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-rw-r--r--kernel/cgroup.c401
-rw-r--r--kernel/cgroup_freezer.c16
-rw-r--r--kernel/cpuset.c105
-rw-r--r--kernel/events/core.c13
-rw-r--r--kernel/exit.c3
-rw-r--r--kernel/fork.c15
-rw-r--r--kernel/jump_label.c2
-rw-r--r--kernel/power/snapshot.c6
-rw-r--r--kernel/res_counter.c3
-rw-r--r--kernel/sched/core.c31
-rw-r--r--kernel/signal.c74
-rw-r--r--kernel/workqueue.c32
12 files changed, 427 insertions, 274 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 7cab65f83f1..a5d3b5325f7 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -63,7 +63,24 @@
#include <linux/atomic.h>
+/*
+ * cgroup_mutex is the master lock. Any modification to cgroup or its
+ * hierarchy must be performed while holding it.
+ *
+ * cgroup_root_mutex nests inside cgroup_mutex and should be held to modify
+ * cgroupfs_root of any cgroup hierarchy - subsys list, flags,
+ * release_agent_path and so on. Modifying requires both cgroup_mutex and
+ * cgroup_root_mutex. Readers can acquire either of the two. This is to
+ * break the following locking order cycle.
+ *
+ * A. cgroup_mutex -> cred_guard_mutex -> s_type->i_mutex_key -> namespace_sem
+ * B. namespace_sem -> cgroup_mutex
+ *
+ * B happens only through cgroup_show_options() and using cgroup_root_mutex
+ * breaks it.
+ */
static DEFINE_MUTEX(cgroup_mutex);
+static DEFINE_MUTEX(cgroup_root_mutex);
/*
* Generate an array of cgroup subsystem pointers. At boot time, this is
@@ -921,7 +938,7 @@ static void cgroup_d_remove_dir(struct dentry *dentry)
*
* CGRP_WAIT_ON_RMDIR flag is set under cgroup's inode->i_mutex;
*/
-DECLARE_WAIT_QUEUE_HEAD(cgroup_rmdir_waitq);
+static DECLARE_WAIT_QUEUE_HEAD(cgroup_rmdir_waitq);
static void cgroup_wakeup_rmdir_waiter(struct cgroup *cgrp)
{
@@ -953,6 +970,7 @@ static int rebind_subsystems(struct cgroupfs_root *root,
int i;
BUG_ON(!mutex_is_locked(&cgroup_mutex));
+ BUG_ON(!mutex_is_locked(&cgroup_root_mutex));
removed_bits = root->actual_subsys_bits & ~final_bits;
added_bits = final_bits & ~root->actual_subsys_bits;
@@ -1043,7 +1061,7 @@ static int cgroup_show_options(struct seq_file *seq, struct dentry *dentry)
struct cgroupfs_root *root = dentry->d_sb->s_fs_info;
struct cgroup_subsys *ss;
- mutex_lock(&cgroup_mutex);
+ mutex_lock(&cgroup_root_mutex);
for_each_subsys(root, ss)
seq_printf(seq, ",%s", ss->name);
if (test_bit(ROOT_NOPREFIX, &root->flags))
@@ -1054,7 +1072,7 @@ static int cgroup_show_options(struct seq_file *seq, struct dentry *dentry)
seq_puts(seq, ",clone_children");
if (strlen(root->name))
seq_printf(seq, ",name=%s", root->name);
- mutex_unlock(&cgroup_mutex);
+ mutex_unlock(&cgroup_root_mutex);
return 0;
}
@@ -1175,10 +1193,10 @@ static int parse_cgroupfs_options(char *data, struct cgroup_sb_opts *opts)
/*
* If the 'all' option was specified select all the subsystems,
- * otherwise 'all, 'none' and a subsystem name options were not
- * specified, let's default to 'all'
+ * otherwise if 'none', 'name=' and a subsystem name options
+ * were not specified, let's default to 'all'
*/
- if (all_ss || (!all_ss && !one_ss && !opts->none)) {
+ if (all_ss || (!one_ss && !opts->none && !opts->name)) {
for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
struct cgroup_subsys *ss = subsys[i];
if (ss == NULL)
@@ -1269,6 +1287,7 @@ static int cgroup_remount(struct super_block *sb, int *flags, char *data)
mutex_lock(&cgrp->dentry->d_inode->i_mutex);
mutex_lock(&cgroup_mutex);
+ mutex_lock(&cgroup_root_mutex);
/* See what subsystems are wanted */
ret = parse_cgroupfs_options(data, &opts);
@@ -1297,6 +1316,7 @@ static int cgroup_remount(struct super_block *sb, int *flags, char *data)
out_unlock:
kfree(opts.release_agent);
kfree(opts.name);
+ mutex_unlock(&cgroup_root_mutex);
mutex_unlock(&cgroup_mutex);
mutex_unlock(&cgrp->dentry->d_inode->i_mutex);
return ret;
@@ -1481,6 +1501,7 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type,
int ret = 0;
struct super_block *sb;
struct cgroupfs_root *new_root;
+ struct inode *inode;
/* First find the desired set of subsystems */
mutex_lock(&cgroup_mutex);
@@ -1514,7 +1535,6 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type,
/* We used the new root structure, so this is a new hierarchy */
struct list_head tmp_cg_links;
struct cgroup *root_cgrp = &root->top_cgroup;
- struct inode *inode;
struct cgroupfs_root *existing_root;
const struct cred *cred;
int i;
@@ -1528,18 +1548,14 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type,
mutex_lock(&inode->i_mutex);
mutex_lock(&cgroup_mutex);
+ mutex_lock(&cgroup_root_mutex);
- if (strlen(root->name)) {
- /* Check for name clashes with existing mounts */
- for_each_active_root(existing_root) {
- if (!strcmp(existing_root->name, root->name)) {
- ret = -EBUSY;
- mutex_unlock(&cgroup_mutex);
- mutex_unlock(&inode->i_mutex);
- goto drop_new_super;
- }
- }
- }
+ /* Check for name clashes with existing mounts */
+ ret = -EBUSY;
+ if (strlen(root->name))
+ for_each_active_root(existing_root)
+ if (!strcmp(existing_root->name, root->name))
+ goto unlock_drop;
/*
* We're accessing css_set_count without locking
@@ -1549,18 +1565,13 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type,
* have some link structures left over
*/
ret = allocate_cg_links(css_set_count, &tmp_cg_links);
- if (ret) {
- mutex_unlock(&cgroup_mutex);
- mutex_unlock(&inode->i_mutex);
- goto drop_new_super;
- }
