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authorLinus Torvalds <torvalds@linux-foundation.org>2014-12-10 18:34:42 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2014-12-10 18:34:42 -0800
commitb6da0076bab5a12afb19312ffee41c95490af2a0 (patch)
tree52a5675b9c2ff95d88b981d5b9a3822f6073c112 /kernel
parentcbfe0de303a55ed96d8831c2d5f56f8131cd6612 (diff)
parenta53b831549141aa060a8b54b76e3a42870d74cc0 (diff)
downloadlinux-b6da0076bab5a12afb19312ffee41c95490af2a0.tar.bz2
Merge branch 'akpm' (patchbomb from Andrew)
Merge first patchbomb from Andrew Morton: - a few minor cifs fixes - dma-debug upadtes - ocfs2 - slab - about half of MM - procfs - kernel/exit.c - panic.c tweaks - printk upates - lib/ updates - checkpatch updates - fs/binfmt updates - the drivers/rtc tree - nilfs - kmod fixes - more kernel/exit.c - various other misc tweaks and fixes * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (190 commits) exit: pidns: fix/update the comments in zap_pid_ns_processes() exit: pidns: alloc_pid() leaks pid_namespace if child_reaper is exiting exit: exit_notify: re-use "dead" list to autoreap current exit: reparent: call forget_original_parent() under tasklist_lock exit: reparent: avoid find_new_reaper() if no children exit: reparent: introduce find_alive_thread() exit: reparent: introduce find_child_reaper() exit: reparent: document the ->has_child_subreaper checks exit: reparent: s/while_each_thread/for_each_thread/ in find_new_reaper() exit: reparent: fix the cross-namespace PR_SET_CHILD_SUBREAPER reparenting exit: reparent: fix the dead-parent PR_SET_CHILD_SUBREAPER reparenting exit: proc: don't try to flush /proc/tgid/task/tgid exit: release_task: fix the comment about group leader accounting exit: wait: drop tasklist_lock before psig->c* accounting exit: wait: don't use zombie->real_parent exit: wait: cleanup the ptrace_reparented() checks usermodehelper: kill the kmod_thread_locker logic usermodehelper: don't use CLONE_VFORK for ____call_usermodehelper() fs/hfs/catalog.c: fix comparison bug in hfs_cat_keycmp nilfs2: fix the nilfs_iget() vs. nilfs_new_inode() races ...
Diffstat (limited to 'kernel')
-rw-r--r--kernel/Makefile1
-rw-r--r--kernel/exit.c245
-rw-r--r--kernel/kmod.c43
-rw-r--r--kernel/panic.c13
-rw-r--r--kernel/pid.c2
-rw-r--r--kernel/pid_namespace.c28
-rw-r--r--kernel/printk/printk.c49
-rw-r--r--kernel/ptrace.c23
-rw-r--r--kernel/res_counter.c211
-rw-r--r--kernel/sched/core.c4
-rw-r--r--kernel/sysctl.c9
-rw-r--r--kernel/sysctl_binary.c1
12 files changed, 205 insertions, 424 deletions
diff --git a/kernel/Makefile b/kernel/Makefile
index 17ea6d4a9a24..a59481a3fa6c 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -57,7 +57,6 @@ obj-$(CONFIG_UTS_NS) += utsname.o
obj-$(CONFIG_USER_NS) += user_namespace.o
obj-$(CONFIG_PID_NS) += pid_namespace.o
obj-$(CONFIG_IKCONFIG) += configs.o
-obj-$(CONFIG_RESOURCE_COUNTERS) += res_counter.o
obj-$(CONFIG_SMP) += stop_machine.o
obj-$(CONFIG_KPROBES_SANITY_TEST) += test_kprobes.o
obj-$(CONFIG_AUDIT) += audit.o auditfilter.o
diff --git a/kernel/exit.c b/kernel/exit.c
index 232c4bc8bcc9..8714e5ded8b4 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -118,13 +118,10 @@ static void __exit_signal(struct task_struct *tsk)
}
/*
- * Accumulate here the counters for all threads but the group leader
- * as they die, so they can be added into the process-wide totals
- * when those are taken. The group leader stays around as a zombie as
- * long as there are other threads. When it gets reaped, the exit.c
- * code will add its counts into these totals. We won't ever get here
- * for the group leader, since it will have been the last reference on
- * the signal_struct.
+ * Accumulate here the counters for all threads as they die. We could
+ * skip the group leader because it is the last user of signal_struct,
+ * but we want to avoid the race with thread_group_cputime() which can
+ * see the empty ->thread_head list.
