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[ Upstream commit 701d678599d0c1623aaf4139c03eea260a75b027 ]
In zs_destroy_pool() we call flush_work(&pool->free_work). However, we
have no guarantee that migration isn't happening in the background at
that time.
Since migration can't directly free pages, it relies on free_work being
scheduled to free the pages. But there's nothing preventing an
in-progress migrate from queuing the work *after*
zs_unregister_migration() has called flush_work(). Which would mean
pages still pointing at the inode when we free it.
Since we know at destroy time all objects should be free, no new
migrations can come in (since zs_page_isolate() fails for fully-free
zspages). This means it is sufficient to track a "# isolated zspages"
count by class, and have the destroy logic ensure all such pages have
drained before proceeding. Keeping that state under the class spinlock
keeps the logic straightforward.
In this case a memory leak could lead to an eventual crash if compaction
hits the leaked page. This crash would only occur if people are
changing their zswap backend at runtime (which eventually starts
destruction).
Link: http://lkml.kernel.org/r/20190809181751.219326-2-henryburns@google.com
Fixes: 48b4800a1c6a ("zsmalloc: page migration support")
Signed-off-by: Henry Burns <henryburns@google.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Henry Burns <henrywolfeburns@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Jonathan Adams <jwadams@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 1a87aa03597efa9641e92875b883c94c7f872ccb upstream.
In zs_page_migrate() we call putback_zspage() after we have finished
migrating all pages in this zspage. However, the return value is
ignored. If a zs_free() races in between zs_page_isolate() and
zs_page_migrate(), freeing the last object in the zspage,
putback_zspage() will leave the page in ZS_EMPTY for potentially an
unbounded amount of time.
To fix this, we need to do the same thing as zs_page_putback() does:
schedule free_work to occur.
To avoid duplicated code, move the sequence to a new
putback_zspage_deferred() function which both zs_page_migrate() and
zs_page_putback() call.
Link: http://lkml.kernel.org/r/20190809181751.219326-1-henryburns@google.com
Fixes: 48b4800a1c6a ("zsmalloc: page migration support")
Signed-off-by: Henry Burns <henryburns@google.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Henry Burns <henrywolfeburns@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Jonathan Adams <jwadams@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f7da677bc6e72033f0981b9d58b5c5d409fa641e upstream.
THP splitting path is missing the split_page_owner() call that
split_page() has.
As a result, split THP pages are wrongly reported in the page_owner file
as order-9 pages. Furthermore when the former head page is freed, the
remaining former tail pages are not listed in the page_owner file at
all. This patch fixes that by adding the split_page_owner() call into
__split_huge_page().
Link: http://lkml.kernel.org/r/20190820131828.22684-2-vbabka@suse.cz
Fixes: a9627bc5e34e ("mm/page_owner: introduce split_page_owner and replace manual handling")
Reported-by: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 951531691c4bcaa59f56a316e018bc2ff1ddf855 upstream.
Currently, when checking to see if accessing n bytes starting at address
"ptr" will cause a wraparound in the memory addresses, the check in
check_bogus_address() adds an extra byte, which is incorrect, as the
range of addresses that will be accessed is [ptr, ptr + (n - 1)].
This can lead to incorrectly detecting a wraparound in the memory
address, when trying to read 4 KB from memory that is mapped to the the
last possible page in the virtual address space, when in fact, accessing
that range of memory would not cause a wraparound to occur.
Use the memory range that will actually be accessed when considering if
accessing a certain amount of bytes will cause the memory address to
wrap around.
Link: http://lkml.kernel.org/r/1564509253-23287-1-git-send-email-isaacm@codeaurora.org
Fixes: f5509cc18daa ("mm: Hardened usercopy")
Signed-off-by: Prasad Sodagudi <psodagud@codeaurora.org>
Signed-off-by: Isaac J. Manjarres <isaacm@codeaurora.org>
Co-developed-by: Prasad Sodagudi <psodagud@codeaurora.org>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Trilok Soni <tsoni@codeaurora.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[kees: backport to v4.9]
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3f8fd02b1bf1d7ba964485a56f2f4b53ae88c167 upstream.
On x86-32 with PTI enabled, parts of the kernel page-tables are not shared
between processes. This can cause mappings in the vmalloc/ioremap area to
persist in some page-tables after the region is unmapped and released.
When the region is re-used the processes with the old mappings do not fault
in the new mappings but still access the old ones.
This causes undefined behavior, in reality often data corruption, kernel
oopses and panics and even spontaneous reboots.
Fix this problem by activly syncing unmaps in the vmalloc/ioremap area to
all page-tables in the system before the regions can be re-used.
References: https://bugzilla.suse.com/show_bug.cgi?id=1118689
Fixes: 5d72b4fba40ef ('x86, mm: support huge I/O mapping capability I/F')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lkml.kernel.org/r/20190719184652.11391-4-joro@8bytes.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 59ea6d06cfa9247b586a695c21f94afa7183af74 upstream.
When fixing the race conditions between the coredump and the mmap_sem
holders outside the context of the process, we focused on
mmget_not_zero()/get_task_mm() callers in 04f5866e41fb70 ("coredump: fix
race condition between mmget_not_zero()/get_task_mm() and core
dumping"), but those aren't the only cases where the mmap_sem can be
taken outside of the context of the process as Michal Hocko noticed
while backporting that commit to older -stable kernels.
If mmgrab() is called in the context of the process, but then the
mm_count reference is transferred outside the context of the process,
that can also be a problem if the mmap_sem has to be taken for writing
through that mm_count reference.
khugepaged registration calls mmgrab() in the context of the process,
but the mmap_sem for writing is taken later in the context of the
khugepaged kernel thread.
collapse_huge_page() after taking the mmap_sem for writing doesn't
modify any vma, so it's not obvious that it could cause a problem to the
coredump, but it happens to modify the pmd in a way that breaks an
invariant that pmd_trans_huge_lock() relies upon. collapse_huge_page()
needs the mmap_sem for writing just to block concurrent page faults that
call pmd_trans_huge_lock().
Specifically the invariant that "!pmd_trans_huge()" cannot become a
"pmd_trans_huge()" doesn't hold while collapse_huge_page() runs.
The coredump will call __get_user_pages() without mmap_sem for reading,
which eventually can invoke a lockless page fault which will need a
functional pmd_trans_huge_lock().
So collapse_huge_page() needs to use mmget_still_valid() to check it's
not running concurrently with the coredump... as long as the coredump
can invoke page faults without holding the mmap_sem for reading.
