Commit Graph

1031561 Commits

Author SHA1 Message Date
Miaohe Lin
ea3732f7a1 mm/hwpoison: fix potential pte_unmap_unlock pte error
If the first pte is equal to poisoned_pfn, i.e.  check_hwpoisoned_entry()
return 1, the wrong ptep - 1 would be passed to pte_unmap_unlock().

Link: https://lkml.kernel.org/r/20210814105131.48814-3-linmiaohe@huawei.com
Fixes: ad9c59c24095 ("mm,hwpoison: send SIGBUS with error virutal address")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:15 -07:00
Miaohe Lin
ae611d072c mm/hwpoison: remove unneeded variable unmap_success
Patch series "Cleanups and fixup for hwpoison"

This series contains cleanups to remove unneeded variable, fix some
obsolete comments and so on.  Also we fix potential pte_unmap_unlock on
wrong pte.  More details can be found in the respective changelogs.

This patch (of 4):

unmap_success is used to indicate whether page is successfully unmapped
but it's irrelated with ZONE_DEVICE page and unmap_success is always true
here.  Remove this unneeded one.

Link: https://lkml.kernel.org/r/20210814105131.48814-1-linmiaohe@huawei.com
Link: https://lkml.kernel.org/r/20210814105131.48814-2-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:15 -07:00
George G. Davis
1d09510bcc mm/page_isolation: tracing: trace all test_pages_isolated failures
Some test_pages_isolated failure conditions don't include trace points.
For debugging issues caused by "pinned" pages, make sure to trace all
calls whether they succeed or fail.  In this case, a failure case did not
result in a trace point.  So add the missing failure case in
test_pages_isolated traces.

Link: https://lkml.kernel.org/r/20210823202823.13765-1-george_davis@mentor.com
Signed-off-by: George G. Davis <davis.george@siemens.com>
Cc: Eugeniu Rosca <erosca@de.adit-jv.com>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:15 -07:00
Vasily Averin
88dc6f2088 mm/page_alloc.c: use in_task()
Obsoleted in_intrrupt() include task context with disabled BH, it's better
to use in_task() instead.

Link: https://lkml.kernel.org/r/877caa99-1994-5545-92d2-d0bb2e394182@virtuozzo.com
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:15 -07:00
Mike Rapoport
3b446da6be mm/page_alloc: make alloc_node_mem_map() __init rather than __ref
alloc_node_mem_map() is never only called from free_area_init_node() that
is an __init function.

Make the actual alloc_node_mem_map() also __init and its stub version
static inline.

Link: https://lkml.kernel.org/r/20210716064124.31865-1-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:15 -07:00
Nico Pache
b346075fcf mm/page_alloc.c: fix 'zone_id' may be used uninitialized in this function warning
When compiling with -Werror, cc1 will warn that 'zone_id' may be used
uninitialized in this function warning.

Initialize the zone_id as 0.

Its safe to assume that if the code reaches this point it has at least one
numa node with memory, so no need for an assertion before
init_unavilable_range.

Link: https://lkml.kernel.org/r/20210716210336.1114114-1-npache@redhat.com
Fixes: 122e093c17 ("mm/page_alloc: fix memory map initialization for descending nodes")
Signed-off-by: Nico Pache <npache@redhat.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:15 -07:00
Mike Rapoport
08678804e0 memblock: stop poisoning raw allocations
Functions memblock_alloc_exact_nid_raw() and memblock_alloc_try_nid_raw()
are intended for early memory allocation without overhead of zeroing the
allocated memory.  Since these functions were used to allocate the memory
map, they have ended up with addition of a call to page_init_poison() that
poisoned the allocated memory when CONFIG_PAGE_POISON was set.

Since the memory map is allocated using a dedicated memmep_alloc()
function that takes care of the poisoning, remove page poisoning from the
memblock_alloc_*_raw() functions.

Link: https://lkml.kernel.org/r/20210714123739.16493-5-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Michal Simek <monstr@monstr.eu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:15 -07:00
Mike Rapoport
c803b3c8b3 mm: introduce memmap_alloc() to unify memory map allocation
There are several places that allocate memory for the memory map:
alloc_node_mem_map() for FLATMEM, sparse_buffer_init() and
__populate_section_memmap() for SPARSEMEM.

The memory allocated in the FLATMEM case is zeroed and it is never
poisoned, regardless of CONFIG_PAGE_POISON setting.

The memory allocated in the SPARSEMEM cases is not zeroed and it is
implicitly poisoned inside memblock if CONFIG_PAGE_POISON is set.