*/
task_cputime(tsk, &utime, &stime);
write_seqlock(&sig->stats_lock);
@@ -462,6 +459,44 @@ static void exit_mm(struct task_struct *tsk)
clear_thread_flag(TIF_MEMDIE);
}
+static struct task_struct *find_alive_thread(struct task_struct *p)
+{
+ struct task_struct *t;
+
+ for_each_thread(p, t) {
+ if (!(t->flags & PF_EXITING))
+ return t;
+ }
+ return NULL;
+}
+
+static struct task_struct *find_child_reaper(struct task_struct *father)
+ __releases(&tasklist_lock)
+ __acquires(&tasklist_lock)
+{
+ struct pid_namespace *pid_ns = task_active_pid_ns(father);
+ struct task_struct *reaper = pid_ns->child_reaper;
+
+ if (likely(reaper != father))
+ return reaper;
+
+ reaper = find_alive_thread(father);
+ if (reaper) {
+ pid_ns->child_reaper = reaper;
+ return reaper;
+ }
+
+ write_unlock_irq(&tasklist_lock);
+ if (unlikely(pid_ns == &init_pid_ns)) {
+ panic("Attempted to kill init! exitcode=0x%08x\n",
+ father->signal->group_exit_code ?: father->exit_code);
+ }
+ zap_pid_ns_processes(pid_ns);
+ write_lock_irq(&tasklist_lock);
+
+ return father;
+}
+
/*
* When we die, we re-parent all our children, and try to:
* 1. give them to another thread in our thread group, if such a member exists
@@ -469,58 +504,36 @@ static void exit_mm(struct task_struct *tsk)
* child_subreaper for its children (like a service manager)
* 3. give it to the init process (PID 1) in our pid namespace
*/
-static struct task_struct *find_new_reaper(struct task_struct *father)
- __releases(&tasklist_lock)
- __acquires(&tasklist_lock)
+static struct task_struct *find_new_reaper(struct task_struct *father,
+ struct task_struct *child_reaper)
{
- struct pid_namespace *pid_ns = task_active_pid_ns(father);
- struct task_struct *thread;
+ struct task_struct *thread, *reaper;
- thread = father;
- while_each_thread(father, thread) {
- if (thread->flags & PF_EXITING)
- continue;
- if (unlikely(pid_ns->child_reaper == father))
- pid_ns->child_reaper = thread;
+ thread = find_alive_thread(father);
+ if (thread)
return thread;
- }
-
- if (unlikely(pid_ns->child_reaper == father)) {
- write_unlock_irq(&tasklist_lock);
- if (unlikely(pid_ns == &init_pid_ns)) {
- panic("Attempted to kill init! exitcode=0x%08x\n",
- father->signal->group_exit_code ?:
- father->exit_code);
- }
-
- zap_pid_ns_processes(pid_ns);
- write_lock_irq(&tasklist_lock);
- } else if (father->signal->has_child_subreaper) {
- struct task_struct *reaper;
+ if (father->signal->has_child_subreaper) {
/*
- * Find the first ancestor marked as child_subreaper.
- * Note that the code below checks same_thread_group(reaper,
- * pid_ns->child_reaper). This is what we need to DTRT in a
- * PID namespace. However we still need the check above, see
- * http://marc.info/?l=linux-kernel&m=131385460420380
+ * Find the first ->is_child_subreaper ancestor in our pid_ns.
+ * We start from father to ensure we can not look into another
+ * namespace, this is safe because all its threads are dead.
*/
- for (reaper = father->real_parent;
- reaper != &init_task;
+ for (reaper = father;
+ !same_thread_group(reaper, child_reaper);
reaper = reaper->real_parent) {
- if (same_thread_group(reaper, pid_ns->child_reaper))
+ /* call_usermodehelper() descendants need this check */
+ if (reaper == &init_task)
break;
if (!reaper->signal->is_child_subreaper)
continue;
- thread = reaper;
- do {
- if (!(thread->flags & PF_EXITING))
- return reaper;
- } while_each_thread(reaper, thread);
+ thread = find_alive_thread(reaper);
+ if (thread)
+ return thread;
}
}
- return pid_ns->child_reaper;
+ return child_reaper;
}
/*
@@ -529,15 +542,7 @@ static struct task_struct *find_new_reaper(struct task_struct *father)
static void reparent_leader(struct task_struct *father, struct task_struct *p,
struct list_head *dead)
{
- list_move_tail(&p->sibling, &p->real_parent->children);
-
- if (p->exit_state == EXIT_DEAD)
- return;
- /*
- * If this is a threaded reparent there is no need to
- * notify anyone anything has happened.