This has "Fixes: khugepaged" to facilitate backporting, but in my view
it's more a bug in the coredump code that will eventually have to be
rewritten to stop invoking page faults without the mmap_sem for reading.
So the long term plan is still to drop all mmget_still_valid().
Link: http://lkml.kernel.org/r/20190607161558.32104-1-aarcange@redhat.com
Fixes: ba76149f47d8 ("thp: khugepaged")
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reported-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[Ajay: Just adjusted to apply on v4.9]
Signed-off-by: Ajay Kaher <akaher@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 04f5866e41fb70690e28397487d8bd8eea7d712a upstream.
The core dumping code has always run without holding the mmap_sem for
writing, despite that is the only way to ensure that the entire vma
layout will not change from under it. Only using some signal
serialization on the processes belonging to the mm is not nearly enough.
This was pointed out earlier. For example in Hugh's post from Jul 2017:
https://lkml.kernel.org/r/alpine.LSU.2.11.1707191716030.2055@eggly.anvils
"Not strictly relevant here, but a related note: I was very surprised
to discover, only quite recently, how handle_mm_fault() may be called
without down_read(mmap_sem) - when core dumping. That seems a
misguided optimization to me, which would also be nice to correct"
In particular because the growsdown and growsup can move the
vm_start/vm_end the various loops the core dump does around the vma will
not be consistent if page faults can happen concurrently.
Pretty much all users calling mmget_not_zero()/get_task_mm() and then
taking the mmap_sem had the potential to introduce unexpected side
effects in the core dumping code.
Adding mmap_sem for writing around the ->core_dump invocation is a
viable long term fix, but it requires removing all copy user and page
faults and to replace them with get_dump_page() for all binary formats
which is not suitable as a short term fix.
For the time being this solution manually covers the places that can
confuse the core dump either by altering the vma layout or the vma flags
while it runs. Once ->core_dump runs under mmap_sem for writing the
function mmget_still_valid() can be dropped.
Allowing mmap_sem protected sections to run in parallel with the
coredump provides some minor parallelism advantage to the swapoff code
(which seems to be safe enough by never mangling any vma field and can
keep doing swapins in parallel to the core dumping) and to some other
corner case.
In order to facilitate the backporting I added "Fixes: 86039bd3b4e6"
however the side effect of this same race condition in /proc/pid/mem
should be reproducible since before 2.6.12-rc2 so I couldn't add any
other "Fixes:" because there's no hash beyond the git genesis commit.
Because find_extend_vma() is the only location outside of the process
context that could modify the "mm" structures under mmap_sem for
reading, by adding the mmget_still_valid() check to it, all other cases
that take the mmap_sem for reading don't need the new check after
mmget_not_zero()/get_task_mm(). The expand_stack() in page fault
context also doesn't need the new check, because all tasks under core
dumping are frozen.
Link: http://lkml.kernel.org/r/20190325224949.11068-1-aarcange@redhat.com
Fixes: 86039bd3b4e6 ("userfaultfd: add new syscall to provide memory externalization")
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reported-by: Jann Horn <jannh@google.com>
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Jann Horn <jannh@google.com>
Acked-by: Jason Gunthorpe <jgg@mellanox.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[akaher@vmware.com: stable 4.9 backport
- handle binder_update_page_range - mhocko@suse.com]
Signed-off-by: Ajay Kaher <akaher@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit c633324e311243586675e732249339685e5d6faa ]
The description of cma_declare_contiguous() indicates that if the
'fixed' argument is true the reserved contiguous area must be exactly at
the address of the 'base' argument.
However, the function currently allows the 'base', 'size', and 'limit'
arguments to be silently adjusted to meet alignment constraints. This
commit enforces the documented behavior through explicit checks that
return an error if the region does not fit within a specified region.
Link: http://lkml.kernel.org/r/1561422051-16142-1-git-send-email-opendmb@gmail.com
Fixes: 5ea3b1b2f8ad ("cma: add placement specifier for "cma=" kernel parameter")
Signed-off-by: Doug Berger <opendmb@gmail.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Cc: Yue Hu <huyue2@yulong.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Peng Fan <peng.fan@nxp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 543bdb2d825fe2400d6e951f1786d92139a16931 ]
Make mmu_notifier_register() safer by issuing a memory barrier before
registering a new notifier. This fixes a theoretical bug on weakly
ordered CPUs. For example, take this simplified use of notifiers by a
driver:
my_struct->mn.ops = &my_ops; /* (1) */
mmu_notifier_register(&my_struct->mn, mm)
...
hlist_add_head(&mn->hlist, &mm->mmu_notifiers); /* (2) */
...
Once mmu_notifier_register() releases the mm locks, another thread can
invalidate a range:
mmu_notifier_invalidate_range()
...
hlist_for_each_entry_rcu(mn, &mm->mmu_notifiers, hlist) {
if (mn->ops->invalidate_range)
The read side relies on the data dependency between mn and ops to ensure
that the pointer is properly initialized. But the write side doesn't have
any dependency between (1) and (2), so they could be reordered and the
readers could dereference an invalid mn->ops. mmu_notifier_register()
does take all the mm locks before adding to the hlist, but those have
acquire semantics which isn't sufficient.
By calling hlist_add_head_rcu() instead of hlist_add_head() we update the
hlist using a store-release, ensuring that readers see prior
initialization of my_struct. This situation is better illustated by
litmus test MP+onceassign+derefonce.
Link: http://lkml.kernel.org/r/20190502133532.24981-1-jean-philippe.brucker@arm.com
Fixes: cddb8a5c14aa ("mmu-notifiers: core")
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0874bb49bb21bf24deda853e8bf61b8325e24bcb ]
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 <swkhack@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 745e10146c31b1c6ed3326286704ae251b17f663 ]
"cat /proc/slab_allocators" could hang forever on SMP machines with
kmemleak or object debugging enabled due to other CPUs running do_drain()
will keep making kmemleak_object or debug_objects_cache dirty and unable
to escape the first loop in leaks_show(),
do {
set_store_user_clean(cachep);
drain_cpu_caches(cachep);
...
