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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AB930C433EF for ; Tue, 28 Sep 2021 18:51:59 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 4052C6124A for ; Tue, 28 Sep 2021 18:51:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 4052C6124A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=quicinc.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id B654C6B0071; Tue, 28 Sep 2021 14:51:58 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B147C900002; Tue, 28 Sep 2021 14:51:58 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A50C76B0073; Tue, 28 Sep 2021 14:51:58 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0214.hostedemail.com [216.40.44.214]) by kanga.kvack.org (Postfix) with ESMTP id 99A2E6B0071 for ; Tue, 28 Sep 2021 14:51:58 -0400 (EDT) Received: from smtpin16.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 575CA182D5C97 for ; Tue, 28 Sep 2021 18:51:58 +0000 (UTC) X-FDA: 78637876716.16.C77B1FC Received: from alexa-out.qualcomm.com (alexa-out.qualcomm.com [129.46.98.28]) by imf04.hostedemail.com (Postfix) with ESMTP id C40AE50000B6 for ; Tue, 28 Sep 2021 18:51:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; i=@quicinc.com; q=dns/txt; s=qcdkim; t=1632855118; x=1664391118; h=from:to:cc:subject:date:message-id:mime-version; bh=i7LKpC2fde133igJaoJ2gVd1E/F2FN0XTx3T9Dr3+Dw=; b=M+OzSa/tRxwVhtWdkIAcXD4+GAJPb5ks1vVhTBKBQR/XA/YHY3fjTGsP LgS0NwSZYfJGqlto42YYSgOH3vADef6zXauSKpN/qatzKHu2+6vTetsxs 7QF5BIslMxdQBaN9zV+TukbvBWsxahfF/B+YSDbTlKoK5ALXtDUX916jW 8=; Received: from ironmsg07-lv.qualcomm.com ([10.47.202.151]) by alexa-out.qualcomm.com with ESMTP; 28 Sep 2021 11:51:57 -0700 X-QCInternal: smtphost Received: from nalasex01a.na.qualcomm.com ([10.47.209.196]) by ironmsg07-lv.qualcomm.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Sep 2021 11:51:56 -0700 Received: from hu-cgoldswo-sd.qualcomm.com (10.80.80.8) by nalasex01a.na.qualcomm.com (10.47.209.196) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.922.7; Tue, 28 Sep 2021 11:51:55 -0700 From: Chris Goldsworthy To: Andrew Morton CC: David Hildenbrand , Catalin Marinas , Will Deacon , "Sudarshan Rajagopalan" , Georgi Djakov , , , , Chris Goldsworthy Subject: arm64: mm: update max_pfn after memory hotplug Date: Tue, 28 Sep 2021 11:51:48 -0700 Message-ID: X-Mailer: git-send-email 2.7.4 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01b.na.qualcomm.com (10.46.141.250) To nalasex01a.na.qualcomm.com (10.47.209.196) Authentication-Results: imf04.hostedemail.com; dkim=pass header.d=quicinc.com header.s=qcdkim header.b="M+OzSa/t"; spf=pass (imf04.hostedemail.com: domain of quic_cgoldswo@quicinc.com designates 129.46.98.28 as permitted sender) smtp.mailfrom=quic_cgoldswo@quicinc.com; dmarc=pass (policy=none) header.from=quicinc.com X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: C40AE50000B6 X-Stat-Signature: w649pjr3s8muoqncx6ti5orznsjrists X-HE-Tag: 1632855117-652664 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: Follow up of RFC patch: https://lore.kernel.org/linux-mm/a3bf84c4-8f35-f273-145c-55928a06f332@quicinc.com/T/#m219937b1acdd40318bbe90ab39f187804775eb74 On arm64 we set max_pfn at boot in arch/arm64/mm/init.c. If you hotplug in memory after booting up, max_pfn is not updated. This breaks diagnostic functions executed from user space like read_page_owner(): https://elixir.bootlin.com/linux/v5.14.7/source/mm/page_owner.c#L472 or kpageflags_read() (see how get_max_dump_pfn() is used): https://elixir.bootlin.com/linux/v5.14.7/source/fs/proc/page.c#L47 Thus, this patch updates max_pfn and max_low_pfn in arm64's arch_add_memory() function, mirroring what is updatated during boot: https://elixir.bootlin.com/linux/v5.14.7/source/arch/arm64/mm/init.c#L448 Quick reference for David's Acked-by, with a follow-up discussion on max_low_pfn: https://lore.kernel.org/linux-mm/a3bf84c4-8f35-f273-145c-55928a06f332@quicinc.com/T/#m7d30b3afa632a4fa836f5fe55f4ee8e7bbc83e5d https://lore.kernel.org/linux-mm/a3bf84c4-8f35-f273-145c-55928a06f332@quicinc.com/T/#m0d0e509375af1504d25451d079c5cbd6e7aa513b Sudarshan Rajagopalan (1): arm64: mm: update max_pfn after memory hotplug arch/arm64/mm/mmu.c | 5 +++++ 1 file changed, 5 insertions(+) -- 2.7.4