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-rw-r--r--kernel/Makefile4
-rw-r--r--kernel/audit_tree.c91
-rw-r--r--kernel/auditfilter.c14
-rw-r--r--kernel/cgroup_freezer.c19
-rw-r--r--kernel/cpuset.c12
-rw-r--r--kernel/exit.c9
-rw-r--r--kernel/fork.c11
-rw-r--r--kernel/hrtimer.c9
-rw-r--r--kernel/kprobes.c23
-rw-r--r--kernel/posix-cpu-timers.c7
-rw-r--r--kernel/power/main.c2
-rw-r--r--kernel/relay.c9
-rw-r--r--kernel/sched.c18
-rw-r--r--kernel/sched_debug.c5
-rw-r--r--kernel/sched_stats.h15
-rw-r--r--kernel/stop_machine.c5
16 files changed, 154 insertions, 99 deletions
diff --git a/kernel/Makefile b/kernel/Makefile
index 9a3ec66a9d8..19fad003b19 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -11,8 +11,6 @@ obj-y = sched.o fork.o exec_domain.o panic.o printk.o \
hrtimer.o rwsem.o nsproxy.o srcu.o semaphore.o \
notifier.o ksysfs.o pm_qos_params.o sched_clock.o
-CFLAGS_REMOVE_sched.o = -mno-spe
-
ifdef CONFIG_FUNCTION_TRACER
# Do not trace debug files and internal ftrace files
CFLAGS_REMOVE_lockdep.o = -pg
@@ -21,7 +19,7 @@ CFLAGS_REMOVE_mutex-debug.o = -pg
CFLAGS_REMOVE_rtmutex-debug.o = -pg
CFLAGS_REMOVE_cgroup-debug.o = -pg
CFLAGS_REMOVE_sched_clock.o = -pg
-CFLAGS_REMOVE_sched.o = -mno-spe -pg
+CFLAGS_REMOVE_sched.o = -pg
endif
obj-$(CONFIG_FREEZER) += freezer.o
diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c
index 8ba0e0d934f..8b509441f49 100644
--- a/kernel/audit_tree.c
+++ b/kernel/audit_tree.c
@@ -24,6 +24,7 @@ struct audit_chunk {
struct list_head trees; /* with root here */
int dead;
int count;
+ atomic_long_t refs;
struct rcu_head head;
struct node {
struct list_head list;
@@ -56,7 +57,8 @@ static LIST_HEAD(prune_list);
* tree is refcounted; one reference for "some rules on rules_list refer to
* it", one for each chunk with pointer to it.
*
- * chunk is refcounted by embedded inotify_watch.
+ * chunk is refcounted by embedded inotify_watch + .refs (non-zero refcount
+ * of watch contributes 1 to .refs).
*
* node.index allows to get from node.list to containing chunk.
* MSB of that sucker is stolen to mark taggings that we might have to
@@ -121,6 +123,7 @@ static struct audit_chunk *alloc_chunk(int count)
INIT_LIST_HEAD(&chunk->hash);
INIT_LIST_HEAD(&chunk->trees);
chunk->count = count;
+ atomic_long_set(&chunk->refs, 1);
for (i = 0; i < count; i++) {
INIT_LIST_HEAD(&chunk->owners[i].list);
chunk->owners[i].index = i;
@@ -129,9 +132,8 @@ static struct audit_chunk *alloc_chunk(int count)
return chunk;
}
-static void __free_chunk(struct rcu_head *rcu)
+static void free_chunk(struct audit_chunk *chunk)
{
- struct audit_chunk *chunk = container_of(rcu, struct audit_chunk, head);
int i;
for (i = 0; i < chunk->count; i++) {
@@ -141,14 +143,16 @@ static void __free_chunk(struct rcu_head *rcu)
kfree(chunk);
}
-static inline void free_chunk(struct audit_chunk *chunk)
+void audit_put_chunk(struct audit_chunk *chunk)
{
- call_rcu(&chunk->head, __free_chunk);
+ if (atomic_long_dec_and_test(&chunk->refs))
+ free_chunk(chunk);
}
-void audit_put_chunk(struct audit_chunk *chunk)
+static void __put_chunk(struct rcu_head *rcu)
{
- put_inotify_watch(&chunk->watch);
+ struct audit_chunk *chunk = container_of(rcu, struct audit_chunk, head);
+ audit_put_chunk(chunk);
}
enum {HASH_SIZE = 128};
@@ -176,7 +180,7 @@ struct audit_chunk *audit_tree_lookup(const struct inode *inode)
list_for_each_entry_rcu(p, list, hash) {
if (p->watch.inode == inode) {
- get_inotify_watch(&p->watch);