} while (!is_store_user_clean(cachep));
For example,
do_drain
slabs_destroy
slab_destroy
kmem_cache_free
__cache_free
___cache_free
kmemleak_free_recursive
delete_object_full
__delete_object
put_object
free_object_rcu
kmem_cache_free
cache_free_debugcheck --> dirty kmemleak_object
One approach is to check cachep->name and skip both kmemleak_object and
debug_objects_cache in leaks_show(). The other is to set store_user_clean
after drain_cpu_caches() which leaves a small window between
drain_cpu_caches() and set_store_user_clean() where per-CPU caches could
be dirty again lead to slightly wrong information has been stored but
could also speed up things significantly which sounds like a good
compromise. For example,
# cat /proc/slab_allocators
0m42.778s # 1st approach
0m0.737s # 2nd approach
[akpm@linux-foundation.org: tweak comment]
Link: http://lkml.kernel.org/r/20190411032635.10325-1-cai@lca.pw
Fixes: d31676dfde25 ("mm/slab: alternative implementation for DEBUG_SLAB_LEAK")
Signed-off-by: Qian Cai <cai@lca.pw>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f0fd50504a54f5548eb666dc16ddf8394e44e4b7 ]
If not find zero bit in find_next_zero_bit(), it will return the size
parameter passed in, so the start bit should be compared with bitmap_maxno
rather than cma->count. Although getting maxchunk is working fine due to
zero value of order_per_bit currently, the operation will be stuck if
order_per_bit is set as non-zero.
Link: http://lkml.kernel.org/r/20190319092734.276-1-zbestahu@gmail.com
Signed-off-by: Yue Hu <huyue2@yulong.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Joe Perches <joe@perches.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dmitry Safonov <d.safonov@partner.samsung.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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 1df3a339074e31db95c4790ea9236874b13ccd87 ]
f022d8cb7ec7 ("mm: cma: Don't crash on allocation if CMA area can't be
activated") fixes the crash issue when activation fails via setting
cma->count as 0, same logic exists if bitmap allocation fails.
Link: http://lkml.kernel.org/r/20190325081309.6004-1-zbestahu@gmail.com
Signed-off-by: Yue Hu <huyue2@yulong.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 299c83dce9ea3a79bb4b5511d2cb996b6b8e5111 ]
342332e6a925 ("mm/page_alloc.c: introduce kernelcore=mirror option") and
later patches rewrote the calculation of node spanned pages.
e506b99696a2 ("mem-hotplug: fix node spanned pages when we have a movable
node"), but the current code still has problems,
When we have a node with only zone_movable and the node id is not zero,
the size of node spanned pages is double added.
That's because we have an empty normal zone, and zone_start_pfn or
zone_end_pfn is not between arch_zone_lowest_possible_pfn and
arch_zone_highest_possible_pfn, so we need to use clamp to constrain the
range just like the commit <96e907d13602> (bootmem: Reimplement
__absent_pages_in_range() using for_each_mem_pfn_range()).
e.g.
Zone ranges:
DMA [mem 0x0000000000001000-0x0000000000ffffff]
DMA32 [mem 0x0000000001000000-0x00000000ffffffff]
Normal [mem 0x0000000100000000-0x000000023fffffff]
Movable zone start for each node
Node 0: 0x0000000100000000
Node 1: 0x0000000140000000
Early memory node ranges
node 0: [mem 0x0000000000001000-0x000000000009efff]
node 0: [mem 0x0000000000100000-0x00000000bffdffff]
node 0: [mem 0x0000000100000000-0x000000013fffffff]
node 1: [mem 0x0000000140000000-0x000000023fffffff]
node 0 DMA spanned:0xfff present:0xf9e absent:0x61
node 0 DMA32 spanned:0xff000 present:0xbefe0 absent:0x40020
node 0 Normal spanned:0 present:0 absent:0
node 0 Movable spanned:0x40000 present:0x40000 absent:0
On node 0 totalpages(node_present_pages): 1048446
node_spanned_pages:1310719
node 1 DMA spanned:0 present:0 absent:0
node 1 DMA32 spanned:0 present:0 absent:0
node 1 Normal spanned:0x100000 present:0x100000 absent:0
node 1 Movable spanned:0x100000 present:0x100000 absent:0
On node 1 totalpages(node_present_pages): 2097152
node_spanned_pages:2097152
Memory: 6967796K/12582392K available (16388K kernel code, 3686K rwdata,
4468K rodata, 2160K init, 10444K bss, 5614596K reserved, 0K
cma-reserved)
It shows that the current memory of node 1 is double added.
After this patch, the problem is fixed.
node 0 DMA spanned:0xfff present:0xf9e absent:0x61
node 0 DMA32 spanned:0xff000 present:0xbefe0 absent:0x40020
node 0 Normal spanned:0 present:0 absent:0
node 0 Movable spanned:0x40000 present:0x40000 absent:0
On node 0 totalpages(node_present_pages): 1048446
node_spanned_pages:1310719
node 1 DMA spanned:0 present:0 absent:0
node 1 DMA32 spanned:0 present:0 absent:0
node 1 Normal spanned:0 present:0 absent:0
node 1 Movable spanned:0x100000 present:0x100000 absent:0
On node 1 totalpages(node_present_pages): 1048576
node_spanned_pages:1048576
memory: 6967796K/8388088K available (16388K kernel code, 3686K rwdata,
4468K rodata, 2160K init, 10444K bss, 1420292K reserved, 0K
cma-reserved)
Link: http://lkml.kernel.org/r/1554178276-10372-1-git-send-email-fanglinxu@huawei.com
Signed-off-by: Linxu Fang <fanglinxu@huawei.com>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Pavel Tatashin <pavel.tatashin@microsoft.com>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0919e1b69ab459e06df45d3ba6658d281962db80 ]
When a huge page is allocated, PagePrivate() is set if the allocation
consumed a reservation. When freeing a huge page, PagePrivate is checked.
If set, it indicates the reservation should be restored. PagePrivate
being set at free huge page time mostly happens on error paths.
When huge page reservations are created, a check is made to determine if
the mapping is associated with an explicitly mounted filesystem. If so,
pages are also reserved within the filesystem. The default action when
freeing a huge page is to decrement the usage count in any associated
explicitly mounted filesystem. However, if the reservation is to be
restored the reservation/use count within the filesystem should not be
decrementd. Otherwise, a subsequent page allocation and free for the same
mapping location will cause the file filesystem usage to go 'negative'.
Filesystem Size Used Avail Use% Mounted on
nodev 4.0G -4.0M 4.1G - /opt/hugepool
To fix, when freeing a huge page do not adjust filesystem usage if
PagePrivate() is set to indicate the reservation should be restored.
I did not cc stable as the problem has been around since reserves were
added to hugetlbfs and nobody has noticed.
