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22 hotfixes. 11 are cc:stable and the remainder address post-6.7 issues

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or aren't considered appropriate for backporting.
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Merge tag 'mm-hotfixes-stable-2024-01-28-23-21' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc fixes from Andrew Morton:
 "22 hotfixes. 11 are cc:stable and the remainder address post-6.7
  issues or aren't considered appropriate for backporting"

* tag 'mm-hotfixes-stable-2024-01-28-23-21' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (22 commits)
  mm: thp_get_unmapped_area must honour topdown preference
  mm: huge_memory: don't force huge page alignment on 32 bit
  userfaultfd: fix mmap_changing checking in mfill_atomic_hugetlb
  selftests/mm: ksm_tests should only MADV_HUGEPAGE valid memory
  scs: add CONFIG_MMU dependency for vfree_atomic()
  mm/memory: fix folio_set_dirty() vs. folio_mark_dirty() in zap_pte_range()
  mm/huge_memory: fix folio_set_dirty() vs. folio_mark_dirty()
  selftests/mm: Update va_high_addr_switch.sh to check CPU for la57 flag
  selftests: mm: fix map_hugetlb failure on 64K page size systems
  MAINTAINERS: supplement of zswap maintainers update
  stackdepot: make fast paths lock-less again
  stackdepot: add stats counters exported via debugfs
  mm, kmsan: fix infinite recursion due to RCU critical section
  mm/writeback: fix possible divide-by-zero in wb_dirty_limits(), again
  selftests/mm: switch to bash from sh
  MAINTAINERS: add man-pages git trees
  mm: memcontrol: don't throttle dying tasks on memory.high
  mm: mmap: map MAP_STACK to VM_NOHUGEPAGE
  uprobes: use pagesize-aligned virtual address when replacing pages
  selftests/mm: mremap_test: fix build warning
  ...
This commit is contained in:
Linus Torvalds 2024-01-29 17:12:16 -08:00
commit 6f3d7d5ced
23 changed files with 394 additions and 156 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
CREDITS
View File

@ -2161,6 +2161,19 @@ N: Mike Kravetz
E: mike.kravetz@oracle.com
D: Maintenance and development of the hugetlb subsystem
N: Seth Jennings
E: sjenning@redhat.com
D: Creation and maintenance of zswap
N: Dan Streetman
E: ddstreet@ieee.org
D: Maintenance and development of zswap
D: Creation and maintenance of the zpool API
N: Vitaly Wool
E: vitaly.wool@konsulko.com
D: Maintenance and development of zswap
N: Andreas S. Krebs
E: akrebs@altavista.net
D: CYPRESS CY82C693 chipset IDE, Digital's PC-Alpha 164SX boards

11
MAINTAINERS
View File

@ -12903,6 +12903,8 @@ M: Alejandro Colomar <alx@kernel.org>
L: linux-man@vger.kernel.org
S: Maintained
W: http://www.kernel.org/doc/man-pages
T: git git://git.kernel.org/pub/scm/docs/man-pages/man-pages.git
T: git git://www.alejandro-colomar.es/src/alx/linux/man-pages/man-pages.git
MANAGEMENT COMPONENT TRANSPORT PROTOCOL (MCTP)
M: Jeremy Kerr <jk@codeconstruct.com.au>
@ -24341,13 +24343,6 @@ T: git git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/zonefs.git
F: Documentation/filesystems/zonefs.rst
F: fs/zonefs/
ZPOOL COMPRESSED PAGE STORAGE API
M: Dan Streetman <ddstreet@ieee.org>
L: linux-mm@kvack.org
S: Maintained
F: include/linux/zpool.h
F: mm/zpool.c
ZR36067 VIDEO FOR LINUX DRIVER
M: Corentin Labbe <clabbe@baylibre.com>
L: mjpeg-users@lists.sourceforge.net
@ -24399,7 +24394,9 @@ M: Nhat Pham <nphamcs@gmail.com>
L: linux-mm@kvack.org
S: Maintained
F: Documentation/admin-guide/mm/zswap.rst
F: include/linux/zpool.h
F: include/linux/zswap.h
F: mm/zpool.c
F: mm/zswap.c
THE REST

1
arch/Kconfig
View File

@ -673,6 +673,7 @@ config SHADOW_CALL_STACK
bool "Shadow Call Stack"
depends on ARCH_SUPPORTS_SHADOW_CALL_STACK
depends on DYNAMIC_FTRACE_WITH_ARGS || DYNAMIC_FTRACE_WITH_REGS || !FUNCTION_GRAPH_TRACER
depends on MMU
help
This option enables the compiler's Shadow Call Stack, which
uses a shadow stack to protect function return addresses from

