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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 36985C54E67 for ; Wed, 27 Mar 2024 00:49:26 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C444D6B0083; Tue, 26 Mar 2024 20:49:25 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id BF4336B0085; Tue, 26 Mar 2024 20:49:25 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id AE3296B0087; Tue, 26 Mar 2024 20:49:25 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 9B3286B0083 for ; Tue, 26 Mar 2024 20:49:25 -0400 (EDT) Received: from smtpin10.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 38A9DC04FA for ; Wed, 27 Mar 2024 00:49:25 +0000 (UTC) X-FDA: 81940985490.10.FC1D579 Received: from szxga07-in.huawei.com (szxga07-in.huawei.com [45.249.212.35]) by imf15.hostedemail.com (Postfix) with ESMTP id 91362A0008 for ; Wed, 27 Mar 2024 00:49:22 +0000 (UTC) Authentication-Results: imf15.hostedemail.com; dkim=none; spf=pass (imf15.hostedemail.com: domain of tongtiangen@huawei.com designates 45.249.212.35 as permitted sender) smtp.mailfrom=tongtiangen@huawei.com; dmarc=pass (policy=quarantine) header.from=huawei.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1711500563; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=MOGh0OIshJmiRYXyqQp6r2abD5mmF5F7Pq7DepjyS5M=; b=KEWVt10iQ3d7ZG+UcXvTA82v+e0VfupMOfpq4sWCpWxM4wS1MOO/4J870WZCNhtfK/t9r1 yNHrFwZrlguJ7FmJw3la39caL8vge2gDguYpftiNpWnHH53rFzfCUxNeP8PJy418wx8ZXr PBc+zd7L2BgM+KJzHyfacycIk77nbac= ARC-Authentication-Results: i=1; imf15.hostedemail.com; dkim=none; spf=pass (imf15.hostedemail.com: domain of tongtiangen@huawei.com designates 45.249.212.35 as permitted sender) smtp.mailfrom=tongtiangen@huawei.com; dmarc=pass (policy=quarantine) header.from=huawei.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1711500563; a=rsa-sha256; cv=none; b=2X/s8zPDxZD4KFQMNvus9xS6AEWtMEofWPtLqhnVIK0WSRCjhUnueS5rnmPIzUOWyH8qdr tV3hjVXFbO4IO09ewudncI5w9JYOGuITQyecDnKV/H5e3p6DDg9T3PoI7eB6uKpJq/ff4s GaSIELNEWcifnk1LMCNn73IPkgjf6p0= Received: from mail.maildlp.com (unknown [172.19.163.44]) by szxga07-in.huawei.com (SkyGuard) with ESMTP id 4V47KC2BFCz1R7Kc; Wed, 27 Mar 2024 08:46:39 +0800 (CST) Received: from kwepemm600017.china.huawei.com (unknown [7.193.23.234]) by mail.maildlp.com (Postfix) with ESMTPS id C7ADC140412; Wed, 27 Mar 2024 08:49:18 +0800 (CST) Received: from [10.174.179.234] (10.174.179.234) by kwepemm600017.china.huawei.com (7.193.23.234) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.35; Wed, 27 Mar 2024 08:49:16 +0800 Message-ID: <54007f91-3614-37c2-49f6-fc30429ec67d@huawei.com> Date: Wed, 27 Mar 2024 08:49:16 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.8.0 Subject: Re: [PATCH v11 0/5]arm64: add ARCH_HAS_COPY_MC support To: Mark Rutland , Catalin Marinas , Will Deacon , Andrew Morton , James Morse , Robin Murphy , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , Michael Ellerman , Nicholas Piggin , Andrey Ryabinin , Alexander Potapenko , Christophe Leroy , Aneesh Kumar K.V , "Naveen N. Rao" , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , , "H. Peter Anvin" CC: , , , , , Guohanjun References: <20240207132204.1720444-1-tongtiangen@huawei.com> From: Tong Tiangen In-Reply-To: <20240207132204.1720444-1-tongtiangen@huawei.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.174.179.234] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To kwepemm600017.china.huawei.com (7.193.23.234) X-Rspamd-Queue-Id: 91362A0008 X-Rspam-User: X-Stat-Signature: q5c1iutzomqwczbu1c91ki8o7c15m1kr X-Rspamd-Server: rspam01 X-HE-Tag: 1711500562-319760 X-HE-Meta: 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 HqYO5jxK 4fICts29xFZiTZaWMErZiX3R1g7BSFFXbZDrEWysc9xXcsWWF/AiV91wFertg1pfCTAxIep51xMO2UhcGz/+9aPC9dUU5bYPvDVClmiBrKKYlWdgEX+Iek0AwbMRzYm/V2QwQqM2RS8r7ykuK05txQ+eOaJOs1uQVJe7bO9eUbVYQCRHp4E4/SqzudN+hUKRbX8VgpJxgca6LohTfPewuIg7PNAAqthbYCjLmIXzFE1aFJwdGrxZtSp+WnlCMunLGOzeLcQEa2sio3BMbZ1qv3mtmiskDgIiTjWCfoBU2b/34ivF0BY+ArhCJJ55r9A5f3s9KNLO67pl1sqZ3oPBebE/0Jk50T/Ei6HokfvHCRneRE7qPbGrk6Hn2qWBELGpArkAY 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: List-Subscribe: List-Unsubscribe: Hi Mark: Kindly ping... Thanks, Tong. 