Link: http://lkml.kernel.org/r/20190328234704.27083-2-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: "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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 8fde12ca79aff9b5ba951fce1a2641901b8d8e64 upstream.
If the page refcount wraps around past zero, it will be freed while
there are still four billion references to it. One of the possible
avenues for an attacker to try to make this happen is by doing direct IO
on a page multiple times. This patch makes get_user_pages() refuse to
take a new page reference if there are already more than two billion
references to the page.
Reported-by: Jann Horn <jannh@google.com>
Acked-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 4.9:
- Add the "err" variable in follow_hugetlb_page()
- Adjust context]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d63206ee32b6e64b0e12d46e5d6004afd9913713 upstream.
When speculatively taking references to a hugepage using
page_cache_add_speculative() in gup_huge_pmd(), it is assumed that the
page returned by pmd_page() is the head page. Although normally true,
this assumption doesn't hold when the hugepage comprises of successive
page table entries such as when using contiguous bit on arm64 at PTE or
PMD levels.
This can be addressed by ensuring that the page passed to
page_cache_add_speculative() is the real head or by de-referencing the
head page within the function.
We take the first approach to keep the usage pattern aligned with
page_cache_get_speculative() where users already pass the appropriate
page, i.e., the de-referenced head.
Apply the same logic to fix gup_huge_[pud|pgd]() as well.
[punit.agrawal@arm.com: fix arm64 ltp failure]
Link: http://lkml.kernel.org/r/20170619170145.25577-5-punit.agrawal@arm.com
Link: http://lkml.kernel.org/r/20170522133604.11392-3-punit.agrawal@arm.com
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Acked-by: Steve Capper <steve.capper@arm.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a3e328556d41bb61c55f9dfcc62d6a826ea97b85 upstream.
When operating on hugepages with DEBUG_VM enabled, the GUP code checks
the compound head for each tail page prior to calling
page_cache_add_speculative. This is broken, because on the fast-GUP
path (where we don't hold any page table locks) we can be racing with a
concurrent invocation of split_huge_page_to_list.
split_huge_page_to_list deals with this race by using page_ref_freeze to
freeze the page and force concurrent GUPs to fail whilst the component
pages are modified. This modification includes clearing the
compound_head field for the tail pages, so checking this prior to a
successful call to page_cache_add_speculative can lead to false
positives: In fact, page_cache_add_speculative *already* has this check
once the page refcount has been successfully updated, so we can simply
remove the broken calls to VM_BUG_ON_PAGE.
Link: http://lkml.kernel.org/r/20170522133604.11392-2-punit.agrawal@arm.com
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Acked-by: Steve Capper <steve.capper@arm.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3e8589963773a5c23e2f1fe4bcad0e9a90b7f471 upstream.
We have a single node system with node 0 disabled:
Scanning NUMA topology in Northbridge 24
Number of physical nodes 2
Skipping disabled node 0
Node 1 MemBase 0000000000000000 Limit 00000000fbff0000
NODE_DATA(1) allocated [mem 0xfbfda000-0xfbfeffff]
This causes crashes in memcg when system boots:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
#PF error: [normal kernel read fault]
...
RIP: 0010:list_lru_add+0x94/0x170
...
Call Trace:
d_lru_add+0x44/0x50
dput.part.34+0xfc/0x110
__fput+0x108/0x230
task_work_run+0x9f/0xc0
exit_to_usermode_loop+0xf5/0x100
It is reproducible as far as 4.12. I did not try older kernels. You have
to have a new enough systemd, e.g. 241 (the reason is unknown -- was not
investigated). Cannot be reproduced with systemd 234.
The system crashes because the size of lru array is never updated in
memcg_update_all_list_lrus and the reads are past the zero-sized array,
causing dereferences of random memory.
The root cause are list_lru_memcg_aware checks in the list_lru code. The
test in list_lru_memcg_aware is broken: it assumes node 0 is always
present, but it is not true on some systems as can be seen above.
So fix this by avoiding checks on node 0. Remember the memcg-awareness by
a bool flag in struct list_lru.
Link: http://lkml.kernel.org/r/20190522091940.3615-1-jslaby@suse.cz
Fixes: 60d3fd32a7a9 ("list_lru: introduce per-memcg lists")
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Suggested-by: Vladimir Davydov <vdavydov.dev@gmail.com>
Acked-by: Vladimir Davydov <vdavydov.dev@gmail.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1b426bac66e6cc83c9f2d92b96e4e72acf43419a upstream.
hugetlb uses a fault mutex hash table to prevent page faults of the
same pages concurrently. The key for shared and private mappings is
different. Shared keys off address_space and file index. Private keys
off mm and virtual address. Consider a private mappings of a populated
hugetlbfs file. A fault will map the page from the file and if needed
do a COW to map a writable page.
Hugetlbfs hole punch uses the fault mutex to prevent mappings of file
pages. It uses the address_space file index key. However, private
mappings will use a different key and could race with this code to map
the file page. This causes problems (BUG) for the page cache remove
code as it expects the page to be unmapped. A sample stack is:
page dumped because: VM_BUG_ON_PAGE(page_mapped(page))
kernel BUG at mm/filemap.c:169!
...
RIP: 0010:unaccount_page_cache_page+0x1b8/0x200
...
Call Trace:
__delete_from_page_cache+0x39/0x220
delete_from_page_cache+0x45/0x70
remove_inode_hugepages+0x13c/0x380
? __add_to_page_cache_locked+0x162/0x380
hugetlbfs_fallocate+0x403/0x540
? _cond_resched+0x15/0x30
? __inode_security_revalidate+0x5d/0x70
? selinux_file_permission+0x100/0x130
vfs_fallocate+0x13f/0x270
ksys_fallocate+0x3c/0x80
__x64_sys_fallocate+0x1a/0x20
do_syscall_64+0x5b/0x180
entry_SYSCALL_64_after_hwframe+0x44/0xa9
There seems to be another potential COW issue/race with this approach
of different private and shared keys as noted in commit 8382d914ebf7
("mm, hugetlb: improve page-fault scalability").
Since every hugetlb mapping (even anon and private) is actually a file
mapping, just use the address_space index key for all mappings. This
results in potentially more hash collisions. However, this should not
be the common case.