+ atomic_long_inc(&p->refs);
return p;
}
}
@@ -194,17 +198,49 @@ int audit_tree_match(struct audit_chunk *chunk, struct audit_tree *tree)
/* tagging and untagging inodes with trees */
-static void untag_chunk(struct audit_chunk *chunk, struct node *p)
+static struct audit_chunk *find_chunk(struct node *p)
+{
+ int index = p->index & ~(1U<<31);
+ p -= index;
+ return container_of(p, struct audit_chunk, owners[0]);
+}
+
+static void untag_chunk(struct node *p)
{
+ struct audit_chunk *chunk = find_chunk(p);
struct audit_chunk *new;
struct audit_tree *owner;
int size = chunk->count - 1;
int i, j;
+ if (!pin_inotify_watch(&chunk->watch)) {
+ /*
+ * Filesystem is shutting down; all watches are getting
+ * evicted, just take it off the node list for this
+ * tree and let the eviction logics take care of the
+ * rest.
+ */
+ owner = p->owner;
+ if (owner->root == chunk) {
+ list_del_init(&owner->same_root);
+ owner->root = NULL;
+ }
+ list_del_init(&p->list);
+ p->owner = NULL;
+ put_tree(owner);
+ return;
+ }
+
+ spin_unlock(&hash_lock);
+
+ /*
+ * pin_inotify_watch() succeeded, so the watch won't go away
+ * from under us.
+ */
mutex_lock(&chunk->watch.inode->inotify_mutex);
if (chunk->dead) {
mutex_unlock(&chunk->watch.inode->inotify_mutex);
- return;
+ goto out;
}
owner = p->owner;
@@ -221,7 +257,7 @@ static void untag_chunk(struct audit_chunk *chunk, struct node *p)
inotify_evict_watch(&chunk->watch);
mutex_unlock(&chunk->watch.inode->inotify_mutex);
put_inotify_watch(&chunk->watch);
- return;
+ goto out;
}
new = alloc_chunk(size);
@@ -263,7 +299,7 @@ static void untag_chunk(struct audit_chunk *chunk, struct node *p)
inotify_evict_watch(&chunk->watch);
mutex_unlock(&chunk->watch.inode->inotify_mutex);
put_inotify_watch(&chunk->watch);
- return;
+ goto out;
Fallback:
// do the best we can
@@ -277,6 +313,9 @@ Fallback:
put_tree(owner);
spin_unlock(&hash_lock);
mutex_unlock(&chunk->watch.inode->inotify_mutex);
+out:
+ unpin_inotify_watch(&chunk->watch);
+ spin_lock(&hash_lock);
}
static int create_chunk(struct inode *inode, struct audit_tree *tree)
@@ -387,13 +426,6 @@ static int tag_chunk(struct inode *inode, struct audit_tree *tree)
return 0;
}
-static struct audit_chunk *find_chunk(struct node *p)
-{
- int index = p->index & ~(1U<<31);
- p -= index;
- return container_of(p, struct audit_chunk, owners[0]);
-}
-
static void kill_rules(struct audit_tree *tree)
{
struct audit_krule *rule, *next;
@@ -431,17 +463,10 @@ static void prune_one(struct audit_tree *victim)
spin_lock(&hash_lock);
while (!list_empty(&victim->chunks)) {
struct node *p;
- struct audit_chunk *chunk;
p = list_entry(victim->chunks.next, struct node, list);
- chunk = find_chunk(p);
- get_inotify_watch(&chunk->watch);
- spin_unlock(&hash_lock);
-
- untag_chunk(chunk, p);
- put_inotify_watch(&chunk->watch);
- spin_lock(&hash_lock);
+ untag_chunk(p);
}
spin_unlock(&hash_lock);
put_tree(victim);
@@ -469,7 +494,6 @@ static void trim_marked(struct audit_tree *tree)
while (!list_empty(&tree->chunks)) {
struct node *node;
- struct audit_chunk *chunk;
node = list_entry(tree->chunks.next, struct node, list);
@@ -477,14 +501,7 @@ static void trim_marked(struct audit_tree *tree)
if (!(node->index & (1U<<31)))
break;
- chunk = find_chunk(node);
- get_inotify_watch(&chunk->watch);
- spin_unlock(&hash_lock);
-
- untag_chunk(chunk, node);
-
- put_inotify_watch(&chunk->watch);
- spin_lock(&hash_lock);
+ untag_chunk(node);
}
