diff options
| -rw-r--r-- | include/linux/mempolicy.h | 1 | ||||
| -rw-r--r-- | kernel/futex/core.c | 2 | ||||
| -rw-r--r-- | kernel/futex/pi.c | 3 | ||||
| -rw-r--r-- | kernel/futex/syscalls.c | 8 | ||||
| -rw-r--r-- | mm/mempolicy.c | 10 |
5 files changed, 20 insertions, 4 deletions
diff --git a/include/linux/mempolicy.h b/include/linux/mempolicy.h index 0fe96f3ab3ef..65c732d440d2 100644 --- a/include/linux/mempolicy.h +++ b/include/linux/mempolicy.h @@ -55,6 +55,7 @@ struct mempolicy { nodemask_t cpuset_mems_allowed; /* relative to these nodes */ nodemask_t user_nodemask; /* nodemask passed by user */ } w; + struct rcu_head rcu; }; /* diff --git a/kernel/futex/core.c b/kernel/futex/core.c index cf7e610eac42..31e83a09789e 100644 --- a/kernel/futex/core.c +++ b/kernel/futex/core.c @@ -342,7 +342,7 @@ static int __futex_key_to_node(struct mm_struct *mm, unsigned long addr) if (!vma) return FUTEX_NO_NODE; - mpol = vma_policy(vma); + mpol = READ_ONCE(vma->vm_policy); if (!mpol) return FUTEX_NO_NODE; diff --git a/kernel/futex/pi.c b/kernel/futex/pi.c index bc1f7e83a37e..7808068fa59e 100644 --- a/kernel/futex/pi.c +++ b/kernel/futex/pi.c @@ -918,7 +918,7 @@ int fixup_pi_owner(u32 __user *uaddr, struct futex_q *q, int locked) int futex_lock_pi(u32 __user *uaddr, unsigned int flags, ktime_t *time, int trylock) { struct hrtimer_sleeper timeout, *to; - struct task_struct *exiting = NULL; + struct task_struct *exiting; struct rt_mutex_waiter rt_waiter; struct futex_q q = futex_q_init; DEFINE_WAKE_Q(wake_q); @@ -933,6 +933,7 @@ int futex_lock_pi(u32 __user *uaddr, unsigned int flags, ktime_t *time, int tryl to = futex_setup_timer(time, &timeout, flags, 0); retry: + exiting = NULL; ret = get_futex_key(uaddr, flags, &q.key, FUTEX_WRITE); if (unlikely(ret != 0)) goto out; diff --git a/kernel/futex/syscalls.c b/kernel/futex/syscalls.c index 743c7a728237..77ad9691f6a6 100644 --- a/kernel/futex/syscalls.c +++ b/kernel/futex/syscalls.c @@ -459,6 +459,14 @@ SYSCALL_DEFINE4(futex_requeue, if (ret) return ret; + /* + * For now mandate both flags are identical, like the sys_futex() + * interface has. If/when we merge the variable sized futex support, + * that patch can modify this test to allow a difference in size. + */ + if (futexes[0].w.flags != futexes[1].w.flags) + return -EINVAL; + cmpval = futexes[0].w.val; return futex_requeue(u64_to_user_ptr(futexes[0].w.uaddr), futexes[0].w.flags, diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 0e5175f1c767..cf92bd6a8226 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -487,7 +487,13 @@ void __mpol_put(struct mempolicy *pol) { if (!atomic_dec_and_test(&pol->refcnt)) return; - kmem_cache_free(policy_cache, pol); + /* + * Required to allow mmap_lock_speculative*() access, see for example + * futex_key_to_node_opt(). All accesses are serialized by mmap_lock, + * however the speculative lock section unbound by the normal lock + * boundaries, requiring RCU freeing. + */ + kfree_rcu(pol, rcu); } EXPORT_SYMBOL_FOR_MODULES(__mpol_put, "kvm"); @@ -1020,7 +1026,7 @@ static int vma_replace_policy(struct vm_area_struct *vma, } old = vma->vm_policy; - vma->vm_policy = new; /* protected by mmap_lock */ + WRITE_ONCE(vma->vm_policy, new); /* protected by mmap_lock */ mpol_put(old); return 0; |