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 4105AC7618E for ; Fri, 21 Apr 2023 14:31:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232606AbjDUObL (ORCPT ); Fri, 21 Apr 2023 10:31:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38478 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232598AbjDUObI (ORCPT ); Fri, 21 Apr 2023 10:31:08 -0400 Received: from out4-smtp.messagingengine.com (out4-smtp.messagingengine.com [66.111.4.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B21604695 for ; Fri, 21 Apr 2023 07:31:04 -0700 (PDT) Received: from compute6.internal (compute6.nyi.internal [10.202.2.47]) by mailout.nyi.internal (Postfix) with ESMTP id 376595C0180; Fri, 21 Apr 2023 10:31:01 -0400 (EDT) Received: from imap51 ([10.202.2.101]) by compute6.internal (MEProxy); Fri, 21 Apr 2023 10:31:01 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arndb.de; h=cc :cc:content-type:content-type:date:date:from:from:in-reply-to :in-reply-to:message-id:mime-version:references:reply-to:sender :subject:subject:to:to; s=fm2; t=1682087461; x=1682173861; bh=ob qkcphqvBdAWuMSyr9Pl64QwA+BGq6GX8P7IjRDFMo=; b=adXBOo68IWWVLNpbR7 XTdrYX6QuvQtcqZzG0y/PGRna4nQkqxhvCmx2PFZw6E8HQhvBu8YuttxyxSeSwmt ex3Z8HKdsMA+j33afFwRg1nUycgXXA9EqjHi2WZbF+2zKud1Si1vIJ9RICQ4tbfC fnBuHmL8nvKEOJE3I8Jp4Ak3hAV2oQHDymVGThGr8FhAEuuZ8OYkvMuJ7O2JFKR5 61MOoRcj70iYHQtZjoLADZpOyenXjL1B752TDuQTVAkKJuutL/kYXRtgTyzLiuYO r/3orOzFknrsWAJ64W4Qqj2gVy7C/Q3rjyVGNiirlJNrOD8BzaN/IJmtY2JybRly tteQ== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-type:content-type:date:date :feedback-id:feedback-id:from:from:in-reply-to:in-reply-to :message-id:mime-version:references:reply-to:sender:subject :subject:to:to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender :x-sasl-enc; s=fm3; t=1682087461; x=1682173861; bh=obqkcphqvBdAW uMSyr9Pl64QwA+BGq6GX8P7IjRDFMo=; b=gNB50BU/CdGiEojWS7vu5BksyMRZd OlxJEOs2ueNsgZUeagQpaCifJONqnXMRnNeXZ6WBeKFmDIdMq4gSwOyWpABT7YFM 82ikp6ZGLZZlXE0mogvyi6m5dIoTqSwRwPdWOleGwlFzLpKxBtKT8QYAaOaOn2ay zLkZep1hHmwlYSP0323Av4Tl5sxfLJN7WPGEIKvc/xlT2rPrJvN0YvtvpmMU2nJM 6uMowFldG2kBh0dbwY1H/Q/Je/FvqMi+bMxS56HN7G/l8maGNXq2hWeVXZ36FBVn oV3/p9Pr70otk+PnhfcjOCRo192dRUX38z06ZOZscgQsIfHFBEoLKmPGg== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvhedrfedtgedgjeeiucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne cujfgurhepofgfggfkjghffffhvfevufgtsehttdertderredtnecuhfhrohhmpedftehr nhguuceuvghrghhmrghnnhdfuceorghrnhgusegrrhhnuggsrdguvgeqnecuggftrfgrth htvghrnhepffehueegteeihfegtefhjefgtdeugfegjeelheejueethfefgeeghfektdek teffnecuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehmrghilhhfrhhomheprg hrnhgusegrrhhnuggsrdguvg X-ME-Proxy: Feedback-ID: i56a14606:Fastmail Received: by mailuser.nyi.internal (Postfix, from userid 501) id 65915B60086; Fri, 21 Apr 2023 10:31:00 -0400 (EDT) X-Mailer: MessagingEngine.com Webmail Interface User-Agent: Cyrus-JMAP/3.9.0-alpha0-372-g43825cb665-fm-20230411.003-g43825cb6 Mime-Version: 1.0 Message-Id: <5d13e927-3713-4b9e-b007-6be5671d46f2@app.fastmail.com> In-Reply-To: <20230421130111.4041641-1-tudor.ambarus@linaro.org> References: <20230421130111.4041641-1-tudor.ambarus@linaro.org> Date: Fri, 21 Apr 2023 16:30:40 +0200 From: "Arnd Bergmann" To: "Tudor Ambarus" , "Nathan Chancellor" , "Nick Desaulniers" , "Tom Rix" , "Andrew Morton" Cc: joneslee@google.com, "Peter Zijlstra" , "Kees Cook" , "Josh Poimboeuf" , zhaoyang.huang@unisoc.com, "Liam R. Howlett" , "Randy Dunlap" , "Geert Uytterhoeven" , linux-kernel@vger.kernel.org, llvm@lists.linux.dev, "Mark Brown" , "Dmitry Vyukov" , nogikh@google.com Subject: Re: [PATCH] Kconfig.debug: disable CONFIG_FRAME_WARN for KASAN_STACK && CC_IS_CLANG by default Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Apr 21, 2023, at 15:01, Tudor Ambarus wrote: > The conclusion is that when KASAN is enabled the stack usage increases a > bit, but nothing unmanageable ~30-70 bytes, whereas when enabling > KASAN_STACK the stack usage is excessive, from ~1.7K to ~5.8K for these > cases. > > Disable CONFIG_FRAME_WARN for KASAN_STACK && CC_IS_CLANG by default. > Adventurers can still override the default value by input prompt or > explicit values in defconfigs in case they feel that some real warnings > are missed. > > Signed-off-by: Tudor Ambarus I think we are still better off with the warning enabled. When someone really wants to run a kernel with KASAN_STACK enabled, they should have a chance to see what they are getting into and not report any runtime bugs that come from stack overflow. Arnd