diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/audit.c | 12 | ||||
| -rw-r--r-- | kernel/cgroup.c | 11 | ||||
| -rw-r--r-- | kernel/futex.c | 53 | ||||
| -rw-r--r-- | kernel/time/timekeeping.c | 3 | ||||
| -rw-r--r-- | kernel/trace/trace.c | 27 | ||||
| -rw-r--r-- | kernel/trace/trace_events.c | 6 | ||||
| -rw-r--r-- | kernel/trace/trace_export.c | 7 |
7 files changed, 90 insertions, 29 deletions
diff --git a/kernel/audit.c b/kernel/audit.c index 3392d3e0254a..95a20f3f52f1 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -608,9 +608,19 @@ static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type) int err = 0; /* Only support the initial namespaces for now. */ + /* + * We return ECONNREFUSED because it tricks userspace into thinking + * that audit was not configured into the kernel. Lots of users + * configure their PAM stack (because that's what the distro does) + * to reject login if unable to send messages to audit. If we return + * ECONNREFUSED the PAM stack thinks the kernel does not have audit + * configured in and will let login proceed. If we return EPERM + * userspace will reject all logins. This should be removed when we + * support non init namespaces!! + */ if ((current_user_ns() != &init_user_ns) || (task_active_pid_ns(current) != &init_pid_ns)) - return -EPERM; + return -ECONNREFUSED; switch (msg_type) { case AUDIT_LIST: diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 105f273b6f86..0c753ddd223b 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -4112,17 +4112,17 @@ static int create_css(struct cgroup *cgrp, struct cgroup_subsys *ss) err = percpu_ref_init(&css->refcnt, css_release); if (err) - goto err_free; + goto err_free_css; init_css(css, ss, cgrp); err = cgroup_populate_dir(cgrp, 1 << ss->subsys_id); if (err) - goto err_free; + goto err_free_percpu_ref; err = online_css(css); if (err) - goto err_free; + goto err_clear_dir; dget(cgrp->dentry); css_get(css->parent); @@ -4138,8 +4138,11 @@ static int create_css(struct cgroup *cgrp, struct cgroup_subsys *ss) return 0; -err_free: +err_clear_dir: + cgroup_clear_dir(css->cgroup, 1 << css->ss->subsys_id); +err_free_percpu_ref: percpu_ref_cancel_init(&css->refcnt); +err_free_css: ss->css_free(css); return err; } diff --git a/kernel/futex.c b/kernel/futex.c index 44a1261cb9ff..08ec814ad9d2 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -234,6 +234,7 @@ static const struct futex_q futex_q_init = { * waiting on a futex. */ struct futex_hash_bucket { + atomic_t waiters; spinlock_t lock; struct plist_head chain; } ____cacheline_aligned_in_smp; @@ -253,22 +254,37 @@ static inline void futex_get_mm(union futex_key *key) smp_mb__after_atomic_inc(); } -static inline bool hb_waiters_pending(struct futex_hash_bucket *hb) +/* + * Reflects a new waiter being added to the waitqueue. + */ +static inline void hb_waiters_inc(struct futex_hash_bucket *hb) { #ifdef CONFIG_SMP + atomic_inc(&hb->waiters); /* - * Tasks trying to enter the critical region are most likely - * potential waiters that will be added to the plist. Ensure - * that wakers won't miss to-be-slept tasks in the window between - * the wait call and the actual plist_add. + * Full barrier (A), see the ordering comment above. */ - if (spin_is_locked(&hb->lock)) - return true; - smp_rmb(); /* Make sure we check the lock state first */ + smp_mb__after_atomic_inc(); +#endif +} + +/* + * Reflects a waiter being removed from the waitqueue by wakeup + * paths. + */ +static inline void hb_waiters_dec(struct futex_hash_bucket *hb) +{ +#ifdef CONFIG_SMP + atomic_dec(&hb->waiters); +#endif +} - return !plist_head_empty(&hb->chain); +static inline int hb_waiters_pending(struct futex_hash_bucket *hb) +{ +#ifdef CONFIG_SMP + return atomic_read(&hb->waiters); #else - return true; + return 1; #endif } @@ -954,6 +970,7 @@ static void __unqueue_futex(struct futex_q *q) hb = container_of(q->lock_ptr, struct futex_hash_bucket, lock); plist_del(&q->list, &hb->chain); + hb_waiters_dec(hb); } /* @@ -1257,7 +1274,9 @@ void requeue_futex(struct futex_q *q, struct futex_hash_bucket *hb1, */ if (likely(&hb1->chain != &hb2->chain)) { plist_del(&q->list, &hb1->chain); + hb_waiters_dec(hb1); plist_add(&q->list, &hb2->chain); + hb_waiters_inc(hb2); q->lock_ptr = &hb2->lock; } get_futex_key_refs(key2); @@ -1600,6 +1619,17 @@ static inline struct futex_hash_bucket *queue_lock(struct futex_q *q) struct futex_hash_bucket *hb; hb = hash_futex(&q->key); + + /* + * Increment the counter before taking the lock so that + * a potential