Introduce memmap_alloc() wrapper for memblock allocators that will be used
for both FLATMEM and SPARSEMEM cases and will makei memory map zeroing and
poisoning consistent for different memory models.

Link: https://lkml.kernel.org/r/20210714123739.16493-4-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Michal Simek <monstr@monstr.eu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:15 -07:00
Mike Rapoport
22e7878102 microblaze: simplify pte_alloc_one_kernel()
The microblaze's implementation of pte_alloc_one_kernel() used
memblock_alloc_try_nid_raw() along with clear_page() to allocated a zeroed
page during early setup.

Replace calls of these functions with a call to memblock_alloc_try_nid()
that already returns zeroed page and respects the same allocation limits
as memblock_alloc_try_nid_raw().

While on it drop early_get_page() wrapper that was only used in
pte_alloc_one_kernel().

Link: https://lkml.kernel.org/r/20210714123739.16493-3-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Michal Simek <monstr@monstr.eu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:15 -07:00
Mike Rapoport
c3ab6baf6a mm/page_alloc: always initialize memory map for the holes
Patch series "mm: ensure consistency of memory map poisoning".

Currently memory map allocation for FLATMEM case does not poison the
struct pages regardless of CONFIG_PAGE_POISON setting.

This happens because allocation of the memory map for FLATMEM and SPARSMEM
use different memblock functions and those that are used for SPARSMEM case
(namely memblock_alloc_try_nid_raw() and memblock_alloc_exact_nid_raw())
implicitly poison the allocated memory.

Another side effect of this implicit poisoning is that early setup code
that uses the same functions to allocate memory burns cycles for the
memory poisoning even if it was not intended.

These patches introduce memmap_alloc() wrapper that ensure that the memory
map allocation is consistent for different memory models.

This patch (of 4):

Currently memory map for the holes is initialized only when SPARSEMEM
memory model is used.  Yet, even with FLATMEM there could be holes in the
physical memory layout that have memory map entries.

For instance, the memory reserved using e820 API on i386 or
"reserved-memory" nodes in device tree would not appear in memblock.memory
and hence the struct pages for such holes will be skipped during memory
map initialization.

These struct pages will be zeroed because the memory map for FLATMEM
systems is allocated with memblock_alloc_node() that clears the allocated
memory.  While zeroed struct pages do not cause immediate problems, the
correct behaviour is to initialize every page using __init_single_page().
Besides, enabling page poison for FLATMEM case will trigger
PF_POISONED_CHECK() unless the memory map is properly initialized.

Make sure init_unavailable_range() is called for both SPARSEMEM and
FLATMEM so that struct pages representing memory holes would appear as
PG_Reserved with any memory layout.

[rppt@kernel.org: fix microblaze]
  Link: https://lkml.kernel.org/r/YQWW3RCE4eWBuMu/@kernel.org

Link: https://lkml.kernel.org/r/20210714123739.16493-1-rppt@kernel.org
Link: https://lkml.kernel.org/r/20210714123739.16493-2-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Cc: Michal Simek <monstr@monstr.eu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:15 -07:00
Andrey Konovalov
f16de0bcdb kasan: test: avoid corrupting memory in kasan_rcu_uaf
kasan_rcu_uaf() writes to freed memory via kasan_rcu_reclaim(), which is
only safe with the GENERIC mode (as it uses quarantine).  For other modes,
this test corrupts kernel memory, which might result in a crash.

Turn the write into a read.

Link: https://lkml.kernel.org/r/b6f2c3bf712d2457c783fa59498225b66a634f62.1628779805.git.andreyknvl@gmail.com
Signed-off-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: 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>
2021-09-03 09:58:15 -07:00
Andrey Konovalov
756e5a47a5 kasan: test: avoid corrupting memory in copy_user_test
copy_user_test() does writes past the allocated object.  As the result, it
corrupts kernel memory, which might lead to crashes with the HW_TAGS mode,
as it neither uses quarantine nor redzones.

(Technically, this test can't yet be enabled with the HW_TAGS mode, but
this will be implemented in the future.)

Adjust the test to only write memory within the aligned kmalloc object.

Link: https://lkml.kernel.org/r/19bf3a5112ee65b7db88dc731643b657b816c5e8.1628779805.git.andreyknvl@gmail.com
Signed-off-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: 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>
2021-09-03 09:58:15 -07:00
Andrey Konovalov
b38fcca339 kasan: test: clean up ksize_uaf
Some KASAN tests use global variables to store function returns values so
that the compiler doesn't optimize away these functions.

ksize_uaf() doesn't call any functions, so it doesn't need to use
kasan_int_result.  Use volatile accesses instead, to be consistent with
other similar tests.

