchan's commit bda807d444 ("mm: migrate: support non-lru
movable page migration"), some type of non-lru page like zsmalloc and
virtio-balloon page also support migration.

Therefore, we can:

1) soft offlining no-lru movable pages, which means when memory
   corrected errors occur on a non-lru movable page, we can stop to use
   it by migrating data onto another page and disable the original
   (maybe half-broken) one.

2) enable memory hotplug for non-lru movable pages, i.e. we may offline
   blocks, which include such pages, by using non-lru page migration.

This patchset is heavily dependent on non-lru movable page migration.

This patch (of 4):

Change the return type of isolate_movable_page() from bool to int.  It
will return 0 when isolate movable page successfully, and return -EBUSY
when it isolates failed.

There is no functional change within this patch but prepare for later
patch.

[xieyisheng1@huawei.com: v6]
  Link: http://lkml.kernel.org/r/1486108770-630-2-git-send-email-xieyisheng1@huawei.com
Link: http://lkml.kernel.org/r/1485867981-16037-2-git-send-email-ysxie@foxmail.com
Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Suggested-by: Michal Hocko <mhocko@kernel.org>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Vitaly Wool
5a27aa8220 z3fold: add kref refcounting
With both coming and already present locking optimizations, introducing
kref to reference-count z3fold objects is the right thing to do.
Moreover, it makes buddied list no longer necessary, and allows for a
simpler handling of headless pages.

[akpm@linux-foundation.org: coding-style fixes]
Link: http://lkml.kernel.org/r/20170131214650.8ea78033d91ded233f552bc0@gmail.com
Signed-off-by: Vitaly Wool <vitalywool@gmail.com>
Reviewed-by: Dan Streetman <ddstreet@ieee.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:54 -08:00
Vitaly Wool
2f1e5e4d84 z3fold: use per-page spinlock
Most of z3fold operations are in-page, such as modifying z3fold page
header or moving z3fold objects within a page.  Taking per-pool spinlock
to protect per-page objects is therefore suboptimal, and the idea of
having a per-page spinlock (or rwlock) has been around for some time.

This patch implements spinlock-based per-page locking mechanism which is
lightweight enough to normally fit ok into the z3fold header.

Link: http://lkml.kernel.org/r/20170131214438.433e0a5fda908337b63206d3@gmail.com
Signed-off-by: Vitaly Wool <vitalywool@gmail.com>
Reviewed-by: Dan Streetman <ddstreet@ieee.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:54 -08:00
Vitaly Wool
1b096e5ae9 z3fold: extend compaction function
z3fold_compact_page() currently only handles the situation when there's
a single middle chunk within the z3fold page.  However it may be worth
it to move middle chunk closer to either first or last chunk, whichever
is there, if the gap between them is big enough.

This patch adds the relevant code, using BIG_CHUNK_GAP define as a
threshold for middle chunk to be worth moving.

Link: http://lkml.kernel.org/r/20170131214334.c4f3eac9a477af0fa9a22c46@gmail.com
Signed-off-by: Vitaly Wool <vitalywool@gmail.com>
Reviewed-by: Dan Streetman <ddstreet@ieee.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:54 -08:00
Vitaly Wool
ede93213aa z3fold: fix header size related issues
Currently the whole kernel build will be stopped if the size of struct
z3fold_header is greater than the size of one chunk, which is 64 bytes
by default.  This patch instead defines the offset for z3fold objects as
the size of the z3fold header in chunks.

Fixed also are the calculation of num_free_chunks() and the address to
move the middle chunk to in case of in-page compaction in
z3fold_compact_page().

Link: http://lkml.kernel.org/r/20170131214057.d98677032bc7b1c6c59a80c9@gmail.com
Signed-off-by: Vitaly Wool <vitalywool@gmail.com>
Reviewed-by: Dan Streetman <ddstreet@ieee.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:54 -08:00
Vitaly Wool
12d59ae678 z3fold: make pages_nr atomic
Convert pages_nr per-pool counter to atomic64_t.

