4 files changed, 65 insertions, 36 deletions

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 2727f9238359..6d8de051382b 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -1722,7 +1722,12 @@ void cgroup_enable_task_cg_lists(void)
         use_task_css_set_links = 1;
         do_each_thread(g, p) {
                 task_lock(p);
-                if (list_empty(&p->cg_list))
+                /*
+                 * We should check if the process is exiting, otherwise
+                 * it will race with cgroup_exit() in that the list
+                 * entry won't be deleted though the process has exited.
+                 */
+                if (!(p->flags & PF_EXITING) && list_empty(&p->cg_list))
                         list_add(&p->cg_list, &p->cgroups->tasks);
                 task_unlock(p);
         } while_each_thread(g, p);
diff --git a/kernel/printk.c b/kernel/printk.c
index c46a20a19a15..bdd4ea8c3f2b 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -643,8 +643,21 @@ static int acquire_console_semaphore_for_printk(unsigned int cpu)
 {
         int retval = 0;
 
-        if (can_use_console(cpu))
-                retval = !try_acquire_console_sem();
+        if (!try_acquire_console_sem()) {
+                retval = 1;
+
+                /*
+                 * If we can't use the console, we need to release
+                 * the console semaphore by hand to avoid flushing
+                 * the buffer. We need to hold the console semaphore
+                 * in order to do this test safely.
+                 */
+                if (!can_use_console(cpu)) {
+                        console_locked = 0;
+                        up(&console_sem);
+                        retval = 0;
+                }
+        }
         printk_cpu = UINT_MAX;
         spin_unlock(&logbuf_lock);
         return retval;
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 86a93376282c..0080968d3e4a 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -510,10 +510,8 @@ place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial)
 
         if (!initial) {
                 /* sleeps upto a single latency don't count. */
-                if (sched_feat(NEW_FAIR_SLEEPERS)) {
-                        vruntime -= calc_delta_fair(sysctl_sched_latency,
-                                                    &cfs_rq->load);
-                }
+                if (sched_feat(NEW_FAIR_SLEEPERS))
+                        vruntime -= sysctl_sched_latency;
 
                 /* ensure we never gain time by being placed backwards. */
                 vruntime = max_vruntime(se->vruntime, vruntime);
diff --git a/kernel/signal.c b/kernel/signal.c
index 6af1210092c3..cc8303cd093d 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1757,6 +1757,45 @@ static int do_signal_stop(int signr)
         return 1;
 }
 
+static int ptrace_signal(int signr, siginfo_t *info,
+                         struct pt_regs *regs, void *cookie)
+{
+        if (!(current->ptrace & PT_PTRACED))
+                return signr;
+
+        ptrace_signal_deliver(regs, cookie);
+
+        /* Let the debugger run.  */
+        ptrace_stop(signr, 0, info);
+
+        /* We're back.  Did the debugger cancel the sig?  */
+        signr = current->exit_code;
+        if (signr == 0)
+                return signr;
+
+        current->exit_code = 0;
+
+        /* Update the siginfo structure if the signal has
+           changed.  If the debugger wanted something
+           specific in the siginfo structure then it should
+           have updated *info via PTRACE_SETSIGINFO.  */
+        if (signr != info->si_signo) {
+                info->si_signo = signr;
+                info->si_errno = 0;
+                info->si_code = SI_USER;
+                info->si_pid = task_pid_vnr(current->parent);
+                info->si_uid = current->parent->uid;
+        }
+
+        /* If the (new) signal is now blocked, requeue it.  */
+        if (sigismember(&current->blocked, signr)) {
+                specific_send_sig_info(signr, info, current);
+                signr = 0;
+        }
+
+        return signr;
+}
+
 int get_signal_to_deliver(siginfo_t *info, struct k_sigaction *return_ka,
                           struct pt_regs *regs, void *cookie)
 {
@@ -1785,36 +1824,10 @@ relock:
                 if (!signr)
                         break; /* will return 0 */
 
-                if ((current->ptrace & PT_PTRACED) && signr != SIGKILL) {
-                        ptrace_signal_deliver(regs, cookie);
-
-                        /* Let the debugger run.  */
-                        ptrace_stop(signr, 0, info);
-
-                        /* We're back.  Did the debugger cancel the sig?  */
-                        signr = current->exit_code;
-                        if (signr == 0)
-                                continue;
-
-                        current->exit_code = 0;
-
-                        /* Update the siginfo structure if the signal has
-                           changed.  If the debugger wanted something
-                           specific in the siginfo structure then it should
-                           have updated *info via PTRACE_SETSIGINFO.  */
-                        if (signr != info->si_signo) {
-                                info->si_signo = signr;
-                                info->si_errno = 0;
-                                info->si_code = SI_USER;
-                                info->si_pid = task_pid_vnr(current->parent);
-                                info->si_uid = current->parent->uid;
-                        }
-
-                        /* If the (new) signal is now blocked, requeue it.  */
-                        if (sigismember(&current->blocked, signr)) {
-                                specific_send_sig_info(signr, info, current);
+                if (signr != SIGKILL) {
+                        signr = ptrace_signal(signr, info, regs, cookie);
+                        if (!signr)
                                 continue;
-                        }
                 }
 
                 ka = &current->sighand->action[signr-1];