Link: https://lkml.kernel.org/r/a1fc34faca4650f4a6e4dfb3f8d8d82c82eb953a.1628779805.git.andreyknvl@gmail.com
Signed-off-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: 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>
2021-09-03 09:58:15 -07:00
Andrey Konovalov
25b12a58e8 kasan: test: only do kmalloc_uaf_memset for generic mode
kmalloc_uaf_memset() writes to freed memory, which is only safe with the
GENERIC mode (as it uses quarantine).  For other modes, this test corrupts
kernel memory, which might result in a crash.

Only enable kmalloc_uaf_memset() for the GENERIC mode.

Link: https://lkml.kernel.org/r/2e1c87b607b1292556cde3cab2764f108542b60c.1628779805.git.andreyknvl@gmail.com
Signed-off-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: 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>
2021-09-03 09:58:14 -07:00
Andrey Konovalov
1b0668be62 kasan: test: disable kmalloc_memmove_invalid_size for HW_TAGS
The HW_TAGS mode doesn't check memmove for negative size.  As a result,
the kmalloc_memmove_invalid_size test corrupts memory, which can result in
a crash.

Disable this test with HW_TAGS KASAN.

Link: https://lkml.kernel.org/r/088733a06ac21eba29aa85b6f769d2abd74f9638.1628779805.git.andreyknvl@gmail.com
Signed-off-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: 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>
2021-09-03 09:58:14 -07:00
Andrey Konovalov
555999a009 kasan: test: avoid corrupting memory via memset
kmalloc_oob_memset_*() tests do writes past the allocated objects.  As the
result, they corrupt memory, which might lead to crashes with the HW_TAGS
mode, as it neither uses quarantine nor redzones.

Adjust the tests to only write memory within the aligned kmalloc objects.

Also add a comment mentioning that memset tests are designed to touch both
valid and invalid memory.

Link: https://lkml.kernel.org/r/64fd457668a16e7b58d094f14a165f9d5170c5a9.1628779805.git.andreyknvl@gmail.com
Signed-off-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: 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>
2021-09-03 09:58:14 -07:00
Andrey Konovalov
8fbad19bdc kasan: test: avoid writing invalid memory
Multiple KASAN tests do writes past the allocated objects or writes to
freed memory.  Turn these writes into reads to avoid corrupting memory.
Otherwise, these tests might lead to crashes with the HW_TAGS mode, as it
neither uses quarantine nor redzones.

Link: https://lkml.kernel.org/r/c3cd2a383e757e27dd9131635fc7d09a48a49cf9.1628779805.git.andreyknvl@gmail.com
Signed-off-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: 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>
2021-09-03 09:58:14 -07:00
Andrey Konovalov
ab51280571 kasan: test: rework kmalloc_oob_right
Patch series "kasan: test: avoid crashing the kernel with HW_TAGS", v2.

KASAN tests do out-of-bounds and use-after-free accesses.  Running the
tests works fine for the GENERIC mode, as it uses qurantine and redzones.
But the HW_TAGS mode uses neither, and running the tests might crash the
kernel.

Rework the tests to avoid corrupting kernel memory.

This patch (of 8):

Rework kmalloc_oob_right() to do these bad access checks:

1. An unaligned access one byte past the requested kmalloc size
   (can only be detected by KASAN_GENERIC).
2. An aligned access into the first out-of-bounds granule that falls
   within the aligned kmalloc object.
3. Out-of-bounds access past the aligned kmalloc object.

Test #3 deliberately uses a read access to avoid corrupting memory.
Otherwise, this test might lead to crashes with the HW_TAGS mode, as it
neither uses quarantine nor redzones.

Link: https://lkml.kernel.org/r/cover.1628779805.git.andreyknvl@gmail.com
Link: https://lkml.kernel.org/r/474aa8b7b538c6737a4c6d0090350af2e1776bef.1628779805.git.andreyknvl@gmail.com
Signed-off-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:14 -07:00
Woody Lin
c9d1af2b78 mm/kasan: move kasan.fault to mm/kasan/report.c
Move the boot parameter 'kasan.fault' from hw_tags.c to report.c, so it
can support all KASAN modes - generic, and both tag-based.

Link: https://lkml.kernel.org/r/20210713010536.3161822-1-woodylin@google.com
Signed-off-by: Woody Lin <woodylin@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:14 -07:00
Chen Wandun
f181234a5a mm/vmalloc: fix wrong behavior in vread
commit f608788cd2 ("mm/vmalloc: use rb_tree instead of list for vread()
lookups") use rb_tree instread of list to speed up lookup, but function
__find_vmap_area is try to find a vmap_area that include target address,
if target address is smaller than the leftmost node in vmap_area_root, it
will return NULL, then vread will read nothing.  This behavior is
different from the primitive semantics.

