aboutsummaryrefslogtreecommitdiff
path: root/kernel
diff options
context:
space:
mode:
Diffstat (limited to 'kernel')
-rw-r--r--kernel/fork.c5
-rw-r--r--kernel/futex.c46
-rw-r--r--kernel/signal.c5
-rw-r--r--kernel/smpboot.c4
-rw-r--r--kernel/softirq.c21
-rw-r--r--kernel/stop_machine.c2
-rw-r--r--kernel/trace/Kconfig24
-rw-r--r--kernel/trace/trace.c27
-rw-r--r--kernel/user_namespace.c4
-rw-r--r--kernel/workqueue.c51
10 files changed, 115 insertions, 74 deletions
diff --git a/kernel/fork.c b/kernel/fork.c
index 8d932b1c905..1766d324d5e 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1141,6 +1141,9 @@ static struct task_struct *copy_process(unsigned long clone_flags,
if ((clone_flags & (CLONE_NEWNS|CLONE_FS)) == (CLONE_NEWNS|CLONE_FS))
return ERR_PTR(-EINVAL);
+ if ((clone_flags & (CLONE_NEWUSER|CLONE_FS)) == (CLONE_NEWUSER|CLONE_FS))
+ return ERR_PTR(-EINVAL);
+
/*
* Thread groups must share signals as well, and detached threads
* can only be started up within the thread group.
@@ -1807,7 +1810,7 @@ SYSCALL_DEFINE1(unshare, unsigned long, unshare_flags)
* If unsharing a user namespace must also unshare the thread.
*/
if (unshare_flags & CLONE_NEWUSER)
- unshare_flags |= CLONE_THREAD;
+ unshare_flags |= CLONE_THREAD | CLONE_FS;
/*
* If unsharing a pid namespace must also unshare the thread.
*/
diff --git a/kernel/futex.c b/kernel/futex.c
index f0090a993da..b26dcfc02c9 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -223,7 +223,8 @@ static void drop_futex_key_refs(union futex_key *key)
* @rw: mapping needs to be read/write (values: VERIFY_READ,
* VERIFY_WRITE)
*
- * Returns a negative error code or 0
+ * Return: a negative error code or 0
+ *
* The key words are stored in *key on success.
*
* For shared mappings, it's (page->index, file_inode(vma->vm_file),
@@ -705,9 +706,9 @@ lookup_pi_state(u32 uval, struct futex_hash_bucket *hb,
* be "current" except in the case of requeue pi.
* @set_waiters: force setting the FUTEX_WAITERS bit (1) or not (0)
*
- * Returns:
- * 0 - ready to wait
- * 1 - acquired the lock
+ * Return:
+ * 0 - ready to wait;
+ * 1 - acquired the lock;
* <0 - error
*
* The hb->lock and futex_key refs shall be held by the caller.
@@ -1191,9 +1192,9 @@ void requeue_pi_wake_futex(struct futex_q *q, union futex_key *key,
* then direct futex_lock_pi_atomic() to force setting the FUTEX_WAITERS bit.
* hb1 and hb2 must be held by the caller.
*
- * Returns:
- * 0 - failed to acquire the lock atomicly
- * 1 - acquired the lock
+ * Return:
+ * 0 - failed to acquire the lock atomically;
+ * 1 - acquired the lock;
* <0 - error
*/
static int futex_proxy_trylock_atomic(u32 __user *pifutex,
@@ -1254,8 +1255,8 @@ static int futex_proxy_trylock_atomic(u32 __user *pifutex,
* Requeue waiters on uaddr1 to uaddr2. In the requeue_pi case, try to acquire
* uaddr2 atomically on behalf of the top waiter.
*
- * Returns:
- * >=0 - on success, the number of tasks requeued or woken
+ * Return:
+ * >=0 - on success, the number of tasks requeued or woken;
* <0 - on error
*/
static int futex_requeue(u32 __user *uaddr1, unsigned int flags,
@@ -1536,8 +1537,8 @@ static inline void queue_me(struct futex_q *q, struct futex_hash_bucket *hb)
* The q->lock_ptr must not be held by the caller. A call to unqueue_me() must
* be paired with exactly one earlier call to queue_me().
*
- * Returns:
- * 1 - if the futex_q was still queued (and we removed unqueued it)
+ * Return:
+ * 1 - if the futex_q was still queued (and we removed unqueued it);
* 0 - if the futex_q was already removed by the waking thread
*/
static int unqueue_me(struct futex_q *q)
@@ -1707,9 +1708,9 @@ static long futex_wait_restart(struct restart_block *restart);
* the pi_state owner as well as handle race conditions that may allow us to
* acquire the lock. Must be called with the hb lock held.