+ if (ret)
+ goto unlock_drop;
ret = rebind_subsystems(root, root->subsys_bits);
if (ret == -EBUSY) {
- mutex_unlock(&cgroup_mutex);
- mutex_unlock(&inode->i_mutex);
free_cg_links(&tmp_cg_links);
- goto drop_new_super;
+ goto unlock_drop;
}
/*
* There must be no failure case after here, since rebinding
@@ -1599,6 +1610,7 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type,
cred = override_creds(&init_cred);
cgroup_populate_dir(root_cgrp);
revert_creds(cred);
+ mutex_unlock(&cgroup_root_mutex);
mutex_unlock(&cgroup_mutex);
mutex_unlock(&inode->i_mutex);
} else {
@@ -1615,6 +1627,10 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type,
kfree(opts.name);
return dget(sb->s_root);
+ unlock_drop:
+ mutex_unlock(&cgroup_root_mutex);
+ mutex_unlock(&cgroup_mutex);
+ mutex_unlock(&inode->i_mutex);
drop_new_super:
deactivate_locked_super(sb);
drop_modules:
@@ -1639,6 +1655,7 @@ static void cgroup_kill_sb(struct super_block *sb) {
BUG_ON(!list_empty(&cgrp->sibling));
mutex_lock(&cgroup_mutex);
+ mutex_lock(&cgroup_root_mutex);
/* Rebind all subsystems back to the default hierarchy */
ret = rebind_subsystems(root, 0);
@@ -1664,6 +1681,7 @@ static void cgroup_kill_sb(struct super_block *sb) {
root_count--;
}
+ mutex_unlock(&cgroup_root_mutex);
mutex_unlock(&cgroup_mutex);
kill_litter_super(sb);
@@ -1740,11 +1758,90 @@ int cgroup_path(const struct cgroup *cgrp, char *buf, int buflen)
EXPORT_SYMBOL_GPL(cgroup_path);
/*
+ * Control Group taskset
+ */
+struct task_and_cgroup {
+ struct task_struct *task;
+ struct cgroup *cgrp;
+};
+
+struct cgroup_taskset {
+ struct task_and_cgroup single;
+ struct flex_array *tc_array;
+ int tc_array_len;
+ int idx;
+ struct cgroup *cur_cgrp;
+};
+
+/**
+ * cgroup_taskset_first - reset taskset and return the first task
+ * @tset: taskset of interest
+ *
+ * @tset iteration is initialized and the first task is returned.
+ */
+struct task_struct *cgroup_taskset_first(struct cgroup_taskset *tset)
+{
+ if (tset->tc_array) {
+ tset->idx = 0;
+ return cgroup_taskset_next(tset);
+ } else {
+ tset->cur_cgrp = tset->single.cgrp;
+ return tset->single.task;
+ }
+}
+EXPORT_SYMBOL_GPL(cgroup_taskset_first);
+
+/**
+ * cgroup_taskset_next - iterate to the next task in taskset
+ * @tset: taskset of interest
+ *
+ * Return the next task in @tset. Iteration must have been initialized
+ * with cgroup_taskset_first().
+ */
+struct task_struct *cgroup_taskset_next(struct cgroup_taskset *tset)
+{
+ struct task_and_cgroup *tc;
+
+ if (!tset->tc_array || tset->idx >= tset->tc_array_len)
+ return NULL;
+
+ tc = flex_array_get(tset->tc_array, tset->idx++);
+ tset->cur_cgrp = tc->cgrp;
+ return tc->task;
+}
+EXPORT_SYMBOL_GPL(cgroup_taskset_next);
+
+/**
+ * cgroup_taskset_cur_cgroup - return the matching cgroup for the current task
+ * @tset: taskset of interest
+ *
+ * Return the cgroup for the current (last returned) task of @tset. This
+ * function must be preceded by either cgroup_taskset_first() or
+ * cgroup_taskset_next().
+ */
+struct cgroup *cgroup_taskset_cur_cgroup(struct cgroup_taskset *tset)
+{
+ return tset->cur_cgrp;
+}
+EXPORT_SYMBOL_GPL(cgroup_taskset_cur_cgroup);
+
+/**
+ * cgroup_taskset_size - return the number of tasks in taskset
+ * @tset: taskset of interest
+ */
+int cgroup_taskset_size(struct cgroup_taskset *tset)
+{
+ return tset->tc_array ? tset->tc_array_len : 1;
+}
+EXPORT_SYMBOL_GPL(cgroup_taskset_size);
+
+
+/*
* cgroup_task_migrate - move a task from one cgroup to another.
*
* 'guarantee' is set if the caller promises that a new css_set for the task
* will already exist. If not set, this function might sleep, and can fail with
- * -ENOMEM. Otherwise, it can only fail with -ESRCH.
+ * -ENOMEM. Must be called with cgroup_mutex and threadgroup locked.
*/
static int cgroup_task_migrate(struct cgroup *cgrp, struct cgroup *oldcgrp,
struct task_struct *tsk, bool guarantee)
@@ -1753,14 +1850,12 @@ static int cgroup_task_migrate(struct cgroup *cgrp, struct cgroup *oldcgrp,
struct css_set *newcg;
/*
- * get old css_set. we need to take task_lock and refcount it, because
- * an exiting task can change its css_set to init_css_set and drop its
- * old one without taking cgroup_mutex.
+ * We are synchronized through threadgroup_lock() against PF_EXITING
+ * setting such that we can't race against cgroup_exit() changing the
+ * css_set to init_css_set and dropping the old one.
*/
- task_lock(tsk);
+ WARN_ON_ONCE(tsk->flags & PF_EXITING);
oldcg = tsk->cgroups;
- get_css_set(oldcg);
- task_unlock(tsk);
/* locate or allocate a new css_set for this task. */
if (guarantee) {
@@ -1775,20 +1870,11 @@ static int cgroup_task_migrate(struct cgroup *cgrp, struct cgroup *oldcgrp,
might_sleep();
/* find_css_set will give us newcg already referenced. */
newcg = find_css_set(oldcg, cgrp);
- if (!newcg) {
- put_css_set(oldcg);
+ if (!newcg)
return -ENOMEM;
- }
}
- put_css_set(oldcg);
- /* if PF_EXITING is set, the tsk->cgroups pointer is no longer safe. */
task_lock(tsk);
- if (tsk->flags & PF_EXITING) {
- task_unlock(tsk);
- put_css_set(newcg);
- return -ESRCH;
- }
rcu_assign_pointer(tsk->cgroups, newcg);
task_unlock(tsk);
@@ -1814,8 +1900,8 @@ static int cgroup_task_migrate(struct cgroup *cgrp, struct cgroup *oldcgrp,
* @cgrp: the cgroup the task is attaching to
* @tsk: the task to be attached
*
- * Call holding cgroup_mutex. May take task_lock of
- * the task 'tsk' during call.
