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=-11.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL autolearn=no 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 D5856C282DD for ; Wed, 8 Jan 2020 15:31:51 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 9793120673 for ; Wed, 8 Jan 2020 15:31:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="PF1EOmb3" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9793120673 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 32A8E8E0005; Wed, 8 Jan 2020 10:31:51 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 3022B8E0001; Wed, 8 Jan 2020 10:31:51 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 217DA8E0005; Wed, 8 Jan 2020 10:31:51 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0166.hostedemail.com [216.40.44.166]) by kanga.kvack.org (Postfix) with ESMTP id 08E668E0001 for ; Wed, 8 Jan 2020 10:31:51 -0500 (EST) Received: from smtpin05.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with SMTP id BDB8B181AC9B6 for ; Wed, 8 Jan 2020 15:31:50 +0000 (UTC) X-FDA: 76354857180.05.gold75_4a41b30f29c01 X-HE-Tag: gold75_4a41b30f29c01 X-Filterd-Recvd-Size: 5706 Received: from mail-wr1-f65.google.com (mail-wr1-f65.google.com [209.85.221.65]) by imf10.hostedemail.com (Postfix) with ESMTP for ; Wed, 8 Jan 2020 15:31:50 +0000 (UTC) Received: by mail-wr1-f65.google.com with SMTP id j42so3771397wrj.12 for ; Wed, 08 Jan 2020 07:31:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=QkB3h7LR7Kpj+7Idz89WGGG390skSZe9d57uSxB5V4E=; b=PF1EOmb3VmEEBmRD6W58mTKF/DW4wP3zbxvdxl0y1hVt685psfzkh7rVG7ep3bolfY 244fRzcm38wSRGJ2sc5dxa3DeeMCfIG1HV3sJCalXHoyZS9LuMFzlHLRrcKSLiwKT+yI TZXljpAsRGWHj/vNIMOSjT9lXUSYXS8nXPrrWL8kx186jfG2663zZxtksDKOhaSE+oyQ p4ugDYuPvH5/qViMc40rYkBQxybBxvXVrkfoT35o6xzp7t25vJfZLAmhEsHlnZBPoWVN pbf4Pqr/bEzDqWqE+3u6hyB/MHoES11GKujgFSM2tChbwNLINZ08v6qvIiVaTWr03ndq pwpw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=QkB3h7LR7Kpj+7Idz89WGGG390skSZe9d57uSxB5V4E=; b=Eq6M1aPXu3oNxPRcJSgkgZgWsrjus/aZy2VsZ9MNjFpwe9PfSoAWf9wLaX36jDGcqF 7HyBD16nBXy3u5YfNS61Psf8I1IWrgt94+Zb47gp/HAZD8y0gCQ8QQHmfQaPB8YGwlWB 1ausW3eOTZ/TIUrBxlM6RH9xg0S0x9NeILNLzLK/DcaWzD1zQF0c8BA3hsswdSSj+2kO GGoGWPxH5uz4xSPWmlpR+sAAM8G5qdx2RlZSyHC8PMAfig8ZqIXOHcSrk/RZo0fnNT9D nQxJnpkAKyfd94xljFc8fhBtksr2BT2yDsgbpu5KbX/8jQsj9spElMvlC8su1OLa7/W8 e1EQ== X-Gm-Message-State: APjAAAW+cqvx6knJqS1T1AXh4WstuJwMxFf5uYW13y7AvsTkG4UhgHkE IXn11HxqLxiKYIm3EtqykSImqHX0bf9kBcpAMRY/bA== X-Google-Smtp-Source: APXvYqy+Xhu4zW9KM1ygYi89hEng3ygnVKDwOvnOm4hOl2gxk9wtQejQm8BAeXwaoZ5VBGAk0ole1kjAUr0bhf32bWc= X-Received: by 2002:adf:806e:: with SMTP id 101mr5478874wrk.300.1578497508734; Wed, 08 Jan 2020 07:31:48 -0800 (PST) MIME-Version: 1.0 References: <20191220184955.223741-1-glider@google.com> <20191220184955.223741-21-glider@google.com> In-Reply-To: From: Alexander Potapenko Date: Wed, 8 Jan 2020 16:31:35 +0100 Message-ID: Subject: Re: [PATCH RFC v4 20/42] kmsan: x86: increase stack sizes in KMSAN builds To: Arnd Bergmann Cc: Jens Axboe , Andy Lutomirski , Vegard Nossum , Dmitry Vyukov , Marco Elver , Andrey Konovalov , Christoph Hellwig , Linux-MM , Al Viro , Andreas Dilger , Andrew Morton , Andrey Ryabinin , Ard Biesheuvel , Christoph Hellwig , "Darrick J. Wong" , David Miller , Dmitry Torokhov , Eric Biggers , Eric Dumazet , Eric Van Hensbergen , gregkh , Harry Wentland , Herbert Xu , Ilya Leoshkevich , Ingo Molnar , Jason Wang , Marek Szyprowski , Mark Rutland , "Martin K. Petersen" , Martin Schwidefsky , Matthew Wilcox , "Michael S. Tsirkin" , Michal Hocko , Michal Simek , Petr Mladek , Qian Cai , Randy Dunlap , Robin Murphy , Sergey Senozhatsky , Steven Rostedt , Takashi Iwai , "Theodore Ts'o" , Thomas Gleixner , Vasily Gorbik , Wolfram Sang Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Dec 30, 2019 at 6:39 PM Arnd Bergmann wrote: > > On Sun, Dec 22, 2019 at 2:25 PM wrote: > > > > KMSAN instruments the code heavily, increasing register pressure and > > preventing functions from being inlined. As a result, the kernel > > requires more stack space to run. > > > > Rename KASAN_STACK_ORDER to EXTRA_STACK_ORDER and set EXTRA_STACK_ORDER > > to 2 for KMSAN builds, effectively making the stacks 4 times larger. > > > > Signed-off-by: Alexander Potapenko > > What about CONFIG_FRAME_WARN? Do you need to change that as well to get > a warning-free build? If so, what is the minimum value that you need? Right now my config only yields a single warning about a frame of 2056 byte= s. Actually, KMSAN tends to have even smaller frames than KASAN, so making the stacks so big might be too heavy-handed. I'll look into decreasing the stack sizes. --=20 Alexander Potapenko Software Engineer Google Germany GmbH Erika-Mann-Stra=C3=9Fe, 33 80636 M=C3=BCnchen Gesch=C3=A4ftsf=C3=BChrer: Paul Manicle, Halimah DeLaine Prado Registergericht und -nummer: Hamburg, HRB 86891 Sitz der Gesellschaft: Hamburg