Merge remote-tracking branch 'asoc/fix/rt5645' into asoc-fix-rt5645

1 files changed, 49 insertions, 21 deletions

diff --git a/kernel/fork.c b/kernel/fork.c
index 1bfefc6f96a4..7d5f0f118a63 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -287,6 +287,11 @@ static void set_max_threads(unsigned int max_threads_suggested)
         max_threads = clamp_t(u64, threads, MIN_THREADS, MAX_THREADS);
 }
 
+#ifdef CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT
+/* Initialized by the architecture: */
+int arch_task_struct_size __read_mostly;
+#endif
+
 void __init fork_init(void)
 {
 #ifndef CONFIG_ARCH_TASK_STRUCT_ALLOCATOR
@@ -295,7 +300,7 @@ void __init fork_init(void)
 #endif
         /* create a slab on which task_structs can be allocated */
         task_struct_cachep =
-                kmem_cache_create("task_struct", sizeof(struct task_struct),
+                kmem_cache_create("task_struct", arch_task_struct_size,
                         ARCH_MIN_TASKALIGN, SLAB_PANIC | SLAB_NOTRACK, NULL);
 #endif
 
@@ -449,8 +454,9 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm)
                 tmp->vm_mm = mm;
                 if (anon_vma_fork(tmp, mpnt))
                         goto fail_nomem_anon_vma_fork;
-                tmp->vm_flags &= ~VM_LOCKED;
+                tmp->vm_flags &= ~(VM_LOCKED|VM_UFFD_MISSING|VM_UFFD_WP);
                 tmp->vm_next = tmp->vm_prev = NULL;
+                tmp->vm_userfaultfd_ctx = NULL_VM_UFFD_CTX;
                 file = tmp->vm_file;
                 if (file) {
                         struct inode *inode = file_inode(file);
@@ -1067,6 +1073,7 @@ static int copy_sighand(unsigned long clone_flags, struct task_struct *tsk)
         rcu_assign_pointer(tsk->sighand, sig);
         if (!sig)
                 return -ENOMEM;
+
         atomic_set(&sig->count, 1);
         memcpy(sig->action, current->sighand->action, sizeof(sig->action));
         return 0;
@@ -1128,6 +1135,7 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
         init_sigpending(&sig->shared_pending);
         INIT_LIST_HEAD(&sig->posix_timers);
         seqlock_init(&sig->stats_lock);
+        prev_cputime_init(&sig->prev_cputime);
 
         hrtimer_init(&sig->real_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
         sig->real_timer.function = it_real_fn;
@@ -1239,6 +1247,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 {
         int retval;
         struct task_struct *p;
+        void *cgrp_ss_priv[CGROUP_CANFORK_COUNT] = {};
 
         if ((clone_flags & (CLONE_NEWNS|CLONE_FS)) == (CLONE_NEWNS|CLONE_FS))
                 return ERR_PTR(-EINVAL);
@@ -1273,10 +1282,9 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 
         /*
          * If the new process will be in a different pid or user namespace
-         * do not allow it to share a thread group or signal handlers or
-         * parent with the forking task.
+         * do not allow it to share a thread group with the forking task.
          */
-        if (clone_flags & CLONE_SIGHAND) {
+        if (clone_flags & CLONE_THREAD) {
                 if ((clone_flags & (CLONE_NEWUSER | CLONE_NEWPID)) ||
                     (task_active_pid_ns(current) !=
                                 current->nsproxy->pid_ns_for_children))
@@ -1335,9 +1343,8 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 
         p->utime = p->stime = p->gtime = 0;
         p->utimescaled = p->stimescaled = 0;
-#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
-        p->prev_cputime.utime = p->prev_cputime.stime = 0;
-#endif
+        prev_cputime_init(&p->prev_cputime);
+
 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
         seqlock_init(&p->vtime_seqlock);
         p->vtime_snap = 0;
@@ -1513,6 +1520,16 @@ static struct task_struct *copy_process(unsigned long clone_flags,
         p->task_works = NULL;
 