Link: http://lkml.kernel.org/r/20190328234704.27083-3-mike.kravetz@oracle.com
Link: http://lkml.kernel.org/r/20190412165235.t4sscoujczfhuiyt@linux-r8p5
Fixes: b5cec28d36f5 ("hugetlbfs: truncate_hugepages() takes a range of pages")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7fc5854f8c6efae9e7624970ab49a1eac2faefb1 upstream.
sync_inodes_sb() can race against cgwb (cgroup writeback) membership
switches and fail to writeback some inodes. For example, if an inode
switches to another wb while sync_inodes_sb() is in progress, the new
wb might not be visible to bdi_split_work_to_wbs() at all or the inode
might jump from a wb which hasn't issued writebacks yet to one which
already has.
This patch adds backing_dev_info->wb_switch_rwsem to synchronize cgwb
switch path against sync_inodes_sb() so that sync_inodes_sb() is
guaranteed to see all the target wbs and inodes can't jump wbs to
escape syncing.
v2: Fixed misplaced rwsem init. Spotted by Jiufei.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Jiufei Xue <xuejiufei@gmail.com>
Link: http://lkml.kernel.org/r/dc694ae2-f07f-61e1-7097-7c8411cee12d@gmail.com
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 134fca9063ad4851de767d1768180e5dede9a881 upstream.
The semantics of what mincore() considers to be resident is not
completely clear, but Linux has always (since 2.3.52, which is when
mincore() was initially done) treated it as "page is available in page
cache".
That's potentially a problem, as that [in]directly exposes
meta-information about pagecache / memory mapping state even about
memory not strictly belonging to the process executing the syscall,
opening possibilities for sidechannel attacks.
Change the semantics of mincore() so that it only reveals pagecache
information for non-anonymous mappings that belog to files that the
calling process could (if it tried to) successfully open for writing;
otherwise we'd be including shared non-exclusive mappings, which
- is the sidechannel
- is not the usecase for mincore(), as that's primarily used for data,
not (shared) text
[jkosina@suse.cz: v2]
Link: http://lkml.kernel.org/r/20190312141708.6652-2-vbabka@suse.cz
[mhocko@suse.com: restructure can_do_mincore() conditions]
Link: http://lkml.kernel.org/r/nycvar.YFH.7.76.1903062342020.19912@cbobk.fhfr.pm
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Josh Snyder <joshs@netflix.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Originally-by: Linus Torvalds <torvalds@linux-foundation.org>
Originally-by: Dominique Martinet <asmadeus@codewreck.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Kevin Easton <kevin@guarana.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Cyril Hrubis <chrubis@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Daniel Gruss <daniel@gruss.cc>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e7701557bfdd81ff44cab13a80439319a735d8e2 upstream.
gcc-7 produces this warning:
mm/kasan/report.c: In function 'kasan_report':
mm/kasan/report.c:351:3: error: 'info.first_bad_addr' may be used uninitialized in this function [-Werror=maybe-uninitialized]
print_shadow_for_address(info->first_bad_addr);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mm/kasan/report.c:360:27: note: 'info.first_bad_addr' was declared here
The code seems fine as we only print info.first_bad_addr when there is a
shadow, and we always initialize it in that case, but this is relatively
hard for gcc to figure out after the latest rework.
Adding an intialization to the most likely value together with the other
struct members shuts up that warning.
Fixes: b235b9808664 ("kasan: unify report headers")
Link: https://patchwork.kernel.org/patch/9641417/
Link: http://lkml.kernel.org/r/20170725152739.4176967-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Alexander Potapenko <glider@google.com>
Suggested-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5c6a84a3f4558a6115fef1b59343c7ae56b3abc3 upstream.
__pa_symbol is the correct API to find the physical address of symbols.
Switch to it to allow for debugging APIs to work correctly. Other
functions such as p*d_populate may call __pa internally. Ensure that the
address passed is in the linear region by calling lm_alias.
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 00206a69ee32f03e6f40837684dcbe475ea02266 upstream.
Since commit ad67b74d2469d9b8 ("printk: hash addresses printed with %p"),
at boot "____ptrval____" is printed instead of actual addresses:
percpu: Embedded 38 pages/cpu @(____ptrval____) s124376 r0 d31272 u524288
Instead of changing the print to "%px", and leaking kernel addresses,
just remove the print completely, cfr. e.g. commit 071929dbdd865f77
("arm64: Stop printing the virtual memory layout").
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: Dennis Zhou <dennis@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e8277b3b52240ec1caad8e6df278863e4bf42eac upstream.
Commit 58bc4c34d249 ("mm/vmstat.c: skip NR_TLB_REMOTE_FLUSH* properly")
depends on skipping vmstat entries with empty name introduced in
7aaf77272358 ("mm: don't show nr_indirectly_reclaimable in
/proc/vmstat") but reverted in b29940c1abd7 ("mm: rename and change
semantics of nr_indirectly_reclaimable_bytes").
So skipping no longer works and /proc/vmstat has misformatted lines " 0".
This patch simply shows debug counters "nr_tlb_remote_*" for UP.
Link: http://lkml.kernel.org/r/155481488468.467.4295519102880913454.stgit@buzz
Fixes: 58bc4c34d249 ("mm/vmstat.c: skip NR_TLB_REMOTE_FLUSH* properly")
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Roman Gushchin <guro@fb.com>
Cc: Jann Horn <jannh@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit afd07389d3f4933c7f7817a92fb5e053d59a3182 ]
One of the vmalloc stress test case triggers the kernel BUG():
<snip>
[60.562151] ------------[ cut here ]------------
[60.562154] kernel BUG at mm/vmalloc.c:512!
[60.562206] invalid opcode: 0000 [#1] PREEMPT SMP PTI
[60.562247] CPU: 0 PID: 430 Comm: vmalloc_test/0 Not tainted 4.20.0+ #161
[60.562293] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[60.562351] RIP: 0010:alloc_vmap_area+0x36f/0x390
<snip>
it can happen due to big align request resulting in overflowing of
calculated address, i.e. it becomes 0 after ALIGN()'s fixup.
Fix it by checking if calculated address is within vstart/vend range.
Link: http://lkml.kernel.org/r/20190124115648.9433-2-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Garnier <thgarnie@google.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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0d3bd18a5efd66097ef58622b898d3139790aa9d ]
In case cma_init_reserved_mem failed, need to free the memblock
allocated by memblock_reserve or memblock_alloc_range.
Quote Catalin's comments:
https://lkml.org/lkml/2019/2/26/482
Kmemleak is supposed to work with the memblock_{alloc,free} pair and it
ignores the memblock_reserve() as a memblock_alloc() implementation
detail. It is, however, tolerant to memblock_free() being called on
a sub-range or just a different range from a previous memblock_alloc().
