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 5854BE81DF4 for ; Fri, 6 Oct 2023 13:02:37 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id DC8918E0021; Fri, 6 Oct 2023 09:02:36 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D79568E000B; Fri, 6 Oct 2023 09:02:36 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C41068E0021; Fri, 6 Oct 2023 09:02:36 -0400 (EDT) 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 B4D1B8E000B for ; Fri, 6 Oct 2023 09:02:36 -0400 (EDT) Received: from smtpin07.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 91122807D8 for ; Fri, 6 Oct 2023 13:02:35 +0000 (UTC) X-FDA: 81315050670.07.7A4D80B Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by imf26.hostedemail.com (Postfix) with ESMTP id A938F140042 for ; Fri, 6 Oct 2023 13:02:31 +0000 (UTC) Authentication-Results: imf26.hostedemail.com; dkim=none; spf=pass (imf26.hostedemail.com: domain of jonathan.cameron@huawei.com designates 185.176.79.56 as permitted sender) smtp.mailfrom=jonathan.cameron@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=1696597352; 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=zp4ZjDO1bS3hmWWTHWyIFeuezZe6kCt8B9WY16JfNPQ=; b=UhR+/j06CfGWBA/PckShXAMreoq6AsoTszNCSUHQKiLOwq1v/Nmr0Pf5iJbb/UNJ6yDXz6 XqMaxzSJVKf56WRcj09ta2hAiEzdR17txIMmOvJAOj9g9vjLFueukWxRozX+YGYuPgJEJd f2cd8RrZB/v3unopuIAwzu/0sejovuY= ARC-Authentication-Results: i=1; imf26.hostedemail.com; dkim=none; spf=pass (imf26.hostedemail.com: domain of jonathan.cameron@huawei.com designates 185.176.79.56 as permitted sender) smtp.mailfrom=jonathan.cameron@huawei.com; dmarc=pass (policy=quarantine) header.from=huawei.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1696597352; a=rsa-sha256; cv=none; b=b0yYo/O1dCdnIt2aXZjLz51NyCtQUiRW8CAAh8+hYoKaImFCsoXnk8WFvwkGL0NQxb+i9C 2w4yq7hBgUjqqcoQ3bsprD1FwD13osB99hJRkgQmth9tl9U6NkfWkN+HOmft5Cpf3VAtUT J/gTe9ut85NrUDMrKRqOlPPFWy9oUNQ= Received: from lhrpeml500005.china.huawei.com (unknown [172.18.147.226]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4S27qm2Qp6z6K6wd; Fri, 6 Oct 2023 21:02:12 +0800 (CST) Received: from localhost (10.202.227.76) by lhrpeml500005.china.huawei.com (7.191.163.240) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Fri, 6 Oct 2023 14:02:25 +0100 Date: Fri, 6 Oct 2023 14:02:24 +0100 From: Jonathan Cameron To: David Rientjes CC: Jiaqi Yan , "Luck, Tony" , "Grimm, Jon" , , , , , , , , , , , , , , , , , , , , , Subject: Re: [RFC PATCH 2/9] memory: scrub: sysfs: Add Documentation entries for set of scrub attributes Message-ID: <20231006140224.000018a2@Huawei.com> In-Reply-To: <92f48c1c-3235-49b2-aabd-7da87ad3febc@google.com> References: <20230915172818.761-1-shiju.jose@huawei.com> <20230915172818.761-3-shiju.jose@huawei.com> <20230922111740.000046d7@huawei.com> <92f48c1c-3235-49b2-aabd-7da87ad3febc@google.com> Organization: Huawei Technologies Research and Development (UK) Ltd. X-Mailer: Claws Mail 4.1.0 (GTK 3.24.33; x86_64-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.202.227.76] X-ClientProxiedBy: lhrpeml100003.china.huawei.com (7.191.160.210) To lhrpeml500005.china.huawei.com (7.191.163.240) X-CFilter-Loop: Reflected X-Rspamd-Queue-Id: A938F140042 X-Rspam-User: X-Stat-Signature: kwi38syaszg7khg3prhchcjz9w39btpa X-Rspamd-Server: rspam01 X-HE-Tag: 1696597351-397511 X-HE-Meta: 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 YdPuD1FI iW03cQ8nF0R7qnsqDbMZQy+nCcqRWunNbOB+kFZG010sUxd7hIYCpAC4K8NKtud4va5GhNDC+72nTNM9w4ctXp+71OWQIOa9T96UQoTrh1b6z2+NSg5rSDnYAKP52+OZjErCQ2Rp6fqHzMqxLPjKE6Vf0wUjblLgGxwMn+vjO7LqpeKo2wiMRlQcRBEpCMDRuS8I/XbmXzzaNXcOuq33oAusK8P12ABTfgvbKs/QrdY6JvZY= 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: On Wed, 4 Oct 2023 20:18:12 -0700 (PDT) David Rientjes wrote: > On Wed, 27 Sep 2023, Jiaqi Yan wrote: > > > > > 1. I am not aware of any chip/platform hardware that implemented the > > > > hw ps part defined in ACPI RASF/RAS2 spec. So I am curious what the > > > > RAS experts from different hardware vendors think about this. For > > > > example, Tony and Dave from Intel, Jon and Vilas from AMD. Is there > > > > any hardware platform (if allowed to disclose) that implemented ACPI > > > > RASF/RAS2? If so, will vendors continue to support the control of > > > > patrol scrubber using the ACPI spec? If not (as Tony said in [1], will > > > > the vendor consider starting some future platform? > > > > > > > > If we are unlikely to get the vendor support, creating this ACPI > > > > specific sysfs API (and the driver implementations) in Linux seems to > > > > have limited meaning. > > > > > > There is a bit of a chicken and egg problem here. Until there is > > > reasonable support in kernel (or it looks like there will be), > > > BIOS teams push back on a requirement to add the tables. > > > I'd encourage no one to bother with RASF - RAS2 is much less > > > ambiguous. > > > > Here mainly to re-ping folks from Intel (Tony and Dave) and AMD (Jon > > and Vilas) for your opinion on RAS2. > > > > We'll need to know from vendors, ideally at minimum from both Intel and > AMD, whether RAS2 is the long-term vision here. Nothing is set in stone, > of course, but deciding whether RAS2 is the standard that we should be > rallying around will help to guide future development including in the > kernel. > > If RAS2 is insufficient for future use cases or we would need to support > multiple implementations in the kernel for configuring the patrol scrubber > depending on vendor, that's great feedback to have. > > I'd much rather focus on implementing something in the kernel that we have > some clarity about the vendors supporting, especially when it comes with > user visible interfaces, as opposed to something that may not be used long > term. I think that's a fair ask and that vendor feedback is required > here? Agreed and happy to have feedback from Intel and AMD + all the other CPU vendors who make use of ACPI + all the OEMs who add stuff well beyond what Intel and AMD tell them to :) I'll just note a lot of the ACPI support in the kernel covers stuff not used on mainstream x86 platforms because they are doing something custom and we didn't want 2 + X custom implementations... Some other interfaces for scrub control (beyond existing embedded ones) will surface in the next few months where RAS2 is not appropriate. Jonathan