17
arch/x86/include/asm/kmsan.h
View File

@ -64,6 +64,7 @@ static inline bool kmsan_virt_addr_valid(void *addr)
{
unsigned long x = (unsigned long)addr;
unsigned long y = x - __START_KERNEL_map;
bool ret;
/* use the carry flag to determine if x was < __START_KERNEL_map */
if (unlikely(x > y)) {
@ -79,7 +80,21 @@ static inline bool kmsan_virt_addr_valid(void *addr)
return false;
}
return pfn_valid(x >> PAGE_SHIFT);
/*
* pfn_valid() relies on RCU, and may call into the scheduler on exiting
* the critical section. However, this would result in recursion with
* KMSAN. Therefore, disable preemption here, and re-enable preemption
* below while suppressing reschedules to avoid recursion.
*
* Note, this sacrifices occasionally breaking scheduling guarantees.
* Although, a kernel compiled with KMSAN has already given up on any
* performance guarantees due to being heavily instrumented.
*/
preempt_disable();
ret = pfn_valid(x >> PAGE_SHIFT);
preempt_enable_no_resched();
return ret;
}
#endif /* !MODULE */

2
fs/hugetlbfs/inode.c
View File

@ -340,7 +340,7 @@ static ssize_t hugetlbfs_read_iter(struct kiocb *iocb, struct iov_iter *to)
} else {
folio_unlock(folio);
if (!folio_test_has_hwpoisoned(folio))
if (!folio_test_hwpoison(folio))
want = nr;
else {
/*

1
include/linux/mman.h
View File

@ -156,6 +156,7 @@ calc_vm_flag_bits(unsigned long flags)
return _calc_vm_trans(flags, MAP_GROWSDOWN, VM_GROWSDOWN ) |
_calc_vm_trans(flags, MAP_LOCKED, VM_LOCKED ) |
_calc_vm_trans(flags, MAP_SYNC, VM_SYNC ) |
_calc_vm_trans(flags, MAP_STACK, VM_NOHUGEPAGE) |
arch_calc_vm_flag_bits(flags);
}

6
include/linux/mmzone.h
View File

@ -2013,9 +2013,9 @@ static inline int pfn_valid(unsigned long pfn)
if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
return 0;
ms = __pfn_to_section(pfn);
rcu_read_lock();
rcu_read_lock_sched();
if (!valid_section(ms)) {
rcu_read_unlock();
rcu_read_unlock_sched();
return 0;
}
/*
@ -2023,7 +2023,7 @@ static inline int pfn_valid(unsigned long pfn)
* the entire section-sized span.
*/
ret = early_section(ms) || pfn_section_valid(ms, pfn);
rcu_read_unlock();
rcu_read_unlock_sched();
return ret;
}

2
kernel/events/uprobes.c
View File

@ -537,7 +537,7 @@ retry:
}
}
ret = __replace_page(vma, vaddr, old_page, new_page);
ret = __replace_page(vma, vaddr & PAGE_MASK, old_page, new_page);
if (new_page)
put_page(new_page);
put_old:

373
lib/stackdepot.c
View File

@ -14,6 +14,7 @@
#define pr_fmt(fmt) "stackdepot: " fmt
#include <linux/debugfs.h>
#include <linux/gfp.h>
#include <linux/jhash.h>
#include <linux/kernel.h>
@ -21,8 +22,9 @@
#include <linux/list.h>
#include <linux/mm.h>
#include <linux/mutex.h>
#include <linux/percpu.h>
#include <linux/printk.h>
#include <linux/rculist.h>
#include <linux/rcupdate.h>
#include <linux/refcount.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
@ -67,12 +69,28 @@ union handle_parts {
};
struct stack_record {
struct list_head list; /* Links in hash table or freelist */
struct list_head hash_list; /* Links in the hash table */
u32 hash; /* Hash in hash table */
u32 size; /* Number of stored frames */
union handle_parts handle;
union handle_parts handle; /* Constant after initialization */
refcount_t count;
unsigned long entries[CONFIG_STACKDEPOT_MAX_FRAMES]; /* Frames */
union {
unsigned long entries[CONFIG_STACKDEPOT_MAX_FRAMES]; /* Frames */
struct {
/*
* An important invariant of the implementation is to
* only place a stack record onto the freelist iff its
* refcount is zero. Because stack records with a zero
* refcount are never considered as valid, it is safe to
* union @entries and freelist management state below.
* Conversely, as soon as an entry is off the freelist
* and its refcount becomes non-zero, the below must not
* be accessed until being placed back on the freelist.
*/
struct list_head free_list; /* Links in the freelist */
unsigned long rcu_state; /* RCU cookie */
};
};
};
#define DEPOT_STACK_RECORD_SIZE \
@ -112,8 +130,25 @@ static LIST_HEAD(free_stacks);
* yet allocated or if the limit on the number of pools is reached.
*/
static bool new_pool_required = true;
/* Lock that protects the variables above. */
static DEFINE_RWLOCK(pool_rwlock);
/* The lock must be held when performing pool or freelist modifications. */
static DEFINE_RAW_SPINLOCK(pool_lock);
/* Statistics counters for debugfs. */
enum depot_counter_id {
DEPOT_COUNTER_ALLOCS,
DEPOT_COUNTER_FREES,
DEPOT_COUNTER_INUSE,
DEPOT_COUNTER_FREELIST_SIZE,
DEPOT_COUNTER_COUNT,
};
static long counters[DEPOT_COUNTER_COUNT];
static const char *const counter_names[] = {
[DEPOT_COUNTER_ALLOCS] = "allocations",
[DEPOT_COUNTER_FREES] = "frees",
[DEPOT_COUNTER_INUSE] = "in_use",
[DEPOT_COUNTER_FREELIST_SIZE] = "freelist_size",
};
static_assert(ARRAY_SIZE(counter_names) == DEPOT_COUNTER_COUNT);
static int __init disable_stack_depot(char *str)
{
@ -258,14 +293,15 @@ out_unlock:
}
EXPORT_SYMBOL_GPL(stack_depot_init);
/* Initializes a stack depol pool. */
/*
* Initializes new stack depot @pool, release all its entries to the freelist,
* and update the list of pools.
*/
static void depot_init_pool(void *pool)
{
int offset;
lockdep_assert_held_write(&pool_rwlock);
WARN_ON(!list_empty(&free_stacks));
lockdep_assert_held(&pool_lock);
/* Initialize handles and link stack records into the freelist. */
for (offset = 0; offset <= DEPOT_POOL_SIZE - DEPOT_STACK_RECORD_SIZE;
@ -276,18 +312,36 @@ static void depot_init_pool(void *pool)
stack->handle.offset = offset >> DEPOT_STACK_ALIGN;
stack->handle.extra = 0;
list_add(&stack->list, &free_stacks);
/*
* Stack traces of size 0 are never saved, and we can simply use
* the size field as an indicator if this is a new unused stack
* record in the freelist.
*/
stack->size = 0;
INIT_LIST_HEAD(&stack->hash_list);
/*
* Add to the freelist front to prioritize never-used entries:
* required in case there are entries in the freelist, but their
* RCU cookie still belongs to the current RCU grace period
* (there can still be concurrent readers).
*/
list_add(&stack->free_list, &free_stacks);
counters[DEPOT_COUNTER_FREELIST_SIZE]++;
}
/* Save reference to the pool to be used by depot_fetch_stack(). */
stack_pools[pools_num] = pool;
pools_num++;
/* Pairs with concurrent READ_ONCE() in depot_fetch_stack(). */
WRITE_ONCE(pools_num, pools_num + 1);
ASSERT_EXCLUSIVE_WRITER(pools_num);
}
/* Keeps the preallocated memory to be used for a new stack depot pool. */
static void depot_keep_new_pool(void **prealloc)
{
lockdep_assert_held_write(&pool_rwlock);
lockdep_assert_held(&pool_lock);
/*
* If a new pool is already saved or the maximum number of
@ -310,17 +364,16 @@ static void depot_keep_new_pool(void **prealloc)
* number of pools is reached. In either case, take note that
* keeping another pool is not required.
*/
new_pool_required = false;
WRITE_ONCE(new_pool_required, false);
}
/* Updates references to the current and the next stack depot pools. */
static bool depot_update_pools(void **prealloc)
/*
* Try to initialize a new stack depot pool from either a previous or the
* current pre-allocation, and release all its entries to the freelist.
*/
static bool depot_try_init_pool(void **prealloc)
{
lockdep_assert_held_write(&pool_rwlock);
/* Check if we still have objects in the freelist. */
if (!list_empty(&free_stacks))
goto out_keep_prealloc;
lockdep_assert_held(&pool_lock);
/* Check if we have a new pool saved and use it. */
if (new_pool) {
@ -329,10 +382,9 @@ static bool depot_update_pools(void **prealloc)
/* Take note that we might need a new new_pool. */
if (pools_num < DEPOT_MAX_POOLS)
new_pool_required = true;
WRITE_ONCE(new_pool_required, true);
/* Try keeping the preallocated memory for new_pool. */
goto out_keep_prealloc;
return true;
}
/* Bail out if we reached the pool limit. */
@ -349,12 +401,32 @@ static bool depot_update_pools(void **prealloc)
}
return false;
}
out_keep_prealloc:
/* Keep the preallocated memory for a new pool if required. */
if (*prealloc)
depot_keep_new_pool(prealloc);