if (!tree->root && !tree->goner) {
tree->goner = 1;
@@ -878,7 +895,7 @@ static void handle_event(struct inotify_watch *watch, u32 wd, u32 mask,
static void destroy_watch(struct inotify_watch *watch)
{
struct audit_chunk *chunk = container_of(watch, struct audit_chunk, watch);
- free_chunk(chunk);
+ call_rcu(&chunk->head, __put_chunk);
}
static const struct inotify_operations rtree_inotify_ops = {
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index b7d354e2b0e..9fd85a4640a 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -1094,8 +1094,8 @@ static void audit_inotify_unregister(struct list_head *in_list)
list_for_each_entry_safe(p, n, in_list, ilist) {
list_del(&p->ilist);
inotify_rm_watch(audit_ih, &p->wdata);
- /* the put matching the get in audit_do_del_rule() */
- put_inotify_watch(&p->wdata);
+ /* the unpin matching the pin in audit_do_del_rule() */
+ unpin_inotify_watch(&p->wdata);
}
}
@@ -1389,9 +1389,13 @@ static inline int audit_del_rule(struct audit_entry *entry,
/* Put parent on the inotify un-registration
* list. Grab a reference before releasing
* audit_filter_mutex, to be released in
- * audit_inotify_unregister(). */
- list_add(&parent->ilist, &inotify_list);
- get_inotify_watch(&parent->wdata);
+ * audit_inotify_unregister().
+ * If filesystem is going away, just leave
+ * the sucker alone, eviction will take
+ * care of it.
+ */
+ if (pin_inotify_watch(&parent->wdata))
+ list_add(&parent->ilist, &inotify_list);
}
}
}
diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c
index 7fa476f01d0..fb249e2bcad 100644
--- a/kernel/cgroup_freezer.c
+++ b/kernel/cgroup_freezer.c
@@ -184,9 +184,20 @@ static void freezer_fork(struct cgroup_subsys *ss, struct task_struct *task)
{
struct freezer *freezer;
- task_lock(task);
+ /*
+ * No lock is needed, since the task isn't on tasklist yet,
+ * so it can't be moved to another cgroup, which means the
+ * freezer won't be removed and will be valid during this
+ * function call.
+ */
freezer = task_freezer(task);
- task_unlock(task);
+
+ /*
+ * The root cgroup is non-freezable, so we can skip the
+ * following check.
+ */
+ if (!freezer->css.cgroup->parent)
+ return;
spin_lock_irq(&freezer->lock);
BUG_ON(freezer->state == CGROUP_FROZEN);
@@ -331,7 +342,7 @@ static int freezer_write(struct cgroup *cgroup,
else if (strcmp(buffer, freezer_state_strs[CGROUP_FROZEN]) == 0)
goal_state = CGROUP_FROZEN;
else
- return -EIO;
+ return -EINVAL;
if (!cgroup_lock_live_group(cgroup))
return -ENODEV;
@@ -350,6 +361,8 @@ static struct cftype files[] = {
static int freezer_populate(struct cgroup_subsys *ss, struct cgroup *cgroup)
{
+ if (!cgroup->parent)
+ return 0;
return cgroup_add_files(cgroup, ss, files, ARRAY_SIZE(files));
}
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 3e00526f52e..81fc6791a29 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -587,7 +587,6 @@ static int generate_sched_domains(cpumask_t **domains,
int ndoms; /* number of sched domains in result */
int nslot; /* next empty doms[] cpumask_t slot */
- ndoms = 0;
doms = NULL;
dattr = NULL;
csa = NULL;
@@ -674,10 +673,8 @@ restart:
* Convert <csn, csa> to <ndoms, doms> and populate cpu masks.
*/
doms = kmalloc(ndoms * sizeof(cpumask_t), GFP_KERNEL);
- if (!doms) {
- ndoms = 0;
+ if (!doms)
goto done;
- }
/*
* The rest of the code, including the scheduler, can deal with
@@ -732,6 +729,13 @@ restart:
done:
kfree(csa);
+ /*
+ * Fallback to the default domain if kmalloc() failed.