         /*
+         * Ensure that the cgroup subsystem policies allow the new process to be
+         * forked. It should be noted the the new process's css_set can be changed
+         * between here and cgroup_post_fork() if an organisation operation is in
+         * progress.
+         */
+        retval = cgroup_can_fork(p, cgrp_ss_priv);
+        if (retval)
+                goto bad_fork_free_pid;
+
+        /*
          * Make it visible to the rest of the system, but dont wake it up yet.
          * Need tasklist lock for parent etc handling!
          */
@@ -1548,7 +1565,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
                 spin_unlock(&current->sighand->siglock);
                 write_unlock_irq(&tasklist_lock);
                 retval = -ERESTARTNOINTR;
-                goto bad_fork_free_pid;
+                goto bad_fork_cancel_cgroup;
         }
 
         if (likely(p->pid)) {
@@ -1590,7 +1607,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
         write_unlock_irq(&tasklist_lock);
 
         proc_fork_connector(p);
-        cgroup_post_fork(p);
+        cgroup_post_fork(p, cgrp_ss_priv);
         if (clone_flags & CLONE_THREAD)
                 threadgroup_change_end(current);
         perf_event_fork(p);
@@ -1600,6 +1617,8 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 
         return p;
 
+bad_fork_cancel_cgroup:
+        cgroup_cancel_fork(p, cgrp_ss_priv);
 bad_fork_free_pid:
         if (pid != &init_struct_pid)
                 free_pid(pid);
@@ -1866,13 +1885,21 @@ static int check_unshare_flags(unsigned long unshare_flags)
                                 CLONE_NEWUSER|CLONE_NEWPID))
                 return -EINVAL;
         /*
-         * Not implemented, but pretend it works if there is nothing to
-         * unshare. Note that unsharing CLONE_THREAD or CLONE_SIGHAND
-         * needs to unshare vm.
+         * Not implemented, but pretend it works if there is nothing
+         * to unshare.  Note that unsharing the address space or the
+         * signal handlers also need to unshare the signal queues (aka
+         * CLONE_THREAD).
          */
         if (unshare_flags & (CLONE_THREAD | CLONE_SIGHAND | CLONE_VM)) {
-                /* FIXME: get_task_mm() increments ->mm_users */
-                if (atomic_read(&current->mm->mm_users) > 1)
+                if (!thread_group_empty(current))
+                        return -EINVAL;
+        }
+        if (unshare_flags & (CLONE_SIGHAND | CLONE_VM)) {
+                if (atomic_read(&current->sighand->count) > 1)
+                        return -EINVAL;
+        }
+        if (unshare_flags & CLONE_VM) {
+                if (!current_is_single_threaded())
                         return -EINVAL;
         }
 
@@ -1936,21 +1963,22 @@ SYSCALL_DEFINE1(unshare, unsigned long, unshare_flags)
         int err;
 
         /*
-         * If unsharing a user namespace must also unshare the thread.
+         * If unsharing a user namespace must also unshare the thread group
+         * and unshare the filesystem root and working directories.
          */
         if (unshare_flags & CLONE_NEWUSER)
                 unshare_flags |= CLONE_THREAD | CLONE_FS;
         /*
-         * If unsharing a thread from a thread group, must also unshare vm.
-         */
-        if (unshare_flags & CLONE_THREAD)
-                unshare_flags |= CLONE_VM;
-        /*
          * If unsharing vm, must also unshare signal handlers.
          */
         if (unshare_flags & CLONE_VM)
                 unshare_flags |= CLONE_SIGHAND;
         /*
+         * If unsharing a signal handlers, must also unshare the signal queues.
+         */
+        if (unshare_flags & CLONE_SIGHAND)
+                unshare_flags |= CLONE_THREAD;
+        /*
          * If unsharing namespace, must also unshare filesystem information.
          */
         if (unshare_flags & CLONE_NEWNS)