aboutsummaryrefslogtreecommitdiff
path: root/kernel/signal.c
diff options
context:
space:
mode:
authorJames Bottomley <jejb@mulgrave.il.steeleye.com>2006-06-28 14:06:39 -0400
committerJames Bottomley <jejb@mulgrave.il.steeleye.com>2006-06-28 14:06:39 -0400
commitf28e71617ddaf2483e3e5c5237103484a303743f (patch)
tree67627d2d8ddbf6a4449371e9261d796c013b1fa1 /kernel/signal.c
parentdc6a78f1af10d28fb8c395034ae1e099b85c05b0 (diff)
parenta39727f212426b9d5f9267b3318a2afaf9922d3b (diff)
Merge ../linux-2.6/
Conflicts: drivers/scsi/aacraid/comminit.c Fixed up by removing the now renamed CONFIG_IOMMU option from aacraid Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Diffstat (limited to 'kernel/signal.c')
-rw-r--r--kernel/signal.c35
1 files changed, 30 insertions, 5 deletions
diff --git a/kernel/signal.c b/kernel/signal.c
index 1b3c921737e..52adf53929f 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1531,6 +1531,35 @@ static void do_notify_parent_cldstop(struct task_struct *tsk, int why)
spin_unlock_irqrestore(&sighand->siglock, flags);
}
+static inline int may_ptrace_stop(void)
+{
+ if (!likely(current->ptrace & PT_PTRACED))
+ return 0;
+
+ if (unlikely(current->parent == current->real_parent &&
+ (current->ptrace & PT_ATTACHED)))
+ return 0;
+
+ if (unlikely(current->signal == current->parent->signal) &&
+ unlikely(current->signal->flags & SIGNAL_GROUP_EXIT))
+ return 0;
+
+ /*
+ * Are we in the middle of do_coredump?
+ * If so and our tracer is also part of the coredump stopping
+ * is a deadlock situation, and pointless because our tracer
+ * is dead so don't allow us to stop.
+ * If SIGKILL was already sent before the caller unlocked
+ * ->siglock we must see ->core_waiters != 0. Otherwise it
+ * is safe to enter schedule().
+ */
+ if (unlikely(current->mm->core_waiters) &&
+ unlikely(current->mm == current->parent->mm))
+ return 0;
+
+ return 1;
+}
+
/*
* This must be called with current->sighand->siglock held.
*
@@ -1559,11 +1588,7 @@ static void ptrace_stop(int exit_code, int nostop_code, siginfo_t *info)
spin_unlock_irq(&current->sighand->siglock);
try_to_freeze();
read_lock(&tasklist_lock);
- if (likely(current->ptrace & PT_PTRACED) &&
- likely(current->parent != current->real_parent ||
- !(current->ptrace & PT_ATTACHED)) &&
- (likely(current->parent->signal != current->signal) ||
- !unlikely(current->signal->flags & SIGNAL_GROUP_EXIT))) {
+ if (may_ptrace_stop()) {
do_notify_parent_cldstop(current, CLD_TRAPPED);
read_unlock(&tasklist_lock);
schedule();