Commit Graph

17350 Commits

Author SHA1 Message Date
Linus Torvalds 1be5bdf8cd KCSAN updates for v5.17
This series provides KCSAN fixes and also the ability to take memory
 barriers into account for weakly-ordered systems.  This last can increase
 the probability of detecting certain types of data races.
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Merge tag 'kcsan.2022.01.09a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu

Pull KCSAN updates from Paul McKenney:
 "This provides KCSAN fixes and also the ability to take memory barriers
  into account for weakly-ordered systems. This last can increase the
  probability of detecting certain types of data races"

* tag 'kcsan.2022.01.09a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: (29 commits)
  kcsan: Only test clear_bit_unlock_is_negative_byte if arch defines it
  kcsan: Avoid nested contexts reading inconsistent reorder_access
  kcsan: Turn barrier instrumentation into macros
  kcsan: Make barrier tests compatible with lockdep
  kcsan: Support WEAK_MEMORY with Clang where no objtool support exists
  compiler_attributes.h: Add __disable_sanitizer_instrumentation
  objtool, kcsan: Remove memory barrier instrumentation from noinstr
  objtool, kcsan: Add memory barrier instrumentation to whitelist
  sched, kcsan: Enable memory barrier instrumentation
  mm, kcsan: Enable barrier instrumentation
  x86/qspinlock, kcsan: Instrument barrier of pv_queued_spin_unlock()
  x86/barriers, kcsan: Use generic instrumentation for non-smp barriers
  asm-generic/bitops, kcsan: Add instrumentation for barriers
  locking/atomics, kcsan: Add instrumentation for barriers
  locking/barriers, kcsan: Support generic instrumentation
  locking/barriers, kcsan: Add instrumentation for barriers
  kcsan: selftest: Add test case to check memory barrier instrumentation
  kcsan: Ignore GCC 11+ warnings about TSan runtime support
  kcsan: test: Add test cases for memory barrier instrumentation
  kcsan: test: Match reordered or normal accesses
  ...
2022-01-11 09:51:26 -08:00
Linus Torvalds ca1a46d6f5 slab changes for 5.17
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Merge tag 'slab-for-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab

Pull slab updates from Vlastimil Babka:

 - Separate struct slab from struct page - an offshot of the page folio
   work.

   Struct page fields used by slab allocators are moved from struct page
   to a new struct slab, that uses the same physical storage. Similar to
   struct folio, it always is a head page. This brings better type
   safety, separation of large kmalloc allocations from true slabs, and
   cleanup of related objcg code.

 - A SLAB_MERGE_DEFAULT config optimization.

* tag 'slab-for-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab: (33 commits)
  mm/slob: Remove unnecessary page_mapcount_reset() function call
  bootmem: Use page->index instead of page->freelist
  zsmalloc: Stop using slab fields in struct page
  mm/slub: Define struct slab fields for CONFIG_SLUB_CPU_PARTIAL only when enabled
  mm/slub: Simplify struct slab slabs field definition
  mm/sl*b: Differentiate struct slab fields by sl*b implementations
  mm/kfence: Convert kfence_guarded_alloc() to struct slab
  mm/kasan: Convert to struct folio and struct slab
  mm/slob: Convert SLOB to use struct slab and struct folio
  mm/memcg: Convert slab objcgs from struct page to struct slab
  mm: Convert struct page to struct slab in functions used by other subsystems
  mm/slab: Finish struct page to struct slab conversion
  mm/slab: Convert most struct page to struct slab by spatch
  mm/slab: Convert kmem_getpages() and kmem_freepages() to struct slab
  mm/slub: Finish struct page to struct slab conversion
  mm/slub: Convert most struct page to struct slab by spatch
  mm/slub: Convert pfmemalloc_match() to take a struct slab
  mm/slub: Convert __free_slab() to use struct slab
  mm/slub: Convert alloc_slab_page() to return a struct slab
  mm/slub: Convert print_page_info() to print_slab_info()
  ...
2022-01-10 11:58:12 -08:00
Linus Torvalds bfed6efb8e - Add support for handling hw errors in SGX pages: poisoning, recovering
from poison memory and error injection into SGX pages
 
 - A bunch of changes to the SGX selftests to simplify and allow of SGX
 features testing without the need of a whole SGX software stack
 
 - Add a sysfs attribute which is supposed to show the amount of SGX
 memory in a NUMA node, similar to what /proc/meminfo is to normal
 memory
 
 - The usual bunch of fixes and cleanups too
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Merge tag 'x86_sgx_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 SGX updates from Borislav Petkov:

 - Add support for handling hw errors in SGX pages: poisoning,
   recovering from poison memory and error injection into SGX pages

 - A bunch of changes to the SGX selftests to simplify and allow of SGX
   features testing without the need of a whole SGX software stack

 - Add a sysfs attribute which is supposed to show the amount of SGX
   memory in a NUMA node, similar to what /proc/meminfo is to normal
   memory

 - The usual bunch of fixes and cleanups too

* tag 'x86_sgx_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  x86/sgx: Fix NULL pointer dereference on non-SGX systems
  selftests/sgx: Fix corrupted cpuid macro invocation
  x86/sgx: Add an attribute for the amount of SGX memory in a NUMA node
  x86/sgx: Fix minor documentation issues
  selftests/sgx: Add test for multiple TCS entry
  selftests/sgx: Enable multiple thread support
  selftests/sgx: Add page permission and exception test
  selftests/sgx: Rename test properties in preparation for more enclave tests
  selftests/sgx: Provide per-op parameter structs for the test enclave
  selftests/sgx: Add a new kselftest: Unclobbered_vdso_oversubscribed
  selftests/sgx: Move setup_test_encl() to each TEST_F()
  selftests/sgx: Encpsulate the test enclave creation
  selftests/sgx: Dump segments and /proc/self/maps only on failure
  selftests/sgx: Create a heap for the test enclave
  selftests/sgx: Make data measurement for an enclave segment optional
  selftests/sgx: Assign source for each segment
  selftests/sgx: Fix a benign linker warning
  x86/sgx: Add check for SGX pages to ghes_do_memory_failure()
  x86/sgx: Add hook to error injection address validation
  x86/sgx: Hook arch_memory_failure() into mainline code
  ...
2022-01-10 09:44:09 -08:00
Hyeonggon Yoo b01af5c0b0 mm/slob: Remove unnecessary page_mapcount_reset() function call
After commit 401fb12c68 ("mm/sl*b: Differentiate struct slab fields by
sl*b implementations"), we can reorder fields of struct slab depending
on slab allocator.

For now, page_mapcount_reset() is called because page->_mapcount and
slab->units have same offset. But this is not necessary for struct slab.
Use unused field for units instead.