+ * Call with cgroup_mutex and threadgroup locked. May take task_lock of
+ * @tsk during call.
*/
int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk)
{
@@ -1823,15 +1909,23 @@ int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk)
struct cgroup_subsys *ss, *failed_ss = NULL;
struct cgroup *oldcgrp;
struct cgroupfs_root *root = cgrp->root;
+ struct cgroup_taskset tset = { };
+
+ /* @tsk either already exited or can't exit until the end */
+ if (tsk->flags & PF_EXITING)
+ return -ESRCH;
/* Nothing to do if the task is already in that cgroup */
oldcgrp = task_cgroup_from_root(tsk, root);
if (cgrp == oldcgrp)
return 0;
+ tset.single.task = tsk;
+ tset.single.cgrp = oldcgrp;
+
for_each_subsys(root, ss) {
if (ss->can_attach) {
- retval = ss->can_attach(ss, cgrp, tsk);
+ retval = ss->can_attach(ss, cgrp, &tset);
if (retval) {
/*
* Remember on which subsystem the can_attach()
@@ -1843,13 +1937,6 @@ int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk)
goto out;
}
}
- if (ss->can_attach_task) {
- retval = ss->can_attach_task(cgrp, tsk);
- if (retval) {
- failed_ss = ss;
- goto out;
- }
- }
}
retval = cgroup_task_migrate(cgrp, oldcgrp, tsk, false);
@@ -1857,12 +1944,8 @@ int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk)
goto out;
for_each_subsys(root, ss) {
- if (ss->pre_attach)
- ss->pre_attach(cgrp);
- if (ss->attach_task)
- ss->attach_task(cgrp, tsk);
if (ss->attach)
- ss->attach(ss, cgrp, oldcgrp, tsk);
+ ss->attach(ss, cgrp, &tset);
}
synchronize_rcu();
@@ -1884,7 +1967,7 @@ out:
*/
break;
if (ss->cancel_attach)
- ss->cancel_attach(ss, cgrp, tsk);
+ ss->cancel_attach(ss, cgrp, &tset);
}
}
return retval;
@@ -1935,23 +2018,17 @@ static bool css_set_check_fetched(struct cgroup *cgrp,
read_lock(&css_set_lock);
newcg = find_existing_css_set(cg, cgrp, template);
- if (newcg)
- get_css_set(newcg);
read_unlock(&css_set_lock);
/* doesn't exist at all? */
if (!newcg)
return false;
/* see if it's already in the list */
- list_for_each_entry(cg_entry, newcg_list, links) {
- if (cg_entry->cg == newcg) {
- put_css_set(newcg);
+ list_for_each_entry(cg_entry, newcg_list, links)
+ if (cg_entry->cg == newcg)
return true;
- }
- }
/* not found */
- put_css_set(newcg);
return false;
}
@@ -1985,21 +2062,21 @@ static int css_set_prefetch(struct cgroup *cgrp, struct css_set *cg,
* @cgrp: the cgroup to attach to
* @leader: the threadgroup leader task_struct of the group to be attached
*
- * Call holding cgroup_mutex and the threadgroup_fork_lock of the leader. Will
- * take task_lock of each thread in leader's threadgroup individually in turn.
+ * Call holding cgroup_mutex and the group_rwsem of the leader. Will take
+ * task_lock of each thread in leader's threadgroup individually in turn.
*/
-int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader)
+static int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader)
{
int retval, i, group_size;
struct cgroup_subsys *ss, *failed_ss = NULL;
- bool cancel_failed_ss = false;
/* guaranteed to be initialized later, but the compiler needs this */
- struct cgroup *oldcgrp = NULL;
struct css_set *oldcg;
struct cgroupfs_root *root = cgrp->root;
/* threadgroup list cursor and array */
struct task_struct *tsk;
+ struct task_and_cgroup *tc;
struct flex_array *group;
+ struct cgroup_taskset tset = { };
/*
* we need to make sure we have css_sets for all the tasks we're
* going to move -before- we actually start moving them, so that in
@@ -2012,13 +2089,12 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader)
* step 0: in order to do expensive, possibly blocking operations for
* every thread, we cannot iterate the thread group list, since it needs
* rcu or tasklist locked. instead, build an array of all threads in the
- * group - threadgroup_fork_lock prevents new threads from appearing,
- * and if threads exit, this will just be an over-estimate.
+ * group - group_rwsem prevents new threads from appearing, and if
+ * threads exit, this will just be an over-estimate.
*/
group_size = get_nr_threads(leader);
/* flex_array supports very large thread-groups better than kmalloc. */
- group = flex_array_alloc(sizeof(struct task_struct *), group_size,
- GFP_KERNEL);
+ group = flex_array_alloc(sizeof(*tc), group_size, GFP_KERNEL);
if (!group)
return -ENOMEM;
/* pre-allocate to guarantee space while iterating in rcu read-side. */
@@ -2040,49 +2116,53 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader)
retval = -EAGAIN;
goto out_free_group_list;
}
- /* take a reference on each task in the group to go in the array. */
+
tsk = leader;
i = 0;
do {
+ struct task_and_cgroup ent;
+
+ /* @tsk either already exited or can't exit until the end */
+ if (tsk->flags & PF_EXITING)
+ continue;
+
/* as per above, nr_threads may decrease, but not increase. */
BUG_ON(i >= group_size);
- get_task_struct(tsk);
/*
* saying GFP_ATOMIC has no effect here because we did prealloc
* earlier, but it's good form to communicate our expectations.
*/
- retval = flex_array_put_ptr(group, i, tsk, GFP_ATOMIC);
+ ent.task = tsk;
+ ent.cgrp = task_cgroup_from_root(tsk, root);
+ /* nothing to do if this task is already in the cgroup */
+ if (ent.cgrp == cgrp)
+ continue;
+ retval = flex_array_put(group, i, &ent, GFP_ATOMIC);
BUG_ON(retval != 0);
i++;
} while_each_thread(leader, tsk);
/* remember the number of threads in the array for later. */
group_size = i;
+ tset.tc_array = group;
+ tset.tc_array_len = group_size;
read_unlock(&tasklist_lock);
+ /* methods shouldn't be called if no task is actually migrating */
+ retval = 0;
+ if (!group_size)
+ goto out_free_group_list;
+
/*
* step 1: check that we can legitimately attach to the cgroup.
