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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_PASS 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 A7E3EC282CB for ; Tue, 5 Feb 2019 11:30:15 +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 590B920821 for ; Tue, 5 Feb 2019 11:30:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 590B920821 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 43v2S52hzQzDqKN for ; Tue, 5 Feb 2019 22:30:13 +1100 (AEDT) Received: from ozlabs.org (bilbo.ozlabs.org [203.11.71.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 43v2Ly2M8lzDqHm for ; Tue, 5 Feb 2019 22:25:46 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Received: by ozlabs.org (Postfix, from userid 1034) id 43v2Ly0LH2z9sMx; Tue, 5 Feb 2019 22:25:45 +1100 (AEDT) X-powerpc-patch-notification: thanks X-powerpc-patch-commit: 579b9239c1f38665b21e8d0e6ee83ecc96dbd6bb X-Patchwork-Hint: ignore In-Reply-To: <20190123062138.22644-1-aneesh.kumar@linux.ibm.com> To: "Aneesh Kumar K.V" , npiggin@gmail.com, benh@kernel.crashing.org, paulus@samba.org From: Michael Ellerman Subject: Re: arch/powerpc/radix: Fix kernel crash with mremap Message-Id: <43v2Ly0LH2z9sMx@ozlabs.org> Date: Tue, 5 Feb 2019 22:25:45 +1100 (AEDT) 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: "Aneesh Kumar K.V" , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Wed, 2019-01-23 at 06:21:38 UTC, "Aneesh Kumar K.V" wrote: > With support for split pmd lock, we use pmd page pmd_huge_pte pointer to store > the deposited page table. In those config when we move page tables we need to > make sure we move the depoisted page table to the right pmd page. Otherwise this > can result in crash when we withdraw of deposited page table because we can find > the pmd_huge_pte NULL. > > c0000000004a1230 __split_huge_pmd+0x1070/0x1940 > c0000000004a0ff4 __split_huge_pmd+0xe34/0x1940 (unreliable) > c0000000004a4000 vma_adjust_trans_huge+0x110/0x1c0 > c00000000042fe04 __vma_adjust+0x2b4/0x9b0 > c0000000004316e8 __split_vma+0x1b8/0x280 > c00000000043192c __do_munmap+0x13c/0x550 > c000000000439390 sys_mremap+0x220/0x7e0 > c00000000000b488 system_call+0x5c/0x70 > > Fixes: 675d995297d4 ("powerpc/book3s64: Enable split pmd ptlock.") > Signed-off-by: Aneesh Kumar K.V > Signed-off-by: Aneesh Kumar K.V Applied to powerpc fixes, thanks. https://git.kernel.org/powerpc/c/579b9239c1f38665b21e8d0e6ee83ecc cheers