Signed-off-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Link: https://lore.kernel.org/r/20211212065241.GA886691@odroid
2022-01-06 12:27:28 +01:00
Matthew Wilcox (Oracle) c5e97ed154 bootmem: Use page->index instead of page->freelist
page->freelist is for the use of slab.  Using page->index is the same
set of bits as page->freelist, and by using an integer instead of a
pointer, we can avoid casts.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: <x86@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
2022-01-06 12:27:03 +01:00
Matthew Wilcox (Oracle) ffedd09fa9 zsmalloc: Stop using slab fields in struct page
The ->freelist and ->units members of struct page are for the use of
slab only.  I'm not particularly familiar with zsmalloc, so generate the
same code by using page->index to store 'page' (page->index and
page->freelist are at the same offset in struct page).  This should be
cleaned up properly at some point by somebody who is familiar with
zsmalloc.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Minchan Kim <minchan@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
2022-01-06 12:27:03 +01:00
Vlastimil Babka 9c01e9af17 mm/slub: Define struct slab fields for CONFIG_SLUB_CPU_PARTIAL only when enabled
The fields 'next' and 'slabs' are only used when CONFIG_SLUB_CPU_PARTIAL
is enabled. We can put their definition to #ifdef to prevent accidental
use when disabled.

Currenlty show_slab_objects() and slabs_cpu_partial_show() contain code
accessing the slabs field that's effectively dead with
CONFIG_SLUB_CPU_PARTIAL=n through the wrappers slub_percpu_partial() and
slub_percpu_partial_read_once(), but to prevent a compile error, we need
to hide all this code behind #ifdef.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
2022-01-06 12:26:53 +01:00
Vlastimil Babka 662188c3a2 mm/slub: Simplify struct slab slabs field definition
Before commit b47291ef02 ("mm, slub: change percpu partial accounting
from objects to pages") we had to fit two integer fields into a native
word size, so we used short int on 32-bit and int on 64-bit via #ifdef.
After that commit there is only one integer field, so we can simply
define it as int everywhere.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Roman Gushchin <guro@fb.com>
2022-01-06 12:26:45 +01:00
Vlastimil Babka 401fb12c68 mm/sl*b: Differentiate struct slab fields by sl*b implementations
With a struct slab definition separate from struct page, we can go
further and define only fields that the chosen sl*b implementation uses.
This means everything between __page_flags and __page_refcount
placeholders now depends on the chosen CONFIG_SL*B. Some fields exist in
all implementations (slab_list) but can be part of a union in some, so
it's simpler to repeat them than complicate the definition with ifdefs
even more.

The patch doesn't change physical offsets of the fields, although it
could be done later - for example it's now clear that tighter packing in
SLOB could be possible.

This should also prevent accidental use of fields that don't exist in
given implementation. Before this patch virt_to_cache() and
cache_from_obj() were visible for SLOB (albeit not used), although they
rely on the slab_cache field that isn't set by SLOB. With this patch
it's now a compile error, so these functions are now hidden behind
an #ifndef CONFIG_SLOB.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Roman Gushchin <guro@fb.com>
Tested-by: Marco Elver <elver@google.com> # kfence
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: <kasan-dev@googlegroups.com>
2022-01-06 12:26:29 +01:00
Vlastimil Babka 8dae0cfed5 mm/kfence: Convert kfence_guarded_alloc() to struct slab
The function sets some fields that are being moved from struct page to
struct slab so it needs to be converted.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Tested-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: <kasan-dev@googlegroups.com>
2022-01-06 12:26:29 +01:00
Matthew Wilcox (Oracle) 6e48a966df mm/kasan: Convert to struct folio and struct slab
KASAN accesses some slab related struct page fields so we need to
convert it to struct slab. Some places are a bit simplified thanks to
kasan_addr_to_slab() encapsulating the PageSlab flag check through
virt_to_slab().  When resolving object address to either a real slab or
a large kmalloc, use struct folio as the intermediate type for testing
the slab flag to avoid unnecessary implicit compound_head().

[ vbabka@suse.cz: use struct folio, adjust to differences in previous
  patches ]

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Tested-by: Hyeongogn Yoo <42.hyeyoo@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: <kasan-dev@googlegroups.com>
2022-01-06 12:26:14 +01:00
Matthew Wilcox (Oracle) 50757018b4 mm/slob: Convert SLOB to use struct slab and struct folio
Use struct slab throughout the slob allocator. Where non-slab page can
appear use struct folio instead of struct page.

[ vbabka@suse.cz: don't introduce wrappers for PageSlobFree in mm/slab.h
  just for the single callers being wrappers in mm/slob.c ]

[ Hyeonggon Yoo <42.hyeyoo@gmail.com>: fix NULL pointer deference ]

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
2022-01-06 12:26:14 +01:00
Vlastimil Babka 4b5f8d9a89 mm/memcg: Convert slab objcgs from struct page to struct slab
page->memcg_data is used with MEMCG_DATA_OBJCGS flag only for slab pages
so convert all the related infrastructure to struct slab. Also use
struct folio instead of struct page when resolving object pointers.

This is not just mechanistic changing of types and names. Now in
mem_cgroup_from_obj() we use folio_test_slab() to decide if we interpret
the folio as a real slab instead of a large kmalloc, instead of relying
on MEMCG_DATA_OBJCGS bit that used to be checked in page_objcgs_check().
Similarly in memcg_slab_free_hook() where we can encounter
kmalloc_large() pages (here the folio slab flag check is implied by
virt_to_slab()). As a result, page_objcgs_check() can be dropped instead
of converted.

To avoid include cycles, move the inline definition of slab_objcgs()
from memcontrol.h to mm/slab.h.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Roman Gushchin <guro@fb.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: <cgroups@vger.kernel.org>
2022-01-06 12:26:14 +01:00
Vlastimil Babka 40f3bf0cb0 mm: Convert struct page to struct slab in functions used by other subsystems
KASAN, KFENCE and memcg interact with SLAB or SLUB internals through
functions nearest_obj(), obj_to_index() and objs_per_slab() that use
struct page as parameter. This patch converts it to struct slab
including all callers, through a coccinelle semantic patch.

// Options: --include-headers --no-includes --smpl-spacing include/linux/slab_def.h include/linux/slub_def.h mm/slab.h mm/kasan/*.c mm/kfence/kfence_test.c mm/memcontrol.c mm/slab.c mm/slub.c
// Note: needs coccinelle 1.1.1 to avoid breaking whitespace

@@
@@

-objs_per_slab_page(
+objs_per_slab(
 ...
 )
 { ... }

@@
@@

-objs_per_slab_page(
+objs_per_slab(
 ...
 )

@@
identifier fn =~ "obj_to_index|objs_per_slab";
@@

 fn(...,
-   const struct page *page
+   const struct slab *slab
    ,...)
 {
<...
(
- page_address(page)
+ slab_address(slab)
|
- page
+ slab
)
...>
 }

@@
identifier fn =~ "nearest_obj";
@@

 fn(...,
-   struct page *page
+   const struct slab *slab
    ,...)
 {
<...
(
- page_address(page)
+ slab_address(slab)
|
- page
+ slab
)
...>
 }

@@
identifier fn =~ "nearest_obj|obj_to_index|objs_per_slab";
expression E;
@@

 fn(...,
(
- slab_page(E)
+ E
|
- virt_to_page(E)
+ virt_to_slab(E)
|
- virt_to_head_page(E)
+ virt_to_slab(E)
|
- page
+ page_slab(page)
)
  ,...)