*
- * Returns:
- * 1 - success, lock taken
- * 0 - success, lock not taken
+ * Return:
+ * 1 - success, lock taken;
+ * 0 - success, lock not taken;
* <0 - on error (-EFAULT)
*/
static int fixup_owner(u32 __user *uaddr, struct futex_q *q, int locked)
@@ -1824,8 +1825,8 @@ static void futex_wait_queue_me(struct futex_hash_bucket *hb, struct futex_q *q,
* Return with the hb lock held and a q.key reference on success, and unlocked
* with no q.key reference on failure.
*
- * Returns:
- * 0 - uaddr contains val and hb has been locked
+ * Return:
+ * 0 - uaddr contains val and hb has been locked;
* <1 - -EFAULT or -EWOULDBLOCK (uaddr does not contain val) and hb is unlocked
*/
static int futex_wait_setup(u32 __user *uaddr, u32 val, unsigned int flags,
@@ -2203,9 +2204,9 @@ pi_faulted:
* the wakeup and return the appropriate error code to the caller. Must be
* called with the hb lock held.
*
- * Returns
- * 0 - no early wakeup detected
- * <0 - -ETIMEDOUT or -ERESTARTNOINTR
+ * Return:
+ * 0 = no early wakeup detected;
+ * <0 = -ETIMEDOUT or -ERESTARTNOINTR
*/
static inline
int handle_early_requeue_pi_wakeup(struct futex_hash_bucket *hb,
@@ -2247,7 +2248,6 @@ int handle_early_requeue_pi_wakeup(struct futex_hash_bucket *hb,
* @val: the expected value of uaddr
* @abs_time: absolute timeout
* @bitset: 32 bit wakeup bitset set by userspace, defaults to all
- * @clockrt: whether to use CLOCK_REALTIME (1) or CLOCK_MONOTONIC (0)
* @uaddr2: the pi futex we will take prior to returning to user-space
*
* The caller will wait on uaddr and will be requeued by futex_requeue() to
@@ -2258,7 +2258,7 @@ int handle_early_requeue_pi_wakeup(struct futex_hash_bucket *hb,
* there was a need to.
*
* We call schedule in futex_wait_queue_me() when we enqueue and return there
- * via the following:
+ * via the following--
* 1) wakeup on uaddr2 after an atomic lock acquisition by futex_requeue()
* 2) wakeup on uaddr2 after a requeue
* 3) signal
@@ -2276,8 +2276,8 @@ int handle_early_requeue_pi_wakeup(struct futex_hash_bucket *hb,
*
* If 4 or 7, we cleanup and return with -ETIMEDOUT.
*
- * Returns:
- * 0 - On success
+ * Return:
+ * 0 - On success;
* <0 - On error
*/
static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
diff --git a/kernel/signal.c b/kernel/signal.c
index 2ec870a4c3c..dd72567767d 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -485,6 +485,9 @@ flush_signal_handlers(struct task_struct *t, int force_default)
if (force_default || ka->sa.sa_handler != SIG_IGN)
ka->sa.sa_handler = SIG_DFL;
ka->sa.sa_flags = 0;
+#ifdef __ARCH_HAS_SA_RESTORER
+ ka->sa.sa_restorer = NULL;
+#endif
sigemptyset(&ka->sa.sa_mask);
ka++;
}
@@ -2682,7 +2685,7 @@ static int do_sigpending(void *set, unsigned long sigsetsize)
/**
* sys_rt_sigpending - examine a pending signal that has been raised
* while blocked
- * @set: stores pending signals
+ * @uset: stores pending signals
* @sigsetsize: size of sigset_t type or larger
*/
SYSCALL_DEFINE2(rt_sigpending, sigset_t __user *, uset, size_t, sigsetsize)
diff --git a/kernel/smpboot.c b/kernel/smpboot.c
index b9bde572782..8eaed9aa9cf 100644
--- a/kernel/smpboot.c
+++ b/kernel/smpboot.c
@@ -131,7 +131,7 @@ static int smpboot_thread_fn(void *data)
continue;
}
- //BUG_ON(td->cpu != smp_processor_id());
