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 X-Spam-Level: X-Spam-Status: No, score=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5F638C43381 for ; Mon, 18 Feb 2019 10:44:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 35FF82147A for ; Mon, 18 Feb 2019 10:44:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730288AbfBRKoE (ORCPT ); Mon, 18 Feb 2019 05:44:04 -0500 Received: from foss.arm.com ([217.140.101.70]:55932 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728258AbfBRKoE (ORCPT ); Mon, 18 Feb 2019 05:44:04 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0717C80D; Mon, 18 Feb 2019 02:44:04 -0800 (PST) Received: from fuggles.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 5D2B73F720; Mon, 18 Feb 2019 02:44:02 -0800 (PST) Date: Mon, 18 Feb 2019 10:43:59 +0000 From: Will Deacon To: Qian Cai Cc: rostedt@goodmis.org, mingo@redhat.com, catalin.marinas@arm.com, andreyknvl@google.com, aryabinin@virtuozzo.com, linux-arm-kernel@lists.infradead.org, kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH] trace: skip hwasan Message-ID: <20190218104359.GB10743@fuggles.cambridge.arm.com> References: <20190217043434.46233-1-cai@lca.pw> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190217043434.46233-1-cai@lca.pw> User-Agent: Mutt/1.11.1+86 (6f28e57d73f2) () Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Feb 16, 2019 at 11:34:34PM -0500, Qian Cai wrote: > Enabling function tracer with CONFIG_KASAN_SW_TAGS=y (hwasan) tracer > causes the whole system frozen on ThunderX2 systems with 256 CPUs, > because there is a burst of too much pointer access, and then KASAN will > dereference each byte of the shadow address for the tag checking which > will kill all the CPUs. > > Signed-off-by: Qian Cai > --- > kernel/trace/Makefile | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile > index c2b2148bb1d2..fdd547a68385 100644 > --- a/kernel/trace/Makefile > +++ b/kernel/trace/Makefile > @@ -28,6 +28,11 @@ ifdef CONFIG_GCOV_PROFILE_FTRACE > GCOV_PROFILE := y > endif > > +# Too much pointer access will kill hwasan. > +ifdef CONFIG_KASAN_SW_TAGS > +KASAN_SANITIZE := n > +endif I don't maintain this file, but I think that my comments on your related patch are relevant here as well: https://lkml.org/lkml/2019/2/18/223 Will