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Julia Lawall <julia.lawall@inria.fr>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: <kasan-dev@googlegroups.com>
Cc: <cgroups@vger.kernel.org>
2022-01-06 12:26:13 +01:00
Vlastimil Babka dd35f71a1d mm/slab: Finish struct page to struct slab conversion
Change cache_free_alien() to use slab_nid(virt_to_slab()). Otherwise
just update of comments and some remaining variable names.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
2022-01-06 12:26:10 +01:00
Vlastimil Babka 7981e67efb mm/slab: Convert most struct page to struct slab by spatch
The majority of conversion from struct page to struct slab in SLAB
internals can be delegated to a coccinelle semantic patch. This includes
renaming of variables with 'page' in name to 'slab', and similar.

Big thanks to Julia Lawall and Luis Chamberlain for help with
coccinelle.

// Options: --include-headers --no-includes --smpl-spacing mm/slab.c
// Note: needs coccinelle 1.1.1 to avoid breaking whitespace, and ocaml for the
// embedded script

// build list of functions for applying the next rule
@initialize:ocaml@
@@

let ok_function p =
  not (List.mem (List.hd p).current_element ["kmem_getpages";"kmem_freepages"])

// convert the type in selected functions
@@
position p : script:ocaml() { ok_function p };
@@

- struct page@p
+ struct slab

@@
@@

-PageSlabPfmemalloc(page)
+slab_test_pfmemalloc(slab)

@@
@@

-ClearPageSlabPfmemalloc(page)
+slab_clear_pfmemalloc(slab)

@@
@@

obj_to_index(
 ...,
- page
+ slab_page(slab)
,...)

// for all functions, change any "struct slab *page" parameter to "struct slab
// *slab" in the signature, and generally all occurences of "page" to "slab" in
// the body - with some special cases.
@@
identifier fn;
expression E;
@@

 fn(...,
-   struct slab *page
+   struct slab *slab
    ,...)
 {
<...
(
- int page_node;
+ int slab_node;
|
- page_node
+ slab_node
|
- page_slab(page)
+ slab
|
- page_address(page)
+ slab_address(slab)
|
- page_size(page)
+ slab_size(slab)
|
- page_to_nid(page)
+ slab_nid(slab)
|
- virt_to_head_page(E)
+ virt_to_slab(E)
|
- page
+ slab
)
...>
 }

// rename a function parameter
@@
identifier fn;
expression E;
@@

 fn(...,
-   int page_node
+   int slab_node
    ,...)
 {
<...
- page_node
+ slab_node
...>
 }

// functions converted by previous rules that were temporarily called using
// slab_page(E) so we want to remove the wrapper now that they accept struct
// slab ptr directly
@@
identifier fn =~ "index_to_obj";
expression E;
@@

 fn(...,
- slab_page(E)
+ E
 ,...)

// functions that were returning struct page ptr and now will return struct
// slab ptr, including slab_page() wrapper removal
@@
identifier fn =~ "cache_grow_begin|get_valid_first_slab|get_first_slab";
expression E;
@@

 fn(...)
 {
<...
- slab_page(E)
+ E
...>
 }

// rename any former struct page * declarations
@@
@@

struct slab *
-page
+slab
;

// all functions (with exceptions) with a local "struct slab *page" variable
// that will be renamed to "struct slab *slab"
@@
identifier fn !~ "kmem_getpages|kmem_freepages";
expression E;
@@

 fn(...)
 {
<...
(
- page_slab(page)
+ slab
|
- page_to_nid(page)
+ slab_nid(slab)
|
- kasan_poison_slab(page)
+ kasan_poison_slab(slab_page(slab))
|
- page_address(page)
+ slab_address(slab)
|
- page_size(page)
+ slab_size(slab)
|
- page->pages
+ slab->slabs
|
- page = virt_to_head_page(E)
+ slab = virt_to_slab(E)
|
- virt_to_head_page(E)
+ virt_to_slab(E)
|
- page
+ slab
)
...>
 }

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Roman Gushchin <guro@fb.com>
Tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Julia Lawall <julia.lawall@inria.fr>
Cc: Luis Chamberlain <mcgrof@kernel.org>
2022-01-06 12:26:02 +01:00
Vlastimil Babka 42c0faac31 mm/slab: Convert kmem_getpages() and kmem_freepages() to struct slab
These functions sit at the boundary to page allocator. Also use folio
internally to avoid extra compound_head() when dealing with page flags.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
2022-01-06 12:26:02 +01:00
Vlastimil Babka c2092c1206 mm/slub: Finish struct page to struct slab conversion
Update comments mentioning pages to mention slabs where appropriate.
Also some goto labels.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Roman Gushchin <guro@fb.com>
2022-01-06 12:26:02 +01:00
Vlastimil Babka bb192ed9aa mm/slub: Convert most struct page to struct slab by spatch
The majority of conversion from struct page to struct slab in SLUB
internals can be delegated to a coccinelle semantic patch. This includes
renaming of variables with 'page' in name to 'slab', and similar.

Big thanks to Julia Lawall and Luis Chamberlain for help with
coccinelle.

// Options: --include-headers --no-includes --smpl-spacing include/linux/slub_def.h mm/slub.c
// Note: needs coccinelle 1.1.1 to avoid breaking whitespace, and ocaml for the
// embedded script

// build list of functions to exclude from applying the next rule
@initialize:ocaml@
@@

let ok_function p =
  not (List.mem (List.hd p).current_element ["nearest_obj";"obj_to_index";"objs_per_slab_page";"__slab_lock";"__slab_unlock";"free_nonslab_page";"kmalloc_large_node"])

// convert the type from struct page to struct page in all functions except the
// list from previous rule
// this also affects struct kmem_cache_cpu, but that's ok
@@
position p : script:ocaml() { ok_function p };
@@

- struct page@p
+ struct slab

// in struct kmem_cache_cpu, change the name from page to slab
// the type was already converted by the previous rule
@@
@@

struct kmem_cache_cpu {
...
-struct slab *page;
+struct slab *slab;
...
}

// there are many places that use c->page which is now c->slab after the
// previous rule
@@
struct kmem_cache_cpu *c;
@@

-c->page
+c->slab

@@
@@

struct kmem_cache {
...
- unsigned int cpu_partial_pages;
+ unsigned int cpu_partial_slabs;
...
}

@@
struct kmem_cache *s;
@@

- s->cpu_partial_pages
+ s->cpu_partial_slabs

@@
@@

static void
- setup_page_debug(
+ setup_slab_debug(
 ...)
 {...}

@@
@@

- setup_page_debug(
+ setup_slab_debug(
 ...);

// for all functions (with exceptions), change any "struct slab *page"
// parameter to "struct slab *slab" in the signature, and generally all
// occurences of "page" to "slab" in the body - with some special cases.