+ BUG_ON(td->cpu != smp_processor_id());
/* Check for state change setup */
switch (td->status) {
@@ -209,6 +209,8 @@ static void smpboot_unpark_thread(struct smp_hotplug_thread *ht, unsigned int cp
{
struct task_struct *tsk = *per_cpu_ptr(ht->store, cpu);
+ if (ht->pre_unpark)
+ ht->pre_unpark(cpu);
kthread_unpark(tsk);
}
diff --git a/kernel/softirq.c b/kernel/softirq.c
index b4d252fd195..14d7758074a 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -323,18 +323,10 @@ void irq_enter(void)
static inline void invoke_softirq(void)
{
- if (!force_irqthreads) {
-#ifdef __ARCH_IRQ_EXIT_IRQS_DISABLED
+ if (!force_irqthreads)
__do_softirq();
-#else
- do_softirq();
-#endif
- } else {
- __local_bh_disable((unsigned long)__builtin_return_address(0),
- SOFTIRQ_OFFSET);
+ else
wakeup_softirqd();
- __local_bh_enable(SOFTIRQ_OFFSET);
- }
}
/*
@@ -342,9 +334,15 @@ static inline void invoke_softirq(void)
*/
void irq_exit(void)
{
+#ifndef __ARCH_IRQ_EXIT_IRQS_DISABLED
+ local_irq_disable();
+#else
+ WARN_ON_ONCE(!irqs_disabled());
+#endif
+
account_irq_exit_time(current);
trace_hardirq_exit();
- sub_preempt_count(IRQ_EXIT_OFFSET);
+ sub_preempt_count(HARDIRQ_OFFSET);
if (!in_interrupt() && local_softirq_pending())
invoke_softirq();
@@ -354,7 +352,6 @@ void irq_exit(void)
tick_nohz_irq_exit();
#endif
rcu_irq_exit();
- sched_preempt_enable_no_resched();
}
/*
diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c
index 95d178c62d5..c09f2955ae3 100644
--- a/kernel/stop_machine.c
+++ b/kernel/stop_machine.c
@@ -336,7 +336,7 @@ static struct smp_hotplug_thread cpu_stop_threads = {
.create = cpu_stop_create,
.setup = cpu_stop_unpark,
.park = cpu_stop_park,
- .unpark = cpu_stop_unpark,
+ .pre_unpark = cpu_stop_unpark,
.selfparking = true,
};
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 192473b2279..fc382d6e276 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -414,24 +414,28 @@ config PROBE_EVENTS
def_bool n
config DYNAMIC_FTRACE
- bool "enable/disable ftrace tracepoints dynamically"
+ bool "enable/disable function tracing dynamically"
depends on FUNCTION_TRACER
depends on HAVE_DYNAMIC_FTRACE
default y
help
- This option will modify all the calls to ftrace dynamically
- (will patch them out of the binary image and replace them
- with a No-Op instruction) as they are called. A table is
- created to dynamically enable them again.
+ This option will modify all the calls to function tracing
+ dynamically (will patch them out of the binary image and
+ replace them with a No-Op instruction) on boot up. During
+ compile time, a table is made of all the locations that ftrace
+ can function trace, and this table is linked into the kernel
+ image. When this is enabled, functions can be individually
+ enabled, and the functions not enabled will not affect
+ performance of the system.
+
+ See the files in /sys/kernel/debug/tracing:
+ available_filter_functions
+ set_ftrace_filter
+ set_ftrace_notrace
This way a CONFIG_FUNCTION_TRACER kernel is slightly larger, but
otherwise has native performance as long as no tracing is active.
- The changes to the code are done by a kernel thread that
- wakes up once a second and checks to see if any ftrace calls
- were made. If so, it runs stop_machine (stops all CPUS)
- and modifies the code to jump over the call to ftrace.