+ * See comments in partition_sched_domains().
+ */
+ if (doms == NULL)
+ ndoms = 1;
+
*domains = doms;
*attributes = dattr;
return ndoms;
diff --git a/kernel/exit.c b/kernel/exit.c
index ae2b92be5fa..2d8be7ebb0f 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -40,7 +40,6 @@
#include <linux/cn_proc.h>
#include <linux/mutex.h>
#include <linux/futex.h>
-#include <linux/compat.h>
#include <linux/pipe_fs_i.h>
#include <linux/audit.h> /* for audit_free() */
#include <linux/resource.h>
@@ -1059,14 +1058,6 @@ NORET_TYPE void do_exit(long code)
exit_itimers(tsk->signal);
}
acct_collect(code, group_dead);
-#ifdef CONFIG_FUTEX
- if (unlikely(tsk->robust_list))
- exit_robust_list(tsk);
-#ifdef CONFIG_COMPAT
- if (unlikely(tsk->compat_robust_list))
- compat_exit_robust_list(tsk);
-#endif
-#endif
if (group_dead)
tty_audit_exit();
if (unlikely(tsk->audit_context))
diff --git a/kernel/fork.c b/kernel/fork.c
index f6083561dfe..2a372a0e206 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -40,6 +40,7 @@
#include <linux/jiffies.h>
#include <linux/tracehook.h>
#include <linux/futex.h>
+#include <linux/compat.h>
#include <linux/task_io_accounting_ops.h>
#include <linux/rcupdate.h>
#include <linux/ptrace.h>
@@ -519,6 +520,16 @@ void mm_release(struct task_struct *tsk, struct mm_struct *mm)
{
struct completion *vfork_done = tsk->vfork_done;
+ /* Get rid of any futexes when releasing the mm */
+#ifdef CONFIG_FUTEX
+ if (unlikely(tsk->robust_list))
+ exit_robust_list(tsk);
+#ifdef CONFIG_COMPAT
+ if (unlikely(tsk->compat_robust_list))
+ compat_exit_robust_list(tsk);
+#endif
+#endif
+
/* Get rid of any cached register state */
deactivate_mm(tsk, mm);
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 95d3949f2ae..47e63349d1b 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -664,14 +664,6 @@ static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
/* Timer is expired, act upon the callback mode */
switch(timer->cb_mode) {
- case HRTIMER_CB_IRQSAFE_NO_RESTART:
- debug_hrtimer_deactivate(timer);
- /*
- * We can call the callback from here. No restart
- * happens, so no danger of recursion
- */
- BUG_ON(timer->function(timer) != HRTIMER_NORESTART);
- return 1;
case HRTIMER_CB_IRQSAFE_PERCPU:
case HRTIMER_CB_IRQSAFE_UNLOCKED:
/*
@@ -683,7 +675,6 @@ static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
*/
debug_hrtimer_deactivate(timer);
return 1;
- case HRTIMER_CB_IRQSAFE:
case HRTIMER_CB_SOFTIRQ:
/*
* Move everything else into the softirq pending list !
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 8b57a2597f2..9f8a3f25259 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -72,7 +72,7 @@ static bool kprobe_enabled;
DEFINE_MUTEX(kprobe_mutex); /* Protects kprobe_table */
static DEFINE_PER_CPU(struct kprobe *, kprobe_instance) = NULL;
static struct {
- spinlock_t lock ____cacheline_aligned;
+ spinlock_t lock ____cacheline_aligned_in_smp;
} kretprobe_table_locks[KPROBE_TABLE_SIZE];
static spinlock_t *kretprobe_table_lock_ptr(unsigned long hash)
@@ -613,30 +613,37 @@ static int __kprobes __register_kprobe(struct kprobe *p,
return -EINVAL;
p->addr = addr;
- if (!kernel_text_address((unsigned long) p->addr) ||
- in_kprobes_functions((unsigned long) p->addr))
+ preempt_disable();
+ if (!__kernel_text_address((unsigned long) p->addr) ||
+ in_kprobes_functions((unsigned long) p->addr)) {
+ preempt_enable();
return -EINVAL;
+ }
p->mod_refcounted = 0;
/*
* Check if are we probing a module.