@@
identifier fn !~ "free_nonslab_page|obj_to_index|objs_per_slab_page|nearest_obj";
@@
 fn(...,
-   struct slab *page
+   struct slab *slab
    ,...)
 {
<...
- page
+ slab
...>
 }

// similar to previous but the param is called partial_page
@@
identifier fn;
@@

 fn(...,
-   struct slab *partial_page
+   struct slab *partial_slab
    ,...)
 {
<...
- partial_page
+ partial_slab
...>
 }

// similar to previous but for functions that take pointer to struct page ptr
@@
identifier fn;
@@

 fn(...,
-   struct slab **ret_page
+   struct slab **ret_slab
    ,...)
 {
<...
- ret_page
+ ret_slab
...>
 }

// functions converted by previous rules that were temporarily called using
// slab_page(E) so we want to remove the wrapper now that they accept struct
// slab ptr directly
@@
identifier fn =~ "slab_free|do_slab_free";
expression E;
@@

 fn(...,
- slab_page(E)
+ E
  ,...)

// similar to previous but for another pattern
@@
identifier fn =~ "slab_pad_check|check_object";
@@

 fn(...,
- folio_page(folio, 0)
+ slab
  ,...)

// functions that were returning struct page ptr and now will return struct
// slab ptr, including slab_page() wrapper removal
@@
identifier fn =~ "allocate_slab|new_slab";
expression E;
@@

 static
-struct slab *
+struct slab *
 fn(...)
 {
<...
- slab_page(E)
+ E
...>
 }

// rename any former struct page * declarations
@@
@@

struct slab *
(
- page
+ slab
|
- partial_page
+ partial_slab
|
- oldpage
+ oldslab
)
;

// this has to be separate from previous rule as page and page2 appear at the
// same line
@@
@@

struct slab *
-page2
+slab2
;

// similar but with initial assignment
@@
expression E;
@@

struct slab *
(
- page
+ slab
|
- flush_page
+ flush_slab
|
- discard_page
+ slab_to_discard
|
- page_to_unfreeze
+ slab_to_unfreeze
)
= E;

// convert most of struct page to struct slab usage inside functions (with
// exceptions), including specific variable renames
@@
identifier fn !~ "nearest_obj|obj_to_index|objs_per_slab_page|__slab_(un)*lock|__free_slab|free_nonslab_page|kmalloc_large_node";
expression E;
@@

 fn(...)
 {
<...
(
- int pages;
+ int slabs;
|
- int pages = E;
+ int slabs = E;
|
- page
+ slab
|
- flush_page
+ flush_slab
|
- partial_page
+ partial_slab
|
- oldpage->pages
+ oldslab->slabs
|
- oldpage
+ oldslab
|
- unsigned int nr_pages;
+ unsigned int nr_slabs;
|
- nr_pages
+ nr_slabs
|
- unsigned int partial_pages = E;
+ unsigned int partial_slabs = E;
|
- partial_pages
+ partial_slabs
)
...>
 }

// this has to be split out from the previous rule so that lines containing
// multiple matching changes will be fully converted
@@
identifier fn !~ "nearest_obj|obj_to_index|objs_per_slab_page|__slab_(un)*lock|__free_slab|free_nonslab_page|kmalloc_large_node";
@@

 fn(...)
 {
<...
(
- slab->pages
+ slab->slabs
|
- pages
+ slabs
|
- page2
+ slab2
|
- discard_page
+ slab_to_discard
|
- page_to_unfreeze
+ slab_to_unfreeze
)
...>
 }

// after we simply changed all occurences of page to slab, some usages need
// adjustment for slab-specific functions, or use slab_page() wrapper
@@
identifier fn !~ "nearest_obj|obj_to_index|objs_per_slab_page|__slab_(un)*lock|__free_slab|free_nonslab_page|kmalloc_large_node";
@@

 fn(...)
 {
<...
(
- page_slab(slab)
+ slab
|
- kasan_poison_slab(slab)
+ kasan_poison_slab(slab_page(slab))
|
- page_address(slab)
+ slab_address(slab)
|
- page_size(slab)
+ slab_size(slab)
|
- PageSlab(slab)
+ folio_test_slab(slab_folio(slab))
|
- page_to_nid(slab)
+ slab_nid(slab)
|
- compound_order(slab)
+ slab_order(slab)
)
...>
 }

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Julia Lawall <julia.lawall@inria.fr>
Cc: Luis Chamberlain <mcgrof@kernel.org>
2022-01-06 12:26:02 +01:00
Matthew Wilcox (Oracle) 01b34d1631 mm/slub: Convert pfmemalloc_match() to take a struct slab
Preparatory for mass conversion. Use the new slab_test_pfmemalloc()
helper.  As it doesn't do VM_BUG_ON(!PageSlab()) we no longer need the
pfmemalloc_match_unsafe() variant.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
2022-01-06 12:26:02 +01:00
Vlastimil Babka 4020b4a226 mm/slub: Convert __free_slab() to use struct slab
__free_slab() is on the boundary of distinguishing struct slab and
struct page so start with struct slab but convert to folio for working
with flags and folio_page() to call functions that require struct page.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
2022-01-06 12:26:01 +01:00
Vlastimil Babka 45387b8c14 mm/slub: Convert alloc_slab_page() to return a struct slab
Preparatory, callers convert back to struct page for now.

Also move setting page flags to alloc_slab_page() where we still operate
on a struct page. This means the page->slab_cache pointer is now set
later than the PageSlab flag, which could theoretically confuse some pfn
walker assuming PageSlab means there would be a valid cache pointer. But
as the code had no barriers and used __set_bit() anyway, it could have
happened already, so there shouldn't be such a walker.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
2022-01-06 12:26:01 +01:00
Matthew Wilcox (Oracle) fb012e278d mm/slub: Convert print_page_info() to print_slab_info()
Improve the type safety and prepare for further conversion. For flags
access, convert to folio internally.

[ vbabka@suse.cz: access flags via folio_flags() ]

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
2022-01-06 12:26:01 +01:00
Vlastimil Babka 0393895b09 mm/slub: Convert __slab_lock() and __slab_unlock() to struct slab
These functions operate on the PG_locked page flag, but make them accept
struct slab to encapsulate this implementation detail.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Roman Gushchin <guro@fb.com>
2022-01-06 12:26:01 +01:00
Matthew Wilcox (Oracle) d835eef4fc mm/slub: Convert kfree() to use a struct slab
Convert kfree(), kmem_cache_free() and ___cache_free() to resolve object
addresses to struct slab, using folio as intermediate step where needed.
Keep passing the result as struct page for now in preparation for mass
conversion of internal functions.

