From patchwork Sun Nov 19 16:57:12 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexandru Elisei X-Patchwork-Id: 13460604 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A2096C072A2 for ; Sun, 19 Nov 2023 16:59:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=7YHpZvZG47Ol11mnMyxFPgxfiN1p4dLZBIM0MNyj2xY=; b=W9OCP5Jcwp9zA3 yS69ji8CD0udfkyYmrHBiruIVV9aKzdbTMEVoClnBlgSECI6igJ65ubeBNHaGKSNfrfaPvhoYMZby qsZRueLDIypfMml3Ak3pjEnGOQJYBADTjYMvpLO5gFo1bsuxeVFVIUry+XjNgHPhr3VNXT3stXZ7u 2BDOp3wP0B/yDDWp5osaLjZM8wzWBwSeSuUyt6MpfYbtkE9DWLxGk6UDhOFamCNYUh70uzXAOpyp1 apVpG+2bvrV+wcTlipcgKVTdZMcFU3n48q6zw6BGqx1vXCMcmgSLAj9kSyrRM24NcmB8mdcZSXgeN VQzUELPaRUB1kpyJbabw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1r4l8m-00ARYc-2P; Sun, 19 Nov 2023 16:59:25 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1r4l8c-00ARPq-2t for linux-arm-kernel@lists.infradead.org; Sun, 19 Nov 2023 16:59:16 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 90D471007; Sun, 19 Nov 2023 09:00:00 -0800 (PST) Received: from e121798.cable.virginm.net (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 64C553F6C4; Sun, 19 Nov 2023 08:59:09 -0800 (PST) From: Alexandru Elisei To: catalin.marinas@arm.com, will@kernel.org, oliver.upton@linux.dev, maz@kernel.org, james.morse@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, arnd@arndb.de, akpm@linux-foundation.org, mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com, mhiramat@kernel.org, rppt@kernel.org, hughd@google.com Cc: pcc@google.com, steven.price@arm.com, anshuman.khandual@arm.com, vincenzo.frascino@arm.com, david@redhat.com, eugenis@google.com, kcc@google.com, hyesoo.yu@samsung.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kvmarm@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-trace-kernel@vger.kernel.org Subject: [PATCH RFC v2 18/27] arm64: mte: Reserve tag block for the zero page Date: Sun, 19 Nov 2023 16:57:12 +0000 Message-Id: <20231119165721.9849-19-alexandru.elisei@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231119165721.9849-1-alexandru.elisei@arm.com> References: <20231119165721.9849-1-alexandru.elisei@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231119_085914_977334_C618DE32 X-CRM114-Status: UNSURE ( 9.69 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On arm64, the zero page receives special treatment by having the tagged flag set on MTE initialization, not when the page is mapped in a process address space. Reserve the corresponding tag block when tag storage management is being activated. Signed-off-by: Alexandru Elisei --- arch/arm64/kernel/mte_tag_storage.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/arm64/kernel/mte_tag_storage.c b/arch/arm64/kernel/mte_tag_storage.c index 833480048170..a1cc239f7211 100644 --- a/arch/arm64/kernel/mte_tag_storage.c +++ b/arch/arm64/kernel/mte_tag_storage.c @@ -393,6 +393,8 @@ static int __init mte_tag_storage_activate_regions(void) totalcma_pages += range_len(tag_range); } + reserve_tag_storage(ZERO_PAGE(0), 0, GFP_HIGHUSER_MOVABLE); + return 0; out_disabled: