Merge 3.9-rc4 into driver-core-next

This is to fix up a build problem with a wireless driver due to the
dynamic-debug patches in this branch.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

9 files changed, 112 insertions, 34 deletions

diff --git a/kernel/async.c b/kernel/async.c
index 9d3118384858..a1d585c351d6 100644
--- a/kernel/async.c
+++ b/kernel/async.c
@@ -196,6 +196,9 @@ static async_cookie_t __async_schedule(async_func_ptr *ptr, void *data, struct a
         atomic_inc(&entry_count);
         spin_unlock_irqrestore(&async_lock, flags);
 
+        /* mark that this task has queued an async job, used by module init */
+        current->flags |= PF_USED_ASYNC;
+
         /* schedule for execution */
         queue_work(system_unbound_wq, &entry->work);
 
diff --git a/kernel/audit.c b/kernel/audit.c
index 40414e9143db..d596e5355f15 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -272,6 +272,8 @@ static int audit_log_config_change(char *function_name, int new, int old,
         int rc = 0;
 
         ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
+        if (unlikely(!ab))
+                return rc;
         audit_log_format(ab, "%s=%d old=%d auid=%u ses=%u", function_name, new,
                          old, from_kuid(&init_user_ns, loginuid), sessionid);
         if (sid) {
@@ -619,6 +621,8 @@ static int audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type,
         }
 
         *ab = audit_log_start(NULL, GFP_KERNEL, msg_type);
+        if (unlikely(!*ab))
+                return rc;
         audit_log_format(*ab, "pid=%d uid=%u auid=%u ses=%u",
                          task_tgid_vnr(current),
                          from_kuid(&init_user_ns, current_uid()),
@@ -1097,6 +1101,23 @@ static inline void audit_get_stamp(struct audit_context *ctx,
         }
 }
 
+/*
+ * Wait for auditd to drain the queue a little
+ */
+static void wait_for_auditd(unsigned long sleep_time)
+{
+        DECLARE_WAITQUEUE(wait, current);
+        set_current_state(TASK_INTERRUPTIBLE);
+        add_wait_queue(&audit_backlog_wait, &wait);
+
+        if (audit_backlog_limit &&
+            skb_queue_len(&audit_skb_queue) > audit_backlog_limit)
+                schedule_timeout(sleep_time);
+
+        __set_current_state(TASK_RUNNING);
+        remove_wait_queue(&audit_backlog_wait, &wait);
+}
+
 /* Obtain an audit buffer.  This routine does locking to obtain the
  * audit buffer, but then no locking is required for calls to
  * audit_log_*format.  If the tsk is a task that is currently in a
@@ -1142,20 +1163,13 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask,
 
         while (audit_backlog_limit
                && skb_queue_len(&audit_skb_queue) > audit_backlog_limit + reserve) {
-                if (gfp_mask & __GFP_WAIT && audit_backlog_wait_time
-                    && time_before(jiffies, timeout_start + audit_backlog_wait_time)) {
+                if (gfp_mask & __GFP_WAIT && audit_backlog_wait_time) {
+                        unsigned long sleep_time;
 
-                        /* Wait for auditd to drain the queue a little */
-                        DECLARE_WAITQUEUE(wait, current);
-                        set_current_state(TASK_INTERRUPTIBLE);
-                        add_wait_queue(&audit_backlog_wait, &wait);
-
-                        if (audit_backlog_limit &&
-                            skb_queue_len(&audit_skb_queue) > audit_backlog_limit)
-                                schedule_timeout(timeout_start + audit_backlog_wait_time - jiffies);
-
-                        __set_current_state(TASK_RUNNING);
-                        remove_wait_queue(&audit_backlog_wait, &wait);
+                        sleep_time = timeout_start + audit_backlog_wait_time -
+                                        jiffies;
+                        if ((long)sleep_time > 0)
+                                wait_for_auditd(sleep_time);
                         continue;
                 }
                 if (audit_rate_check() && printk_ratelimit())
diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c
index e81175ef25f8..642a89c4f3d6 100644
--- a/kernel/audit_tree.c
+++ b/kernel/audit_tree.c
@@ -449,11 +449,26 @@ static int tag_chunk(struct inode *inode, struct audit_tree *tree)
         return 0;
 }
 