- */
- if (same_thread_group(p->real_parent, father))
+ if (unlikely(p->exit_state == EXIT_DEAD))
return;
/* We don't want people slaying init. */
@@ -548,49 +553,53 @@ static void reparent_leader(struct task_struct *father, struct task_struct *p,
p->exit_state == EXIT_ZOMBIE && thread_group_empty(p)) {
if (do_notify_parent(p, p->exit_signal)) {
p->exit_state = EXIT_DEAD;
- list_move_tail(&p->sibling, dead);
+ list_add(&p->ptrace_entry, dead);
}
}
kill_orphaned_pgrp(p, father);
}
-static void forget_original_parent(struct task_struct *father)
+/*
+ * This does two things:
+ *
+ * A. Make init inherit all the child processes
+ * B. Check to see if any process groups have become orphaned
+ * as a result of our exiting, and if they have any stopped
+ * jobs, send them a SIGHUP and then a SIGCONT. (POSIX 3.2.2.2)
+ */
+static void forget_original_parent(struct task_struct *father,
+ struct list_head *dead)
{
- struct task_struct *p, *n, *reaper;
- LIST_HEAD(dead_children);
+ struct task_struct *p, *t, *reaper;
- write_lock_irq(&tasklist_lock);
- /*
- * Note that exit_ptrace() and find_new_reaper() might
- * drop tasklist_lock and reacquire it.
- */
- exit_ptrace(father);
- reaper = find_new_reaper(father);
+ if (unlikely(!list_empty(&father->ptraced)))
+ exit_ptrace(father, dead);
- list_for_each_entry_safe(p, n, &father->children, sibling) {
- struct task_struct *t = p;
+ /* Can drop and reacquire tasklist_lock */
+ reaper = find_child_reaper(father);
+ if (list_empty(&father->children))
+ return;
- do {
+ reaper = find_new_reaper(father, reaper);
+ list_for_each_entry(p, &father->children, sibling) {
+ for_each_thread(p, t) {
t->real_parent = reaper;
- if (t->parent == father) {
- BUG_ON(t->ptrace);
+ BUG_ON((!t->ptrace) != (t->parent == father));
+ if (likely(!t->ptrace))
t->parent = t->real_parent;
- }
if (t->pdeath_signal)
group_send_sig_info(t->pdeath_signal,
SEND_SIG_NOINFO, t);
- } while_each_thread(p, t);
- reparent_leader(father, p, &dead_children);
- }
- write_unlock_irq(&tasklist_lock);
-
- BUG_ON(!list_empty(&father->children));
-
- list_for_each_entry_safe(p, n, &dead_children, sibling) {
- list_del_init(&p->sibling);
- release_task(p);
+ }
+ /*
+ * If this is a threaded reparent there is no need to
+ * notify anyone anything has happened.
+ */
+ if (!same_thread_group(reaper, father))
+ reparent_leader(father, p, dead);
}
+ list_splice_tail_init(&father->children, &reaper->children);
}
/*
@@ -600,18 +609,12 @@ static void forget_original_parent(struct task_struct *father)
static void exit_notify(struct task_struct *tsk, int group_dead)
{
bool autoreap;
-
- /*
- * This does two things:
- *
- * A. Make init inherit all the child processes
- * B. Check to see if any process groups have become orphaned
- * as a result of our exiting, and if they have any stopped
- * jobs, send them a SIGHUP and then a SIGCONT. (POSIX 3.2.2.2)
- */
- forget_original_parent(tsk);
+ struct task_struct *p, *n;
+ LIST_HEAD(dead);
write_lock_irq(&tasklist_lock);
+ forget_original_parent(tsk, &dead);
+
if (group_dead)
kill_orphaned_pgrp(tsk->group_leader, NULL);
@@ -629,15 +632,18 @@ static void exit_notify(struct task_struct *tsk, int group_dead)
}
tsk->exit_state = autoreap ? EXIT_DEAD : EXIT_ZOMBIE;
+ if (tsk->exit_state == EXIT_DEAD)
+ list_add(&tsk->ptrace_entry, &dead);
/* mt-exec, de_thread() is waiting for group leader */
if (unlikely(tsk->signal->notify_count < 0))
wake_up_process(tsk->signal->group_exit_task);
write_unlock_irq(&tasklist_lock);
- /* If the process is dead, release it - nobody will wait for it */
- if (autoreap)
- release_task(tsk);
+ list_for_each_entry_safe(p, n, &dead, ptrace_entry) {
+ list_del_init(&p->ptrace_entry);
+ release_task(p);
+ }
}
#ifdef CONFIG_DEBUG_STACK_USAGE
@@ -982,8 +988,7 @@ static int wait_noreap_copyout(struct wait_opts *wo, struct task_struct *p,
*/
static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
{
- unsigned long state;
- int retval, status, traced;
+ int state, retval, status;
pid_t pid = task_pid_vnr(p);
uid_t uid = from_kuid_munged(current_user_ns(), task_uid(p));
struct siginfo __user *infop;
@@ -1008,21 +1013,25 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
}
return wait_noreap_copyout(wo, p, pid, uid, why, status);
}
-
- traced = ptrace_reparented(p);
/*
* Move the task's state to DEAD/TRACE, only one thread can do this.
*/
- state = traced && thread_group_leader(p) ? EXIT_TRACE : EXIT_DEAD;
+ state = (ptrace_reparented(p) && thread_group_leader(p)) ?
+ EXIT_TRACE : EXIT_DEAD;
if (cmpxchg(&p->exit_state, EXIT_ZOMBIE, state) != EXIT_ZOMBIE)
return 0;
/*
- * It can be ptraced but not reparented, check
- * thread_group_leader() to filter out sub-threads.