*/
for_each_subsys(root, ss) {
if (ss->can_attach) {
- retval = ss->can_attach(ss, cgrp, leader);
+ retval = ss->can_attach(ss, cgrp, &tset);
if (retval) {
failed_ss = ss;
goto out_cancel_attach;
}
}
- /* a callback to be run on every thread in the threadgroup. */
- if (ss->can_attach_task) {
- /* run on each task in the threadgroup. */
- for (i = 0; i < group_size; i++) {
- tsk = flex_array_get_ptr(group, i);
- retval = ss->can_attach_task(cgrp, tsk);
- if (retval) {
- failed_ss = ss;
- cancel_failed_ss = true;
- goto out_cancel_attach;
- }
- }
- }
}
/*
@@ -2091,67 +2171,36 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader)
*/
INIT_LIST_HEAD(&newcg_list);
for (i = 0; i < group_size; i++) {
- tsk = flex_array_get_ptr(group, i);
- /* nothing to do if this task is already in the cgroup */
- oldcgrp = task_cgroup_from_root(tsk, root);
- if (cgrp == oldcgrp)
- continue;
- /* get old css_set pointer */
- task_lock(tsk);
- oldcg = tsk->cgroups;
- get_css_set(oldcg);
- task_unlock(tsk);
- /* see if the new one for us is already in the list? */
- if (css_set_check_fetched(cgrp, tsk, oldcg, &newcg_list)) {
- /* was already there, nothing to do. */
- put_css_set(oldcg);
- } else {
- /* we don't already have it. get new one. */
+ tc = flex_array_get(group, i);
+ oldcg = tc->task->cgroups;
+
+ /* if we don't already have it in the list get a new one */
+ if (!css_set_check_fetched(cgrp, tc->task, oldcg,
+ &newcg_list)) {
retval = css_set_prefetch(cgrp, oldcg, &newcg_list);
- put_css_set(oldcg);
if (retval)
goto out_list_teardown;
}
}
/*
- * step 3: now that we're guaranteed success wrt the css_sets, proceed
- * to move all tasks to the new cgroup, calling ss->attach_task for each
- * one along the way. there are no failure cases after here, so this is
- * the commit point.
+ * step 3: now that we're guaranteed success wrt the css_sets,
+ * proceed to move all tasks to the new cgroup. There are no
+ * failure cases after here, so this is the commit point.
*/
- for_each_subsys(root, ss) {
- if (ss->pre_attach)
- ss->pre_attach(cgrp);
- }
for (i = 0; i < group_size; i++) {
- tsk = flex_array_get_ptr(group, i);
- /* leave current thread as it is if it's already there */
- oldcgrp = task_cgroup_from_root(tsk, root);
- if (cgrp == oldcgrp)
- continue;
- /* if the thread is PF_EXITING, it can just get skipped. */
- retval = cgroup_task_migrate(cgrp, oldcgrp, tsk, true);
- if (retval == 0) {
- /* attach each task to each subsystem */
- for_each_subsys(root, ss) {
- if (ss->attach_task)
- ss->attach_task(cgrp, tsk);
- }
- } else {
- BUG_ON(retval != -ESRCH);
- }
+ tc = flex_array_get(group, i);
+ retval = cgroup_task_migrate(cgrp, tc->cgrp, tc->task, true);
+ BUG_ON(retval);
}
/* nothing is sensitive to fork() after this point. */
/*
- * step 4: do expensive, non-thread-specific subsystem callbacks.
- * TODO: if ever a subsystem needs to know the oldcgrp for each task
- * being moved, this call will need to be reworked to communicate that.
+ * step 4: do subsystem attach callbacks.
*/
for_each_subsys(root, ss) {
if (ss->attach)
- ss->attach(ss, cgrp, oldcgrp, leader);
+ ss->attach(ss, cgrp, &tset);
}
/*
@@ -2171,20 +2220,12 @@ out_cancel_attach:
/* same deal as in cgroup_attach_task */
if (retval) {
for_each_subsys(root, ss) {
- if (ss == failed_ss) {
- if (cancel_failed_ss && ss->cancel_attach)
- ss->cancel_attach(ss, cgrp, leader);
+ if (ss == failed_ss)
break;
- }
if (ss->cancel_attach)
- ss->cancel_attach(ss, cgrp, leader);
+ ss->cancel_attach(ss, cgrp, &tset);
}
}
- /* clean up the array of referenced threads in the group. */
- for (i = 0; i < group_size; i++) {
- tsk = flex_array_get_ptr(group, i);
- put_task_struct(tsk);
- }
out_free_group_list:
flex_array_free(group);
return retval;
@@ -2192,8 +2233,8 @@ out_free_group_list:
/*
* Find the task_struct of the task to attach by vpid and pass it along to the
- * function to attach either it or all tasks in its threadgroup. Will take
- * cgroup_mutex; may take task_lock of task.
+ * function to attach either it or all tasks in its threadgroup. Will lock
+ * cgroup_mutex and threadgroup; may take task_lock of task.
*/
static int attach_task_by_pid(struct cgroup *cgrp, u64 pid, bool threadgroup)
{
@@ -2220,13 +2261,7 @@ static int attach_task_by_pid(struct cgroup *cgrp, u64 pid, bool threadgroup)
* detect it later.
*/
tsk = tsk->group_leader;
- } else if (tsk->flags & PF_EXITING) {
- /* optimization for the single-task-only case */
- rcu_read_unlock();
- cgroup_unlock();
- return -ESRCH;
}
-
/*
* even if we're attaching all tasks in the thread group, we
* only need to check permissions on one of them.
@@ -2249,13 +2284,15 @@ static int attach_task_by_pid(struct cgroup *cgrp, u64 pid, bool threadgroup)
get_task_struct(tsk);
}
- if (threadgroup) {
- threadgroup_fork_write_lock(tsk);
+ threadgroup_lock(tsk);
+
+ if (threadgroup)
ret = cgroup_attach_proc(cgrp, tsk);
- threadgroup_fork_write_unlock(tsk);
- } else {
+ else
ret = cgroup_attach_task(cgrp, tsk);
- }
+
+ threadgroup_unlock(tsk);
+
put_task_struct(tsk);
cgroup_unlock();
return ret;
@@ -2306,7 +2343,9 @@ static int cgroup_release_agent_write(struct cgroup *cgrp, struct cftype *cft,
return -EINVAL;
if (!cgroup_lock_live_group(cgrp))
return -ENODEV;
+ mutex_lock(&cgroup_root_mutex);
strcpy(cgrp->root->release_agent_path, buffer);
+ mutex_unlock(&cgroup_root_mutex);
cgroup_unlock();
return 0;
}
@@ -2789,6 +2828,7 @@ static void cgroup_enable_task_cg_lists(void)
}
void cgroup_iter_start(struct cgroup *cgrp, struct cgroup_iter *it)
+ __acquires(css_set_lock)
{
/*
* The first time anyone tries to iterate across a cgroup,
@@ -2828,6 +2868,7 @@ struct task_struct *cgroup_iter_next(struct cgroup *cgrp,
}
void cgroup_iter_end(struct cgroup *cgrp, struct cgroup_iter *it)
+ __releases(css_set_lock)
{
read_unlock(&css_set_lock);
}
@@ -4491,20 +4532,31 @@ static const struct file_operations proc_cgroupstats_operations = {
*
* A pointer to the shared css_set was automatically copied in
* fork.c by dup_task_struct(). However, we ignore that copy, since
- * it was not made under the protection of RCU or cgroup_mutex, so
- * might no longer be a valid cgroup pointer. cgroup_attach_task() might
- * have already changed current->cgroups, allowing the previously
- * referenced cgroup group to be removed and freed.