在 2024/2/7 21:21, Tong Tiangen 写道: > With the increase of memory capacity and density, the probability of memory > error also increases. The increasing size and density of server RAM in data > centers and clouds have shown increased uncorrectable memory errors. > > Currently, more and more scenarios that can tolerate memory errors，such as > CoW[1,2], KSM copy[3], coredump copy[4], khugepaged[5,6], uaccess copy[7], > etc. > > This patchset introduces a new processing framework on ARM64, which enables > ARM64 to support error recovery in the above scenarios, and more scenarios > can be expanded based on this in the future. > > In arm64, memory error handling in do_sea(), which is divided into two cases: > 1. If the user state consumed the memory errors, the solution is to kill > the user process and isolate the error page. > 2. If the kernel state consumed the memory errors, the solution is to > panic. > > For case 2, Undifferentiated panic may not be the optimal choice, as it can > be handled better. In some scenarios, we can avoid panic, such as uaccess, > if the uaccess fails due to memory error, only the user process will be > affected, killing the user process and isolating the user page with > hardware memory errors is a better choice. > > [1] commit d302c2398ba2 ("mm, hwpoison: when copy-on-write hits poison, take page offline") > [2] commit 1cb9dc4b475c ("mm: hwpoison: support recovery from HugePage copy-on-write faults") > [3] commit 6b970599e807 ("mm: hwpoison: support recovery from ksm_might_need_to_copy()") > [4] commit 245f09226893 ("mm: hwpoison: coredump: support recovery from dump_user_range()") > [5] commit 98c76c9f1ef7 ("mm/khugepaged: recover from poisoned anonymous memory") > [6] commit 12904d953364 ("mm/khugepaged: recover from poisoned file-backed memory") > [7] commit 278b917f8cb9 ("x86/mce: Add _ASM_EXTABLE_CPY for copy user access") > > ------------------ > Test result: > > 1. copy_page(), copy_mc_page() basic function test pass, and the disassembly > contents remains the same before and after refactor. > > 2. copy_to/from_user() access kernel NULL pointer raise translation fault > and dump error message then die(), test pass. > > 3. Test following scenarios: copy_from_user(), get_user(), COW. > > Before patched: trigger a hardware memory error then panic. > After patched: trigger a hardware memory error without panic. > > Testing step: > step1. start an user-process. > step2. poison(einj) the user-process's page. > step3: user-process access the poison page in kernel mode, then trigger SEA. > step4: the kernel will not panic, only the user process is killed, the poison > page is isolated. (before patched, the kernel will panic in do_sea()) > > ------------------ > > Since V10: > Accroding Mark's suggestion: > 1. Merge V10's patch2 and patch3 to V11's patch2. > 2. Patch2(V11): use new fixup_type for ld* in copy_to_user(), fix fatal > issues (NULL kernel pointeraccess) been fixup incorrectly. > 3. Patch2(V11): refactoring the logic of do_sea(). > 4. Patch4(V11): Remove duplicate assembly logic and remove do_mte(). > > Besides: > 1. Patch2(V11): remove st* insn's fixup, st* generally not trigger memory error. > 2. Split a part of the logic of patch2(V11) to patch5(V11), for detail, > see patch5(V11)'s commit msg. > 3. Remove patch6(v10) “arm64: introduce copy_mc_to_kernel() implementation”. > During modification, some problems that cannot be solved in a short > period are found. The patch will be released after the problems are > solved. > 4. Add test result in this patch. > 5. Modify patchset title, do not use machine check and remove "-next". > > Since V9: > 1. Rebase to latest kernel version 6.8-rc2. > 2. Add patch 6/6 to support copy_mc_to_kernel(). > > Since V8: > 1. Rebase to latest kernel version and fix topo in some of the patches. > 2. According to the suggestion of Catalin, I attempted to modify the > return value of function copy_mc_[user]_highpage() to bytes not copied. > During