[ vbabka@suse.cz: Use folio as intermediate step when checking for
  large kmalloc pages, and when freeing them - rename
  free_nonslab_page() to free_large_kmalloc() that takes struct folio ]

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Roman Gushchin <guro@fb.com>
2022-01-06 12:25:57 +01:00
Matthew Wilcox (Oracle) cc465c3b23 mm/slub: Convert detached_freelist to use a struct slab
This gives us a little bit of extra typesafety as we know that nobody
called virt_to_page() instead of virt_to_head_page().

[ vbabka@suse.cz: Use folio as intermediate step when filtering out
  large kmalloc pages ]

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Roman Gushchin <guro@fb.com>
2022-01-06 12:25:51 +01:00
Matthew Wilcox (Oracle) 0b3eb091d5 mm: Convert check_heap_object() to use struct slab
Ensure that we're not seeing a tail page inside __check_heap_object() by
converting to a slab instead of a page.  Take the opportunity to mark
the slab as const since we're not modifying it.  Also move the
declaration of __check_heap_object() to mm/slab.h so it's not available
to the wider kernel.

[ vbabka@suse.cz: in check_heap_object() only convert to struct slab for
  actual PageSlab pages; use folio as intermediate step instead of page ]

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Roman Gushchin <guro@fb.com>
2022-01-06 12:25:51 +01:00
Matthew Wilcox (Oracle) 7213230af5 mm: Use struct slab in kmem_obj_info()
All three implementations of slab support kmem_obj_info() which reports
details of an object allocated from the slab allocator.  By using the
slab type instead of the page type, we make it obvious that this can
only be called for slabs.

[ vbabka@suse.cz: also convert the related kmem_valid_obj() to folios ]

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Roman Gushchin <guro@fb.com>
2022-01-06 12:25:51 +01:00
Matthew Wilcox (Oracle) 0c24811b12 mm: Convert __ksize() to struct slab
In SLUB, use folios, and struct slab to access slab_cache field.
In SLOB, use folios to properly resolve pointers beyond
PAGE_SIZE offset of the object.

[ vbabka@suse.cz: use folios, and only convert folio_test_slab() == true
  folios to struct slab ]

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Roman Gushchin <guro@fb.com>
2022-01-06 12:25:51 +01:00
Matthew Wilcox (Oracle) 82c1775dc1 mm: Convert virt_to_cache() to use struct slab
This function is entirely self-contained, so can be converted from page
to slab.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
2022-01-06 12:25:41 +01:00
Matthew Wilcox (Oracle) b918653b4f mm: Convert [un]account_slab_page() to struct slab
Convert the parameter of these functions to struct slab instead of
struct page and drop _page from the names. For now their callers just
convert page to slab.

[ vbabka@suse.cz: replace existing functions instead of calling them ]

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Roman Gushchin <guro@fb.com>
2022-01-06 12:25:40 +01:00
Matthew Wilcox (Oracle) d122019bf0 mm: Split slab into its own type
Make struct slab independent of struct page. It still uses the
underlying memory in struct page for storing slab-specific data, but
slab and slub can now be weaned off using struct page directly.  Some of
the wrapper functions (slab_address() and slab_order()) still need to
cast to struct folio, but this is a significant disentanglement.

[ vbabka@suse.cz: Rebase on folios, use folio instead of page where
  possible.

  Do not duplicate flags field in struct slab, instead make the related
  accessors go through slab_folio(). For testing pfmemalloc use the
  folio_*_active flag accessors directly so the PageSlabPfmemalloc
  wrappers can be removed later.

  Make folio_slab() expect only folio_test_slab() == true folios and
  virt_to_slab() return NULL when folio_test_slab() == false.

  Move struct slab to mm/slab.h.

  Don't represent with struct slab pages that are not true slab pages,
  but just a compound page obtained directly rom page allocator (with
  large kmalloc() for SLUB and SLOB). ]

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Roman Gushchin <guro@fb.com>
2022-01-06 12:25:40 +01:00
Vlastimil Babka ae16d059f8 mm/slub: Make object_err() static
There are no callers outside of mm/slub.c anymore.

Move freelist_corrupted() that calls object_err() to avoid a need for
forward declaration.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Roman Gushchin <guro@fb.com>
2022-01-06 12:25:40 +01:00
Vlastimil Babka c798154311 mm/slab: Dissolve slab_map_pages() in its caller
The function no longer does what its name and comment suggests, and just
sets two struct page fields, which can be done directly in its sole
caller.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
2022-01-06 12:25:25 +01:00
Mel Gorman 8008293888 mm: vmscan: reduce throttling due to a failure to make progress -fix
Hugh Dickins reported the following

	My tmpfs swapping load (tweaked to use huge pages more heavily
	than in real life) is far from being a realistic load: but it was
	notably slowed down by your throttling mods in 5.16-rc, and this
	patch makes it well again - thanks.

	But: it very quickly hit NULL pointer until I changed that last
	line to

        if (first_pgdat)
                consider_reclaim_throttle(first_pgdat, sc);

The likely issue is that huge pages are a major component of the test
workload.  When this is the case, first_pgdat may never get set if
compaction is ready to continue due to this check

        if (IS_ENABLED(CONFIG_COMPACTION) &&
            sc->order > PAGE_ALLOC_COSTLY_ORDER &&
            compaction_ready(zone, sc)) {
                sc->compaction_ready = true;
                continue;
        }

If this was true for every zone in the zonelist, first_pgdat would never
get set resulting in a NULL pointer exception.

Link: https://lkml.kernel.org/r/20211209095453.GM3366@techsingularity.net
Fixes: 1b4e3f26f9 ("mm: vmscan: Reduce throttling due to a failure to make progress")
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Reported-by: Hugh Dickins <hughd@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Rik van Riel <riel@surriel.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-12-31 13:12:55 -08:00
Mel Gorman 1b4e3f26f9 mm: vmscan: Reduce throttling due to a failure to make progress
Mike Galbraith, Alexey Avramov and Darrick Wong all reported similar
problems due to reclaim throttling for excessive lengths of time.  In
Alexey's case, a memory hog that should go OOM quickly stalls for
several minutes before stalling.  In Mike and Darrick's cases, a small
memcg environment stalled excessively even though the system had enough
memory overall.

Commit 69392a403f ("mm/vmscan: throttle reclaim when no progress is
being made") introduced the problem although commit a19594ca4a
("mm/vmscan: increase the timeout if page reclaim is not making
progress") made it worse.  Systems at or near an OOM state that cannot
be recovered must reach OOM quickly and memcg should kill tasks if a
memcg is near OOM.