+ * it was not made under the protection of RCU, cgroup_mutex or
+ * threadgroup_change_begin(), so it might no longer be a valid
+ * cgroup pointer. cgroup_attach_task() might have already changed
+ * current->cgroups, allowing the previously referenced cgroup
+ * group to be removed and freed.
+ *
+ * Outside the pointer validity we also need to process the css_set
+ * inheritance between threadgoup_change_begin() and
+ * threadgoup_change_end(), this way there is no leak in any process
+ * wide migration performed by cgroup_attach_proc() that could otherwise
+ * miss a thread because it is too early or too late in the fork stage.
*
* At the point that cgroup_fork() is called, 'current' is the parent
* task, and the passed argument 'child' points to the child task.
*/
void cgroup_fork(struct task_struct *child)
{
- task_lock(current);
+ /*
+ * We don't need to task_lock() current because current->cgroups
+ * can't be changed concurrently here. The parent obviously hasn't
+ * exited and called cgroup_exit(), and we are synchronized against
+ * cgroup migration through threadgroup_change_begin().
+ */
child->cgroups = current->cgroups;
get_css_set(child->cgroups);
- task_unlock(current);
INIT_LIST_HEAD(&child->cg_list);
}
@@ -4546,10 +4598,19 @@ void cgroup_post_fork(struct task_struct *child)
{
if (use_task_css_set_links) {
write_lock(&css_set_lock);
- task_lock(child);
- if (list_empty(&child->cg_list))
+ if (list_empty(&child->cg_list)) {
+ /*
+ * It's safe to use child->cgroups without task_lock()
+ * here because we are protected through
+ * threadgroup_change_begin() against concurrent
+ * css_set change in cgroup_task_migrate(). Also
+ * the task can't exit at that point until
+ * wake_up_new_task() is called, so we are protected
+ * against cgroup_exit() setting child->cgroup to
+ * init_css_set.
+ */
list_add(&child->cg_list, &child->cgroups->tasks);
- task_unlock(child);
+ }
write_unlock(&css_set_lock);
}
}
diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c
index fcb93fca782..fc0646b78a6 100644
--- a/kernel/cgroup_freezer.c
+++ b/kernel/cgroup_freezer.c
@@ -166,13 +166,17 @@ static bool is_task_frozen_enough(struct task_struct *task)
*/
static int freezer_can_attach(struct cgroup_subsys *ss,
struct cgroup *new_cgroup,
- struct task_struct *task)
+ struct cgroup_taskset *tset)
{
struct freezer *freezer;
+ struct task_struct *task;
/*
* Anything frozen can't move or be moved to/from.
*/
+ cgroup_taskset_for_each(task, new_cgroup, tset)
+ if (cgroup_freezing(task))
+ return -EBUSY;
freezer = cgroup_freezer(new_cgroup);
if (freezer->state != CGROUP_THAWED)
@@ -181,11 +185,6 @@ static int freezer_can_attach(struct cgroup_subsys *ss,
return 0;
}
-static int freezer_can_attach_task(struct cgroup *cgrp, struct task_struct *tsk)
-{
- return cgroup_freezing(tsk) ? -EBUSY : 0;
-}
-
static void freezer_fork(struct cgroup_subsys *ss, struct task_struct *task)
{
struct freezer *freezer;
@@ -381,10 +380,5 @@ struct cgroup_subsys freezer_subsys = {
.populate = freezer_populate,
.subsys_id = freezer_subsys_id,
.can_attach = freezer_can_attach,
- .can_attach_task = freezer_can_attach_task,
- .pre_attach = NULL,
- .attach_task = NULL,
- .attach = NULL,
.fork = freezer_fork,
- .exit = NULL,
};
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 0b1712dba58..a09ac2b9a66 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -1389,79 +1389,73 @@ static int fmeter_getrate(struct fmeter *fmp)
return val;
}
-/* Called by cgroups to determine if a cpuset is usable; cgroup_mutex held */
-static int cpuset_can_attach(struct cgroup_subsys *ss, struct cgroup *cont,
- struct task_struct *tsk)
-{
- struct cpuset *cs = cgroup_cs(cont);
-
- if (cpumask_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed))
- return -ENOSPC;
-
- /*
- * Kthreads bound to specific cpus cannot be moved to a new cpuset; we
- * cannot change their cpu affinity and isolating such threads by their
- * set of allowed nodes is unnecessary. Thus, cpusets are not
- * applicable for such threads. This prevents checking for success of
- * set_cpus_allowed_ptr() on all attached tasks before cpus_allowed may
- * be changed.
- */
- if (tsk->flags & PF_THREAD_BOUND)
- return -EINVAL;
-
- return 0;
-}
-
-static int cpuset_can_attach_task(struct cgroup *cgrp, struct task_struct *task)
-{
- return security_task_setscheduler(task);
-}
-
/*
* Protected by cgroup_lock. The nodemasks must be stored globally because
- * dynamically allocating them is not allowed in pre_attach, and they must
- * persist among pre_attach, attach_task, and attach.
+ * dynamically allocating them is not allowed in can_attach, and they must
+ * persist until attach.
*/
static cpumask_var_t cpus_attach;
static nodemask_t cpuset_attach_nodemask_from;
static nodemask_t cpuset_attach_nodemask_to;
-/* Set-up work for before attaching each task. */
-static void cpuset_pre_attach(struct cgroup *cont)
+/* Called by cgroups to determine if a cpuset is usable; cgroup_mutex held */
+static int cpuset_can_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
+ struct cgroup_taskset *tset)
{
- struct cpuset *cs = cgroup_cs(cont);
+ struct cpuset *cs = cgroup_cs(cgrp);
+ struct task_struct *task;
+ int ret;
+
+ if (cpumask_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed))
+ return -ENOSPC;
+
+ cgroup_taskset_for_each(task, cgrp, tset) {
+ /*
+ * Kthreads bound to specific cpus cannot be moved to a new
+ * cpuset; we cannot change their cpu affinity and
+ * isolating such threads by their set of allowed nodes is
+ * unnecessary. Thus, cpusets are not applicable for such
+ * threads. This prevents checking for success of
+ * set_cpus_allowed_ptr() on all attached tasks before
+ * cpus_allowed may be changed.