The correct way is find the first vmap_are that bigger than target addr,
that is what function find_vmap_area_exceed_addr does.

Link: https://lkml.kernel.org/r/20210714015959.3204871-1-chenwandun@huawei.com
Fixes: f608788cd2 ("mm/vmalloc: use rb_tree instead of list for vread() lookups")
Signed-off-by: Chen Wandun <chenwandun@huawei.com>
Reported-by: Hulk Robot <hulkci@huawei.com>
Cc: Serapheim Dimitropoulos <serapheim.dimitro@delphix.com>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:14 -07:00
Uladzislau Rezki (Sony)
f8bcbecfb6 lib/test_vmalloc.c: add a new 'nr_pages' parameter
In order to simulate different fixed sizes for vmalloc allocation
introduce a new parameter that sets number of pages to be allocated for
the "fix_size_alloc_test" test.

By default 1 page is used unless a different number is specified over the
new parameter.

Link: https://lkml.kernel.org/r/20210710194151.21370-1-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:14 -07:00
Uladzislau Rezki (Sony)
12e376a6f8 mm/vmalloc: remove gfpflags_allow_blocking() check
Get rid of gfpflags_allow_blocking() check from the vmalloc() path as it
is supposed to be sleepable anyway.  Thus remove it from the
alloc_vmap_area() as well as from the vm_area_alloc_pages().

Link: https://lkml.kernel.org/r/20210707182639.31282-2-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:14 -07:00
Uladzislau Rezki (Sony)
343ab8178f mm/vmalloc: use batched page requests in bulk-allocator
In case of simultaneous vmalloc allocations, for example it is 1GB and 12
CPUs my system is able to hit "BUG: soft lockup" for !CONFIG_PREEMPT
kernel.

  RIP: 0010:__alloc_pages_bulk+0xa9f/0xbb0
  Call Trace:
   __vmalloc_node_range+0x11c/0x2d0
   __vmalloc_node+0x4b/0x70
   fix_size_alloc_test+0x44/0x60 [test_vmalloc]
   test_func+0xe7/0x1f0 [test_vmalloc]
   kthread+0x11a/0x140
   ret_from_fork+0x22/0x30

To address this issue invoke a bulk-allocator many times until all pages
are obtained, i.e.  do batched page requests adding cond_resched()
meanwhile to reschedule.  Batched value is hard-coded and is 100 pages per
call.

Link: https://lkml.kernel.org/r/20210707182639.31282-1-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:14 -07:00
Miles Chen
bdbda73550 mm/sparse: clarify pgdat_to_phys
Clarify pgdat_to_phys() by testing if
pgdat == &contig_page_data when CONFIG_NUMA=n.

We only expect contig_page_data in such case, so we
use &contig_page_data directly instead of pgdat.

No functional change intended when CONFIG_BUG_VM=n.

Comment from Mark [1]:
"
... and I reckon it'd be clearer and more robust to define
pgdat_to_phys() in the same ifdefs as contig_page_data so
that these, stay in-sync. e.g. have:

| #ifdef CONFIG_NUMA
| #define pgdat_to_phys(x)	virt_to_phys(x)
| #else /* CONFIG_NUMA */
|
| extern struct pglist_data contig_page_data;
| ...
| #define pgdat_to_phys(x)	__pa_symbol(&contig_page_data)
|
| #endif /* CONIFIG_NUMA */
"

[1] https://lore.kernel.org/linux-arm-kernel/20210615131902.GB47121@C02TD0UTHF1T.local/

Link: https://lkml.kernel.org/r/20210723123342.26406-1-miles.chen@mediatek.com
Signed-off-by: Miles Chen <miles.chen@mediatek.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:14 -07:00
Matthew Wilcox
e0dbb2bccf include/linux/mmzone.h: avoid a warning in sparse memory support
cppcheck warns that we're possibly losing information by shifting an int.
It's a false positive, because we don't allow for a NUMA node ID that
large, but if we ever change SECTION_NID_SHIFT, it could become a problem,
and in any case this is usually a legitimate warning.  Fix it by adding
the necessary cast, which makes the compiler generate the right code.