To address this, only stall for the first zone in the zonelist, reduce
the timeout to 1 tick for VMSCAN_THROTTLE_NOPROGRESS and only stall if
the scan control nr_reclaimed is 0, kswapd is still active and there
were excessive pages pending for writeback.  If kswapd has stopped
reclaiming due to excessive failures, do not stall at all so that OOM
triggers relatively quickly.  Similarly, if an LRU is simply congested,
only lightly throttle similar to NOPROGRESS.

Alexey's original case was the most straight forward

	for i in {1..3}; do tail /dev/zero; done

On vanilla 5.16-rc1, this test stalled heavily, after the patch the test
completes in a few seconds similar to 5.15.

Alexey's second test case added watching a youtube video while tail runs
10 times.  On 5.15, playback only jitters slightly, 5.16-rc1 stalls a
lot with lots of frames missing and numerous audio glitches.  With this
patch applies, the video plays similarly to 5.15.

[lkp@intel.com: Fix W=1 build warning]

Link: https://lore.kernel.org/r/99e779783d6c7fce96448a3402061b9dc1b3b602.camel@gmx.de
Link: https://lore.kernel.org/r/20211124011954.7cab9bb4@mail.inbox.lv
Link: https://lore.kernel.org/r/20211022144651.19914-1-mgorman@techsingularity.net
Link: https://lore.kernel.org/r/20211202150614.22440-1-mgorman@techsingularity.net
Link: https://linux-regtracking.leemhuis.info/regzbot/regression/20211124011954.7cab9bb4@mail.inbox.lv/
Reported-and-tested-by: Alexey Avramov <hakavlad@inbox.lv>
Reported-and-tested-by: Mike Galbraith <efault@gmx.de>
Reported-and-tested-by: Darrick J. Wong <djwong@kernel.org>
Reported-by: kernel test robot <lkp@intel.com>
Acked-by: Hugh Dickins <hughd@google.com>
Tracked-by: Thorsten Leemhuis <regressions@leemhuis.info>
Fixes: 69392a403f ("mm/vmscan: throttle reclaim when no progress is being made")
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-12-31 11:17:07 -08:00
SeongJae Park ebb3f994dd mm/damon/dbgfs: fix 'struct pid' leaks in 'dbgfs_target_ids_write()'
DAMON debugfs interface increases the reference counts of 'struct pid's
for targets from the 'target_ids' file write callback
('dbgfs_target_ids_write()'), but decreases the counts only in DAMON
monitoring termination callback ('dbgfs_before_terminate()').

Therefore, when 'target_ids' file is repeatedly written without DAMON
monitoring start/termination, the reference count is not decreased and
therefore memory for the 'struct pid' cannot be freed.  This commit
fixes this issue by decreasing the reference counts when 'target_ids' is
written.

Link: https://lkml.kernel.org/r/20211229124029.23348-1-sj@kernel.org
Fixes: 4bc05954d0 ("mm/damon: implement a debugfs-based user space interface")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org>	[5.15+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-12-31 09:20:12 -08:00
Liu Shixin 2a57d83c78 mm/hwpoison: clear MF_COUNT_INCREASED before retrying get_any_page()
Hulk Robot reported a panic in put_page_testzero() when testing
madvise() with MADV_SOFT_OFFLINE.  The BUG() is triggered when retrying
get_any_page().  This is because we keep MF_COUNT_INCREASED flag in
second try but the refcnt is not increased.

    page dumped because: VM_BUG_ON_PAGE(page_ref_count(page) == 0)
    ------------[ cut here ]------------
    kernel BUG at include/linux/mm.h:737!
    invalid opcode: 0000 [#1] PREEMPT SMP
    CPU: 5 PID: 2135 Comm: sshd Tainted: G    B             5.16.0-rc6-dirty #373
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
    RIP: release_pages+0x53f/0x840
    Call Trace:
      free_pages_and_swap_cache+0x64/0x80
      tlb_flush_mmu+0x6f/0x220
      unmap_page_range+0xe6c/0x12c0
      unmap_single_vma+0x90/0x170
      unmap_vmas+0xc4/0x180
      exit_mmap+0xde/0x3a0
      mmput+0xa3/0x250
      do_exit+0x564/0x1470
      do_group_exit+0x3b/0x100
      __do_sys_exit_group+0x13/0x20
      __x64_sys_exit_group+0x16/0x20
      do_syscall_64+0x34/0x80
      entry_SYSCALL_64_after_hwframe+0x44/0xae
    Modules linked in:
    ---[ end trace e99579b570fe0649 ]---
    RIP: 0010:release_pages+0x53f/0x840

Link: https://lkml.kernel.org/r/20211221074908.3910286-1-liushixin2@huawei.com
Fixes: b94e02822d ("mm,hwpoison: try to narrow window race for free pages")
Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Reported-by: Hulk Robot <hulkci@huawei.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-12-25 12:20:56 -08:00
SeongJae Park 3479641796 mm/damon/dbgfs: protect targets destructions with kdamond_lock
DAMON debugfs interface iterates current monitoring targets in
'dbgfs_target_ids_read()' while holding the corresponding
'kdamond_lock'.  However, it also destructs the monitoring targets in
'dbgfs_before_terminate()' without holding the lock.  This can result in
a use_after_free bug.  This commit avoids the race by protecting the
destruction with the corresponding 'kdamond_lock'.

Link: https://lkml.kernel.org/r/20211221094447.2241-1-sj@kernel.org
Reported-by: Sangwoo Bae <sangwoob@amazon.com>
Fixes: 4bc05954d0 ("mm/damon: implement a debugfs-based user space interface")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org>	[5.15.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-12-25 12:20:56 -08:00
Naoya Horiguchi e37e7b0b3b mm, hwpoison: fix condition in free hugetlb page path
When a memory error hits a tail page of a free hugepage,
__page_handle_poison() is expected to be called to isolate the error in
4kB unit, but it's not called due to the outdated if-condition in
memory_failure_hugetlb().  This loses the chance to isolate the error in
the finer unit, so it's not optimal.  Drop the condition.

This "(p != head && TestSetPageHWPoison(head)" condition is based on the
old semantics of PageHWPoison on hugepage (where PG_hwpoison flag was
set on the subpage), so it's not necessray any more.  By getting to set
PG_hwpoison on head page for hugepages, concurrent error events on
different subpages in a single hugepage can be prevented by
TestSetPageHWPoison(head) at the beginning of memory_failure_hugetlb().
So dropping the condition should not reopen the race window originally
mentioned in commit b985194c8c ("hwpoison, hugetlb:
lock_page/unlock_page does not match for handling a free hugepage")

[naoya.horiguchi@linux.dev: fix "HardwareCorrupted" counter]
  Link: https://lkml.kernel.org/r/20211220084851.GA1460264@u2004

Link: https://lkml.kernel.org/r/20211210110208.879740-1-naoya.horiguchi@linux.dev
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reported-by: Fei Luo <luofei@unicloud.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: <stable@vger.kernel.org>	[5.14+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-12-25 12:20:55 -08:00
Andrey Ryabinin 3386353406 mm: mempolicy: fix THP allocations escaping mempolicy restrictions
alloc_pages_vma() may try to allocate THP page on the local NUMA node
first:

	page = __alloc_pages_node(hpage_node,
		gfp | __GFP_THISNODE | __GFP_NORETRY, order);

And if the allocation fails it retries allowing remote memory:

	if (!page && (gfp & __GFP_DIRECT_RECLAIM))
    		page = __alloc_pages_node(hpage_node,
					gfp, order);

However, this retry allocation completely ignores memory policy nodemask
allowing allocation to escape restrictions.