+ */
+ if (task->flags & PF_THREAD_BOUND)
+ return -EINVAL;
+ if ((ret = security_task_setscheduler(task)))
+ return ret;
+ }
+ /* prepare for attach */
if (cs == &top_cpuset)
cpumask_copy(cpus_attach, cpu_possible_mask);
else
guarantee_online_cpus(cs, cpus_attach);
guarantee_online_mems(cs, &cpuset_attach_nodemask_to);
-}
-
-/* Per-thread attachment work. */
-static void cpuset_attach_task(struct cgroup *cont, struct task_struct *tsk)
-{
- int err;
- struct cpuset *cs = cgroup_cs(cont);
- /*
- * can_attach beforehand should guarantee that this doesn't fail.
- * TODO: have a better way to handle failure here
- */
- err = set_cpus_allowed_ptr(tsk, cpus_attach);
- WARN_ON_ONCE(err);
-
- cpuset_change_task_nodemask(tsk, &cpuset_attach_nodemask_to);
- cpuset_update_task_spread_flag(cs, tsk);
+ return 0;
}
-static void cpuset_attach(struct cgroup_subsys *ss, struct cgroup *cont,
- struct cgroup *oldcont, struct task_struct *tsk)
+static void cpuset_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
+ struct cgroup_taskset *tset)
{
struct mm_struct *mm;
- struct cpuset *cs = cgroup_cs(cont);
- struct cpuset *oldcs = cgroup_cs(oldcont);
+ struct task_struct *task;
+ struct task_struct *leader = cgroup_taskset_first(tset);
+ struct cgroup *oldcgrp = cgroup_taskset_cur_cgroup(tset);
+ struct cpuset *cs = cgroup_cs(cgrp);
+ struct cpuset *oldcs = cgroup_cs(oldcgrp);
+
+ cgroup_taskset_for_each(task, cgrp, tset) {
+ /*
+ * can_attach beforehand should guarantee that this doesn't
+ * fail. TODO: have a better way to handle failure here
+ */
+ WARN_ON_ONCE(set_cpus_allowed_ptr(task, cpus_attach));
+
+ cpuset_change_task_nodemask(task, &cpuset_attach_nodemask_to);
+ cpuset_update_task_spread_flag(cs, task);
+ }
/*
* Change mm, possibly for multiple threads in a threadgroup. This is
@@ -1469,7 +1463,7 @@ static void cpuset_attach(struct cgroup_subsys *ss, struct cgroup *cont,
*/
cpuset_attach_nodemask_from = oldcs->mems_allowed;
cpuset_attach_nodemask_to = cs->mems_allowed;
- mm = get_task_mm(tsk);
+ mm = get_task_mm(leader);
if (mm) {
mpol_rebind_mm(mm, &cpuset_attach_nodemask_to);
if (is_memory_migrate(cs))
@@ -1925,9 +1919,6 @@ struct cgroup_subsys cpuset_subsys = {
.create = cpuset_create,
.destroy = cpuset_destroy,
.can_attach = cpuset_can_attach,
- .can_attach_task = cpuset_can_attach_task,
- .pre_attach = cpuset_pre_attach,
- .attach_task = cpuset_attach_task,
.attach = cpuset_attach,
.populate = cpuset_populate,
.post_clone = cpuset_post_clone,
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 3afc68c0843..a8f4ac001a0 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -6941,10 +6941,13 @@ static int __perf_cgroup_move(void *info)
return 0;
}
-static void
-perf_cgroup_attach_task(struct cgroup *cgrp, struct task_struct *task)
+static void perf_cgroup_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
+ struct cgroup_taskset *tset)
{
- task_function_call(task, __perf_cgroup_move, task);
+ struct task_struct *task;
+
+ cgroup_taskset_for_each(task, cgrp, tset)
+ task_function_call(task, __perf_cgroup_move, task);
}
static void perf_cgroup_exit(struct cgroup_subsys *ss, struct cgroup *cgrp,
@@ -6958,7 +6961,7 @@ static void perf_cgroup_exit(struct cgroup_subsys *ss, struct cgroup *cgrp,
if (!(task->flags & PF_EXITING))
return;
- perf_cgroup_attach_task(cgrp, task);
+ task_function_call(task, __perf_cgroup_move, task);
}
struct cgroup_subsys perf_subsys = {
@@ -6967,6 +6970,6 @@ struct cgroup_subsys perf_subsys = {
.create = perf_cgroup_create,
.destroy = perf_cgroup_destroy,
.exit = perf_cgroup_exit,
- .attach_task = perf_cgroup_attach_task,
+ .attach = perf_cgroup_attach,
};
#endif /* CONFIG_CGROUP_PERF */
diff --git a/kernel/exit.c b/kernel/exit.c
index d9eab2e4b43..94ed6e20bb5 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -51,6 +51,7 @@
#include <trace/events/sched.h>
#include <linux/hw_breakpoint.h>
#include <linux/oom.h>
+#include <linux/writeback.h>
#include <asm/uaccess.h>
#include <asm/unistd.h>
@@ -1035,6 +1036,8 @@ NORET_TYPE void do_exit(long code)
validate_creds_for_do_exit(tsk);
preempt_disable();
+ if (tsk->nr_dirtied)
+ __this_cpu_add(dirty_throttle_leaks, tsk->nr_dirtied);
exit_rcu();
/* causes final put_task_struct in finish_task_switch(). */
tsk->state = TASK_DEAD;
diff --git a/kernel/fork.c b/kernel/fork.c
index f34f894c4b9..443f5125f11 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -76,6 +76,9 @@
#include <trace/events/sched.h>
+#define CREATE_TRACE_POINTS
+#include <trace/events/task.h>
+
/*
* Protected counters by write_lock_irq(&tasklist_lock)
*/
@@ -972,7 +975,7 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
sched_autogroup_fork(sig);
#ifdef CONFIG_CGROUPS
- init_rwsem(&sig->threadgroup_fork_lock);
+ init_rwsem(&sig->group_rwsem);
#endif
sig->oom_adj = current->signal->oom_adj;
@@ -1153,7 +1156,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
p->io_context = NULL;
p->audit_context = NULL;
if (clone_flags & CLONE_THREAD)
- threadgroup_fork_read_lock(current);
+ threadgroup_change_begin(current);
cgroup_fork(p);
#ifdef CONFIG_NUMA
p->mempolicy = mpol_dup(p->mempolicy);
@@ -1291,6 +1294,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
p->nr_dirtied = 0;
p->nr_dirtied_pause = 128 >> (PAGE_SHIFT - 10);
+ p->dirty_paused_when = 0;
/*
* Ok, make it visible to the rest of the system.