-
config DYNAMIC_FTRACE_WITH_REGS
def_bool y
depends on DYNAMIC_FTRACE
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index c2e2c231037..1f835a83cb2 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2400,6 +2400,27 @@ static void test_ftrace_alive(struct seq_file *m)
seq_printf(m, "# MAY BE MISSING FUNCTION EVENTS\n");
}
+#ifdef CONFIG_TRACER_MAX_TRACE
+static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter)
+{
+ if (iter->trace->allocated_snapshot)
+ seq_printf(m, "#\n# * Snapshot is allocated *\n#\n");
+ else
+ seq_printf(m, "#\n# * Snapshot is freed *\n#\n");
+
+ seq_printf(m, "# Snapshot commands:\n");
+ seq_printf(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n");
+ seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n");
+ seq_printf(m, "# Takes a snapshot of the main buffer.\n");
+ seq_printf(m, "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate)\n");
+ seq_printf(m, "# (Doesn't have to be '2' works with any number that\n");
+ seq_printf(m, "# is not a '0' or '1')\n");
+}
+#else
+/* Should never be called */
+static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { }
+#endif
+
static int s_show(struct seq_file *m, void *v)
{
struct trace_iterator *iter = v;
@@ -2411,7 +2432,9 @@ static int s_show(struct seq_file *m, void *v)
seq_puts(m, "#\n");
test_ftrace_alive(m);
}
- if (iter->trace && iter->trace->print_header)
+ if (iter->snapshot && trace_empty(iter))
+ print_snapshot_help(m, iter);
+ else if (iter->trace && iter->trace->print_header)
iter->trace->print_header(m);
else
trace_default_header(m);
@@ -4144,8 +4167,6 @@ tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt,
default:
if (current_trace->allocated_snapshot)
tracing_reset_online_cpus(&max_tr);
- else
- ret = -EINVAL;
break;
}
diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c
index 8b650837083..b14f4d34204 100644
--- a/kernel/user_namespace.c
+++ b/kernel/user_namespace.c
@@ -21,6 +21,7 @@
#include <linux/uaccess.h>
#include <linux/ctype.h>
#include <linux/projid.h>
+#include <linux/fs_struct.h>
static struct kmem_cache *user_ns_cachep __read_mostly;
@@ -837,6 +838,9 @@ static int userns_install(struct nsproxy *nsproxy, void *ns)
if (atomic_read(&current->mm->mm_users) > 1)
return -EINVAL;
+ if (current->fs->users != 1)
+ return -EINVAL;
+
if (!ns_capable(user_ns, CAP_SYS_ADMIN))
return -EPERM;
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 81f2457811e..b48cd597145 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -457,11 +457,12 @@ static int worker_pool_assign_id(struct worker_pool *pool)
int ret;
mutex_lock(&worker_pool_idr_mutex);
- idr_pre_get(&worker_pool_idr, GFP_KERNEL);
- ret = idr_get_new(&worker_pool_idr, pool, &pool->id);
+ ret = idr_alloc(&worker_pool_idr, pool, 0, 0, GFP_KERNEL);
+ if (ret >= 0)
+ pool->id = ret;
mutex_unlock(&worker_pool_idr_mutex);
- return ret;
+ return ret < 0 ? ret : 0;
}
/*
@@ -3446,28 +3447,34 @@ static void wq_unbind_fn(struct work_struct *work)
spin_unlock_irq(&pool->lock);
mutex_unlock(&pool->assoc_mutex);
- }
- /*
- * Call schedule() so that we cross rq->lock and thus can guarantee
- * sched callbacks see the %WORKER_UNBOUND flag. This is necessary
- * as scheduler callbacks may be invoked from other cpus.
- */
- schedule();
+ /*
+ * Call schedule() so that we cross rq->lock and thus can
+ * guarantee sched callbacks see the %WORKER_UNBOUND flag.
+ * This is necessary as scheduler callbacks may be invoked
+ * from other cpus.
+ */
+ schedule();
- /*
- * Sched callbacks are disabled now. Zap nr_running. After this,
- * nr_running stays zero and need_more_worker() and keep_working()
- * are always true as long as the worklist is not empty. Pools on
- * @cpu now behave as unbound (in terms of concurrency management)
- * pools which are served by workers tied to the CPU.
- *
- * On return from this function, the current worker would trigger
- * unbound chain execution of pending work items if other workers
- * didn't already.
- */
- for_each_std_worker_pool(pool, cpu)
+ /*
+ * Sched callbacks are disabled now. Zap nr_running.
+ * After this, nr_running stays zero and need_more_worker()
+ * and keep_working() are always true as long as the
+ * worklist is not empty. This pool now behaves as an
+ * unbound (in terms of concurrency management) pool which
+ * are served by workers tied to the pool.
+ */
atomic_set(&pool->nr_running, 0);
+
+ /*
+ * With concurrency management just turned off, a busy
+ * worker blocking could lead to lengthy stalls. Kick off
+ * unbound chain execution of currently pending work items.
+ */
+ spin_lock_irq(&pool->lock);
+ wake_up_worker(pool);
+ spin_unlock_irq(&pool->lock);
+ }
}
/*