+static void audit_log_remove_rule(struct audit_krule *rule)
+{
+        struct audit_buffer *ab;
+
+        ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
+        if (unlikely(!ab))
+                return;
+        audit_log_format(ab, "op=");
+        audit_log_string(ab, "remove rule");
+        audit_log_format(ab, " dir=");
+        audit_log_untrustedstring(ab, rule->tree->pathname);
+        audit_log_key(ab, rule->filterkey);
+        audit_log_format(ab, " list=%d res=1", rule->listnr);
+        audit_log_end(ab);
+}
+
 static void kill_rules(struct audit_tree *tree)
 {
         struct audit_krule *rule, *next;
         struct audit_entry *entry;
-        struct audit_buffer *ab;
 
         list_for_each_entry_safe(rule, next, &tree->rules, rlist) {
                 entry = container_of(rule, struct audit_entry, rule);
@@ -461,14 +476,7 @@ static void kill_rules(struct audit_tree *tree)
                 list_del_init(&rule->rlist);
                 if (rule->tree) {
                         /* not a half-baked one */
-                        ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
-                        audit_log_format(ab, "op=");
-                        audit_log_string(ab, "remove rule");
-                        audit_log_format(ab, " dir=");
-                        audit_log_untrustedstring(ab, rule->tree->pathname);
-                        audit_log_key(ab, rule->filterkey);
-                        audit_log_format(ab, " list=%d res=1", rule->listnr);
-                        audit_log_end(ab);
+                        audit_log_remove_rule(rule);
                         rule->tree = NULL;
                         list_del_rcu(&entry->list);
                         list_del(&entry->rule.list);
diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c
index 4a599f699adc..22831c4d369c 100644
--- a/kernel/audit_watch.c
+++ b/kernel/audit_watch.c
@@ -240,6 +240,8 @@ static void audit_watch_log_rule_change(struct audit_krule *r, struct audit_watc
         if (audit_enabled) {
                 struct audit_buffer *ab;
                 ab = audit_log_start(NULL, GFP_NOFS, AUDIT_CONFIG_CHANGE);
+                if (unlikely(!ab))
+                        return;
                 audit_log_format(ab, "auid=%u ses=%u op=",
                                  from_kuid(&init_user_ns, audit_get_loginuid(current)),
                                  audit_get_sessionid(current));
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index 7f19f23d38a3..f9fc54bbe06f 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -1144,7 +1144,6 @@ static void audit_log_rule_change(kuid_t loginuid, u32 sessionid, u32 sid,
  * audit_receive_filter - apply all rules to the specified message type
  * @type: audit message type
  * @pid: target pid for netlink audit messages
- * @uid: target uid for netlink audit messages
  * @seq: netlink audit message sequence (serial) number
  * @data: payload data
  * @datasz: size of payload data
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index e37e6a12c5e3..a371f857a0a9 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -1464,14 +1464,14 @@ static void show_special(struct audit_context *context, int *call_panic)
                         audit_log_end(ab);
                         ab = audit_log_start(context, GFP_KERNEL,
                                              AUDIT_IPC_SET_PERM);
+                        if (unlikely(!ab))
+                                return;
                         audit_log_format(ab,
                                 "qbytes=%lx ouid=%u ogid=%u mode=%#ho",
                                 context->ipc.qbytes,
                                 context->ipc.perm_uid,
                                 context->ipc.perm_gid,
                                 context->ipc.perm_mode);
-                        if (!ab)
-                                return;
                 }
                 break; }
         case AUDIT_MQ_OPEN: {
@@ -2675,7 +2675,7 @@ void __audit_mmap_fd(int fd, int flags)
         context->type = AUDIT_MMAP;
 }
 
-static void audit_log_abend(struct audit_buffer *ab, char *reason, long signr)
+static void audit_log_task(struct audit_buffer *ab)
 {
         kuid_t auid, uid;
         kgid_t gid;
@@ -2693,6 +2693,11 @@ static void audit_log_abend(struct audit_buffer *ab, char *reason, long signr)
         audit_log_task_context(ab);
         audit_log_format(ab, " pid=%d comm=", current->pid);
         audit_log_untrustedstring(ab, current->comm);
+}
+
+static void audit_log_abend(struct audit_buffer *ab, char *reason, long signr)
+{
+        audit_log_task(ab);
         audit_log_format(ab, " reason=");
         audit_log_string(ab, reason);
         audit_log_format(ab, " sig=%ld", signr);
@@ -2715,6 +2720,8 @@ void audit_core_dumps(long signr)
                 return;
 
         ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
+        if (unlikely(!ab))
+                return;
         audit_log_abend(ab, "memory violation", signr);
         audit_log_end(ab);
 }
@@ -2723,8 +2730,11 @@ void __audit_seccomp(unsigned long syscall, long signr, int code)
 {
         struct audit_buffer *ab;
 