return true;
/* Try to find next free usable entry. */
static struct stack_record *depot_pop_free(void)
{
struct stack_record *stack;
lockdep_assert_held(&pool_lock);
if (list_empty(&free_stacks))
return NULL;
/*
* We maintain the invariant that the elements in front are least
* recently used, and are therefore more likely to be associated with an
* RCU grace period in the past. Consequently it is sufficient to only
* check the first entry.
*/
stack = list_first_entry(&free_stacks, struct stack_record, free_list);
if (stack->size && !poll_state_synchronize_rcu(stack->rcu_state))
return NULL;
list_del(&stack->free_list);
counters[DEPOT_COUNTER_FREELIST_SIZE]--;
return stack;
}
/* Allocates a new stack in a stack depot pool. */
@ -363,19 +435,22 @@ depot_alloc_stack(unsigned long *entries, int size, u32 hash, void **prealloc)
{
struct stack_record *stack;
lockdep_assert_held_write(&pool_rwlock);
lockdep_assert_held(&pool_lock);
/* Update current and new pools if required and possible. */
if (!depot_update_pools(prealloc))
/* This should already be checked by public API entry points. */
if (WARN_ON_ONCE(!size))
return NULL;
/* Check if we have a stack record to save the stack trace. */
if (list_empty(&free_stacks))
return NULL;
/* Get and unlink the first entry from the freelist. */
stack = list_first_entry(&free_stacks, struct stack_record, list);
list_del(&stack->list);
stack = depot_pop_free();
if (!stack) {
/* No usable entries on the freelist - try to refill the freelist. */
if (!depot_try_init_pool(prealloc))
return NULL;
stack = depot_pop_free();
if (WARN_ON(!stack))
return NULL;
}
/* Limit number of saved frames to CONFIG_STACKDEPOT_MAX_FRAMES. */
if (size > CONFIG_STACKDEPOT_MAX_FRAMES)
@ -394,38 +469,80 @@ depot_alloc_stack(unsigned long *entries, int size, u32 hash, void **prealloc)
*/
kmsan_unpoison_memory(stack, DEPOT_STACK_RECORD_SIZE);
counters[DEPOT_COUNTER_ALLOCS]++;
counters[DEPOT_COUNTER_INUSE]++;
return stack;
}
static struct stack_record *depot_fetch_stack(depot_stack_handle_t handle)
{
const int pools_num_cached = READ_ONCE(pools_num);
union handle_parts parts = { .handle = handle };
void *pool;
size_t offset = parts.offset << DEPOT_STACK_ALIGN;
struct stack_record *stack;
lockdep_assert_held(&pool_rwlock);
lockdep_assert_not_held(&pool_lock);
if (parts.pool_index > pools_num) {
if (parts.pool_index > pools_num_cached) {
WARN(1, "pool index %d out of bounds (%d) for stack id %08x\n",
parts.pool_index, pools_num, handle);
parts.pool_index, pools_num_cached, handle);
return NULL;
}
pool = stack_pools[parts.pool_index];
if (!pool)
if (WARN_ON(!pool))
return NULL;
stack = pool + offset;
if (WARN_ON(!refcount_read(&stack->count)))
return NULL;
return stack;
}
/* Links stack into the freelist. */
static void depot_free_stack(struct stack_record *stack)
{
lockdep_assert_held_write(&pool_rwlock);
unsigned long flags;
list_add(&stack->list, &free_stacks);
lockdep_assert_not_held(&pool_lock);
raw_spin_lock_irqsave(&pool_lock, flags);
printk_deferred_enter();
/*
* Remove the entry from the hash list. Concurrent list traversal may
* still observe the entry, but since the refcount is zero, this entry
* will no longer be considered as valid.
*/
list_del_rcu(&stack->hash_list);
/*
* Due to being used from constrained contexts such as the allocators,
* NMI, or even RCU itself, stack depot cannot rely on primitives that
* would sleep (such as synchronize_rcu()) or recursively call into
* stack depot again (such as call_rcu()).
*
* Instead, get an RCU cookie, so that we can ensure this entry isn't
* moved onto another list until the next grace period, and concurrent
* RCU list traversal remains safe.
*/
stack->rcu_state = get_state_synchronize_rcu();
/*
* Add the entry to the freelist tail, so that older entries are
* considered first - their RCU cookie is more likely to no longer be
* associated with the current grace period.
*/
list_add_tail(&stack->free_list, &free_stacks);
counters[DEPOT_COUNTER_FREELIST_SIZE]++;
counters[DEPOT_COUNTER_FREES]++;
counters[DEPOT_COUNTER_INUSE]--;
printk_deferred_exit();
raw_spin_unlock_irqrestore(&pool_lock, flags);
}
/* Calculates the hash for a stack. */
@ -453,22 +570,52 @@ int stackdepot_memcmp(const unsigned long *u1, const unsigned long *u2,
/* Finds a stack in a bucket of the hash table. */
static inline struct stack_record *find_stack(struct list_head *bucket,
unsigned long *entries, int size,
u32 hash)
unsigned long *entries, int size,
u32 hash, depot_flags_t flags)
{
struct list_head *pos;
struct stack_record *found;
struct stack_record *stack, *ret = NULL;
lockdep_assert_held(&pool_rwlock);
/*
* Stack depot may be used from instrumentation that instruments RCU or
* tracing itself; use variant that does not call into RCU and cannot be
* traced.
*
* Note: Such use cases must take care when using refcounting to evict
* unused entries, because the stack record free-then-reuse code paths
* do call into RCU.
*/
rcu_read_lock_sched_notrace();
list_for_each(pos, bucket) {
found = list_entry(pos, struct stack_record, list);
if (found->hash == hash &&
found->size == size &&
!stackdepot_memcmp(entries, found->entries, size))
return found;
list_for_each_entry_rcu(stack, bucket, hash_list) {
if (stack->hash != hash || stack->size != size)
continue;
/*
* This may race with depot_free_stack() accessing the freelist
* management state unioned with @entries. The refcount is zero
* in that case and the below refcount_inc_not_zero() will fail.
*/
if (data_race(stackdepot_memcmp(entries, stack->entries, size)))
continue;
/*
