Attachment 180921 Details for Bug 232837 – Roland's fix.

[patch] Roland's fix.

bz232837c10.patch (text/plain), 2.01 KB, created by Jan Kratochvil on 2007-08-30 12:30:39 UTC

(hide)

Description:

Filename:

MIME Type:

Creator: Jan Kratochvil

Created: 2007-08-30 12:30:39 UTC

Size: 2.01 KB

patch

obsolete

>
>diff --git a/kernel/utrace.c b/kernel/utrace.c
>index 056596a..0000000 100644  
>--- a/kernel/utrace.c
>+++ b/kernel/utrace.c
>@@ -977,7 +977,7 @@ utrace_set_flags(struct task_struct *tar
> {
> 	struct utrace *utrace;
> 	int report;
>-	unsigned long old_flags, old_utrace_flags;
>+	unsigned long old_flags, old_utrace_flags, set_utrace_flags;
> 	int ret = -EALREADY;
> 
> #ifdef ARCH_HAS_SINGLE_STEP
>@@ -1011,6 +1011,22 @@ restart:			/* See below. */
> 	}
> 
> 	/*
>+	 * When it's in TASK_STOPPED state, do not set UTRACE_EVENT(JCTL).
>+	 * That bit indicates utrace_report_jctl has not run yet and so the
>+	 * target cannot be considered quiescent.  But if the bit wasn't
>+	 * already set, it can't be in running in there and really is
>+	 * quiescent now in its existing job control stop.  We set
>+	 * UTRACE_ACTION_QUIESCE to be sure that once it resumes it will
>+	 * recompute its flags in utrace_quiescent.
>+	 */
>+	set_utrace_flags = flags;
>+	if (((set_utrace_flags &~ old_utrace_flags) & UTRACE_EVENT(JCTL))
>+	    && target->state == TASK_STOPPED) {
>+		set_utrace_flags &= ~UTRACE_EVENT(JCTL);
>+		set_utrace_flags |= UTRACE_ACTION_QUIESCE;
>+	}
>+
>+	/*
> 	 * When setting these flags, it's essential that we really
> 	 * synchronize with exit_notify.  They cannot be set after
> 	 * exit_notify takes the tasklist_lock.  By holding the read
>@@ -1020,20 +1036,20 @@ restart:			/* See below. */
> 	 * knows positively that utrace_report_death will be called or
> 	 * that it won't.
> 	 */
>-	if ((flags &~ old_utrace_flags) & (UTRACE_ACTION_NOREAP
>-					   | DEATH_EVENTS)) {
>+	if ((set_utrace_flags &~ old_utrace_flags) & (UTRACE_ACTION_NOREAP
>+						      | DEATH_EVENTS)) {
> 		read_lock(&tasklist_lock);
> 		if (unlikely(target->exit_state)) {
> 			read_unlock(&tasklist_lock);
> 			spin_unlock(&utrace->lock);
> 			return ret;
> 		}
>-		target->utrace_flags |= flags;
>+		target->utrace_flags |= set_utrace_flags;
> 		read_unlock(&tasklist_lock);
> 	}
> 
> 	engine->flags = flags;
>-	target->utrace_flags |= flags;
>+	target->utrace_flags |= set_utrace_flags;
> 	ret = 0;
> 
> 	report = 0;

Actions: View | Diff

Attachments on bug 232837: 150336 | 150448 | 150449 | 150476 | 180921