-        ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
-        audit_log_abend(ab, "seccomp", signr);
+        ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_SECCOMP);
+        if (unlikely(!ab))
+                return;
+        audit_log_task(ab);
+        audit_log_format(ab, " sig=%ld", signr);
         audit_log_format(ab, " syscall=%ld", syscall);
         audit_log_format(ab, " compat=%d", is_compat_task());
         audit_log_format(ab, " ip=0x%lx", KSTK_EIP(current));
diff --git a/kernel/module.c b/kernel/module.c
index 250092c1d57d..b10b048367e1 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -3013,6 +3013,12 @@ static int do_init_module(struct module *mod)
 {
         int ret = 0;
 
+        /*
+         * We want to find out whether @mod uses async during init.  Clear
+         * PF_USED_ASYNC.  async_schedule*() will set it.
+         */
+        current->flags &= ~PF_USED_ASYNC;
+
         blocking_notifier_call_chain(&module_notify_list,
                         MODULE_STATE_COMING, mod);
 
@@ -3058,8 +3064,25 @@ static int do_init_module(struct module *mod)
         blocking_notifier_call_chain(&module_notify_list,
                                      MODULE_STATE_LIVE, mod);
 
-        /* We need to finish all async code before the module init sequence is done */
-        async_synchronize_full();
+        /*
+         * We need to finish all async code before the module init sequence
+         * is done.  This has potential to deadlock.  For example, a newly
+         * detected block device can trigger request_module() of the
+         * default iosched from async probing task.  Once userland helper
+         * reaches here, async_synchronize_full() will wait on the async
+         * task waiting on request_module() and deadlock.
+         *
+         * This deadlock is avoided by perfomring async_synchronize_full()
+         * iff module init queued any async jobs.  This isn't a full
+         * solution as it will deadlock the same if module loading from
+         * async jobs nests more than once; however, due to the various
+         * constraints, this hack seems to be the best option for now.
+         * Please refer to the following thread for details.
+         *
+         * http://thread.gmane.org/gmane.linux.kernel/1420814
+         */
+        if (current->flags & PF_USED_ASYNC)
+                async_synchronize_full();
 
         mutex_lock(&module_mutex);
         /* Drop initial reference. */
diff --git a/kernel/rwsem.c b/kernel/rwsem.c
index 6850f53e02d8..b3c6c3fcd847 100644
--- a/kernel/rwsem.c
+++ b/kernel/rwsem.c
@@ -116,6 +116,16 @@ void down_read_nested(struct rw_semaphore *sem, int subclass)
 
 EXPORT_SYMBOL(down_read_nested);
 
+void _down_write_nest_lock(struct rw_semaphore *sem, struct lockdep_map *nest)
+{
+        might_sleep();
+        rwsem_acquire_nest(&sem->dep_map, 0, 0, nest, _RET_IP_);
+
+        LOCK_CONTENDED(sem, __down_write_trylock, __down_write);
+}
+
+EXPORT_SYMBOL(_down_write_nest_lock);
+
 void down_write_nested(struct rw_semaphore *sem, int subclass)
 {
         might_sleep();
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index e5125677efa0..3c13e46d7d24 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2899,6 +2899,8 @@ tracing_trace_options_write(struct file *filp, const char __user *ubuf,
         if (copy_from_user(&buf, ubuf, cnt))
                 return -EFAULT;
 
+        buf[cnt] = 0;
+
         trace_set_options(buf);
 
         *ppos += cnt;
@@ -3452,7 +3454,7 @@ static int tracing_wait_pipe(struct file *filp)
                         return -EINTR;
 
                 /*
-                 * We block until we read something and tracing is enabled.
+                 * We block until we read something and tracing is disabled.
                  * We still block if tracing is disabled, but we have never
                  * read anything. This allows a user to cat this file, and
                  * then enable tracing. But after we have read something,
@@ -3460,7 +3462,7 @@ static int tracing_wait_pipe(struct file *filp)
                  *
                  * iter->pos will be 0 if we haven't read anything.
                  */
-                if (tracing_is_enabled() && iter->pos)
+                if (!tracing_is_enabled() && iter->pos)
                         break;
         }
 
@@ -4815,10 +4817,17 @@ rb_simple_write(struct file *filp, const char __user *ubuf,
                 return ret;
 
         if (buffer) {
-                if (val)
+                mutex_lock(&trace_types_lock);
+                if (val) {
                         ring_buffer_record_on(buffer);
-                else
+                        if (current_trace->start)
+                                current_trace->start(tr);
+                } else {
                         ring_buffer_record_off(buffer);
+                        if (current_trace->stop)
+                                current_trace->stop(tr);
+                }
+                mutex_unlock(&trace_types_lock);
         }
 
         (*ppos)++;