the modification process, I found that it would be more > reasonable to return -EFAULT when copy error occurs (referring to the > newly added patch 4). > > For ARM64, the implementation of copy_mc_[user]_highpage() needs to > consider MTE. Considering the scenario where data copying is successful > but the MTE tag copying fails, it is also not reasonable to return > bytes not copied. > 3. Considering the recent addition of machine check safe support for > multiple scenarios, modify commit message for patch 5 (patch 4 for V8). > > Since V7: > Currently, there are patches supporting recover from poison > consumption for the cow scenario[1]. Therefore, Supporting cow > scenario under the arm64 architecture only needs to modify the relevant > code under the arch/. > [1]https://lore.kernel.org/lkml/20221031201029.102123-1-tony.luck@intel.com/ > > Since V6: > Resend patches that are not merged into the mainline in V6. > > Since V5: > 1. Add patch2/3 to add uaccess assembly helpers. > 2. Optimize the implementation logic of arm64_do_kernel_sea() in patch8. > 3. Remove kernel access fixup in patch9. > All suggestion are from Mark. > > Since V4: > 1. According Michael's suggestion, add patch5. > 2. According Mark's suggestiog, do some restructuring to arm64 > extable, then a new adaptation of machine check safe support is made based > on this. > 3. According Mark's suggestion, support machine check safe in do_mte() in > cow scene. > 4. In V4, two patches have been merged into -next, so V5 not send these > two patches. > > Since V3: > 1. According to Robin's suggestion, direct modify user_ldst and > user_ldp in asm-uaccess.h and modify mte.S. > 2. Add new macro USER_MC in asm-uaccess.h, used in copy_from_user.S > and copy_to_user.S. > 3. According to Robin's suggestion, using micro in copy_page_mc.S to > simplify code. > 4. According to KeFeng's suggestion, modify powerpc code in patch1. > 5. According to KeFeng's suggestion, modify mm/extable.c and some code > optimization. > > Since V2: > 1. According to Mark's suggestion, all uaccess can be recovered due to > memory error. > 2. Scenario pagecache reading is also supported as part of uaccess > (copy_to_user()) and duplication code problem is also solved. > Thanks for Robin's suggestion. > 3. According Mark's suggestion, update commit message of patch 2/5. > 4. According Borisllav's suggestion, update commit message of patch 1/5. > > Since V1: > 1.Consistent with PPC/x86, Using CONFIG_ARCH_HAS_COPY_MC instead of > ARM64_UCE_KERNEL_RECOVERY. > 2.Add two new scenes, cow and pagecache reading. > 3.Fix two small bug(the first two patch). > > V1 in here: > https://lore.kernel.org/lkml/20220323033705.3966643-1-tongtiangen@huawei.com/ > > Tong Tiangen (5): > uaccess: add generic fallback version of copy_mc_to_user() > arm64: add support for ARCH_HAS_COPY_MC > mm/hwpoison: return -EFAULT when copy fail in > copy_mc_[user]_highpage() > arm64: support copy_mc_[user]_highpage() > arm64: send SIGBUS to user process for SEA exception > > arch/arm64/Kconfig | 1 + > arch/arm64/include/asm/asm-extable.h | 31 ++++++++++++--- > arch/arm64/include/asm/asm-uaccess.h | 4 ++ > arch/arm64/include/asm/extable.h | 1 + > arch/arm64/include/asm/mte.h | 9 +++++ > arch/arm64/include/asm/page.h | 10 +++++ > arch/arm64/lib/Makefile | 2 + > arch/arm64/lib/copy_mc_page.S | 37 ++++++++++++++++++ > arch/arm64/lib/copy_page.S | 50 +++---------------------- > arch/arm64/lib/copy_page_template.S | 56 ++++++++++++++++++++++++++++ > arch/arm64/lib/copy_to_user.S | 10 ++--- > arch/arm64/lib/mte.S | 29 ++++++++++++++ > arch/arm64/mm/copypage.c | 45 ++++++++++++++++++++++ > arch/arm64/mm/extable.c | 19 ++++++++++ > arch/arm64/mm/fault.c | 39 ++++++++++++++----- > arch/powerpc/include/asm/uaccess.h | 1 + > arch/x86/include/asm/uaccess.h | 1 + > include/linux/highmem.h | 16 ++++++-- > include/linux/uaccess.h | 9 +++++ > mm/khugepaged.c | 4 +- > 20 files changed, 304 insertions(+), 70 deletions(-) > create mode 100644 arch/arm64/lib/copy_mc_page.S > create mode 100644 arch/arm64/lib/copy_page_template.S >