Link: https://lkml.kernel.org/r/YOya+aBZFFmC476e@casper.infradead.org
Link: https://lkml.kernel.org/r/202107130348.6LsVT9Nc-lkp@intel.com
Cc: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:14 -07:00
Naoya Horiguchi
01c8d337d1 mm/sparse: set SECTION_NID_SHIFT to 6
Currently SECTION_NID_SHIFT is set to 3, which is incorrect because bit 3
and 4 can be overlapped by sub-field for early NID, and can be
unexpectedly set on NUMA systems.  There are a few non-critical issues
related to this:

- Having SECTION_TAINT_ZONE_DEVICE set for wrong sections forces
  pfn_to_online_page() through the slow path, but doesn't actually break
  the kernel.

- A kdump generation tool like makedumpfile uses this field to calculate
  the physical address to read.  So wrong bits can make the tool access to
  wrong address and fail to create kdump.  This can be avoided by the
  tool, so it's not critical.

To fix it, set SECTION_NID_SHIFT to 6 which is the minimum number of
available bits of section flag field.

Link: https://lkml.kernel.org/r/20210707045548.810271-1-naoya.horiguchi@linux.dev
Fixes: 1f90a3477d ("mm: teach pfn_to_online_page() about ZONE_DEVICE section collisions")
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reported-by: Kazuhito Hagio <k-hagio-ab@nec.com>
Suggested-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Wang Wensheng <wangwensheng4@huawei.com>
Cc: Rui Xiang <rui.xiang@huawei.com>
Cc: Kazu <k-hagio-ab@nec.com>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:14 -07:00
Ohhoon Kwon
11e02d3729 mm: sparse: remove __section_nr() function
As the last users of __section_nr() are gone, let's remove unused function
__section_nr().

Link: https://lkml.kernel.org/r/20210707150212.855-4-ohoono.kwon@samsung.com
Signed-off-by: Ohhoon Kwon <ohoono.kwon@samsung.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:14 -07:00
Ohhoon Kwon
fc1f5e980a mm: sparse: pass section_nr to find_memory_block
With CONFIG_SPARSEMEM_EXTREME enabled, __section_nr() which converts
mem_section to section_nr could be costly since it iterates all section
roots to check if the given mem_section is in its range.

On the other hand, __nr_to_section() which converts section_nr to
mem_section can be done in O(1).

Let's pass section_nr instead of mem_section ptr to find_memory_block() in
order to reduce needless iterations.

Link: https://lkml.kernel.org/r/20210707150212.855-3-ohoono.kwon@samsung.com
Signed-off-by: Ohhoon Kwon <ohoono.kwon@samsung.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:14 -07:00
Ohhoon Kwon
a1bc561bb2 mm: sparse: pass section_nr to section_mark_present
Patch series "mm: sparse: remove __section_nr() function", v4.

This patch (of 3):

With CONFIG_SPARSEMEM_EXTREME enabled, __section_nr() which converts
mem_section to section_nr could be costly since it iterates all section
roots to check if the given mem_section is in its range.

Since both callers of section_mark_present already know section_nr, let's
also pass section_nr as well as mem_section in order to reduce costly
translation.

Link: https://lkml.kernel.org/r/20210707150212.855-1-ohoono.kwon@samsung.com
Link: https://lkml.kernel.org/r/20210707150212.855-2-ohoono.kwon@samsung.com
Signed-off-by: Ohhoon Kwon <ohoono.kwon@samsung.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:14 -07:00
Muchun Song
cdcfc631c8 mm/bootmem_info.c: mark __init on register_page_bootmem_info_section
register_page_bootmem_info_section() is only called from __init functions,
so mark it __init as well.

Link: https://lkml.kernel.org/r/20210817042221.77172-1-songmuchun@bytedance.com
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:14 -07:00
Chen Wandun
5e22928abe mm/mremap: fix memory account on do_munmap() failure
mremap will account the delta between new_len and old_len in
vma_to_resize, and then call move_vma when expanding an existing memory
mapping.  In function move_vma, there are two scenarios when calling
do_munmap:

1. move_page_tables from old_addr to new_addr success
2. move_page_tables from old_addr to new_addr fail

In first scenario, it should account old_len if do_munmap fail, because
the delta has already been accounted.

In second scenario, new_addr/new_len will assign to old_addr/old_len if
move_page_table fail, so do_munmap is try to unmap new_addr actually, if
do_munmap fail, it should account the new_len, because error code will be
return from move_vma, and delta will be unaccounted.  What'more, because
of new_len == old_len, so account old_len also is OK.

In summary, account old_len will be correct if do_munmap fail.

Link: https://lkml.kernel.org/r/20210717101942.120607-1-chenwandun@huawei.com
Fixes: 51df7bcb61 ("mm/mremap: account memory on do_munmap() failure")
Signed-off-by: Chen Wandun <chenwandun@huawei.com>
Acked-by: Dmitry Safonov <dima@arista.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:14 -07:00
Liam R. Howlett
9b593cb202 remap_file_pages: Use vma_lookup() instead of find_vma()
Using vma_lookup() verifies the start address is contained in the found vma.
This results in easier to read code.

