diff options
Diffstat (limited to 'kernel/futex')
| -rw-r--r-- | kernel/futex/core.c | 16 | ||||
| -rw-r--r-- | kernel/futex/futex.h | 6 |
2 files changed, 15 insertions, 7 deletions
diff --git a/kernel/futex/core.c b/kernel/futex/core.c index d9bb5567af0c..125804fbb5cb 100644 --- a/kernel/futex/core.c +++ b/kernel/futex/core.c @@ -1722,12 +1722,9 @@ int futex_mm_init(struct mm_struct *mm) RCU_INIT_POINTER(mm->futex_phash, NULL); mm->futex_phash_new = NULL; /* futex-ref */ + mm->futex_ref = NULL; atomic_long_set(&mm->futex_atomic, 0); mm->futex_batches = get_state_synchronize_rcu(); - mm->futex_ref = alloc_percpu(unsigned int); - if (!mm->futex_ref) - return -ENOMEM; - this_cpu_inc(*mm->futex_ref); /* 0 -> 1 */ return 0; } @@ -1801,6 +1798,17 @@ static int futex_hash_allocate(unsigned int hash_slots, unsigned int flags) } } + if (!mm->futex_ref) { + /* + * This will always be allocated by the first thread and + * therefore requires no locking. + */ + mm->futex_ref = alloc_percpu(unsigned int); + if (!mm->futex_ref) + return -ENOMEM; + this_cpu_inc(*mm->futex_ref); /* 0 -> 1 */ + } + fph = kvzalloc(struct_size(fph, queues, hash_slots), GFP_KERNEL_ACCOUNT | __GFP_NOWARN); if (!fph) diff --git a/kernel/futex/futex.h b/kernel/futex/futex.h index c74eac572acd..2cd57096c38e 100644 --- a/kernel/futex/futex.h +++ b/kernel/futex/futex.h @@ -319,13 +319,13 @@ static __always_inline int futex_put_value(u32 val, u32 __user *to) { if (can_do_masked_user_access()) to = masked_user_access_begin(to); - else if (!user_read_access_begin(to, sizeof(*to))) + else if (!user_write_access_begin(to, sizeof(*to))) return -EFAULT; unsafe_put_user(val, to, Efault); - user_read_access_end(); + user_write_access_end(); return 0; Efault: - user_read_access_end(); + user_write_access_end(); return -EFAULT; } |