From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 C44542288D5; Sun, 9 Aug 2026 02:32:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786242737; cv=none; b=TTxBjp+islt7JzDA80ViL09ouRctsImXcwY8jMXvAm4F4MFKcpJ1JQRMumUbBvAODoWpNZdbpcAAecIVcfb1ZFRaO7gTrWhdSXH3GrJP9/Ejk+aCR+MGFMoX1L/2Z1L4+T3swAdwziE/aGoLxkPWSxmKotKGgRpWgK9T7IQVoE4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786242737; c=relaxed/simple; bh=YNR0P/zFuUV7bXFyQhPjlznSIw0c98m1qcxNvY1hGMw=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=nfyJTYJtCcEK6Asp2ubm16ZLCHWm5lccPsI2v5FBSqSlOxYkCg8sWmqU4EY3q7JlADYK02HButZR/58cIaS+p5Yzt1o9cHWKNDlII3cOCd/ww/d00EPz/Kr4p3c0CxhojSkBoflooTojH8IFHqudK8EVCLM/XQ46Mvs7YKnVvZs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=C0BBPO/7; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="C0BBPO/7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 82C471F00ACF; Sun, 9 Aug 2026 02:32:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1786242735; bh=fxBXChhYmXgLyv5TgSo4dJdJjV7r0PgcnZo4WSFSkcg=; h=Date:From:To:Cc:Subject:References; b=C0BBPO/7Okfh+zHRr4IJlqcW4JbMGUl8TfDB64PVKCm+RPAh6H5FtQqKZ3yzWcxY6 OzOkeGNQxUjEyPxWQ+GHSdeornZVSz8FIYg1R4TyR+NlgTekIveYi3RbWkfY4uUgTu jSa+0idfynVNgr7VqqpFaxNpEZFFOEKwkuTJ+NPB7E/g26pCIYP15IuVxXVyYfuSZ0 ZAyZfJ28Xaz2/e+HRbmlZtiYMdyfDGU+6fBfcEbYsivhzBgZ6vcDRZ1gkoG+F11RME cWBTV0xyhR90BlCG1GYybbcorNMO9YpMb/Wl0tA3hg+7NiUn1alDrXahApE82UU+h5 q9OoJMLhIl/Gg== Received: from rostedt by gandalf with local (Exim 4.99.4) (envelope-from ) id 1wstKn-00000001N3j-3VY5; Sat, 08 Aug 2026 22:32:21 -0400 Message-ID: <20260809023221.693441329@kernel.org> User-Agent: quilt/0.69 Date: Sat, 08 Aug 2026 22:31:47 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , stable@vger.kernel.org, Jiri Olsa , Leon Hwang Subject: [for-linus][PATCH 03/12] ftrace: Protect direct_functions in ftrace_find_rec_direct References: <20260809023144.852271250@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 From: Leon Hwang Fix accessing the __rcu pointer direct_functions with RCU protection. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260730150411.88667-2-leon.hwang@linux.dev Fixes: d05cb470663a ("ftrace: Fix modification of direct_function hash while in use") Acked-by: Jiri Olsa Suggested-by: Steven Rostedt Signed-off-by: Leon Hwang Signed-off-by: Steven Rostedt --- kernel/trace/ftrace.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 6c47a94f5924..c5d1d0d42ccc 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -2645,7 +2645,8 @@ unsigned long ftrace_find_rec_direct(unsigned long ip) { struct ftrace_func_entry *entry; - entry = __ftrace_lookup_ip(direct_functions, ip); + guard(preempt_notrace)(); + entry = __ftrace_lookup_ip(rcu_dereference_sched(direct_functions), ip); if (!entry) return 0; -- 2.53.0