Link: https://lkml.kernel.org/r/20210817135234.1550204-1-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:14 -07:00
Luigi Rizzo
5b78ed24e8 mm/pagemap: add mmap_assert_locked() annotations to find_vma*()
find_vma() and variants need protection when used.  This patch adds
mmap_assert_lock() calls in the functions.

To make sure the invariant is satisfied, we also need to add a
mmap_read_lock() around the get_user_pages_remote() call in
get_arg_page().  The lock is not strictly necessary because the mm has
been newly created, but the extra cost is limited because the same mutex
was also acquired shortly before in __bprm_mm_init(), so it is hot and
uncontended.

[penguin-kernel@i-love.sakura.ne.jp: TOMOYO needs the same protection which get_arg_page() needs]
  Link: https://lkml.kernel.org/r/58bb6bf7-a57e-8a40-e74b-39584b415152@i-love.sakura.ne.jp

Link: https://lkml.kernel.org/r/20210731175341.3458608-1-lrizzo@google.com
Signed-off-by: Luigi Rizzo <lrizzo@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:13 -07:00
Greg Kroah-Hartman
e15710bf04 mm: change fault_in_pages_* to have an unsigned size parameter
fault_in_pages_writeable() and fault_in_pages_readable() treat the size
parameter as unsigned, doing pointer math with the value, so make this
explicit and set it to be a size_t type which all callers currently treat
it as anyway.

This solves the issue where static checkers get nervous seeing pointer
arithmetic happening with a signed value.

Link: https://lkml.kernel.org/r/20210727111136.457638-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reported-by: Jordy Zomer <jordy@pwning.systems>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Howells <dhowells@redhat.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: "Darrick J. Wong" <djwong@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:13 -07:00
Huang Ying
f00230ff84 mm,do_huge_pmd_numa_page: remove unnecessary TLB flushing code
Before commit c5b5a3dd2c ("mm: thp: refactor NUMA fault handling"), the
TLB flushing is done in do_huge_pmd_numa_page() itself via
flush_tlb_range().

But after commit c5b5a3dd2c ("mm: thp: refactor NUMA fault handling"),
the TLB flushing is done in migrate_pages() as in the following code path
anyway.

do_huge_pmd_numa_page
  migrate_misplaced_page
    migrate_pages

So now, the TLB flushing code in do_huge_pmd_numa_page() becomes
unnecessary.  So the code is deleted in this patch to simplify the code.
This is only code cleanup, there's no visible performance difference.

The mmu_notifier_invalidate_range() in do_huge_pmd_numa_page() is
deleted too.  Because migrate_pages() takes care of that too when CPU
TLB is flushed.

Link: https://lkml.kernel.org/r/20210720065529.716031-1-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:13 -07:00
Christoph Hellwig
f358afc52c mm: remove flush_kernel_dcache_page
flush_kernel_dcache_page is a rather confusing interface that implements a
subset of flush_dcache_page by not being able to properly handle page
cache mapped pages.

The only callers left are in the exec code as all other previous callers
were incorrect as they could have dealt with page cache pages.  Replace
the calls to flush_kernel_dcache_page with calls to flush_dcache_page,
which for all architectures does either exactly the same thing, can
contains one or more of the following:

 1) an optimization to defer the cache flush for page cache pages not
    mapped into userspace
 2) additional flushing for mapped page cache pages if cache aliases
    are possible

Link: https://lkml.kernel.org/r/20210712060928.4161649-7-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Cc: Alex Shi <alexs@kernel.org>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Cercueil <paul@crapouillou.net>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Yoshinori Sato <ysato@users.osdn.me>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:13 -07:00
Christoph Hellwig
0e84f5dbf8 scatterlist: replace flush_kernel_dcache_page with flush_dcache_page
Pages used in scatterlist can be mapped page cache pages (and often are),
so we must use flush_dcache_page here instead of the more limited
flush_kernel_dcache_page that is intended for highmem pages only.

Also remove the PageSlab check given that page_mapping_file as used by the
flush_dcache_page implementations already contains that check.

Link: https://lkml.kernel.org/r/20210712060928.4161649-5-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Alex Shi <alexs@kernel.org>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Cercueil <paul@crapouillou.net>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Yoshinori Sato <ysato@users.osdn.me>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:13 -07:00
Christoph Hellwig
64a05fe645 mmc: mmc_spi: replace flush_kernel_dcache_page with flush_dcache_page
Pages passed to block drivers can be mapped page cache pages, so we must
use flush_dcache_page here instead of the more limited
flush_kernel_dcache_page that is intended for highmem pages only.

