From patchwork Tue Nov 17 15:47:08 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Andrey Ryabinin X-Patchwork-Id: 7638561 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id D2532BF90C for ; Tue, 17 Nov 2015 15:49:26 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id EC8F9204F6 for ; Tue, 17 Nov 2015 15:49:25 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id BC3F1204E4 for ; Tue, 17 Nov 2015 15:49:24 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZyiTg-0005Vr-1y; Tue, 17 Nov 2015 15:47:28 +0000 Received: from relay.parallels.com ([195.214.232.42]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZyiTc-0005Nj-8r for linux-arm-kernel@lists.infradead.org; Tue, 17 Nov 2015 15:47:25 +0000 Received: from [10.67.48.55] (helo=mail.parallels.net) by relay.parallels.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-SHA384:256) (Exim 4.86) (envelope-from ) id 1ZyiT6-0000Yn-4s; Tue, 17 Nov 2015 18:46:52 +0300 Received: from [10.30.25.228] (10.30.25.228) by MSK-EXCH1.sw.swsoft.com (10.67.48.55) with Microsoft SMTP Server (TLS) id 15.0.1130.7; Tue, 17 Nov 2015 16:46:39 +0100 Subject: Re: [PATCH v7 0/4] KASAN for arm64 To: "Suzuki K. Poulose" References: <1444665180-301-1-git-send-email-ryabinin.a.a@gmail.com> <20151013083432.GG6320@e104818-lin.cambridge.arm.com> <5649BAFD.6030005@arm.com> <5649F783.40109@gmail.com> <564B40A7.1000206@arm.com> From: Andrey Ryabinin Message-ID: <564B4BFC.1020905@virtuozzo.com> Date: Tue, 17 Nov 2015 18:47:08 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.3.0 MIME-Version: 1.0 In-Reply-To: <564B40A7.1000206@arm.com> X-ClientProxiedBy: US-EXCH.sw.swsoft.com (10.255.249.47) To MSK-EXCH1.sw.swsoft.com (10.67.48.55) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20151117_074724_565505_339640B6 X-CRM114-Status: GOOD ( 15.94 ) X-Spam-Score: -4.2 (----) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Yury , Arnd Bergmann , linux-mm@kvack.org, Catalin Marinas , Linus Walleij , Ard Biesheuvel , Will Deacon , linux-kernel@vger.kernel.org, kasan-dev , Alexey Klimov , Alexander Potapenko , Dmitry Vyukov , Andrey Konovalov , David Keitel , linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.8 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP On 11/17/2015 05:58 PM, Suzuki K. Poulose wrote: > On 16/11/15 15:34, Andrey Ryabinin wrote: >> On 11/16/2015 02:16 PM, Suzuki K. Poulose wrote: >>> On 13/10/15 09:34, Catalin Marinas wrote: >>>> On Mon, Oct 12, 2015 at 06:52:56PM +0300, Andrey Ryabinin wrote: > >>> Hi, >>> >>> I get the following failure with KASAN + 16K_PAGES + 48BIT_VA, with 4.4-rc1: >>> >>> >>> arch/arm64/mm/kasan_init.c: In function ‘kasan_early_init’: >>> include/linux/compiler.h:484:38: error: call to ‘__compiletime_assert_95’ declared with attribute error: BUILD_BUG_ON failed: !IS_ALIGNED(KASAN_SHADOW_END, PGDIR_SIZE) >>> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__) >>> ^ > > ... > >> >> Yes, it's really needed, because some code relies on this (e.g. clear_pgs() and kasan_init()). >> But it should be possible to get rid of this requirement. > > And the other important point I missed mentioning was that, my tool chain doesn't > support KASAN. But still the KASAN support files are still compiled and generates > the above error. Shouldn't we disable it at build time if we detect that compiler > doesn't support it ? Something like we do for LSE_ATOMICS. > We should either add proper Kconfig dependency for now, or just make it work. From: Andrey Ryabinin Subject: [PATCH] arm64: KASAN depends on !(ARM64_16K_PAGES && ARM64_VA_BITS_48) On KASAN + 16K_PAGES + 48BIT_VA arch/arm64/mm/kasan_init.c: In function ‘kasan_early_init’: include/linux/compiler.h:484:38: error: call to ‘__compiletime_assert_95’ declared with attribute error: BUILD_BUG_ON failed: !IS_ALIGNED(KASAN_SHADOW_END, PGDIR_SIZE) _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__) Currently KASAN will not work on 16K_PAGES and 48BIT_VA, so forbid such configuration to avoid above build failure. Reported-by: Suzuki K. Poulose Signed-off-by: Andrey Ryabinin Acked-by: Mark Rutland --- arch/arm64/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 9ac16a4..bf7de69 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -49,7 +49,7 @@ config ARM64 select HAVE_ARCH_AUDITSYSCALL select HAVE_ARCH_BITREVERSE select HAVE_ARCH_JUMP_LABEL - select HAVE_ARCH_KASAN if SPARSEMEM_VMEMMAP + select HAVE_ARCH_KASAN if SPARSEMEM_VMEMMAP && !(ARM64_16K_PAGES && ARM64_VA_BITS_48) select HAVE_ARCH_KGDB select HAVE_ARCH_SECCOMP_FILTER select HAVE_ARCH_TRACEHOOK