* Try to increment refcount. If this succeeds, the stack record
* is valid and has not yet been freed.
*
* If STACK_DEPOT_FLAG_GET is not used, it is undefined behavior
* to then call stack_depot_put() later, and we can assume that
* a stack record is never placed back on the freelist.
*/
if ((flags & STACK_DEPOT_FLAG_GET) && !refcount_inc_not_zero(&stack->count))
continue;
ret = stack;
break;
}
return NULL;
rcu_read_unlock_sched_notrace();
return ret;
}
depot_stack_handle_t stack_depot_save_flags(unsigned long *entries,
@ -482,7 +629,6 @@ depot_stack_handle_t stack_depot_save_flags(unsigned long *entries,
struct page *page = NULL;
void *prealloc = NULL;
bool can_alloc = depot_flags & STACK_DEPOT_FLAG_CAN_ALLOC;
bool need_alloc = false;
unsigned long flags;
u32 hash;
@ -505,31 +651,16 @@ depot_stack_handle_t stack_depot_save_flags(unsigned long *entries,
hash = hash_stack(entries, nr_entries);
bucket = &stack_table[hash & stack_hash_mask];
read_lock_irqsave(&pool_rwlock, flags);
printk_deferred_enter();
/* Fast path: look the stack trace up without full locking. */
found = find_stack(bucket, entries, nr_entries, hash);
if (found) {
if (depot_flags & STACK_DEPOT_FLAG_GET)
refcount_inc(&found->count);
printk_deferred_exit();
read_unlock_irqrestore(&pool_rwlock, flags);
/* Fast path: look the stack trace up without locking. */
found = find_stack(bucket, entries, nr_entries, hash, depot_flags);
if (found)
goto exit;
}
/* Take note if another stack pool needs to be allocated. */
if (new_pool_required)
need_alloc = true;
printk_deferred_exit();
read_unlock_irqrestore(&pool_rwlock, flags);
/*
* Allocate memory for a new pool if required now:
* we won't be able to do that under the lock.
*/
if (unlikely(can_alloc && need_alloc)) {
if (unlikely(can_alloc && READ_ONCE(new_pool_required))) {
/*
* Zero out zone modifiers, as we don't have specific zone
* requirements. Keep the flags related to allocation in atomic
@ -543,31 +674,36 @@ depot_stack_handle_t stack_depot_save_flags(unsigned long *entries,
prealloc = page_address(page);
}
write_lock_irqsave(&pool_rwlock, flags);
raw_spin_lock_irqsave(&pool_lock, flags);
printk_deferred_enter();
found = find_stack(bucket, entries, nr_entries, hash);
/* Try to find again, to avoid concurrently inserting duplicates. */
found = find_stack(bucket, entries, nr_entries, hash, depot_flags);
if (!found) {
struct stack_record *new =
depot_alloc_stack(entries, nr_entries, hash, &prealloc);
if (new) {
list_add(&new->list, bucket);
/*
* This releases the stack record into the bucket and
* makes it visible to readers in find_stack().
*/
list_add_rcu(&new->hash_list, bucket);
found = new;
}
} else {
if (depot_flags & STACK_DEPOT_FLAG_GET)
refcount_inc(&found->count);
}
if (prealloc) {
/*
* Stack depot already contains this stack trace, but let's
* keep the preallocated memory for future.
* Either stack depot already contains this stack trace, or
* depot_alloc_stack() did not consume the preallocated memory.
* Try to keep the preallocated memory for future.
*/
if (prealloc)
depot_keep_new_pool(&prealloc);
depot_keep_new_pool(&prealloc);
}
printk_deferred_exit();
write_unlock_irqrestore(&pool_rwlock, flags);
raw_spin_unlock_irqrestore(&pool_lock, flags);
exit:
if (prealloc) {
/* Stack depot didn't use this memory, free it. */
@ -592,7 +728,6 @@ unsigned int stack_depot_fetch(depot_stack_handle_t handle,
unsigned long **entries)
{
struct stack_record *stack;
unsigned long flags;
*entries = NULL;
/*
@ -604,13 +739,13 @@ unsigned int stack_depot_fetch(depot_stack_handle_t handle,
if (!handle || stack_depot_disabled)
return 0;
read_lock_irqsave(&pool_rwlock, flags);
printk_deferred_enter();
stack = depot_fetch_stack(handle);
printk_deferred_exit();
read_unlock_irqrestore(&pool_rwlock, flags);
/*
* Should never be NULL, otherwise this is a use-after-put (or just a
* corrupt handle).
*/
if (WARN(!stack, "corrupt handle or use after stack_depot_put()"))
return 0;
*entries = stack->entries;
return stack->size;
@ -620,29 +755,20 @@ EXPORT_SYMBOL_GPL(stack_depot_fetch);
void stack_depot_put(depot_stack_handle_t handle)
{
struct stack_record *stack;
unsigned long flags;
if (!handle || stack_depot_disabled)
return;
write_lock_irqsave(&pool_rwlock, flags);
printk_deferred_enter();
stack = depot_fetch_stack(handle);
if (WARN_ON(!stack))
goto out;
/*
* Should always be able to find the stack record, otherwise this is an
* unbalanced put attempt (or corrupt handle).
*/
if (WARN(!stack, "corrupt handle or unbalanced stack_depot_put()"))
return;
if (refcount_dec_and_test(&stack->count)) {
/* Unlink stack from the hash table. */
list_del(&stack->list);
/* Free stack. */
if (refcount_dec_and_test(&stack->count))
depot_free_stack(stack);
}
out:
printk_deferred_exit();
write_unlock_irqrestore(&pool_rwlock, flags);
}
EXPORT_SYMBOL_GPL(stack_depot_put);
@ -690,3 +816,30 @@ unsigned int stack_depot_get_extra_bits(depot_stack_handle_t handle)
return parts.extra;
}
EXPORT_SYMBOL(stack_depot_get_extra_bits);
static int stats_show(struct seq_file *seq, void *v)
{
/*
* data race ok: These are just statistics counters, and approximate
* statistics are ok for debugging.
*/
seq_printf(seq, "pools: %d\n", data_race(pools_num));
for (int i = 0; i < DEPOT_COUNTER_COUNT; i++)
seq_printf(seq, "%s: %ld\n", counter_names[i], data_race(counters[i]));
return 0;
}
DEFINE_SHOW_ATTRIBUTE(stats);
static int depot_debugfs_init(void)
{
struct dentry *dir;
if (stack_depot_disabled)
return 0;
dir = debugfs_create_dir("stackdepot", NULL);
debugfs_create_file("stats", 0444, dir, NULL, &stats_fops);
return 0;
}
late_initcall(depot_debugfs_init);