*/
- probed_mod = module_text_address((unsigned long) p->addr);
+ probed_mod = __module_text_address((unsigned long) p->addr);
if (probed_mod) {
- struct module *calling_mod = module_text_address(called_from);
+ struct module *calling_mod;
+ calling_mod = __module_text_address(called_from);
/*
* We must allow modules to probe themself and in this case
* avoid incrementing the module refcount, so as to allow
* unloading of self probing modules.
*/
if (calling_mod && calling_mod != probed_mod) {
- if (unlikely(!try_module_get(probed_mod)))
+ if (unlikely(!try_module_get(probed_mod))) {
+ preempt_enable();
return -EINVAL;
+ }
p->mod_refcounted = 1;
} else
probed_mod = NULL;
}
+ preempt_enable();
p->nmissed = 0;
INIT_LIST_HEAD(&p->list);
@@ -718,6 +725,10 @@ static void __kprobes __unregister_kprobe_bottom(struct kprobe *p)
struct kprobe *old_p;
if (p->mod_refcounted) {
+ /*
+ * Since we've already incremented refcount,
+ * we don't need to disable preemption.
+ */
mod = module_text_address((unsigned long)p->addr);
if (mod)
module_put(mod);
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index 153dcb2639c..895337b16a2 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -1308,9 +1308,10 @@ static inline int task_cputime_expired(const struct task_cputime *sample,
*/
static inline int fastpath_timer_check(struct task_struct *tsk)
{
- struct signal_struct *sig = tsk->signal;
+ struct signal_struct *sig;
- if (unlikely(!sig))
+ /* tsk == current, ensure it is safe to use ->signal/sighand */
+ if (unlikely(tsk->exit_state))
return 0;
if (!task_cputime_zero(&tsk->cputime_expires)) {
@@ -1323,6 +1324,8 @@ static inline int fastpath_timer_check(struct task_struct *tsk)
if (task_cputime_expired(&task_sample, &tsk->cputime_expires))
return 1;
}
+
+ sig = tsk->signal;
if (!task_cputime_zero(&sig->cputime_expires)) {
struct task_cputime group_sample;
diff --git a/kernel/power/main.c b/kernel/power/main.c
index 19122cf6d82..b8f7ce9473e 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -174,7 +174,7 @@ static void suspend_test_finish(const char *label)
* has some performance issues. The stack dump of a WARN_ON
* is more likely to get the right attention than a printk...
*/
- WARN_ON(msec > (TEST_SUSPEND_SECONDS * 1000));
+ WARN(msec > (TEST_SUSPEND_SECONDS * 1000), "Component: %s\n", label);
}
#else
diff --git a/kernel/relay.c b/kernel/relay.c
index 8d13a7855c0..32b0befdcb6 100644
--- a/kernel/relay.c
+++ b/kernel/relay.c
@@ -400,7 +400,7 @@ void relay_reset(struct rchan *chan)
}
mutex_lock(&relay_channels_mutex);
- for_each_online_cpu(i)
+ for_each_possible_cpu(i)
if (chan->buf[i])
__relay_reset(chan->buf[i], 0);
mutex_unlock(&relay_channels_mutex);
@@ -611,10 +611,9 @@ struct rchan *relay_open(const char *base_filename,
return chan;
free_bufs:
- for_each_online_cpu(i) {
- if (!chan->buf[i])
- break;
- relay_close_buf(chan->buf[i]);
+ for_each_possible_cpu(i) {
+ if (chan->buf[i])
+ relay_close_buf(chan->buf[i]);
}
kref_put(&chan->kref, relay_destroy_channel);
diff --git a/kernel/sched.c b/kernel/sched.c
index 50a21f96467..9b1e79371c2 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -1456,6 +1456,8 @@ static unsigned long cpu_avg_load_per_task(int cpu)
if (rq->nr_running)
rq->avg_load_per_task = rq->load.weight / rq->nr_running;
+ else
+ rq->avg_load_per_task = 0;
return rq->avg_load_per_task;
}
@@ -5868,6 +5870,8 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu)
struct rq *rq = cpu_rq(cpu);
unsigned long flags;
+ spin_lock_irqsave(&rq->lock, flags);
+
__sched_fork(idle);
idle->se.exec_start = sched_clock();
@@ -5875,7 +5879,6 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu)
idle->cpus_allowed = cpumask_of_cpu(cpu);
__set_task_cpu(idle, cpu);
- spin_lock_irqsave(&rq->lock, flags);
rq->curr = rq->idle = idle;
#if defined(CONFIG_SMP) && defined(__ARCH_WANT_UNLOCKED_CTXSW)
idle->oncpu = 1;
@@ -7786,13 +7789,14 @@ static int dattrs_equal(struct sched_domain_attr *cur, int idx_cur,
*
* The passed in 'doms_new' should be kmalloc'd. This routine takes
* ownership of it and will kfree it when done with it. If the caller
- * failed the kmalloc call, then it can pass in doms_new == NULL,
- * and partition_sched_domains() will fallback to the single partition
- * 'fallback_doms', it also forces the domains to be rebuilt.
