From patchwork Wed Aug 23 13:13:40 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexandru Elisei X-Patchwork-Id: 13362356 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 49281EE49A0 for ; Wed, 23 Aug 2023 13:17:48 +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=96YiYH3u1Q+rbkDQUCINrket+lUwxFxspsjMPTHoZP4=; b=2TVhaq5gzEaTZ2 UXUp1Ykhyn+GHI6YjCLWGKpKtSGJGQtgQeIa3AhAZS5hK5k06x1sM4CXDQQyTR03PouEPwWRIqwEz E7Yws6sURGpg6LZn2orWLMPfzyrDmmFlBlwJLJgl4ivLicQ6Ic+Ya+N6+4PCo+R4FWeOVUkZXvhmT Knw/c33oSSnraejLAOTVx/IC5/0Reu6QnhxkK+JU0hSTKmsptrB0ihqCFyi2til48OkBfvyqGOJbX cySFfZMyx33LkjZ3e98pOQekzG9lt9dtDxKppPfrCVbOzT1ZgGegCK6DDw2JWaVkawiVcDtytNVNs lD/s8tUnVfzuetfnQqFQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qYnjb-000e42-2s; Wed, 23 Aug 2023 13:17:19 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qYnjN-000dst-1U for linux-arm-kernel@lists.infradead.org; Wed, 23 Aug 2023 13:17:07 +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 1A4C816F2; Wed, 23 Aug 2023 06:17:45 -0700 (PDT) Received: from e121798.cable.virginm.net (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 9BF043F740; Wed, 23 Aug 2023 06:16:58 -0700 (PDT) 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 27/37] arm64: mte: Reserve tag block for the zero page Date: Wed, 23 Aug 2023 14:13:40 +0100 Message-Id: <20230823131350.114942-28-alexandru.elisei@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230823131350.114942-1-alexandru.elisei@arm.com> References: <20230823131350.114942-1-alexandru.elisei@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230823_061705_545889_CF2D5927 X-CRM114-Status: GOOD ( 10.14 ) 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 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 7dff93492a7b..1ab875be5f9b 100644 --- a/arch/arm64/kernel/mte_tag_storage.c +++ b/arch/arm64/kernel/mte_tag_storage.c @@ -398,6 +398,8 @@ static int __init mte_tag_storage_activate_regions(void) } } + ret = reserve_metadata_storage(ZERO_PAGE(0), 0, GFP_HIGHUSER_MOVABLE); + return ret; } core_initcall(mte_tag_storage_activate_regions);