+ * We own this thread, nobody else can reap it.
*/
- if (likely(!traced) && thread_group_leader(p)) {
- struct signal_struct *psig;
- struct signal_struct *sig;
+ read_unlock(&tasklist_lock);
+ sched_annotate_sleep();
+
+ /*
+ * Check thread_group_leader() to exclude the traced sub-threads.
+ */
+ if (state == EXIT_DEAD && thread_group_leader(p)) {
+ struct signal_struct *sig = p->signal;
+ struct signal_struct *psig = current->signal;
unsigned long maxrss;
cputime_t tgutime, tgstime;
@@ -1034,21 +1043,20 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
* accumulate in the parent's signal_struct c* fields.
*
* We don't bother to take a lock here to protect these
- * p->signal fields, because they are only touched by
- * __exit_signal, which runs with tasklist_lock
- * write-locked anyway, and so is excluded here. We do
- * need to protect the access to parent->signal fields,
- * as other threads in the parent group can be right
- * here reaping other children at the same time.
+ * p->signal fields because the whole thread group is dead
+ * and nobody can change them.
+ *
+ * psig->stats_lock also protects us from our sub-theads
+ * which can reap other children at the same time. Until
+ * we change k_getrusage()-like users to rely on this lock
+ * we have to take ->siglock as well.
*
* We use thread_group_cputime_adjusted() to get times for
* the thread group, which consolidates times for all threads
* in the group including the group leader.
*/
thread_group_cputime_adjusted(p, &tgutime, &tgstime);
- spin_lock_irq(&p->real_parent->sighand->siglock);
- psig = p->real_parent->signal;
- sig = p->signal;
+ spin_lock_irq(&current->sighand->siglock);
write_seqlock(&psig->stats_lock);
psig->cutime += tgutime + sig->cutime;
psig->cstime += tgstime + sig->cstime;
@@ -1073,16 +1081,9 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
task_io_accounting_add(&psig->ioac, &p->ioac);
task_io_accounting_add(&psig->ioac, &sig->ioac);
write_sequnlock(&psig->stats_lock);
- spin_unlock_irq(&p->real_parent->sighand->siglock);
+ spin_unlock_irq(&current->sighand->siglock);
}
- /*
- * Now we are sure this task is interesting, and no other
- * thread can reap it because we its state == DEAD/TRACE.
- */
- read_unlock(&tasklist_lock);
- sched_annotate_sleep();
-
retval = wo->wo_rusage
? getrusage(p, RUSAGE_BOTH, wo->wo_rusage) : 0;
status = (p->signal->flags & SIGNAL_GROUP_EXIT)
diff --git a/kernel/kmod.c b/kernel/kmod.c
index 80f7a6d00519..2777f40a9c7b 100644
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -47,13 +47,6 @@ extern int max_threads;
static struct workqueue_struct *khelper_wq;
-/*
- * kmod_thread_locker is used for deadlock avoidance. There is no explicit
- * locking to protect this global - it is private to the singleton khelper
- * thread and should only ever be modified by that thread.
- */
-static const struct task_struct *kmod_thread_locker;
-
#define CAP_BSET (void *)1
#define CAP_PI (void *)2
@@ -223,7 +216,6 @@ static void umh_complete(struct subprocess_info *sub_info)
static int ____call_usermodehelper(void *data)
{
struct subprocess_info *sub_info = data;
- int wait = sub_info->wait & ~UMH_KILLABLE;
struct cred *new;
int retval;
@@ -267,20 +259,13 @@ static int ____call_usermodehelper(void *data)
out:
sub_info->retval = retval;
/* wait_for_helper() will call umh_complete if UHM_WAIT_PROC. */
- if (wait != UMH_WAIT_PROC)
+ if (!(sub_info->wait & UMH_WAIT_PROC))
umh_complete(sub_info);
if (!retval)
return 0;
do_exit(0);
}
-static int call_helper(void *data)
-{
- /* Worker thread started blocking khelper thread. */
- kmod_thread_locker = current;
- return ____call_usermodehelper(data);
-}
-
/* Keventd can't block, but this (a child) can. */
static int wait_for_helper(void *data)
{
@@ -323,21 +308,14 @@ static void __call_usermodehelper(struct work_struct *work)
{
struct subprocess_info *sub_info =
container_of(work, struct subprocess_info, work);
- int wait = sub_info->wait & ~UMH_KILLABLE;
pid_t pid;
- /* CLONE_VFORK: wait until the usermode helper has execve'd
- * successfully We need the data structures to stay around
- * until that is done. */
- if (wait == UMH_WAIT_PROC)
+ if (sub_info->wait & UMH_WAIT_PROC)
pid = kernel_thread(wait_for_helper, sub_info,
CLONE_FS | CLONE_FILES | SIGCHLD);
- else {
- pid = kernel_thread(call_helper, sub_info,
- CLONE_VFORK | SIGCHLD);
- /* Worker thread stopped blocking khelper thread. */
- kmod_thread_locker = NULL;
- }
+ else
+ pid = kernel_thread(____call_usermodehelper, sub_info,
+ SIGCHLD);
if (pid < 0) {
sub_info->retval = pid;
@@ -571,17 +549,6 @@ int call_usermodehelper_exec(struct subprocess_info *sub_info, int wait)
goto out;
}
/*
- * Worker thread must not wait for khelper thread at below
- * wait_for_completion() if the thread was created with CLONE_VFORK
- * flag, for khelper thread is already waiting for the thread at
- * wait_for_completion() in do_fork().