The first appearance of this bug seems to be the commit ac5b2c1891
("mm: thp: relax __GFP_THISNODE for MADV_HUGEPAGE mappings").

The bug disappeared later in the commit 89c83fb539 ("mm, thp:
consolidate THP gfp handling into alloc_hugepage_direct_gfpmask") and
reappeared again in slightly different form in the commit 76e654cc91
("mm, page_alloc: allow hugepage fallback to remote nodes when
madvised")

Fix this by passing correct nodemask to the __alloc_pages() call.

The demonstration/reproducer of the problem:

    $ mount -oremount,size=4G,huge=always /dev/shm/
    $ echo always > /sys/kernel/mm/transparent_hugepage/defrag
    $ cat mbind_thp.c
    #include <unistd.h>
    #include <sys/mman.h>
    #include <sys/stat.h>
    #include <fcntl.h>
    #include <assert.h>
    #include <stdlib.h>
    #include <stdio.h>
    #include <numaif.h>

    #define SIZE 2ULL << 30
    int main(int argc, char **argv)
    {
        int fd;
        unsigned long long i;
        char *addr;
        pid_t pid;
        char buf[100];
        unsigned long nodemask = 1;

        fd = open("/dev/shm/test", O_RDWR|O_CREAT);
        assert(fd > 0);
        assert(ftruncate(fd, SIZE) == 0);

        addr = mmap(NULL, SIZE, PROT_READ|PROT_WRITE,
                           MAP_SHARED, fd, 0);

        assert(mbind(addr, SIZE, MPOL_BIND, &nodemask, 2, MPOL_MF_STRICT|MPOL_MF_MOVE)==0);
        for (i = 0; i < SIZE; i+=4096) {
          addr[i] = 1;
        }
        pid = getpid();
        snprintf(buf, sizeof(buf), "grep shm /proc/%d/numa_maps", pid);
        system(buf);
        sleep(10000);

        return 0;
    }
    $ gcc mbind_thp.c -o mbind_thp -lnuma
    $ numactl -H
    available: 2 nodes (0-1)
    node 0 cpus: 0 2
    node 0 size: 1918 MB
    node 0 free: 1595 MB
    node 1 cpus: 1 3
    node 1 size: 2014 MB
    node 1 free: 1731 MB
    node distances:
    node   0   1
      0:  10  20
      1:  20  10
    $ rm -f /dev/shm/test; taskset -c 0 ./mbind_thp
    7fd970a00000 bind:0 file=/dev/shm/test dirty=524288 active=0 N0=396800 N1=127488 kernelpagesize_kB=4

Link: https://lkml.kernel.org/r/20211208165343.22349-1-arbn@yandex-team.com
Fixes: ac5b2c1891 ("mm: thp: relax __GFP_THISNODE for MADV_HUGEPAGE mappings")
Signed-off-by: Andrey Ryabinin <arbn@yandex-team.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Andrea Arcangeli <aarcange@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>
2021-12-25 12:20:55 -08:00
Baokun Li 0129ab1f26 kfence: fix memory leak when cat kfence objects
Hulk robot reported a kmemleak problem:

    unreferenced object 0xffff93d1d8cc02e8 (size 248):
      comm "cat", pid 23327, jiffies 4624670141 (age 495992.217s)
      hex dump (first 32 bytes):
        00 40 85 19 d4 93 ff ff 00 10 00 00 00 00 00 00  .@..............
        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
      backtrace:
         seq_open+0x2a/0x80
         full_proxy_open+0x167/0x1e0
         do_dentry_open+0x1e1/0x3a0
         path_openat+0x961/0xa20
         do_filp_open+0xae/0x120
         do_sys_openat2+0x216/0x2f0
         do_sys_open+0x57/0x80
         do_syscall_64+0x33/0x40
         entry_SYSCALL_64_after_hwframe+0x44/0xa9
    unreferenced object 0xffff93d419854000 (size 4096):
      comm "cat", pid 23327, jiffies 4624670141 (age 495992.217s)
      hex dump (first 32 bytes):
        6b 66 65 6e 63 65 2d 23 32 35 30 3a 20 30 78 30  kfence-#250: 0x0
        30 30 30 30 30 30 30 37 35 34 62 64 61 31 32 2d  0000000754bda12-
      backtrace:
         seq_read_iter+0x313/0x440
         seq_read+0x14b/0x1a0
         full_proxy_read+0x56/0x80
         vfs_read+0xa5/0x1b0
         ksys_read+0xa0/0xf0
         do_syscall_64+0x33/0x40
         entry_SYSCALL_64_after_hwframe+0x44/0xa9

I find that we can easily reproduce this problem with the following
commands:

	cat /sys/kernel/debug/kfence/objects
	echo scan > /sys/kernel/debug/kmemleak
	cat /sys/kernel/debug/kmemleak

The leaked memory is allocated in the stack below:

    do_syscall_64
      do_sys_open
        do_dentry_open
          full_proxy_open
            seq_open            ---> alloc seq_file
      vfs_read
        full_proxy_read
          seq_read
            seq_read_iter
              traverse          ---> alloc seq_buf

And it should have been released in the following process:

    do_syscall_64
      syscall_exit_to_user_mode
        exit_to_user_mode_prepare
          task_work_run
            ____fput
              __fput
                full_proxy_release  ---> free here

However, the release function corresponding to file_operations is not
implemented in kfence.  As a result, a memory leak occurs.  Therefore,
the solution to this problem is to implement the corresponding release
function.

Link: https://lkml.kernel.org/r/20211206133628.2822545-1-libaokun1@huawei.com
Fixes: 0ce20dd840 ("mm: add Kernel Electric-Fence infrastructure")
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reported-by: Hulk Robot <hulkci@huawei.com>
Acked-by: Marco Elver <elver@google.com>
Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-12-25 12:20:55 -08:00
Linus Torvalds 8f97a35a53 Merge branch 'for-5.16-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu
Pull percpu fixes from Dennis Zhou:
 "This contains a fix for SMP && !MMU archs for percpu which has been
  tested by arm and sh. It seems in the past they have gotten away with
  it due to mapping of vm functions to km functions, but this fell apart
  a few releases ago and was just reported recently.

  The other is just a minor dependency clean up.