waker won't miss a to-be-slept task that is + * waiting for the spinlock. This is safe as all queue_lock() + * users end up calling queue_me(). Similarly, for housekeeping, + * decrement the counter at queue_unlock() when some error has + * occurred and we don't end up adding the task to the list. + */ + hb_waiters_inc(hb); + q->lock_ptr = &hb->lock; spin_lock(&hb->lock); /* implies MB (A) */ @@ -1611,6 +1641,7 @@ queue_unlock(struct futex_hash_bucket *hb) __releases(&hb->lock) { spin_unlock(&hb->lock); + hb_waiters_dec(hb); } /** @@ -2342,6 +2373,7 @@ int handle_early_requeue_pi_wakeup(struct futex_hash_bucket *hb, * Unqueue the futex_q and determine which it was. */ plist_del(&q->list, &hb->chain); + hb_waiters_dec(hb); /* Handle spurious wakeups gracefully */ ret = -EWOULDBLOCK; @@ -2875,6 +2907,7 @@ static int __init futex_init(void) futex_cmpxchg_enabled = 1; for (i = 0; i < futex_hashsize; i++) { + atomic_set(&futex_queues[i].waiters, 0); plist_head_init(&futex_queues[i].chain); spin_lock_init(&futex_queues[i].lock); } diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 0aa4ce81bc16..5b40279ecd71 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -1435,7 +1435,8 @@ void update_wall_time(void) out: raw_spin_unlock_irqrestore(&timekeeper_lock, flags); if (clock_set) - clock_was_set(); + /* Have to call _delayed version, since in irq context*/ + clock_was_set_delayed(); } /** diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 815c878f409b..24c1f2382557 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -1600,15 +1600,31 @@ void trace_buffer_unlock_commit(struct ring_buffer *buffer, } EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); +static struct ring_buffer *temp_buffer; + struct ring_buffer_event * trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, struct ftrace_event_file *ftrace_file, int type, unsigned long len, unsigned long flags, int pc) { + struct ring_buffer_event *entry; + *current_rb = ftrace_file->tr->trace_buffer.buffer; - return trace_buffer_lock_reserve(*current_rb, + entry = trace_buffer_lock_reserve(*current_rb, type, len, flags, pc); + /* + * If tracing is off, but we have triggers enabled + * we still need to look at the event data. Use the temp_buffer + * to store the trace event for the tigger to use. It's recusive + * safe and will not be recorded anywhere. + */ + if (!entry && ftrace_file->flags & FTRACE_EVENT_FL_TRIGGER_COND) { + *current_rb = temp_buffer; + entry = trace_buffer_lock_reserve(*current_rb, + type, len, flags, pc); + } + return entry; } EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); @@ -6494,11 +6510,16 @@ __init static int tracer_alloc_buffers(void) raw_spin_lock_init(&global_trace.start_lock); + /* Used for event triggers */ + temp_buffer = ring_buffer_alloc(PAGE_SIZE, RB_FL_OVERWRITE); + if (!temp_buffer) + goto out_free_cpumask; + /* TODO: make the number of buffers hot pluggable with CPUS */ if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); WARN_ON(1); - goto out_free_cpumask; + goto out_free_temp_buffer; } if (global_trace.buffer_disabled) @@ -6540,6 +6561,8 @@ __init static int tracer_alloc_buffers(void) return 0; +out_free_temp_buffer: + ring_buffer_free(temp_buffer); out_free_cpumask: free_percpu(global_trace.trace_buffer.data); #ifdef CONFIG_TRACER_MAX_TRACE diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index f3989ceb5cd5..7b16d40bd64d 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -27,12 +27,6 @@ DEFINE_MUTEX(event_mutex); -DEFINE_MUTEX(event_storage_mutex); -EXPORT_SYMBOL_GPL(event_storage_mutex); - -char event_storage[EVENT_STORAGE_SIZE]; -EXPORT_SYMBOL_GPL(event_storage); - LIST_HEAD(ftrace_events); static LIST_HEAD(ftrace_common_fields); diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c index 7c3e3e72e2b6..ee0a5098ac43 100644 --- a/kernel/trace/trace_export.c +++ b/kernel/trace/trace_export.c @@ -95,15 +95,12 @@ static void __always_unused ____ftrace_check_##name(void) \ #undef __array #define __array(type, item, len) \ do { \ + char *type_str = #type"["__stringify(len)"]"; \ BUILD_BUG_ON(len > MAX_FILTER_STR_VAL); \ - mutex_lock(&event_storage_mutex); \ - snprintf(event_storage, sizeof(event_storage), \ - "%s[%d]", #type, len); \ - ret = trace_define_field(event_call, event_storage, #item, \ + ret = trace_define_field(event_call, type_str, #item, \ offsetof(typeof(field), item), \ sizeof(field.item), \ is_signed_type(type), filter_type); \ - mutex_unlock(&event_storage_mutex); \ if (ret) \ return ret; \ } while (0); |