18
mm/huge_memory.c
View File

@ -37,6 +37,7 @@
#include <linux/page_owner.h>
#include <linux/sched/sysctl.h>
#include <linux/memory-tiers.h>
#include <linux/compat.h>
#include <asm/tlb.h>
#include <asm/pgalloc.h>
@ -809,7 +810,10 @@ static unsigned long __thp_get_unmapped_area(struct file *filp,
{
loff_t off_end = off + len;
loff_t off_align = round_up(off, size);
unsigned long len_pad, ret;
unsigned long len_pad, ret, off_sub;
if (IS_ENABLED(CONFIG_32BIT) || in_compat_syscall())
return 0;
if (off_end <= off_align || (off_end - off_align) < size)
return 0;
@ -835,7 +839,13 @@ static unsigned long __thp_get_unmapped_area(struct file *filp,
if (ret == addr)
return addr;
ret += (off - ret) & (size - 1);
off_sub = (off - ret) & (size - 1);
if (current->mm->get_unmapped_area == arch_get_unmapped_area_topdown &&
!off_sub)
return ret + size;
ret += off_sub;
return ret;
}
@ -2437,7 +2447,7 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd,
page = pmd_page(old_pmd);
folio = page_folio(page);
if (!folio_test_dirty(folio) && pmd_dirty(old_pmd))
folio_set_dirty(folio);
folio_mark_dirty(folio);
if (!folio_test_referenced(folio) && pmd_young(old_pmd))
folio_set_referenced(folio);
folio_remove_rmap_pmd(folio, page, vma);
@ -3563,7 +3573,7 @@ int set_pmd_migration_entry(struct page_vma_mapped_walk *pvmw,
}
if (pmd_dirty(pmdval))
folio_set_dirty(folio);
folio_mark_dirty(folio);
if (pmd_write(pmdval))
entry = make_writable_migration_entry(page_to_pfn(page));
else if (anon_exclusive)

29
mm/memcontrol.c
View File

@ -2623,8 +2623,9 @@ static unsigned long calculate_high_delay(struct mem_cgroup *memcg,
}
/*
* Scheduled by try_charge() to be executed from the userland return path
* and reclaims memory over the high limit.
* Reclaims memory over the high limit. Called directly from
* try_charge() (context permitting), as well as from the userland
* return path where reclaim is always able to block.
*/
void mem_cgroup_handle_over_high(gfp_t gfp_mask)
{
@ -2643,6 +2644,17 @@ void mem_cgroup_handle_over_high(gfp_t gfp_mask)
current->memcg_nr_pages_over_high = 0;
retry_reclaim:
/*
* Bail if the task is already exiting. Unlike memory.max,
* memory.high enforcement isn't as strict, and there is no
* OOM killer involved, which means the excess could already
* be much bigger (and still growing) than it could for
* memory.max; the dying task could get stuck in fruitless
* reclaim for a long time, which isn't desirable.
*/
if (task_is_dying())
goto out;
/*
* The allocating task should reclaim at least the batch size, but for
* subsequent retries we only want to do what's necessary to prevent oom
@ -2693,6 +2705,9 @@ retry_reclaim:
}
/*
* Reclaim didn't manage to push usage below the limit, slow
* this allocating task down.
*
* If we exit early, we're guaranteed to die (since
* schedule_timeout_killable sets TASK_KILLABLE). This means we don't
* need to account for any ill-begotten jiffies to pay them off later.
@ -2887,11 +2902,17 @@ done_restock:
}
} while ((memcg = parent_mem_cgroup(memcg)));
/*
* Reclaim is set up above to be called from the userland
* return path. But also attempt synchronous reclaim to avoid
* excessive overrun while the task is still inside the
* kernel. If this is successful, the return path will see it
* when it rechecks the overage and simply bail out.
*/
if (current->memcg_nr_pages_over_high > MEMCG_CHARGE_BATCH &&
!(current->flags & PF_MEMALLOC) &&
gfpflags_allow_blocking(gfp_mask)) {
gfpflags_allow_blocking(gfp_mask))
mem_cgroup_handle_over_high(gfp_mask);
}
return 0;
}

