From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3F9C2C41535 for ; Mon, 15 Nov 2021 23:47:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 36C8861BE2 for ; Mon, 15 Nov 2021 23:47:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1356306AbhKOXtj (ORCPT ); Mon, 15 Nov 2021 18:49:39 -0500 Received: from mail.kernel.org ([198.145.29.99]:45126 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344202AbhKOTYG (ORCPT ); Mon, 15 Nov 2021 14:24:06 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id CD6986363E; Mon, 15 Nov 2021 18:53:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1637002424; bh=hQC/tPsuiKxKWLs0oPZJ0cAQWOa9ot7MTebF7yuPSD4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Z+vm0hlW+IyglsGbdIyUGtauw+QtCMfL2JmGCVEsLBYkzu9t3GGpoG3wFPrJ7CGLH vPzesn5jLjpxwI/hWPQGN3OjJpkDfGTd9yVrMVTIscSJLlGtPnLWZDU9kSMjmdTPG3 NiGu3thNIFnOs+mSP64muyAGXgQHhvIErdW00U+8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Stephen Rothwell , "Peter Zijlstra (Intel)" , Kees Cook , Sasha Levin Subject: [PATCH 5.15 528/917] x86: Fix __get_wchan() for !STACKTRACE Date: Mon, 15 Nov 2021 18:00:23 +0100 Message-Id: <20211115165446.664604795@linuxfoundation.org> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211115165428.722074685@linuxfoundation.org> References: <20211115165428.722074685@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Peter Zijlstra [ Upstream commit 5d1ceb3969b6b2e47e2df6d17790a7c5a20fcbb4 ] Use asm/unwind.h to implement wchan, since we cannot always rely on STACKTRACE=y. Fixes: bc9bbb81730e ("x86: Fix get_wchan() to support the ORC unwinder") Reported-by: Stephen Rothwell Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Kees Cook Link: https://lkml.kernel.org/r/20211022152104.137058575@infradead.org Signed-off-by: Sasha Levin --- arch/x86/kernel/process.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index 266962547b58c..2fe1810e922a9 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -43,6 +43,7 @@ #include #include #include +#include #include "process.h" @@ -945,10 +946,20 @@ unsigned long arch_randomize_brk(struct mm_struct *mm) */ unsigned long __get_wchan(struct task_struct *p) { - unsigned long entry = 0; + struct unwind_state state; + unsigned long addr = 0; - stack_trace_save_tsk(p, &entry, 1, 0); - return entry; + for (unwind_start(&state, p, NULL, NULL); !unwind_done(&state); + unwind_next_frame(&state)) { + addr = unwind_get_return_address(&state); + if (!addr) + break; + if (in_sched_functions(addr)) + continue; + break; + } + + return addr; } long do_arch_prctl_common(struct task_struct *task, int option, -- 2.33.0