+ * failed the kmalloc call, then it can pass in doms_new == NULL &&
+ * ndoms_new == 1, and partition_sched_domains() will fallback to
+ * the single partition 'fallback_doms', it also forces the domains
+ * to be rebuilt.
*
- * If doms_new==NULL it will be replaced with cpu_online_map.
- * ndoms_new==0 is a special case for destroying existing domains.
- * It will not create the default domain.
+ * If doms_new == NULL it will be replaced with cpu_online_map.
+ * ndoms_new == 0 is a special case for destroying existing domains,
+ * and it will not create the default domain.
*
* Call with hotplug lock held
*/
diff --git a/kernel/sched_debug.c b/kernel/sched_debug.c
index 48ecc51e770..26ed8e3d1c1 100644
--- a/kernel/sched_debug.c
+++ b/kernel/sched_debug.c
@@ -423,10 +423,11 @@ void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
#undef __P
{
+ unsigned int this_cpu = raw_smp_processor_id();
u64 t0, t1;
- t0 = sched_clock();
- t1 = sched_clock();
+ t0 = cpu_clock(this_cpu);
+ t1 = cpu_clock(this_cpu);
SEQ_printf(m, "%-35s:%21Ld\n",
"clock-delta", (long long)(t1-t0));
}
diff --git a/kernel/sched_stats.h b/kernel/sched_stats.h
index ee71bec1da6..7dbf72a2b02 100644
--- a/kernel/sched_stats.h
+++ b/kernel/sched_stats.h
@@ -298,9 +298,11 @@ static inline void account_group_user_time(struct task_struct *tsk,
{
struct signal_struct *sig;
- sig = tsk->signal;
- if (unlikely(!sig))
+ /* tsk == current, ensure it is safe to use ->signal */
+ if (unlikely(tsk->exit_state))
return;
+
+ sig = tsk->signal;
if (sig->cputime.totals) {
struct task_cputime *times;
@@ -325,9 +327,11 @@ static inline void account_group_system_time(struct task_struct *tsk,
{
struct signal_struct *sig;
- sig = tsk->signal;
- if (unlikely(!sig))
+ /* tsk == current, ensure it is safe to use ->signal */
+ if (unlikely(tsk->exit_state))
return;
+
+ sig = tsk->signal;
if (sig->cputime.totals) {
struct task_cputime *times;
@@ -353,8 +357,11 @@ static inline void account_group_exec_runtime(struct task_struct *tsk,
struct signal_struct *sig;
sig = tsk->signal;
+ /* see __exit_signal()->task_rq_unlock_wait() */
+ barrier();
if (unlikely(!sig))
return;
+
if (sig->cputime.totals) {
struct task_cputime *times;
diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c
index 9bc4c00872c..24e8ceacc38 100644
--- a/kernel/stop_machine.c
+++ b/kernel/stop_machine.c
@@ -112,7 +112,7 @@ static int chill(void *unused)
int __stop_machine(int (*fn)(void *), void *data, const cpumask_t *cpus)
{
struct work_struct *sm_work;
- int i;
+ int i, ret;
/* Set up initial state. */
mutex_lock(&lock);
@@ -137,8 +137,9 @@ int __stop_machine(int (*fn)(void *), void *data, const cpumask_t *cpus)
/* This will release the thread on our CPU. */
put_cpu();
flush_workqueue(stop_machine_wq);
+ ret = active.fnret;
mutex_unlock(&lock);
- return active.fnret;
+ return ret;
}
int stop_machine(int (*fn)(void *), void *data, const cpumask_t *cpus)
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-18 19:57:11 +0000