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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 4ED18C433E0 for ; Sat, 30 May 2020 17:24:18 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0788920723 for ; Sat, 30 May 2020 17:24:17 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0788920723 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=csgroup.eu Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 49Z7b36vPszDqXM for ; Sun, 31 May 2020 03:24:15 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=csgroup.eu (client-ip=93.17.236.30; helo=pegase1.c-s.fr; envelope-from=christophe.leroy@csgroup.eu; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=csgroup.eu Received: from pegase1.c-s.fr (pegase1.c-s.fr [93.17.236.30]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 49Z7YF2MvBzDqfv for ; Sun, 31 May 2020 03:22:39 +1000 (AEST) Received: from localhost (mailhub1-int [192.168.12.234]) by localhost (Postfix) with ESMTP id 49Z7Y64FKHzB09b6; Sat, 30 May 2020 19:22:34 +0200 (CEST) X-Virus-Scanned: Debian amavisd-new at c-s.fr Received: from pegase1.c-s.fr ([192.168.12.234]) by localhost (pegase1.c-s.fr [192.168.12.234]) (amavisd-new, port 10024) with ESMTP id oBdg8nh7GnbL; Sat, 30 May 2020 19:22:34 +0200 (CEST) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase1.c-s.fr (Postfix) with ESMTP id 49Z7Y62k5CzB09b5; Sat, 30 May 2020 19:22:34 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id B0A798B7B1; Sat, 30 May 2020 19:22:36 +0200 (CEST) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id PZJBAGeee5Vz; Sat, 30 May 2020 19:22:36 +0200 (CEST) Received: from [192.168.4.90] (unknown [192.168.4.90]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 5A9AD8B75E; Sat, 30 May 2020 19:22:36 +0200 (CEST) Subject: Re: [PATCH] powerpc/32: disable KASAN with pages bigger than 16k From: Christophe Leroy To: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman References: <7195fcde7314ccbf7a081b356084a69d421b10d4.1590660977.git.christophe.leroy@csgroup.eu> Message-ID: Date: Sat, 30 May 2020 19:22:28 +0200 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.8.1 MIME-Version: 1.0 In-Reply-To: <7195fcde7314ccbf7a081b356084a69d421b10d4.1590660977.git.christophe.leroy@csgroup.eu> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: fr Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Le 28/05/2020 à 12:17, Christophe Leroy a écrit : > Mapping of early shadow area is implemented by using a single static > page table having all entries pointing to the same early shadow page. > The shadow area must therefore occupy full PGD entries. > > The shadow area has a size of 128Mbytes starting at 0xf8000000. > With 4k pages, a PGD entry is 4Mbytes > With 16k pages, a PGD entry is 64Mbytes > With 64k pages, a PGD entry is 256Mbytes which is too big. That's for 32k pages that a PGD is 256Mbytes. With 64k pages, a PGD entry is 1Gbytes which is too big. Michael, can you fix the commit log ? Thanks Christophe > > Until we rework the early shadow mapping, disable KASAN when the > page size is too big. > > Reported-by: kbuild test robot > Fixes: 2edb16efc899 ("powerpc/32: Add KASAN support") > Cc: stable@vger.kernel.org > Signed-off-by: Christophe Leroy > --- > arch/powerpc/Kconfig | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig > index 1dfa59126fcf..066b36bf9efa 100644 > --- a/arch/powerpc/Kconfig > +++ b/arch/powerpc/Kconfig > @@ -169,8 +169,8 @@ config PPC > select HAVE_ARCH_AUDITSYSCALL > select HAVE_ARCH_HUGE_VMAP if PPC_BOOK3S_64 && PPC_RADIX_MMU > select HAVE_ARCH_JUMP_LABEL > - select HAVE_ARCH_KASAN if PPC32 > - select HAVE_ARCH_KASAN_VMALLOC if PPC32 > + select HAVE_ARCH_KASAN if PPC32 && PPC_PAGE_SHIFT <= 14 > + select HAVE_ARCH_KASAN_VMALLOC if PPC32 && PPC_PAGE_SHIFT <= 14 > select HAVE_ARCH_KGDB > select HAVE_ARCH_MMAP_RND_BITS > select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT >