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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1CD18C433FE for ; Tue, 11 Oct 2022 18:44:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229913AbiJKSoz (ORCPT ); Tue, 11 Oct 2022 14:44:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51540 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229729AbiJKSot (ORCPT ); Tue, 11 Oct 2022 14:44:49 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CB64D101F8; Tue, 11 Oct 2022 11:44:48 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 93E9DB81662; Tue, 11 Oct 2022 18:44:47 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id F1BB2C433C1; Tue, 11 Oct 2022 18:44:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1665513886; bh=kyayna2rlKwjfKz02ltMfVPHv/rzSWgj6SiEFuUd3Nk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=lcOgczNVxlQkjCzCBLAG3UNJBsyD42k4fQ57YqXCGNm5o3VBL1fTh+k/Jhs+qdprT VBcYBtZbhau7BKtbdt12etSMYilzfu38GRWK4DjIY2NZxmxCa/IC91EdJM6vUdlbXP jYv/i0Ya7FeWEjfW995xvNkofbNQLU7JMoBpAtg7kmrIYb7mX7ZmjzdJqP7TzfYeDW 7Ds5iDkq4+G+kEVZiFGIpvRCGQ/1CYEWZNPX7ihTW4Rh9Js44lbZ73W0/zBoo5Yhfh 9edTUsWHTCLAnwTf5RkPe9/y676IHOSEuJaPEiKKXWkF/G/wwwunemD5HLr+Fp8Bej AkyJhXKxswZ6w== Date: Tue, 11 Oct 2022 11:44:44 -0700 From: Josh Poimboeuf To: Peter Zijlstra Cc: Linus Torvalds , Andrew Morton , Alexander Potapenko , Andrey Konovalov , mm-commits@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [GIT PULL] MM updates for 6.1-rc1 Message-ID: <20221011184444.npthr2pmzqb32x6z@treble> References: <20221008132113.919b9b894426297de78ac00f@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Oct 11, 2022 at 10:24:27AM +0200, Peter Zijlstra wrote: > On Mon, Oct 10, 2022 at 06:20:00PM -0700, Linus Torvalds wrote: > > The other thing I notice from just doing a build is that I now get > > > > vmlinux.o: warning: objtool: kasan_report+0x12: call to > > stackleak_track_stack() with UACCESS enabled > > So kasan_report() is already marked as being special; and it does the > mandatory user_access_save() / user_access_restore() things to fix it > up. > > But it looks like kasan code itself is now getting instrumented by the > stackleak stuff and that inserts a call outside of the > user_access_save()/restore() thing, and *that* is getting flagged. > > Looking at mm/kasan/Makefile it disables a lot of the instrumentation, > but perhaps not enough? I can recreate, but weirdly the below doesn't seem to fix it. diff --git a/mm/kasan/Makefile b/mm/kasan/Makefile index d4837bff3b60..a41cf1235032 100644 --- a/mm/kasan/Makefile +++ b/mm/kasan/Makefile @@ -1,5 +1,6 @@ # SPDX-License-Identifier: GPL-2.0 KASAN_SANITIZE := n +KMSAN_SANITIZE := n UBSAN_SANITIZE := n KCOV_INSTRUMENT := n