7 files changed, 13 insertions, 44 deletions

diff --git a/kernel/acct.c b/kernel/acct.c
index dd68b9059418..f6006a60df5d 100644
--- a/kernel/acct.c
+++ b/kernel/acct.c
@@ -548,7 +548,7 @@ static void do_acct_process(struct bsd_acct_struct *acct,
 #endif
 
         spin_lock_irq(&current->sighand->siglock);
-        tty = current->signal->tty;
+        tty = current->signal->tty;     /* Safe as we hold the siglock */
         ac.ac_tty = tty ? old_encode_dev(tty_devnum(tty)) : 0;
         ac.ac_utime = encode_comp_t(jiffies_to_AHZ(cputime_to_jiffies(pacct->ac_utime)));
         ac.ac_stime = encode_comp_t(jiffies_to_AHZ(cputime_to_jiffies(pacct->ac_stime)));
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 59cedfb040e7..cf5bc2f5f9c3 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -246,8 +246,8 @@ static int audit_match_perm(struct audit_context *ctx, int mask)
         unsigned n;
         if (unlikely(!ctx))
                 return 0;
-
         n = ctx->major;
+
         switch (audit_classify_syscall(ctx->arch, n)) {
         case 0: /* native */
                 if ((mask & AUDIT_PERM_WRITE) &&
@@ -1204,13 +1204,13 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts
                                  (context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
                                  context->return_code);
 
-        mutex_lock(&tty_mutex);
-        read_lock(&tasklist_lock);
+        spin_lock_irq(&tsk->sighand->siglock);
         if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name)
                 tty = tsk->signal->tty->name;
         else
                 tty = "(none)";
-        read_unlock(&tasklist_lock);
+        spin_unlock_irq(&tsk->sighand->siglock);
+
         audit_log_format(ab,
                   " a0=%lx a1=%lx a2=%lx a3=%lx items=%d"
                   " ppid=%d pid=%d auid=%u uid=%u gid=%u"
@@ -1230,7 +1230,6 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts
                   context->egid, context->sgid, context->fsgid, tty,
                   tsk->sessionid);
 
-        mutex_unlock(&tty_mutex);
 
         audit_log_task_info(ab, tsk);
         if (context->filterkey) {
diff --git a/kernel/fork.c b/kernel/fork.c
index 7ce2ebe84796..30de644a40c4 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -802,6 +802,7 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
 
         sig->leader = 0;        /* session leadership doesn't inherit */
         sig->tty_old_pgrp = NULL;
+        sig->tty = NULL;
 
         sig->utime = sig->stime = sig->cutime = sig->cstime = cputime_zero;
         sig->gtime = cputime_zero;
@@ -838,6 +839,7 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
 void __cleanup_signal(struct signal_struct *sig)
 {
         exit_thread_group_keys(sig);
+        tty_kref_put(sig->tty);
         kmem_cache_free(signal_cachep, sig);
 }
 
@@ -1227,7 +1229,8 @@ static struct task_struct *copy_process(unsigned long clone_flags,
                                 p->nsproxy->pid_ns->child_reaper = p;
 
                         p->signal->leader_pid = pid;
-                        p->signal->tty = current->signal->tty;
+                        tty_kref_put(p->signal->tty);
+                        p->signal->tty = tty_kref_get(current->signal->tty);
                         set_task_pgrp(p, task_pgrp_nr(current));
                         set_task_session(p, task_session_nr(current));
                         attach_pid(p, PIDTYPE_PGID, task_pgrp(current));
diff --git a/kernel/printk.c b/kernel/printk.c
index b51b1567bb55..a430fd04008b 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -1291,22 +1291,6 @@ static int __init disable_boot_consoles(void)
 }
 late_initcall(disable_boot_consoles);
 
-/**
- * tty_write_message - write a message to a certain tty, not just the console.
- * @tty: the destination tty_struct
- * @msg: the message to write
- *
- * This is used for messages that need to be redirected to a specific tty.
- * We don't put it into the syslog queue right now maybe in the future if
- * really needed.
- */
-void tty_write_message(struct tty_struct *tty, char *msg)
-{
-        if (tty && tty->ops->write)
-                tty->ops->write(tty, msg, strlen(msg));
-        return;
-}
-
 #if defined CONFIG_PRINTK
 
 /*
diff --git a/kernel/sched_debug.c b/kernel/sched_debug.c
index bbe6b31c3c56..ad958c1ec708 100644
--- a/kernel/sched_debug.c
+++ b/kernel/sched_debug.c
@@ -333,12 +333,10 @@ void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
         unsigned long flags;
         int num_threads = 1;
 
-        rcu_read_lock();
         if (lock_task_sighand(p, &flags)) {
                 num_threads = atomic_read(&p->signal->count);
                 unlock_task_sighand(p, &flags);
         }
-        rcu_read_unlock();
 
         SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, p->pid, num_threads);
         SEQ_printf(m,
diff --git a/kernel/sys.c b/kernel/sys.c
index 038a7bc0901d..234d9454294e 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1060,9 +1060,7 @@ asmlinkage long sys_setsid(void)
         group_leader->signal->leader = 1;
         __set_special_pids(sid);
 
-        spin_lock(&group_leader->sighand->siglock);
-        group_leader->signal->tty = NULL;
-        spin_unlock(&group_leader->sighand->siglock);
+        proc_clear_tty(group_leader);
 
         err = session;
 out:
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 50ec0886fa3d..c468c3c6dfc5 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -80,7 +80,6 @@ extern int pid_max_min, pid_max_max;
 extern int sysctl_drop_caches;
 extern int percpu_pagelist_fraction;
 extern int compat_log;
-extern int maps_protect;
 extern int latencytop_enabled;
 extern int sysctl_nr_open_min, sysctl_nr_open_max;
 #ifdef CONFIG_RCU_TORTURE_TEST
@@ -118,10 +117,8 @@ extern char modprobe_path[];
 extern int sg_big_buff;
 #endif
 
-#ifdef __sparc__
-extern char reboot_command [];
-extern int stop_a_enabled;
-extern int scons_pwroff;
+#ifdef CONFIG_SPARC
+#include <asm/system.h>
 #endif
 
 #ifdef __hppa__
@@ -415,7 +412,7 @@ static struct ctl_table kern_table[] = {
                 .mode           = 0644,
                 .proc_handler   = &proc_dointvec,
         },
-#ifdef __sparc__
+#ifdef CONFIG_SPARC
         {
                 .ctl_name       = KERN_SPARC_REBOOT,
                 .procname       = "reboot-cmd",
@@ -810,16 +807,6 @@ static struct ctl_table kern_table[] = {
                 .proc_handler   = &proc_dointvec,
         },
 #endif
-#ifdef CONFIG_PROC_FS
-        {
-                .ctl_name       = CTL_UNNUMBERED,
-                .procname       = "maps_protect",
-                .data           = &maps_protect,
-                .maxlen         = sizeof(int),
-                .mode           = 0644,
-                .proc_handler   = &proc_dointvec,
-        },
-#endif
         {
                 .ctl_name       = CTL_UNNUMBERED,
                 .procname       = "poweroff_cmd",