- */
- if (wait != UMH_NO_WAIT && current == kmod_thread_locker) {
- retval = -EBUSY;
- goto out;
- }
-
- /*
* Set the completion pointer only if there is a waiter.
* This makes it possible to use umh_complete to free
* the data structure in case of UMH_NO_WAIT.
diff --git a/kernel/panic.c b/kernel/panic.c
index cf80672b7924..4d8d6f906dec 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -33,6 +33,7 @@ static int pause_on_oops;
static int pause_on_oops_flag;
static DEFINE_SPINLOCK(pause_on_oops_lock);
static bool crash_kexec_post_notifiers;
+int panic_on_warn __read_mostly;
int panic_timeout = CONFIG_PANIC_TIMEOUT;
EXPORT_SYMBOL_GPL(panic_timeout);
@@ -428,6 +429,17 @@ static void warn_slowpath_common(const char *file, int line, void *caller,
if (args)
vprintk(args->fmt, args->args);
+ if (panic_on_warn) {
+ /*
+ * This thread may hit another WARN() in the panic path.
+ * Resetting this prevents additional WARN() from panicking the
+ * system on this thread. Other threads are blocked by the
+ * panic_mutex in panic().
+ */
+ panic_on_warn = 0;
+ panic("panic_on_warn set ...\n");
+ }
+
print_modules();
dump_stack();
print_oops_end_marker();
@@ -485,6 +497,7 @@ EXPORT_SYMBOL(__stack_chk_fail);
core_param(panic, panic_timeout, int, 0644);
core_param(pause_on_oops, pause_on_oops, int, 0644);
+core_param(panic_on_warn, panic_on_warn, int, 0644);
static int __init setup_crash_kexec_post_notifiers(char *s)
{
diff --git a/kernel/pid.c b/kernel/pid.c
index 9b9a26698144..82430c858d69 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -341,6 +341,8 @@ out:
out_unlock:
spin_unlock_irq(&pidmap_lock);
+ put_pid_ns(ns);
+
out_free:
while (++i <= ns->level)
free_pidmap(pid->numbers + i);
diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c
index db95d8eb761b..bc6d6a89b6e6 100644
--- a/kernel/pid_namespace.c
+++ b/kernel/pid_namespace.c
@@ -190,7 +190,11 @@ void zap_pid_ns_processes(struct pid_namespace *pid_ns)
/* Don't allow any more processes into the pid namespace */
disable_pid_allocation(pid_ns);
- /* Ignore SIGCHLD causing any terminated children to autoreap */
+ /*
+ * Ignore SIGCHLD causing any terminated children to autoreap.
+ * This speeds up the namespace shutdown, plus see the comment
+ * below.
+ */
spin_lock_irq(&me->sighand->siglock);
me->sighand->action[SIGCHLD - 1].sa.sa_handler = SIG_IGN;
spin_unlock_irq(&me->sighand->siglock);
@@ -223,15 +227,31 @@ void zap_pid_ns_processes(struct pid_namespace *pid_ns)
}
read_unlock(&tasklist_lock);
- /* Firstly reap the EXIT_ZOMBIE children we may have. */
+ /*
+ * Reap the EXIT_ZOMBIE children we had before we ignored SIGCHLD.
+ * sys_wait4() will also block until our children traced from the
+ * parent namespace are detached and become EXIT_DEAD.
+ */
do {
clear_thread_flag(TIF_SIGPENDING);
rc = sys_wait4(-1, NULL, __WALL, NULL);
} while (rc != -ECHILD);
/*
- * sys_wait4() above can't reap the TASK_DEAD children.
- * Make sure they all go away, see free_pid().
+ * sys_wait4() above can't reap the EXIT_DEAD children but we do not
+ * really care, we could reparent them to the global init. We could
+ * exit and reap ->child_reaper even if it is not the last thread in
+ * this pid_ns, free_pid(nr_hashed == 0) calls proc_cleanup_work(),
+ * pid_ns can not go away until proc_kill_sb() drops the reference.
+ *
+ * But this ns can also have other tasks injected by setns()+fork().
+ * Again, ignoring the user visible semantics we do not really need
+ * to wait until they are all reaped, but they can be reparented to
+ * us and thus we need to ensure that pid->child_reaper stays valid
+ * until they all go away. See free_pid()->wake_up_process().