@@ -1368,8 +1372,11 @@ static struct task_struct *copy_process(unsigned long clone_flags,
proc_fork_connector(p);
cgroup_post_fork(p);
if (clone_flags & CLONE_THREAD)
- threadgroup_fork_read_unlock(current);
+ threadgroup_change_end(current);
perf_event_fork(p);
+
+ trace_task_newtask(p, clone_flags);
+
return p;
bad_fork_free_pid:
@@ -1403,7 +1410,7 @@ bad_fork_cleanup_policy:
bad_fork_cleanup_cgroup:
#endif
if (clone_flags & CLONE_THREAD)
- threadgroup_fork_read_unlock(current);
+ threadgroup_change_end(current);
cgroup_exit(p, cgroup_callbacks_done);
delayacct_tsk_free(p);
module_put(task_thread_info(p)->exec_domain->module);
diff --git a/kernel/jump_label.c b/kernel/jump_label.c
index 30c3c770813..01d3b70fc98 100644
--- a/kernel/jump_label.c
+++ b/kernel/jump_label.c
@@ -71,6 +71,7 @@ void jump_label_inc(struct jump_label_key *key)
atomic_inc(&key->enabled);
jump_label_unlock();
}
+EXPORT_SYMBOL_GPL(jump_label_inc);
static void __jump_label_dec(struct jump_label_key *key,
unsigned long rate_limit, struct delayed_work *work)
@@ -86,6 +87,7 @@ static void __jump_label_dec(struct jump_label_key *key,
jump_label_unlock();
}
+EXPORT_SYMBOL_GPL(jump_label_dec);
static void jump_label_update_timeout(struct work_struct *work)
{
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index cbe2c144139..1cf88900ec4 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -858,6 +858,9 @@ static struct page *saveable_highmem_page(struct zone *zone, unsigned long pfn)
PageReserved(page))
return NULL;
+ if (page_is_guard(page))
+ return NULL;
+
return page;
}
@@ -920,6 +923,9 @@ static struct page *saveable_page(struct zone *zone, unsigned long pfn)
&& (!kernel_page_present(page) || pfn_is_nosave(pfn)))
return NULL;
+ if (page_is_guard(page))
+ return NULL;
+
return page;
}
diff --git a/kernel/res_counter.c b/kernel/res_counter.c
index 34683efa2cc..6d269cce7aa 100644
--- a/kernel/res_counter.c
+++ b/kernel/res_counter.c
@@ -159,8 +159,7 @@ int res_counter_memparse_write_strategy(const char *buf,
return 0;
}
- /* FIXME - make memparse() take const char* args */
- *res = memparse((char *)buf, &end);
+ *res = memparse(buf, &end);
if (*end != '\0')
return -EINVAL;
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 0ac0f811d62..cecbb64be05 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -7563,24 +7563,31 @@ cpu_cgroup_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp)
sched_destroy_group(tg);
}
-static int
-cpu_cgroup_can_attach_task(struct cgroup *cgrp, struct task_struct *tsk)
+static int cpu_cgroup_can_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
+ struct cgroup_taskset *tset)
{
+ struct task_struct *task;
+
+ cgroup_taskset_for_each(task, cgrp, tset) {
#ifdef CONFIG_RT_GROUP_SCHED
- if (!sched_rt_can_attach(cgroup_tg(cgrp), tsk))
- return -EINVAL;
+ if (!sched_rt_can_attach(cgroup_tg(cgrp), task))
+ return -EINVAL;
#else
- /* We don't support RT-tasks being in separate groups */
- if (tsk->sched_class != &fair_sched_class)
- return -EINVAL;
+ /* We don't support RT-tasks being in separate groups */
+ if (task->sched_class != &fair_sched_class)
+ return -EINVAL;
#endif
+ }
return 0;
}
-static void
-cpu_cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk)
+static void cpu_cgroup_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
+ struct cgroup_taskset *tset)
{
- sched_move_task(tsk);
+ struct task_struct *task;
+
+ cgroup_taskset_for_each(task, cgrp, tset)
+ sched_move_task(task);
}
static void
@@ -7915,8 +7922,8 @@ struct cgroup_subsys cpu_cgroup_subsys = {
.name = "cpu",
.create = cpu_cgroup_create,
.destroy = cpu_cgroup_destroy,
- .can_attach_task = cpu_cgroup_can_attach_task,
- .attach_task = cpu_cgroup_attach_task,
+ .can_attach = cpu_cgroup_can_attach,
+ .attach = cpu_cgroup_attach,
.exit = cpu_cgroup_exit,
.populate = cpu_cgroup_populate,
.subsys_id = cpu_cgroup_subsys_id,
diff --git a/kernel/signal.c b/kernel/signal.c
index 56ce3a618b2..c73c4284160 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -28,6 +28,7 @@
#include <linux/freezer.h>
#include <linux/pid_namespace.h>
#include <linux/nsproxy.h>
+#include <linux/user_namespace.h>
#define CREATE_TRACE_POINTS
#include <trace/events/signal.h>
@@ -1019,6 +1020,34 @@ static inline int legacy_queue(struct sigpending *signals, int sig)
return (sig < SIGRTMIN) && sigismember(&signals->signal, sig);
}
+/*
+ * map the uid in struct cred into user namespace *ns
+ */
+static inline uid_t map_cred_ns(const struct cred *cred,
+ struct user_namespace *ns)
+{
+ return user_ns_map_uid(ns, cred, cred->uid);
+}
+
+#ifdef CONFIG_USER_NS
+static inline void userns_fixup_signal_uid(struct siginfo *info, struct task_struct *t)
+{
+ if (current_user_ns() == task_cred_xxx(t, user_ns))
+ return;
+
+ if (SI_FROMKERNEL(info))
+ return;
+
+ info->si_uid = user_ns_map_uid(task_cred_xxx(t, user_ns),
+ current_cred(), info->si_uid);
+}
+#else
+static inline void userns_fixup_signal_uid(struct siginfo *info, struct task_struct *t)
+{
+ return;
+}
+#endif
+
static int __send_signal(int sig, struct siginfo *info, struct task_struct *t,
int group, int from_ancestor_ns)
{
@@ -1088,6 +1117,9 @@ static int __send_signal(int sig, struct siginfo *info, struct task_struct *t,