So the original patch looks fine to me. FWIW:
Link: http://lkml.kernel.org/r/20190227144631.16708-1-peng.fan@nxp.com
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit a7f40cfe3b7ada57af9b62fd28430eeb4a7cfcb7 upstream.
When MPOL_MF_STRICT was specified and an existing page was already on a
node that does not follow the policy, mbind() should return -EIO. But
commit 6f4576e3687b ("mempolicy: apply page table walker on
queue_pages_range()") broke the rule.
And commit c8633798497c ("mm: mempolicy: mbind and migrate_pages support
thp migration") didn't return the correct value for THP mbind() too.
If MPOL_MF_STRICT is set, ignore vma_migratable() to make sure it
reaches queue_pages_to_pte_range() or queue_pages_pmd() to check if an
existing page was already on a node that does not follow the policy.
And, non-migratable vma may be used, return -EIO too if MPOL_MF_MOVE or
MPOL_MF_MOVE_ALL was specified.
Tested with https://github.com/metan-ucw/ltp/blob/master/testcases/kernel/syscalls/mbind/mbind02.c
[akpm@linux-foundation.org: tweak code comment]
Link: http://lkml.kernel.org/r/1553020556-38583-1-git-send-email-yang.shi@linux.alibaba.com
Fixes: 6f4576e3687b ("mempolicy: apply page table walker on queue_pages_range()")
Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Reported-by: Cyril Hrubis <chrubis@suse.cz>
Suggested-by: Kirill A. Shutemov <kirill@shutemov.name>
Acked-by: Rafael Aquini <aquini@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 401592d2e095947344e10ec0623adbcd58934dd4 upstream.
When VM_NO_GUARD is not set area->size includes adjacent guard page,
thus for correct size checking get_vm_area_size() should be used, but
not area->size.
This fixes possible kernel oops when userspace tries to mmap an area on
1 page bigger than was allocated by vmalloc_user() call: the size check
inside remap_vmalloc_range_partial() accounts non-existing guard page
also, so check successfully passes but vmalloc_to_page() returns NULL
(guard page does not physically exist).
The following code pattern example should trigger an oops:
static int oops_mmap(struct file *file, struct vm_area_struct *vma)
{
void *mem;
mem = vmalloc_user(4096);
BUG_ON(!mem);
/* Do not care about mem leak */
return remap_vmalloc_range(vma, mem, 0);
}
And userspace simply mmaps size + PAGE_SIZE:
mmap(NULL, 8192, PROT_WRITE|PROT_READ, MAP_PRIVATE, fd, 0);
Possible candidates for oops which do not have any explicit size
checks:
*** drivers/media/usb/stkwebcam/stk-webcam.c:
v4l_stk_mmap[789] ret = remap_vmalloc_range(vma, sbuf->buffer, 0);
Or the following one:
*** drivers/video/fbdev/core/fbmem.c
static int
fb_mmap(struct file *file, struct vm_area_struct * vma)
...
res = fb->fb_mmap(info, vma);
Where fb_mmap callback calls remap_vmalloc_range() directly without any
explicit checks:
*** drivers/video/fbdev/vfb.c
static int vfb_mmap(struct fb_info *info,
struct vm_area_struct *vma)
{
return remap_vmalloc_range(vma, (void *)info->fix.smem_start, vma->vm_pgoff);
}
Link: http://lkml.kernel.org/r/20190103145954.16942-2-rpenyaev@suse.de
Signed-off-by: Roman Penyaev <rpenyaev@suse.de>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Joe Perches <joe@perches.com>
Cc: "Luis R. Rodriguez" <mcgrof@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 46612b751c4941c5c0472ddf04027e877ae5990f upstream.
When soft_offline_in_use_page() runs on a thp tail page after pmd is
split, we trigger the following VM_BUG_ON_PAGE():
Memory failure: 0x3755ff: non anonymous thp
__get_any_page: 0x3755ff: unknown zero refcount page type 2fffff80000000
Soft offlining pfn 0x34d805 at process virtual address 0x20fff000
page:ffffea000d360140 count:0 mapcount:0 mapping:0000000000000000 index:0x1
flags: 0x2fffff80000000()
raw: 002fffff80000000 ffffea000d360108 ffffea000d360188 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: VM_BUG_ON_PAGE(page_ref_count(page) == 0)
------------[ cut here ]------------
kernel BUG at ./include/linux/mm.h:519!
soft_offline_in_use_page() passed refcount and page lock from tail page
to head page, which is not needed because we can pass any subpage to
split_huge_page().
Naoya had fixed a similar issue in c3901e722b29 ("mm: hwpoison: fix thp
split handling in memory_failure()"). But he missed fixing soft
offline.
Link: http://lkml.kernel.org/r/1551452476-24000-1-git-send-email-zhongjiang@huawei.com
Fixes: 61f5d698cc97 ("mm: re-enable THP")
Signed-off-by: zhongjiang <zhongjiang@huawei.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: <stable@vger.kernel.org> [4.5+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 29b00e609960ae0fcff382f4c7079dd0874a5311 ]
When we made the shmem_reserve_inode call in shmem_link conditional, we
forgot to update the declaration for ret so that it always has a known
value. Dan Carpenter pointed out this deficiency in the original patch.
Fixes: 1062af920c07 ("tmpfs: fix link accounting when a tmpfile is linked in")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Matej Kupljen <matej.kupljen@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 1062af920c07f5b54cf5060fde3339da6df0cf6b ]
tmpfs has a peculiarity of accounting hard links as if they were
separate inodes: so that when the number of inodes is limited, as it is
by default, a user cannot soak up an unlimited amount of unreclaimable
dcache memory just by repeatedly linking a file.
But when v3.11 added O_TMPFILE, and the ability to use linkat() on the
fd, we missed accommodating this new case in tmpfs: "df -i" shows that
an extra "inode" remains accounted after the file is unlinked and the fd
closed and the actual inode evicted. If a user repeatedly links
tmpfiles into a tmpfs, the limit will be hit (ENOSPC) even after they
are deleted.
Just skip the extra reservation from shmem_link() in this case: there's
a sense in which this first link of a tmpfile is then cheaper than a
hard link of another file, but the accounting works out, and there's
still good limiting, so no need to do anything more complicated.