Link: https://lkml.kernel.org/r/20210712060928.4161649-3-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Alex Shi <alexs@kernel.org>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Cercueil <paul@crapouillou.net>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Yoshinori Sato <ysato@users.osdn.me>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:13 -07:00
Christoph Hellwig
79c62de859 mmc: JZ4740: remove the flush_kernel_dcache_page call in jz4740_mmc_read_data
Patch series "_kernel_dcache_page fixes and removal".

While looking to convert the block layer away from kmap_atomic towards
kmap_local_page and prefeably the helpers that abstract it away I noticed
that a few block drivers directly or implicitly call
flush_kernel_dcache_page before kunmapping a page that has been written
to.

flush_kernel_dcache_page is documented to to be used in such cases, but
flush_dcache_page is actually required when the page could be in the page
cache and mapped to userspace, which is pretty much always the case when
kmapping an arbitrary page.  Unfortunately the documentation doesn't
exactly make that clear, which lead to this misused.  And it turns out
that only the copy_strings / copy_string_kernel in the exec code were
actually correct users of flush_kernel_dcache_page, which is why I think
we should just remove it and eat the very minor overhead in exec rather
than confusing poor driver writers.

This patch (of 6):

MIPS now implements flush_kernel_dcache_page (as an alias to
flush_dcache_page).

Link: https://lkml.kernel.org/r/20210712060928.4161649-1-hch@lst.de
Link: https://lkml.kernel.org/r/20210712060928.4161649-2-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Guo Ren <guoren@kernel.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Yoshinori Sato <ysato@users.osdn.me>
Cc: Rich Felker <dalias@libc.org>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Paul Cercueil <paul@crapouillou.net>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Alex Shi <alexs@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:13 -07:00
Colin Ian King
0c52ec9513 selftests: Fix spelling mistake "cann't" -> "cannot"
There is a spelling mistake in an error message. Fix it.

Link: https://lkml.kernel.org/r/20210826121217.12885-1-colin.king@canonical.com
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:13 -07:00
Po-Hsu Lin
6260618e09 selftests/vm: use kselftest skip code for skipped tests
There are several test cases in the vm directory are still using exit 0
when they need to be skipped.  Use the kselftest framework to skip code
instead so it can help us to distinguish the return status.

Criterion to filter out what should be fixed in vm directory:
  grep -r "exit 0" -B1 | grep -i skip

This change might cause some false-positives if people are running these
test scripts directly and only checking their return codes, which will
change from 0 to 4.  However I think the impact should be small as most of
our scripts here are already using this skip code.  And there will be no
such issue if running them with the kselftest framework.

Link: https://lkml.kernel.org/r/20210823073433.37653-1-po-hsu.lin@canonical.com
Signed-off-by: Po-Hsu Lin <po-hsu.lin@canonical.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:13 -07:00
Shakeel Butt
4ba9515d32 memcg: make memcg->event_list_lock irqsafe
The memcg->event_list_lock is usually taken in the normal context but when
the userspace closes the corresponding eventfd, eventfd_release through
memcg_event_wake takes memcg->event_list_lock with interrupts disabled.
This is not an issue on its own but it creates a nested dependency from
eventfd_ctx->wqh.lock to memcg->event_list_lock.

Independently, for unrelated eventfd, eventfd_signal() can be called in
the irq context, thus making eventfd_ctx->wqh.lock an irq lock.  For
example, FPGA DFL driver, VHOST VPDA driver and couple of VFIO drivers.
This will force memcg->event_list_lock to be an irqsafe lock as well.

One way to break the nested dependency between eventfd_ctx->wqh.lock and
memcg->event_list_lock is to add an indirection.  However the simplest
solution would be to make memcg->event_list_lock irqsafe.  This is cgroup
v1 feature, is in maintenance and may get deprecated in near future.  So,
no need to add more code.

BTW this has been discussed previously [1] but there weren't irq users of
eventfd_signal() at the time.

[1] https://www.spinics.net/lists/cgroups/msg06248.html

Link: https://lkml.kernel.org/r/20210830172953.207257-1-shakeelb@google.com
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:13 -07:00
Michal Hocko
5c49cf9ad6 memcg: fix up drain_local_stock comment
Thomas and Vlastimil have noticed that the comment in drain_local_stock
doesn't quite make sense.  It talks about a synchronization with the
memory hotplug but there is no actual memory hotplug involvement here.  I
meant to talk about cpu hotplug here.  Fix that up and hopefuly make the
comment more helpful by referencing the cpu hotplug callback as well.