+ *
+ * We rely on ignored SIGCHLD, an injected zombie must be autoreaped
+ * if reparented.
*/
for (;;) {
set_current_state(TASK_UNINTERRUPTIBLE);
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index c8755e7e1dba..ea27c019655a 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -62,9 +62,6 @@ int console_printk[4] = {
CONSOLE_LOGLEVEL_DEFAULT, /* default_console_loglevel */
};
-/* Deferred messaged from sched code are marked by this special level */
-#define SCHED_MESSAGE_LOGLEVEL -2
-
/*
* Low level drivers may need that to know if they can schedule in
* their unblank() callback or not. So let's export it.
@@ -1259,7 +1256,7 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
int do_syslog(int type, char __user *buf, int len, bool from_file)
{
bool clear = false;
- static int saved_console_loglevel = -1;
+ static int saved_console_loglevel = LOGLEVEL_DEFAULT;
int error;
error = check_syslog_permissions(type, from_file);
@@ -1316,15 +1313,15 @@ int do_syslog(int type, char __user *buf, int len, bool from_file)
break;
/* Disable logging to console */
case SYSLOG_ACTION_CONSOLE_OFF:
- if (saved_console_loglevel == -1)
+ if (saved_console_loglevel == LOGLEVEL_DEFAULT)
saved_console_loglevel = console_loglevel;
console_loglevel = minimum_console_loglevel;
break;
/* Enable logging to console */
case SYSLOG_ACTION_CONSOLE_ON:
- if (saved_console_loglevel != -1) {
+ if (saved_console_loglevel != LOGLEVEL_DEFAULT) {
console_loglevel = saved_console_loglevel;
- saved_console_loglevel = -1;
+ saved_console_loglevel = LOGLEVEL_DEFAULT;
}
break;
/* Set level of messages printed to console */
@@ -1336,7 +1333,7 @@ int do_syslog(int type, char __user *buf, int len, bool from_file)
len = minimum_console_loglevel;
console_loglevel = len;
/* Implicitly re-enable logging to console */
- saved_console_loglevel = -1;
+ saved_console_loglevel = LOGLEVEL_DEFAULT;
error = 0;
break;
/* Number of chars in the log buffer */
@@ -1627,10 +1624,10 @@ asmlinkage int vprintk_emit(int facility, int level,
int printed_len = 0;
bool in_sched = false;
/* cpu currently holding logbuf_lock in this function */
- static volatile unsigned int logbuf_cpu = UINT_MAX;
+ static unsigned int logbuf_cpu = UINT_MAX;
- if (level == SCHED_MESSAGE_LOGLEVEL) {
- level = -1;
+ if (level == LOGLEVEL_SCHED) {
+ level = LOGLEVEL_DEFAULT;
in_sched = true;
}
@@ -1695,8 +1692,9 @@ asmlinkage int vprintk_emit(int facility, int level,
const char *end_of_header = printk_skip_level(text);
switch (kern_level) {
case '0' ... '7':
- if (level == -1)
+ if (level == LOGLEVEL_DEFAULT)
level = kern_level - '0';
+ /* fallthrough */
case 'd': /* KERN_DEFAULT */
lflags |= LOG_PREFIX;
}
@@ -1710,7 +1708,7 @@ asmlinkage int vprintk_emit(int facility, int level,
}
}
- if (level == -1)
+ if (level == LOGLEVEL_DEFAULT)
level = default_message_loglevel;
if (dict)
@@ -1788,7 +1786,7 @@ EXPORT_SYMBOL(vprintk_emit);
asmlinkage int vprintk(const char *fmt, va_list args)
{
- return vprintk_emit(0, -1, NULL, 0, fmt, args);
+ return vprintk_emit(0, LOGLEVEL_DEFAULT, NULL, 0, fmt, args);
}
EXPORT_SYMBOL(vprintk);
@@ -1842,7 +1840,7 @@ asmlinkage __visible int printk(const char *fmt, ...)
}
#endif
va_start(args, fmt);
- r = vprintk_emit(0, -1, NULL, 0, fmt, args);
+ r = vprintk_emit(0, LOGLEVEL_DEFAULT, NULL, 0, fmt, args);
va_end(args);
return r;
@@ -1881,23 +1879,20 @@ static size_t cont_print_text(char *text, size_t size) { return 0; }
#ifdef CONFIG_EARLY_PRINTK
struct console *early_console;
-void early_vprintk(const char *fmt, va_list ap)
-{
- if (early_console) {
- char buf[512];
- int n = vscnprintf(buf, sizeof(buf), fmt, ap);
-
- early_console->write(early_console, buf, n);
- }
-}
-
asmlinkage __visible void early_printk(const char *fmt, ...)