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.1902182134370.7035@eggly.anvils
Fixes: f4e0c30c191 ("allow the temp files created by open() to be linked to")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Reported-by: Matej Kupljen <matej.kupljen@gmail.com>
Acked-by: 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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2c2ade81741c66082f8211f0b96cf509cc4c0218 ]
The basic idea behind ->pagecnt_bias is: If we pre-allocate the maximum
number of references that we might need to create in the fastpath later,
the bump-allocation fastpath only has to modify the non-atomic bias value
that tracks the number of extra references we hold instead of the atomic
refcount. The maximum number of allocations we can serve (under the
assumption that no allocation is made with size 0) is nc->size, so that's
the bias used.
However, even when all memory in the allocation has been given away, a
reference to the page is still held; and in the `offset < 0` slowpath, the
page may be reused if everyone else has dropped their references.
This means that the necessary number of references is actually
`nc->size+1`.
Luckily, from a quick grep, it looks like the only path that can call
page_frag_alloc(fragsz=1) is TAP with the IFF_NAPI_FRAGS flag, which
requires CAP_NET_ADMIN in the init namespace and is only intended to be
used for kernel testing and fuzzing.
To test for this issue, put a `WARN_ON(page_ref_count(page) == 0)` in the
`offset < 0` path, below the virt_to_page() call, and then repeatedly call
writev() on a TAP device with IFF_TAP|IFF_NO_PI|IFF_NAPI_FRAGS|IFF_NAPI,
with a vector consisting of 15 elements containing 1 byte each.
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 414fd080d125408cb15d04ff4907e1dd8145c8c7 ]
For dax pmd, pmd_trans_huge() returns false but pmd_huge() returns true
on x86. So the function works as long as hugetlb is configured.
However, dax doesn't depend on hugetlb.
Link: http://lkml.kernel.org/r/20190111034033.601-1-yuzhao@google.com
Signed-off-by: Yu Zhao <yuzhao@google.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Keith Busch <keith.busch@intel.com>
Cc: "Michael S . Tsirkin" <mst@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 24feb47c5fa5b825efb0151f28906dfdad027e61 ]
If memory end is not aligned with the sparse memory section boundary,
the mapping of such a section is only partly initialized. This may lead
to VM_BUG_ON due to uninitialized struct pages access from
test_pages_in_a_zone() function triggered by memory_hotplug sysfs
handlers.
Here are the the panic examples:
CONFIG_DEBUG_VM_PGFLAGS=y
kernel parameter mem=2050M
--------------------------
page:000003d082008000 is uninitialized and poisoned
page dumped because: VM_BUG_ON_PAGE(PagePoisoned(p))
Call Trace:
test_pages_in_a_zone+0xde/0x160
show_valid_zones+0x5c/0x190
dev_attr_show+0x34/0x70
sysfs_kf_seq_show+0xc8/0x148
seq_read+0x204/0x480
__vfs_read+0x32/0x178
vfs_read+0x82/0x138
ksys_read+0x5a/0xb0
system_call+0xdc/0x2d8
Last Breaking-Event-Address:
test_pages_in_a_zone+0xde/0x160
Kernel panic - not syncing: Fatal exception: panic_on_oops
Fix this by checking whether the pfn to check is within the zone.
[mhocko@suse.com: separated this change from http://lkml.kernel.org/r/20181105150401.97287-2-zaslonko@linux.ibm.com]
Link: http://lkml.kernel.org/r/20190128144506.15603-3-mhocko@kernel.org
[mhocko@suse.com: separated this change from
http://lkml.kernel.org/r/20181105150401.97287-2-zaslonko@linux.ibm.com]
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Tested-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit efad4e475c312456edb3c789d0996d12ed744c13 ]
Patch series "mm, memory_hotplug: fix uninitialized pages fallouts", v2.
Mikhail Zaslonko has posted fixes for the two bugs quite some time ago
[1]. I have pushed back on those fixes because I believed that it is
much better to plug the problem at the initialization time rather than
play whack-a-mole all over the hotplug code and find all the places
which expect the full memory section to be initialized.
We have ended up with commit 2830bf6f05fb ("mm, memory_hotplug:
initialize struct pages for the full memory section") merged and cause a
regression [2][3]. The reason is that there might be memory layouts
when two NUMA nodes share the same memory section so the merged fix is
simply incorrect.
In order to plug this hole we really have to be zone range aware in
those handlers. I have split up the original patch into two. One is
unchanged (patch 2) and I took a different approach for `removable'
crash.
[1] http://lkml.kernel.org/r/20181105150401.97287-2-zaslonko@linux.ibm.com
[2] https://bugzilla.redhat.com/show_bug.cgi?id=1666948
[3] http://lkml.kernel.org/r/20190125163938.GA20411@dhcp22.suse.cz
This patch (of 2):
Mikhail has reported the following VM_BUG_ON triggered when reading sysfs
removable state of a memory block:
page:000003d08300c000 is uninitialized and poisoned
page dumped because: VM_BUG_ON_PAGE(PagePoisoned(p))
Call Trace:
is_mem_section_removable+0xb4/0x190
show_mem_removable+0x9a/0xd8
dev_attr_show+0x34/0x70
sysfs_kf_seq_show+0xc8/0x148
seq_read+0x204/0x480
__vfs_read+0x32/0x178
vfs_read+0x82/0x138
ksys_read+0x5a/0xb0
system_call+0xdc/0x2d8
Last Breaking-Event-Address:
is_mem_section_removable+0xb4/0x190
Kernel panic - not syncing: Fatal exception: panic_on_oops
The reason is that the memory block spans the zone boundary and we are
stumbling over an unitialized struct page. Fix this by enforcing zone
range in is_mem_section_removable so that we never run away from a zone.
Link: http://lkml.kernel.org/r/20190128144506.15603-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Debugged-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Tested-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit cb6acd01e2e43fd8bad11155752b7699c3d0fb76 upstream.
hugetlb pages should only be migrated if they are 'active'. The
routines set/clear_page_huge_active() modify the active state of hugetlb
pages.
When a new hugetlb page is allocated at fault time, set_page_huge_active
is called before the page is locked. Therefore, another thread could
race and migrate the page while it is being added to page table by the
fault code. This race is somewhat hard to trigger, but can be seen by
strategically adding udelay to simulate worst case scheduling behavior.
Depending on 'how' the code races, various BUG()s could be triggered.
To address this issue, simply delay the set_page_huge_active call until
after the page is successfully added to the page table.
