Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

Pull core signal handling updates from Eric Biederman:
 "It was observed that a periodic timer in combination with a
  sufficiently expensive fork could prevent fork from every completing.
  This contains the changes to remove the need for that restart.

  This set of changes is split into several parts:

   - The first part makes PIDTYPE_TGID a proper pid type instead
     something only for very special cases. The part starts using
     PIDTYPE_TGID enough so that in __send_signal where signals are
     actually delivered we know if the signal is being sent to a a group
     of processes or just a single process.

   - With that prep work out of the way the logic in fork is modified so
     that fork logically makes signals received while it is running
     appear to be received after the fork completes"

* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (22 commits)
  signal: Don't send signals to tasks that don't exist
  signal: Don't restart fork when signals come in.
  fork: Have new threads join on-going signal group stops
  fork: Skip setting TIF_SIGPENDING in ptrace_init_task
  signal: Add calculate_sigpending()
  fork: Unconditionally exit if a fatal signal is pending
  fork: Move and describe why the code examines PIDNS_ADDING
  signal: Push pid type down into complete_signal.
  signal: Push pid type down into __send_signal
  signal: Push pid type down into send_signal
  signal: Pass pid type into do_send_sig_info
  signal: Pass pid type into send_sigio_to_task & send_sigurg_to_task
  signal: Pass pid type into group_send_sig_info
  signal: Pass pid and pid type into send_sigqueue
  posix-timers: Noralize good_sigevent
  signal: Use PIDTYPE_TGID to clearly store where file signals will be sent
  pid: Implement PIDTYPE_TGID
  pids: Move the pgrp and session pid pointers from task_struct to signal_struct
  kvm: Don't open code task_pid in kvm_vcpu_ioctl
  pids: Compute task_tgid using signal->leader_pid
  ...

1 files changed, 8 insertions, 5 deletions

diff --git a/init/init_task.c b/init/init_task.c
index 74f60baa2799..5aebe3be4d7c 100644
--- a/init/init_task.c
+++ b/init/init_task.c
@@ -22,6 +22,7 @@ static struct signal_struct init_signals = {
 		.list = LIST_HEAD_INIT(init_signals.shared_pending.list),
 		.signal =  {{0}}
 	},
+	.multiprocess	= HLIST_HEAD_INIT,
 	.rlim		= INIT_RLIMITS,
 	.cred_guard_mutex = __MUTEX_INITIALIZER(init_signals.cred_guard_mutex),
 #ifdef CONFIG_POSIX_TIMERS
@@ -33,6 +34,12 @@ static struct signal_struct init_signals = {
 	},
 #endif
 	INIT_CPU_TIMERS(init_signals)
+	.pids = {
+		[PIDTYPE_PID]	= &init_struct_pid,
+		[PIDTYPE_TGID]	= &init_struct_pid,
+		[PIDTYPE_PGID]	= &init_struct_pid,
+		[PIDTYPE_SID]	= &init_struct_pid,
+	},
 	INIT_PREV_CPUTIME(init_signals)
 };
 
@@ -111,11 +118,7 @@ struct task_struct init_task
 	INIT_CPU_TIMERS(init_task)
 	.pi_lock	= __RAW_SPIN_LOCK_UNLOCKED(init_task.pi_lock),
 	.timer_slack_ns = 50000, /* 50 usec default slack */
-	.pids = {
-		[PIDTYPE_PID]  = INIT_PID_LINK(PIDTYPE_PID),
-		[PIDTYPE_PGID] = INIT_PID_LINK(PIDTYPE_PGID),
-		[PIDTYPE_SID]  = INIT_PID_LINK(PIDTYPE_SID),
-	},
+	.thread_pid	= &init_struct_pid,
 	.thread_group	= LIST_HEAD_INIT(init_task.thread_group),
 	.thread_node	= LIST_HEAD_INIT(init_signals.thread_head),
 #ifdef CONFIG_AUDITSYSCALL