q->info.si_pid = 0;
break;
}
+
+ userns_fixup_signal_uid(&q->info, t);
+
} else if (!is_si_special(info)) {
if (sig >= SIGRTMIN && info->si_code != SI_USER) {
/*
@@ -1626,7 +1658,8 @@ bool do_notify_parent(struct task_struct *tsk, int sig)
*/
rcu_read_lock();
info.si_pid = task_pid_nr_ns(tsk, tsk->parent->nsproxy->pid_ns);
- info.si_uid = __task_cred(tsk)->uid;
+ info.si_uid = map_cred_ns(__task_cred(tsk),
+ task_cred_xxx(tsk->parent, user_ns));
rcu_read_unlock();
info.si_utime = cputime_to_clock_t(tsk->utime + tsk->signal->utime);
@@ -1709,7 +1742,8 @@ static void do_notify_parent_cldstop(struct task_struct *tsk,
*/
rcu_read_lock();
info.si_pid = task_pid_nr_ns(tsk, parent->nsproxy->pid_ns);
- info.si_uid = __task_cred(tsk)->uid;
+ info.si_uid = map_cred_ns(__task_cred(tsk),
+ task_cred_xxx(parent, user_ns));
rcu_read_unlock();
info.si_utime = cputime_to_clock_t(tsk->utime);
@@ -2125,8 +2159,11 @@ static int ptrace_signal(int signr, siginfo_t *info,
info->si_signo = signr;
info->si_errno = 0;
info->si_code = SI_USER;
+ rcu_read_lock();
info->si_pid = task_pid_vnr(current->parent);
- info->si_uid = task_uid(current->parent);
+ info->si_uid = map_cred_ns(__task_cred(current->parent),
+ current_user_ns());
+ rcu_read_unlock();
}
/* If the (new) signal is now blocked, requeue it. */
@@ -2318,6 +2355,27 @@ relock:
return signr;
}
+/**
+ * block_sigmask - add @ka's signal mask to current->blocked
+ * @ka: action for @signr
+ * @signr: signal that has been successfully delivered
+ *
+ * This function should be called when a signal has succesfully been
+ * delivered. It adds the mask of signals for @ka to current->blocked
+ * so that they are blocked during the execution of the signal
+ * handler. In addition, @signr will be blocked unless %SA_NODEFER is
+ * set in @ka->sa.sa_flags.
+ */
+void block_sigmask(struct k_sigaction *ka, int signr)
+{
+ sigset_t blocked;
+
+ sigorsets(&blocked, &current->blocked, &ka->sa.sa_mask);
+ if (!(ka->sa.sa_flags & SA_NODEFER))
+ sigaddset(&blocked, signr);
+ set_current_blocked(&blocked);
+}
+
/*
* It could be that complete_signal() picked us to notify about the
* group-wide signal. Other threads should be notified now to take
@@ -2355,8 +2413,15 @@ void exit_signals(struct task_struct *tsk)
int group_stop = 0;
sigset_t unblocked;
+ /*
+ * @tsk is about to have PF_EXITING set - lock out users which
+ * expect stable threadgroup.
+ */
+ threadgroup_change_begin(tsk);
+
if (thread_group_empty(tsk) || signal_group_exit(tsk->signal)) {
tsk->flags |= PF_EXITING;
+ threadgroup_change_end(tsk);
return;
}
@@ -2366,6 +2431,9 @@ void exit_signals(struct task_struct *tsk)
* see wants_signal(), do_signal_stop().
*/
tsk->flags |= PF_EXITING;
+
+ threadgroup_change_end(tsk);
+
if (!signal_pending(tsk))
goto out;
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 42fa9ad0a81..bec7b5b53e0 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -242,10 +242,10 @@ struct workqueue_struct {
int nr_drainers; /* W: drain in progress */
int saved_max_active; /* W: saved cwq max_active */
- const char *name; /* I: workqueue name */
#ifdef CONFIG_LOCKDEP
struct lockdep_map lockdep_map;
#endif
+ char name[]; /* I: workqueue name */
};
struct workqueue_struct *system_wq __read_mostly;
@@ -2954,14 +2954,29 @@ static int wq_clamp_max_active(int max_active, unsigned int flags,
return clamp_val(max_active, 1, lim);
}
-struct workqueue_struct *__alloc_workqueue_key(const char *name,
+struct workqueue_struct *__alloc_workqueue_key(const char *fmt,
unsigned int flags,
int max_active,
struct lock_class_key *key,
- const char *lock_name)
+ const char *lock_name, ...)
{
+ va_list args, args1;
struct workqueue_struct *wq;
unsigned int cpu;
+ size_t namelen;
+
+ /* determine namelen, allocate wq and format name */
+ va_start(args, lock_name);
+ va_copy(args1, args);
+ namelen = vsnprintf(NULL, 0, fmt, args) + 1;
+
+ wq = kzalloc(sizeof(*wq) + namelen, GFP_KERNEL);
+ if (!wq)
+ goto err;
+
+ vsnprintf(wq->name, namelen, fmt, args1);
+ va_end(args);
+ va_end(args1);
/*
* Workqueues which may be used during memory reclaim should
@@ -2978,12 +2993,9 @@ struct workqueue_struct *__alloc_workqueue_key(const char *name,
flags |= WQ_HIGHPRI;
max_active = max_active ?: WQ_DFL_ACTIVE;
- max_active = wq_clamp_max_active(max_active, flags, name);
-
- wq = kzalloc(sizeof(*wq), GFP_KERNEL);
- if (!wq)
- goto err;
+ max_active = wq_clamp_max_active(max_active, flags, wq->name);
+ /* init wq */
wq->flags = flags;
wq->saved_max_active = max_active;
mutex_init(&wq->flush_mutex);
@@ -2991,7 +3003,6 @@ struct workqueue_struct *__alloc_workqueue_key(const char *name,
INIT_LIST_HEAD(&wq->flusher_queue);
INIT_LIST_HEAD(&wq->flusher_overflow);
- wq->name = name;
lockdep_init_map(&wq->lockdep_map, lock_name, key, 0);
INIT_LIST_HEAD(&wq->list);
@@ -3020,7 +3031,8 @@ struct workqueue_struct *__alloc_workqueue_key(const char *name,
if (!rescuer)
goto err;
- rescuer->task = kthread_create(rescuer_thread, wq, "%s", name);
+ rescuer->task = kthread_create(rescuer_thread, wq, "%s",
+ wq->name);
if (IS_ERR(rescuer->task))
goto err;
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-29 06:34:30 +0000