Link: https://lkml.kernel.org/r/YRDwOhVglJmY7ES5@dhcp22.suse.cz
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:13 -07:00
Miaohe Lin
27fb0956ed mm, memcg: save some atomic ops when flush is already true
Add 'else' to save some atomic ops in obj_stock_flush_required() when
flush is already true.  No functional change intended here.

Link: https://lkml.kernel.org/r/20210807082835.61281-3-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: Roman Gushchin <guro@fb.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Alex Shi <alexs@kernel.org>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:13 -07:00
Miaohe Lin
bec49c067c mm, memcg: remove unused functions
Since commit 2d146aa3aa ("mm: memcontrol: switch to rstat"), last user
of memcg_stat_item_in_bytes() is gone.  And since commit fa40d1ee9f
("mm: vmscan: memcontrol: remove mem_cgroup_select_victim_node()"), only
the declaration of mem_cgroup_select_victim_node() is remained here.
Remove them.

Link: https://lkml.kernel.org/r/20210807082835.61281-2-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: Roman Gushchin <guro@fb.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Alex Shi <alexs@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:13 -07:00
Baolin Wang
37bc3cb9bb mm: memcontrol: set the correct memcg swappiness restriction
Since commit c843966c55 ("mm: allow swappiness that prefers reclaiming
anon over the file workingset") has expended the swappiness value to make
swap to be preferred in some systems.  We should also change the memcg
swappiness restriction to allow memcg swap-preferred.

Link: https://lkml.kernel.org/r/d77469b90c45c49953ccbc51e54a1d465bc18f70.1627626255.git.baolin.wang@linux.alibaba.com
Fixes: c843966c55 ("mm: allow swappiness that prefers reclaiming anon over the file workingset")
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
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>
2021-09-03 09:58:13 -07:00
Vasily Averin
55a68c8239 memcg: replace in_interrupt() by !in_task() in active_memcg()
set_active_memcg() uses in_interrupt() check to select proper storage for
cgroup: pointer on task struct or per-cpu pointer.

It isn't fully correct: obsoleted in_interrupt() includes tasks with
disabled BH.  It's better to use '!in_task()' instead.

Link: https://lkml.org/lkml/2021/7/26/487
Link: https://lkml.kernel.org/r/ed4448b0-4970-616f-7368-ef9dd3cb628d@virtuozzo.com
Fixes: 37d5985c00 ("mm: kmem: prepare remote memcg charging infra for interrupt contexts")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Roman Gushchin <guro@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:13 -07:00
Shakeel Butt
96e51ccf1a memcg: cleanup racy sum avoidance code
We used to have per-cpu memcg and lruvec stats and the readers have to
traverse and sum the stats from each cpu.  This summing was racy and may
expose transient negative values.  So, an explicit check was added to
avoid such scenarios.  Now these stats are moved to rstat infrastructure
and are no more per-cpu, so we can remove the fixup for transient negative
values.

Link: https://lkml.kernel.org/r/20210728012243.3369123-1-shakeelb@google.com
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Roman Gushchin <guro@fb.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:13 -07:00
Vasily Averin
ec403e2ae0 memcg: enable accounting for ldt_struct objects
Each task can request own LDT and force the kernel to allocate up to 64Kb
memory per-mm.

There are legitimate workloads with hundreds of processes and there can be
hundreds of workloads running on large machines.  The unaccounted memory
can cause isolation issues between the workloads particularly on highly
utilized machines.

It makes sense to account for this objects to restrict the host's memory
consumption from inside the memcg-limited container.

Link: https://lkml.kernel.org/r/38010594-50fe-c06d-7cb0-d1f77ca422f3@virtuozzo.com
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Acked-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Yutian Yang <nglaive@gmail.com>
Cc: Zefan Li <lizefan.x@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:13 -07:00
Vasily Averin
c509723ec2 memcg: enable accounting for posix_timers_cache slab
A program may create multiple interval timers using timer_create().  For
each timer the kernel preallocates a "queued real-time signal",
Consequently, the number of timers is limited by the RLIMIT_SIGPENDING
resource limit.  The allocated object is quite small, ~250 bytes, but even
the default signal limits allow to consume up to 100 megabytes per user.

It makes sense to account for them to limit the host's memory consumption
from inside the memcg-limited container.

Link: https://lkml.kernel.org/r/57795560-025c-267c-6b1a-dea852d95530@virtuozzo.com
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Yutian Yang <nglaive@gmail.com>
Cc: Zefan Li <lizefan.x@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:13 -07:00