2
mm/memory-failure.c
View File

@ -982,7 +982,7 @@ static bool has_extra_refcount(struct page_state *ps, struct page *p,
int count = page_count(p) - 1;
if (extra_pins)
count -= 1;
count -= folio_nr_pages(page_folio(p));
if (count > 0) {
pr_err("%#lx: %s still referenced by %d users\n",

2
mm/memory.c
View File

@ -1464,7 +1464,7 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb,
delay_rmap = 0;
if (!folio_test_anon(folio)) {
if (pte_dirty(ptent)) {
folio_set_dirty(folio);
folio_mark_dirty(folio);
if (tlb_delay_rmap(tlb)) {
delay_rmap = 1;
force_flush = 1;

6
mm/mmap.c
View File

@ -1825,15 +1825,17 @@ get_unmapped_area(struct file *file, unsigned long addr, unsigned long len,
/*
* mmap_region() will call shmem_zero_setup() to create a file,
* so use shmem's get_unmapped_area in case it can be huge.
* do_mmap() will clear pgoff, so match alignment.
*/
pgoff = 0;
get_area = shmem_get_unmapped_area;
} else if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) {
/* Ensures that larger anonymous mappings are THP aligned. */
get_area = thp_get_unmapped_area;
}
/* Always treat pgoff as zero for anonymous memory. */
if (!file)
pgoff = 0;
addr = get_area(file, addr, len, pgoff, flags);
if (IS_ERR_VALUE(addr))
return addr;

2
mm/page-writeback.c
View File

@ -1638,7 +1638,7 @@ static inline void wb_dirty_limits(struct dirty_throttle_control *dtc)
*/
dtc->wb_thresh = __wb_calc_thresh(dtc);
dtc->wb_bg_thresh = dtc->thresh ?
div_u64((u64)dtc->wb_thresh * dtc->bg_thresh, dtc->thresh) : 0;
div64_u64(dtc->wb_thresh * dtc->bg_thresh, dtc->thresh) : 0;
/*
* In order to avoid the stacked BDI deadlock we need

4
mm/readahead.c
View File

@ -469,7 +469,7 @@ static inline int ra_alloc_folio(struct readahead_control *ractl, pgoff_t index,
if (!folio)
return -ENOMEM;
mark = round_up(mark, 1UL << order);
mark = round_down(mark, 1UL << order);
if (index == mark)
folio_set_readahead(folio);
err = filemap_add_folio(ractl->mapping, folio, index, gfp);
@ -575,7 +575,7 @@ static void ondemand_readahead(struct readahead_control *ractl,
* It's the expected callback index, assume sequential access.
* Ramp up sizes, and push forward the readahead window.
*/
expected = round_up(ra->start + ra->size - ra->async_size,
expected = round_down(ra->start + ra->size - ra->async_size,
1UL << order);
if (index == expected || index == (ra->start + ra->size)) {
ra->start += ra->size;

15
mm/userfaultfd.c
View File

@ -357,6 +357,7 @@ static __always_inline ssize_t mfill_atomic_hugetlb(
unsigned long dst_start,
unsigned long src_start,
unsigned long len,
atomic_t *mmap_changing,
uffd_flags_t flags)
{
struct mm_struct *dst_mm = dst_vma->vm_mm;
@ -472,6 +473,15 @@ retry:
goto out;
}
mmap_read_lock(dst_mm);
/*
* If memory mappings are changing because of non-cooperative
* operation (e.g. mremap) running in parallel, bail out and
* request the user to retry later
*/
if (mmap_changing && atomic_read(mmap_changing)) {
err = -EAGAIN;
break;
}
dst_vma = NULL;
goto retry;
@ -506,6 +516,7 @@ extern ssize_t mfill_atomic_hugetlb(struct vm_area_struct *dst_vma,
unsigned long dst_start,
unsigned long src_start,
unsigned long len,
atomic_t *mmap_changing,
uffd_flags_t flags);
#endif /* CONFIG_HUGETLB_PAGE */
@ -622,8 +633,8 @@ retry:
* If this is a HUGETLB vma, pass off to appropriate routine
*/
if (is_vm_hugetlb_page(dst_vma))
return mfill_atomic_hugetlb(dst_vma, dst_start,
src_start, len, flags);
return mfill_atomic_hugetlb(dst_vma, dst_start, src_start,
len, mmap_changing, flags);
if (!vma_is_anonymous(dst_vma) && !vma_is_shmem(dst_vma))
goto out_unlock;

2
tools/testing/selftests/mm/charge_reserved_hugetlb.sh
View File

@ -1,4 +1,4 @@
#!/bin/sh
#!/bin/bash
# SPDX-License-Identifier: GPL-2.0
# Kselftest framework requirement - SKIP code is 4.

