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 C59FEC021A4 for ; Fri, 14 Feb 2025 01:46:06 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 34FC26B0095; Thu, 13 Feb 2025 20:46:06 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 30878280001; Thu, 13 Feb 2025 20:46:06 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1C6A76B0098; Thu, 13 Feb 2025 20:46:06 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id F23B36B0095 for ; Thu, 13 Feb 2025 20:46:05 -0500 (EST) Received: from smtpin29.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 7A264141920 for ; Fri, 14 Feb 2025 01:46:05 +0000 (UTC) X-FDA: 83116859490.29.E08DC02 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by imf08.hostedemail.com (Postfix) with ESMTP id EF10D160004 for ; Fri, 14 Feb 2025 01:46:02 +0000 (UTC) Authentication-Results: imf08.hostedemail.com; dkim=none; spf=pass (imf08.hostedemail.com: domain of tongtiangen@huawei.com designates 45.249.212.255 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=1739497563; 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=/xou2uZRbnImxMqVFANwRB9AlkIaAnGUiupsZKCr/kI=; b=G0ar2aKzKX6ttlF2NmiBBWuIWyX2lTVRZYwOV8LEAu08DHsIvTSZ5go+3HAdf9nI8HXSvj p2wncbR1yvFpjCxR9+ugN6uJ6eYc3S0OfMAxASHXrc8+3ScjijIZVSbCo/8b2nxNpos7Qu exz4TIpx1Aj+XCI1xyEDgNAodLCF/50= ARC-Authentication-Results: i=1; imf08.hostedemail.com; dkim=none; spf=pass (imf08.hostedemail.com: domain of tongtiangen@huawei.com designates 45.249.212.255 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=1739497563; a=rsa-sha256; cv=none; b=NA3UnwbbfEIoTSqjadV0NDPGSXbgTtwUACLgSRX92oZ7UAQ9SjDz65eP318ijV9F14Gvca AdCUvjnLlRIe+DJbxssPVFqtmA/U3xXyt3kC51ri4+dZscG0G8G2D/uTbpbJU1NpXnlR3m Nx2HJZQm8uGQ+sHH5SxNeWx97JG0nD8= Received: from mail.maildlp.com (unknown [172.19.162.254]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4YvFBx5FCVz1W5g8; Fri, 14 Feb 2025 09:41:29 +0800 (CST) Received: from kwepemk500005.china.huawei.com (unknown [7.202.194.90]) by mail.maildlp.com (Postfix) with ESMTPS id CA0DB18032E; Fri, 14 Feb 2025 09:45:58 +0800 (CST) Received: from [10.174.179.234] (10.174.179.234) by kwepemk500005.china.huawei.com (7.202.194.90) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Fri, 14 Feb 2025 09:45:56 +0800 Message-ID: <6aecab97-5ba8-38dd-1df7-87e5f557017e@huawei.com> Date: Fri, 14 Feb 2025 09:45:55 +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 v13 4/5] arm64: support copy_mc_[user]_highpage() To: Catalin Marinas CC: Mark Rutland , Jonathan Cameron , Mauro Carvalho Chehab , 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" , Madhavan Srinivasan , , , , , , , Guohanjun References: <20241209024257.3618492-1-tongtiangen@huawei.com> <20241209024257.3618492-5-tongtiangen@huawei.com> From: Tong Tiangen In-Reply-To: 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 kwepemk500005.china.huawei.com (7.202.194.90) X-Rspamd-Queue-Id: EF10D160004 X-Stat-Signature: ucm4hounp8xarzr3bj313jitwoxz179z X-Rspam-User: X-Rspamd-Server: rspam01 X-HE-Tag: 1739497562-618853 X-HE-Meta: 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 GQOTzNlp +Q8HUKqwLoluOMNmaSTNpFQSKpAbq8LmK+zJUP5ULgd3RHjv+GfKVBN9xt8r34Wwt9GO3JmQuGv+Ex/BG056Ypt3fFEJljs4JsWtdu9O3WcCWLQ26a5zhn6hISv4qgq8NEupzfT0EPX9QwOamClHGkB+6VVIH5QnwH912rMKb9k876m+EKaRQ68IWxTy8fKqq+FWjJerC04kdi2xZZ4WDfwQ+uFqCw7TFsYQQa1msbEgktxAJoXdqSgFjcxt0Qx7Xm1agZ+Px3GnYxFO+5WQefYsHbw== 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: 在 2025/2/13 1:11, Catalin Marinas 写道: > On Mon, Dec 09, 2024 at 10:42:56AM +0800, Tong Tiangen wrote: >> Currently, many scenarios that can tolerate memory errors when copying page >> have been supported in the kernel[1~5], all of which are implemented by >> copy_mc_[user]_highpage(). arm64 should also support this mechanism. >> >> Due to mte, arm64 needs to have its own copy_mc_[user]_highpage() >> architecture implementation, macros __HAVE_ARCH_COPY_MC_HIGHPAGE and >> __HAVE_ARCH_COPY_MC_USER_HIGHPAGE have been added to control it. >> >> Add new helper copy_mc_page() which provide a page copy implementation with >> hardware memory error safe. The code logic of copy_mc_page() is the same as >> copy_page(), the main difference is that the ldp insn of copy_mc_page() >> contains the fixup type EX_TYPE_KACCESS_ERR_ZERO_MEM_ERR, therefore, the >> main logic is extracted to copy_page_template.S. In addition, the fixup of >> MOPS insn is not considered at present. > > Could we not add the exception table entry permanently but ignore the > exception table entry if it's not on the do_sea() path? That would save > some code duplication. The location of the added exception table entry is likely to appear on the a path, which should not be avoided. What we can do is merge duplicate code as much as possible, and extract common code into common files, as we did in this patch. > >> diff --git a/arch/arm64/lib/copy_mc_page.S b/arch/arm64/lib/copy_mc_page.S >> new file mode 100644 >> index 000000000000..51564828c30c >> --- /dev/null >> +++ b/arch/arm64/lib/copy_mc_page.S >> @@ -0,0 +1,37 @@ >> +/* SPDX-License-Identifier: GPL-2.0-only */ >> + >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> + >> +/* >> + * Copy a page from src to dest (both are page aligned) with memory error safe >> + * >> + * Parameters: >> + * x0 - dest >> + * x1 - src >> + * Returns: >> + * x0 - Return 0 if copy success, or -EFAULT if anything goes wrong >> + * while copying. >> + */ >> + .macro ldp1 reg1, reg2, ptr, val >> + KERNEL_MEM_ERR(9998f, ldp \reg1, \reg2, [\ptr, \val]) >> + .endm >> + >> +SYM_FUNC_START(__pi_copy_mc_page) >> +#include "copy_page_template.S" >> + >> + mov x0, #0 >> + ret >> + >> +9998: mov x0, #-EFAULT >> + ret >> + >> +SYM_FUNC_END(__pi_copy_mc_page) >> +SYM_FUNC_ALIAS(copy_mc_page, __pi_copy_mc_page) >> +EXPORT_SYMBOL(copy_mc_page) > [...] >> diff --git a/arch/arm64/lib/copy_page_template.S b/arch/arm64/lib/copy_page_template.S >> new file mode 100644 >> index 000000000000..f96c7988c93d >> --- /dev/null >> +++ b/arch/arm64/lib/copy_page_template.S >> @@ -0,0 +1,70 @@ >> +/* SPDX-License-Identifier: GPL-2.0-only */ >> +/* >> + * Copyright (C) 2012 ARM Ltd. >> + */ >> + >> +/* >> + * Copy a page from src to dest (both are page aligned) >> + * >> + * Parameters: >> + * x0 - dest >> + * x1 - src >> + */ >> + >> +#ifdef CONFIG_AS_HAS_MOPS >> + .arch_extension mops >> +alternative_if_not ARM64_HAS_MOPS >> + b .Lno_mops >> +alternative_else_nop_endif >> + >> + mov x2, #PAGE_SIZE >> + cpypwn [x0]!, [x1]!, x2! >> + cpymwn [x0]!, [x1]!, x2! >> + cpyewn [x0]!, [x1]!, x2! >> + ret >> +.Lno_mops: >> +#endif > [...] > > So if we have FEAT_MOPS, the machine check won't work? > > Kristina is going to post MOPS support for the uaccess routines soon. > You can see how they are wired up and do something similar here. > > But I'd prefer if we had the same code, only the exception table entry > treated differently. Similarly for the MTE tag copying. Does MOPS also support features similar to memory error safe? I'll see how he handles it. >