{
va_list ap;
+ char buf[512];
+ int n;
+
+ if (!early_console)
+ return;
va_start(ap, fmt);
- early_vprintk(fmt, ap);
+ n = vscnprintf(buf, sizeof(buf), fmt, ap);
va_end(ap);
+
+ early_console->write(early_console, buf, n);
}
#endif
@@ -2634,7 +2629,7 @@ int printk_deferred(const char *fmt, ...)
preempt_disable();
va_start(args, fmt);
- r = vprintk_emit(0, SCHED_MESSAGE_LOGLEVEL, NULL, 0, fmt, args);
+ r = vprintk_emit(0, LOGLEVEL_SCHED, NULL, 0, fmt, args);
va_end(args);
__this_cpu_or(printk_pending, PRINTK_PENDING_OUTPUT);
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 54e75226c2c4..1eb9d90c3af9 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -485,36 +485,19 @@ static int ptrace_detach(struct task_struct *child, unsigned int data)
/*
* Detach all tasks we were using ptrace on. Called with tasklist held
- * for writing, and returns with it held too. But note it can release
- * and reacquire the lock.
+ * for writing.
*/
-void exit_ptrace(struct task_struct *tracer)
- __releases(&tasklist_lock)
- __acquires(&tasklist_lock)
+void exit_ptrace(struct task_struct *tracer, struct list_head *dead)
{
struct task_struct *p, *n;
- LIST_HEAD(ptrace_dead);
-
- if (likely(list_empty(&tracer->ptraced)))
- return;
list_for_each_entry_safe(p, n, &tracer->ptraced, ptrace_entry) {
if (unlikely(p->ptrace & PT_EXITKILL))
send_sig_info(SIGKILL, SEND_SIG_FORCED, p);
if (__ptrace_detach(tracer, p))
- list_add(&p->ptrace_entry, &ptrace_dead);
- }
-
- write_unlock_irq(&tasklist_lock);
- BUG_ON(!list_empty(&tracer->ptraced));
-
- list_for_each_entry_safe(p, n, &ptrace_dead, ptrace_entry) {
- list_del_init(&p->ptrace_entry);
- release_task(p);
+ list_add(&p->ptrace_entry, dead);
}
-
- write_lock_irq(&tasklist_lock);
}
int ptrace_readdata(struct task_struct *tsk, unsigned long src, char __user *dst, int len)
diff --git a/kernel/res_counter.c b/kernel/res_counter.c
deleted file mode 100644
index e791130f85a7..000000000000
--- a/kernel/res_counter.c
+++ /dev/null
@@ -1,211 +0,0 @@
-/*
- * resource cgroups
- *
- * Copyright 2007 OpenVZ SWsoft Inc
- *
- * Author: Pavel Emelianov <xemul@openvz.org>
- *
- */
-
-#include <linux/types.h>
-#include <linux/parser.h>
-#include <linux/fs.h>
-#include <linux/res_counter.h>
-#include <linux/uaccess.h>
-#include <linux/mm.h>
-
-void res_counter_init(struct res_counter *counter, struct res_counter *parent)
-{
- spin_lock_init(&counter->lock);
- counter->limit = RES_COUNTER_MAX;
- counter->soft_limit = RES_COUNTER_MAX;
- counter->parent = parent;
-}
-
-static u64 res_counter_uncharge_locked(struct res_counter *counter,
- unsigned long val)
-{
- if (WARN_ON(counter->usage < val))
- val = counter->usage;
-
- counter->usage -= val;
- return counter->usage;
-}
-
-static int res_counter_charge_locked(struct res_counter *counter,
- unsigned long val, bool force)
-{
- int ret = 0;
-
- if (counter->usage + val > counter->limit) {
- counter->failcnt++;
- ret = -ENOMEM;
- if (!force)
- return ret;
- }
-
- counter->usage += val;
- if (counter->usage > counter->max_usage)
- counter->max_usage = counter->usage;
- return ret;
-}
-
-static int __res_counter_charge(struct res_counter *counter, unsigned long val,
- struct res_counter **limit_fail_at, bool force)
-{
- int ret, r;
- unsigned long flags;
- struct res_counter *c, *u;
-
- r = ret = 0;
- *limit_fail_at = NULL;
- local_irq_save(flags);
- for (c = counter; c != NULL; c = c->parent) {
- spin_lock(&c->lock);
- r = res_counter_charge_locked(c, val, force);
- spin_unlock(&c->lock);
- if (r < 0 && !ret) {
- ret = r;
- *limit_fail_at = c;
- if (!force)
- break;
- }
- }
-
- if (ret < 0 && !force) {
- for (u = counter; u != c; u = u->parent) {
- spin_lock(&u->lock);
- res_counter_uncharge_locked(u, val);
- spin_unlock(&u->lock);
- }
- }
- local_irq_restore(flags);
-
- return ret;
-}
-
-int res_counter_charge(struct res_counter *counter, unsigned long val,
- struct res_counter **limit_fail_at)
-{
- return __res_counter_charge(counter, val, limit_fail_at, false);