2
tools/testing/selftests/mm/ksm_tests.c
View File

@ -566,7 +566,7 @@ static int ksm_merge_hugepages_time(int merge_type, int mapping, int prot,
if (map_ptr_orig == MAP_FAILED)
err(2, "initial mmap");
if (madvise(map_ptr, len + HPAGE_SIZE, MADV_HUGEPAGE))
if (madvise(map_ptr, len, MADV_HUGEPAGE))
err(2, "MADV_HUGEPAGE");
pagemap_fd = open("/proc/self/pagemap", O_RDONLY);

7
tools/testing/selftests/mm/map_hugetlb.c
View File

@ -15,6 +15,7 @@
#include <unistd.h>
#include <sys/mman.h>
#include <fcntl.h>
#include "vm_util.h"
#define LENGTH (256UL*1024*1024)
#define PROTECTION (PROT_READ | PROT_WRITE)
@ -58,10 +59,16 @@ int main(int argc, char **argv)
{
void *addr;
int ret;
size_t hugepage_size;
size_t length = LENGTH;
int flags = FLAGS;
int shift = 0;
hugepage_size = default_huge_page_size();
/* munmap with fail if the length is not page aligned */
if (hugepage_size > length)
length = hugepage_size;
if (argc > 1)
length = atol(argv[1]) << 20;
if (argc > 2) {

27
tools/testing/selftests/mm/mremap_test.c
View File

@ -360,7 +360,8 @@ static long long remap_region(struct config c, unsigned int threshold_mb,
char pattern_seed)
{
void *addr, *src_addr, *dest_addr, *dest_preamble_addr;
unsigned long long i;
int d;
unsigned long long t;
struct timespec t_start = {0, 0}, t_end = {0, 0};
long long start_ns, end_ns, align_mask, ret, offset;
unsigned long long threshold;
@ -378,8 +379,8 @@ static long long remap_region(struct config c, unsigned int threshold_mb,
/* Set byte pattern for source block. */
srand(pattern_seed);
for (i = 0; i < threshold; i++)
memset((char *) src_addr + i, (char) rand(), 1);
for (t = 0; t < threshold; t++)
memset((char *) src_addr + t, (char) rand(), 1);
/* Mask to zero out lower bits of address for alignment */
align_mask = ~(c.dest_alignment - 1);
@ -420,8 +421,8 @@ static long long remap_region(struct config c, unsigned int threshold_mb,
/* Set byte pattern for the dest preamble block. */
srand(pattern_seed);
for (i = 0; i < c.dest_preamble_size; i++)
memset((char *) dest_preamble_addr + i, (char) rand(), 1);
for (d = 0; d < c.dest_preamble_size; d++)
memset((char *) dest_preamble_addr + d, (char) rand(), 1);
}
clock_gettime(CLOCK_MONOTONIC, &t_start);
@ -437,14 +438,14 @@ static long long remap_region(struct config c, unsigned int threshold_mb,
/* Verify byte pattern after remapping */
srand(pattern_seed);
for (i = 0; i < threshold; i++) {
for (t = 0; t < threshold; t++) {
char c = (char) rand();
if (((char *) dest_addr)[i] != c) {
if (((char *) dest_addr)[t] != c) {
ksft_print_msg("Data after remap doesn't match at offset %llu\n",
i);
t);
ksft_print_msg("Expected: %#x\t Got: %#x\n", c & 0xff,
((char *) dest_addr)[i] & 0xff);
((char *) dest_addr)[t] & 0xff);
ret = -1;
goto clean_up_dest;
}
@ -453,14 +454,14 @@ static long long remap_region(struct config c, unsigned int threshold_mb,
/* Verify the dest preamble byte pattern after remapping */
if (c.dest_preamble_size) {
srand(pattern_seed);
for (i = 0; i < c.dest_preamble_size; i++) {
for (d = 0; d < c.dest_preamble_size; d++) {
char c = (char) rand();
if (((char *) dest_preamble_addr)[i] != c) {
if (((char *) dest_preamble_addr)[d] != c) {
ksft_print_msg("Preamble data after remap doesn't match at offset %d\n",
i);
d);
ksft_print_msg("Expected: %#x\t Got: %#x\n", c & 0xff,
((char *) dest_preamble_addr)[i] & 0xff);
((char *) dest_preamble_addr)[d] & 0xff);
ret = -1;
goto clean_up_dest;
}

6
tools/testing/selftests/mm/va_high_addr_switch.sh
View File

@ -29,9 +29,15 @@ check_supported_x86_64()
# See man 1 gzip under '-f'.
local pg_table_levels=$(gzip -dcfq "${config}" | grep PGTABLE_LEVELS | cut -d'=' -f 2)
local cpu_supports_pl5=$(awk '/^flags/ {if (/la57/) {print 0;}
else {print 1}; exit}' /proc/cpuinfo 2>/dev/null)
if [[ "${pg_table_levels}" -lt 5 ]]; then
echo "$0: PGTABLE_LEVELS=${pg_table_levels}, must be >= 5 to run this test"
exit $ksft_skip
elif [[ "${cpu_supports_pl5}" -ne 0 ]]; then
echo "$0: CPU does not have the necessary la57 flag to support page table level 5"
exit $ksft_skip
fi
}

2
tools/testing/selftests/mm/write_hugetlb_memory.sh
View File

@ -1,4 +1,4 @@
#!/bin/sh
#!/bin/bash
# SPDX-License-Identifier: GPL-2.0
set -e