Link: http://lkml.kernel.org/r/20170131213946.b828676ab17bbea42022c213@gmail.com
Signed-off-by: Vitaly Wool <vitalywool@gmail.com>
Reviewed-by: Dan Streetman <ddstreet@ieee.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:54 -08:00
Dan Williams
220ced1676 mm: fix get_user_pages() vs device-dax pud mappings
A new unit test for the device-dax 1GB enabling currently fails with
this warning before hanging the test thread:

 WARNING: CPU: 0 PID: 21 at lib/percpu-refcount.c:155 percpu_ref_switch_to_atomic_rcu+0x1e3/0x1f0
 percpu ref (dax_pmem_percpu_release [dax_pmem]) <= 0 (0) after switching to atomic
 [..]
 CPU: 0 PID: 21 Comm: rcuos/1 Tainted: G           O    4.10.0-rc7-next-20170207+ #944
 [..]
 Call Trace:
  dump_stack+0x86/0xc3
  __warn+0xcb/0xf0
  warn_slowpath_fmt+0x5f/0x80
  ? rcu_nocb_kthread+0x27a/0x510
  ? dax_pmem_percpu_exit+0x50/0x50 [dax_pmem]
  percpu_ref_switch_to_atomic_rcu+0x1e3/0x1f0
  ? percpu_ref_exit+0x60/0x60
  rcu_nocb_kthread+0x339/0x510
  ? rcu_nocb_kthread+0x27a/0x510
  kthread+0x101/0x140

The get_user_pages() path needs to arrange for references to be taken
against the dev_pagemap instance backing the pud mapping.  Refactor the
existing __gup_device_huge_pmd() to also account for the pud case.

Link: http://lkml.kernel.org/r/148653181153.38226.9605457830505509385.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Nilesh Choudhury <nilesh.choudhury@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:54 -08:00
Dave Jiang
c791ace1e7 mm: replace FAULT_FLAG_SIZE with parameter to huge_fault
Since the introduction of FAULT_FLAG_SIZE to the vm_fault flag, it has
been somewhat painful with getting the flags set and removed at the
correct locations.  More than one kernel oops was introduced due to
difficulties of getting the placement correctly.

Remove the flag values and introduce an input parameter to huge_fault
that indicates the size of the page entry.  This makes the code easier
to trace and should avoid the issues we see with the fault flags where
removal of the flag was necessary in the fallback paths.

Link: http://lkml.kernel.org/r/148615748258.43180.1690152053774975329.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Nilesh Choudhury <nilesh.choudhury@oracle.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:54 -08:00
Dave Jiang
9557feee39 dax: support for transparent PUD pages for device DAX
Add transparent huge PUD pages support for device DAX by adding a
pud_fault handler.

Link: http://lkml.kernel.org/r/148545060002.17912.6765687780007547551.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Jan Kara <jack@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Nilesh Choudhury <nilesh.choudhury@oracle.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:54 -08:00
Matthew Wilcox
a00cc7d9dd mm, x86: add support for PUD-sized transparent hugepages
The current transparent hugepage code only supports PMDs.  This patch
adds support for transparent use of PUDs with DAX.  It does not include
support for anonymous pages.  x86 support code also added.

Most of this patch simply parallels the work that was done for huge
PMDs.  The only major difference is how the new ->pud_entry method in
mm_walk works.  The ->pmd_entry method replaces the ->pte_entry method,
whereas the ->pud_entry method works along with either ->pmd_entry or
->pte_entry.  The pagewalk code takes care of locking the PUD before
calling ->pud_walk, so handlers do not need to worry whether the PUD is
stable.

[dave.jiang@intel.com: fix SMP x86 32bit build for native_pud_clear()]
  Link: http://lkml.kernel.org/r/148719066814.31111.3239231168815337012.stgit@djiang5-desk3.ch.intel.com
[dave.jiang@intel.com: native_pud_clear missing on i386 build]
  Link: http://lkml.kernel.org/r/148640375195.69754.3315433724330910314.stgit@djiang5-desk3.ch.intel.com
Link: http://lkml.kernel.org/r/148545059381.17912.8602162635537598445.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Tested-by: Alexander Kapshuk <alexander.kapshuk@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Jan Kara <jack@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Nilesh Choudhury <nilesh.choudhury@oracle.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:54 -08:00