-}
-
-int res_counter_charge_nofail(struct res_counter *counter, unsigned long val,
- struct res_counter **limit_fail_at)
-{
- return __res_counter_charge(counter, val, limit_fail_at, true);
-}
-
-u64 res_counter_uncharge_until(struct res_counter *counter,
- struct res_counter *top,
- unsigned long val)
-{
- unsigned long flags;
- struct res_counter *c;
- u64 ret = 0;
-
- local_irq_save(flags);
- for (c = counter; c != top; c = c->parent) {
- u64 r;
- spin_lock(&c->lock);
- r = res_counter_uncharge_locked(c, val);
- if (c == counter)
- ret = r;
- spin_unlock(&c->lock);
- }
- local_irq_restore(flags);
- return ret;
-}
-
-u64 res_counter_uncharge(struct res_counter *counter, unsigned long val)
-{
- return res_counter_uncharge_until(counter, NULL, val);
-}
-
-static inline unsigned long long *
-res_counter_member(struct res_counter *counter, int member)
-{
- switch (member) {
- case RES_USAGE:
- return &counter->usage;
- case RES_MAX_USAGE:
- return &counter->max_usage;
- case RES_LIMIT:
- return &counter->limit;
- case RES_FAILCNT:
- return &counter->failcnt;
- case RES_SOFT_LIMIT:
- return &counter->soft_limit;
- };
-
- BUG();
- return NULL;
-}
-
-ssize_t res_counter_read(struct res_counter *counter, int member,
- const char __user *userbuf, size_t nbytes, loff_t *pos,
- int (*read_strategy)(unsigned long long val, char *st_buf))
-{
- unsigned long long *val;
- char buf[64], *s;
-
- s = buf;
- val = res_counter_member(counter, member);
- if (read_strategy)
- s += read_strategy(*val, s);
- else
- s += sprintf(s, "%llu\n", *val);
- return simple_read_from_buffer((void __user *)userbuf, nbytes,
- pos, buf, s - buf);
-}
-
-#if BITS_PER_LONG == 32
-u64 res_counter_read_u64(struct res_counter *counter, int member)
-{
- unsigned long flags;
- u64 ret;
-
- spin_lock_irqsave(&counter->lock, flags);
- ret = *res_counter_member(counter, member);
- spin_unlock_irqrestore(&counter->lock, flags);
-
- return ret;
-}
-#else
-u64 res_counter_read_u64(struct res_counter *counter, int member)
-{
- return *res_counter_member(counter, member);
-}
-#endif
-
-int res_counter_memparse_write_strategy(const char *buf,
- unsigned long long *resp)
-{
- char *end;
- unsigned long long res;
-
- /* return RES_COUNTER_MAX(unlimited) if "-1" is specified */
- if (*buf == '-') {
- int rc = kstrtoull(buf + 1, 10, &res);
-
- if (rc)
- return rc;
- if (res != 1)
- return -EINVAL;
- *resp = RES_COUNTER_MAX;
- return 0;
- }
-
- res = memparse(buf, &end);
- if (*end != '\0')
- return -EINVAL;
-
- if (PAGE_ALIGN(res) >= res)
- res = PAGE_ALIGN(res);
- else
- res = RES_COUNTER_MAX;
-
- *resp = res;
-
- return 0;
-}
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index bb398c0c5f08..b5797b78add6 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -4527,8 +4527,10 @@ void sched_show_task(struct task_struct *p)
#ifdef CONFIG_DEBUG_STACK_USAGE
free = stack_not_used(p);
#endif
+ ppid = 0;
rcu_read_lock();
- ppid = task_pid_nr(rcu_dereference(p->real_parent));
+ if (pid_alive(p))
+ ppid = task_pid_nr(rcu_dereference(p->real_parent));
rcu_read_unlock();
printk(KERN_CONT "%5lu %5d %6d 0x%08lx\n", free,
task_pid_nr(p), ppid,
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 15f2511a1b7c..7c54ff79afd7 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -1104,6 +1104,15 @@ static struct ctl_table kern_table[] = {
.proc_handler = proc_dointvec,
},
#endif
+ {
+ .procname = "panic_on_warn",
+ .data = &panic_on_warn,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = &zero,
+ .extra2 = &one,
+ },
{ }
};
diff --git a/kernel/sysctl_binary.c b/kernel/sysctl_binary.c
index 9a4f750a2963..7e7746a42a62 100644
--- a/kernel/sysctl_binary.c
+++ b/kernel/sysctl_binary.c
@@ -137,6 +137,7 @@ static const struct bin_table bin_kern_table[] = {
{ CTL_INT, KERN_COMPAT_LOG, "compat-log" },
{ CTL_INT, KERN_MAX_LOCK_DEPTH, "max_lock_depth" },
{ CTL_INT, KERN_PANIC_ON_NMI, "panic_on_unrecovered_nmi" },
+ { CTL_INT, KERN_PANIC_ON_WARN, "panic_on_warn" },
{}
};