  I think queued up right now by Andrew is a fix in percpu that papers
  of what seems to be a bug in hotplug for a special situation with
  memoryless nodes. Michal Hocko is digging into it further"

* 'for-5.16-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu:
  percpu_ref: Replace kernel.h with the necessary inclusions
  percpu: km: ensure it is used with NOMMU (either UP or SMP)
2021-12-11 16:14:17 -08:00
Manjong Lee 3c376dfafb mm: bdi: initialize bdi_min_ratio when bdi is unregistered
Initialize min_ratio if it is set during bdi unregistration.  This can
prevent problems that may occur a when bdi is removed without resetting
min_ratio.

For example.
1) insert external sdcard
2) set external sdcard's min_ratio 70
3) remove external sdcard without setting min_ratio 0
4) insert external sdcard
5) set external sdcard's min_ratio 70 << error occur(can't set)

Because when an sdcard is removed, the present bdi_min_ratio value will
remain.  Currently, the only way to reset bdi_min_ratio is to reboot.

[akpm@linux-foundation.org: tweak comment and coding style]

Link: https://lkml.kernel.org/r/20211021161942.5983-1-mj0123.lee@samsung.com
Signed-off-by: Manjong Lee <mj0123.lee@samsung.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Changheun Lee <nanich.lee@samsung.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: <seunghwan.hyun@samsung.com>
Cc: <sookwan7.kim@samsung.com>
Cc: <yt0928.kim@samsung.com>
Cc: <junho89.kim@samsung.com>
Cc: <jisoo2146.oh@samsung.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-12-10 17:10:56 -08:00
Zhenguo Yao 4178158ef8 hugetlbfs: fix issue of preallocation of gigantic pages can't work
Preallocation of gigantic pages can't work bacause of commit
b5389086ad ("hugetlbfs: extend the definition of hugepages parameter
to support node allocation").  When nid is NUMA_NO_NODE(-1),
alloc_bootmem_huge_page will always return without doing allocation.
Fix this by adding more check.

Link: https://lkml.kernel.org/r/20211129133803.15653-1-yaozhenguo1@gmail.com
Fixes: b5389086ad ("hugetlbfs: extend the definition of hugepages parameter to support node allocation")
Signed-off-by: Zhenguo Yao <yaozhenguo1@gmail.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Tested-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-12-10 17:10:56 -08:00
Waiman Long a7ebf564de mm/memcg: relocate mod_objcg_mlstate(), get_obj_stock() and put_obj_stock()
All the calls to mod_objcg_mlstate(), get_obj_stock() and
put_obj_stock() are done by functions defined within the same "#ifdef
CONFIG_MEMCG_KMEM" compilation block.  When CONFIG_MEMCG_KMEM isn't
defined, the following compilation warnings will be issued [1] and [2].

  mm/memcontrol.c:785:20: warning: unused function 'mod_objcg_mlstate'
  mm/memcontrol.c:2113:33: warning: unused function 'get_obj_stock'

Fix these warning by moving those functions to under the same
CONFIG_MEMCG_KMEM compilation block.  There is no functional change.

[1] https://lore.kernel.org/lkml/202111272014.WOYNLUV6-lkp@intel.com/
[2] https://lore.kernel.org/lkml/202111280551.LXsWYt1T-lkp@intel.com/

Link: https://lkml.kernel.org/r/20211129161140.306488-1-longman@redhat.com
Fixes: 559271146e ("mm/memcg: optimize user context object stock access")
Fixes: 68ac5b3c8d ("mm/memcg: cache vmstat data in percpu memcg_stock_pcp")
Signed-off-by: Waiman Long <longman@redhat.com>
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.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>
2021-12-10 17:10:56 -08:00
Gerald Schaefer 005a79e5c2 mm/slub: fix endianness bug for alloc/free_traces attributes
On big-endian s390, the alloc/free_traces attributes produce endless
output, because of always 0 idx in slab_debugfs_show().

idx is de-referenced from *v, which points to a loff_t value, with

    unsigned int idx = *(unsigned int *)v;

This will only give the upper 32 bits on big-endian, which remain 0.

Instead of only fixing this de-reference, during discussion it seemed
more appropriate to change the seq_ops so that they use an explicit
iterator in private loc_track struct.

This patch adds idx to loc_track, which will also fix the endianness
bug.

Link: https://lore.kernel.org/r/20211117193932.4049412-1-gerald.schaefer@linux.ibm.com
Link: https://lkml.kernel.org/r/20211126171848.17534-1-gerald.schaefer@linux.ibm.com
Fixes: 64dd68497b ("mm: slub: move sysfs slab alloc/free interfaces to debugfs")
Signed-off-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Reported-by: Steffen Maier <maier@linux.ibm.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Faiyaz Mohammed <faiyazm@codeaurora.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-12-10 17:10:56 -08:00
SeongJae Park 9f86d62429 mm/damon/vaddr-test: remove unnecessary variables
A couple of test functions in DAMON virtual address space monitoring
primitives implementation has unnecessary damon_ctx variables.  This
commit removes those.

Link: https://lkml.kernel.org/r/20211201150440.1088-7-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Brendan Higgins <brendanhiggins@google.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>
2021-12-10 17:10:56 -08:00
SeongJae Park 044cd9750f mm/damon/vaddr-test: split a test function having >1024 bytes frame size
On some configuration[1], 'damon_test_split_evenly()' kunit test
function has >1024 bytes frame size, so below build warning is
triggered:

      CC      mm/damon/vaddr.o
    In file included from mm/damon/vaddr.c:672:
    mm/damon/vaddr-test.h: In function 'damon_test_split_evenly':
    mm/damon/vaddr-test.h:309:1: warning: the frame size of 1064 bytes is larger than 1024 bytes [-Wframe-larger-than=]
      309 | }
          | ^

This commit fixes the warning by separating the common logic in the
function.

[1] https://lore.kernel.org/linux-mm/202111182146.OV3C4uGr-lkp@intel.com/

Link: https://lkml.kernel.org/r/20211201150440.1088-6-sj@kernel.org
Fixes: 17ccae8bb5 ("mm/damon: add kunit tests")
Signed-off-by: SeongJae Park <sj@kernel.org>
Reported-by: kernel test robot <lkp@intel.com>
Cc: Brendan Higgins <brendanhiggins@google.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>
2021-12-10 17:10:56 -08:00
SeongJae Park 09e12289cc mm/damon/vaddr: remove an unnecessary warning message
The DAMON virtual address space monitoring primitive prints a warning
message for wrong DAMOS action.  However, it is not essential as the
code returns appropriate failure in the case.  This commit removes the
message to make the log clean.

Link: https://lkml.kernel.org/r/20211201150440.1088-5-sj@kernel.org
Fixes: 6dea8add4d ("mm/damon/vaddr: support DAMON-based Operation Schemes")
Signed-off-by: SeongJae Park <sj@kernel.org>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Brendan Higgins <brendanhiggins@google.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>
2021-12-10 17:10:56 -08:00