From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5C312D515; Mon, 29 Sep 2025 18:03:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.40.44.14 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759169035; cv=none; b=A9+hcRkkDDHr5ViNY9vHkx1S003mqZGy7M/uG0NjmT0fDiwkUJRBVkgaDRRnsNI4cqED+Mr7MYkc1T8XgnNfFlrP4ha0GHFhKNz4XWqN40QLR2HXQswRZM1PBI9+SGPdrqyX+vuZHnYSK6O4BU/5JwgeayezYX/YqDQautepGUE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759169035; c=relaxed/simple; bh=4JNuSJOTgcqgADV7Gk0XfDIZ5uP1/840vUsuwrTd/rE=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=I2ifkGBbbJ+yz0rDMJpE7OtsJG7OKUu9Eb3i1z3hLytfeqeZU7khTGQGRtZ4Vm3iqq00gjdCGK/PO/bMfO/FKm3IYGcDgJE2uwYwC/olnUWuqAVHhvKAJDRfN8U0wXvswGn5vKg9NIks46J8qdq/dU/2ZKWKiyMsQw3qfuanuaU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org; spf=pass smtp.mailfrom=goodmis.org; arc=none smtp.client-ip=216.40.44.14 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=goodmis.org Received: from omf13.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id B0D8958FC3; Mon, 29 Sep 2025 18:03:44 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf13.hostedemail.com (Postfix) with ESMTPA id 3181A20010; Mon, 29 Sep 2025 18:03:37 +0000 (UTC) Date: Mon, 29 Sep 2025 14:03:24 -0400 From: Steven Rostedt To: Sasha Levin Cc: mhiramat@kernel.org, mathieu.desnoyers@efficios.com, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: Re: [PATCH] tracing: Fix lock imbalance in s_start() memory allocation failure path Message-ID: <20250929140230.79c06c22@batman.local.home> In-Reply-To: <20250929113238.3722055-1-sashal@kernel.org> References: <20250929113238.3722055-1-sashal@kernel.org> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Stat-Signature: a9m4zx4hdiskugwjbh8aowfj94ur5zsy X-Rspamd-Server: rspamout08 X-Rspamd-Queue-Id: 3181A20010 X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX18LYf/Wb1G9qPbi3TegXCerr1JJD8iwULo= X-HE-Tag: 1759169017-732405 X-HE-Meta: U2FsdGVkX1+ImKxOT1IRIqCobmj8OGl67EHo1K2L+759126duQT83kDAgJKgHlvaq5fmbAftds9qLowDuPOnPGBugIDeKvF2Ox+hUijbZSXZtF6xg1wqYZArUrmE1vVw+jHIR4JZrnN5zxLQXW7mwmFqE4iU8d++aWs+n3Bo/uY/CuC3sGSVmKdfPdSBE01E957TZ94UnVh6pXCAoU02j0WeKvBQFUTe0ozqOT7jpN+AWvK3+idXxcaWzYLzd54vPfZaAwydFLcUY3MFMGoNYgzzgocj68yhvXyCy9YVZGcx7JUnZl47SxHkVGDg1xeRqkQ9ns04jkZ0z1GiW43jPoGUpTjpC9vv On Mon, 29 Sep 2025 07:32:38 -0400 Sasha Levin wrote: > iff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c > index 9f3e9537417d5..e00da4182deb7 100644 > --- a/kernel/trace/trace_events.c > +++ b/kernel/trace/trace_events.c > @@ -1629,11 +1629,10 @@ static void *s_start(struct seq_file *m, loff_t *pos) > loff_t l; > > iter = kzalloc(sizeof(*iter), GFP_KERNEL); > + mutex_lock(&event_mutex); > if (!iter) > return NULL; > > - mutex_lock(&event_mutex); > - > iter->type = SET_EVENT_FILE; > iter->file = list_entry(&tr->events, struct trace_event_file, list); > Good catch, thanks! -- Steve