Hugetlb pages can also be leaked at migration time if the pages are
associated with a file in an explicitly mounted hugetlbfs filesystem.
For example, consider a two node system with 4GB worth of huge pages
available. A program mmaps a 2G file in a hugetlbfs filesystem. It
then migrates the pages associated with the file from one node to
another. When the program exits, huge page counts are as follows:
node0
1024 free_hugepages
1024 nr_hugepages
node1
0 free_hugepages
1024 nr_hugepages
Filesystem Size Used Avail Use% Mounted on
nodev 4.0G 2.0G 2.0G 50% /var/opt/hugepool
That is as expected. 2G of huge pages are taken from the free_hugepages
counts, and 2G is the size of the file in the explicitly mounted
filesystem. If the file is then removed, the counts become:
node0
1024 free_hugepages
1024 nr_hugepages
node1
1024 free_hugepages
1024 nr_hugepages
Filesystem Size Used Avail Use% Mounted on
nodev 4.0G 2.0G 2.0G 50% /var/opt/hugepool
Note that the filesystem still shows 2G of pages used, while there
actually are no huge pages in use. The only way to 'fix' the filesystem
accounting is to unmount the filesystem
If a hugetlb page is associated with an explicitly mounted filesystem,
this information in contained in the page_private field. At migration
time, this information is not preserved. To fix, simply transfer
page_private from old to new page at migration time if necessary.
There is a related race with removing a huge page from a file and
migration. When a huge page is removed from the pagecache, the
page_mapping() field is cleared, yet page_private remains set until the
page is actually freed by free_huge_page(). A page could be migrated
while in this state. However, since page_mapping() is not set the
hugetlbfs specific routine to transfer page_private is not called and we
leak the page count in the filesystem.
To fix that, check for this condition before migrating a huge page. If
the condition is detected, return EBUSY for the page.
Link: http://lkml.kernel.org/r/74510272-7319-7372-9ea6-ec914734c179@oracle.com
Link: http://lkml.kernel.org/r/20190212221400.3512-1-mike.kravetz@oracle.com
Fixes: bcc54222309c ("mm: hugetlb: introduce page_huge_active")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: <stable@vger.kernel.org>
[mike.kravetz@oracle.com: v2]
Link: http://lkml.kernel.org/r/7534d322-d782-8ac6-1c8d-a8dc380eb3ab@oracle.com
[mike.kravetz@oracle.com: update comment and changelog]
Link: http://lkml.kernel.org/r/420bcfd6-158b-38e4-98da-26d0cd85bd01@oracle.com
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0a1d52994d440e21def1c2174932410b4f2a98a1 upstream.
security_mmap_addr() does a capability check with current_cred(), but
we can reach this code from contexts like a VFS write handler where
current_cred() must not be used.
This can be abused on systems without SMAP to make NULL pointer
dereferences exploitable again.
Fixes: 8869477a49c3 ("security: protect from stack expansion into low vm addresses")
Cc: stable@kernel.org
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3457f4147675108aa83f9f33c136f06bb9f8518f upstream.
is_first_page() is only called from the macro VM_BUG_ON_PAGE() which is
only compiled in as a runtime check when CONFIG_DEBUG_VM is set,
otherwise is checked at compile time and not actually compiled in.
Fixes the following warning, found with Clang:
mm/zsmalloc.c:472:12: warning: function 'is_first_page' is not needed and will not be emitted [-Wunneeded-internal-declaration]
static int is_first_page(struct page *page)
^
Link: http://lkml.kernel.org/r/20170524053859.29059-1-nick.desaulniers@gmail.com
Signed-off-by: Nick Desaulniers <nick.desaulniers@gmail.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3eb95feac113d8ebad5b7b5189a65efcbd95a749 upstream.
zs_stat_inc/dec/get() uses enum zs_stat_type for the stat type, however
some callers pass an enum fullness_group value. Change the type to int to
reflect the actual use of the functions and get rid of 'enum-conversion'
warnings
Link: http://lkml.kernel.org/r/20170731175000.56538-1-mka@chromium.org
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Doug Anderson <dianders@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 050c17f239fd53adb55aa768d4f41bc76c0fe045 upstream.
The system call, get_mempolicy() [1], passes an unsigned long *nodemask
pointer and an unsigned long maxnode argument which specifies the length
of the user's nodemask array in bits (which is rounded up). The manual
page says that if the maxnode value is too small, get_mempolicy will
return EINVAL but there is no system call to return this minimum value.
To determine this value, some programs search /proc/<pid>/status for a
line starting with "Mems_allowed:" and use the number of digits in the
mask to determine the minimum value. A recent change to the way this line
is formatted [2] causes these programs to compute a value less than
MAX_NUMNODES so get_mempolicy() returns EINVAL.
Change get_mempolicy(), the older compat version of get_mempolicy(), and
the copy_nodes_to_user() function to use nr_node_ids instead of
MAX_NUMNODES, thus preserving the defacto method of computing the minimum
size for the nodemask array and the maxnode argument.
[1] http://man7.org/linux/man-pages/man2/get_mempolicy.2.html
[2] https://lore.kernel.org/lkml/1545405631-6808-1-git-send-email-longman@redhat.com
Link: http://lkml.kernel.org/r/20190211180245.22295-1-rcampbell@nvidia.com
Fixes: 4fb8e5b89bcbbbb ("include/linux/nodemask.h: use nr_node_ids (not MAX_NUMNODES) in __nodemask_pr_numnodes()")
Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Suggested-by: Alexander Duyck <alexander.duyck@gmail.com>
Cc: Waiman Long <longman@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Andrew Morton
Henry Burns
Vlastimil Babka
Miles Chen
Isaac J. Manjarres
Joerg Roedel
Andrea Arcangeli
Doug Berger
Jean-Philippe Brucker
Dmitry Vyukov
swkhack
Colin Ian King
Shakeel Butt
Qian Cai
Yue Hu
Linxu Fang
Mike Kravetz
Linus Torvalds
Punit Agrawal
Will Deacon
Jiri Slaby
Tejun Heo
Jiri Kosina
Arnd Bergmann
Laura Abbott
Josh Poimboeuf
Matteo Croce
Konstantin Khlebnikov
Uladzislau Rezki (Sony)
Peng Fan
Yang Shi
Roman Penyaev
zhongjiang
Darrick J. Wong
Jann Horn
Yu Zhao
Mikhail Zaslonko
Michal Hocko
Nick Desaulniers
Matthias Kaehlcke
Ralph Campbell