From nobody Tue Feb 10 11:32:56 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) client-ip=192.237.175.120; envelope-from=xen-devel-bounces@lists.xenproject.org; helo=lists.xenproject.org; Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org ARC-Seal: i=1; a=rsa-sha256; t=1687194120; cv=none; d=zohomail.com; s=zohoarc; b=fIEWKtdEIIA5cNq/wZ2tfACGlUxha2dC7ng79jDU1MSbLHOixtTnY64qCGfnQA088mpfzXJZ7FwhjuRgLhXzcBQbrZKuyNMEL24uS/bNCl4BJ1l91xlYtG3cTzieiK4rYgb99cnf5Gcp0JDHpKCAwWR/JROsA4HaHjaN5c1nVlk= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1687194120; h=Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To; bh=f0Msc+xsVYLFDQx2YMgcMthu7/P+yNsRuDofE8DHCTI=; b=U7FBI6ZO+k7e9VqlkW3BdtY98NUaFzxLhVqoqpybXLpelQB6aQdzENy5OHUeUqePAGmPy0UzilK3JYmvL+ekpH//dkpJqp7ACSV1tfH0z/tvDhtNGYCTanNdnelOCO/6AzUZvJXtZZYXVJdo2yWxdg/+pUUk57obr+SI713WNOk= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Return-Path: Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) by mx.zohomail.com with SMTPS id 1687194120328809.8088106275464; Mon, 19 Jun 2023 10:02:00 -0700 (PDT) Received: from list by lists.xenproject.org with outflank-mailman.551242.860680 (Exim 4.92) (envelope-from ) id 1qBIFm-0003PW-GU; Mon, 19 Jun 2023 17:01:22 +0000 Received: by outflank-mailman (output) from mailman id 551242.860680; Mon, 19 Jun 2023 17:01:22 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1qBIFm-0003PP-CK; Mon, 19 Jun 2023 17:01:22 +0000 Received: by outflank-mailman (input) for mailman id 551242; Mon, 19 Jun 2023 17:01:20 +0000 Received: from mail.xenproject.org ([104.130.215.37]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1qBIFk-0003Kd-Ox for xen-devel@lists.xenproject.org; Mon, 19 Jun 2023 17:01:20 +0000 Received: from xenbits.xenproject.org ([104.239.192.120]) by mail.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1qBIFk-0002e2-Am; Mon, 19 Jun 2023 17:01:20 +0000 Received: from 54-240-197-232.amazon.com ([54.240.197.232] helo=dev-dsk-jgrall-1b-035652ec.eu-west-1.amazon.com) by xenbits.xenproject.org with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.92) (envelope-from ) id 1qBIFk-00079R-1n; Mon, 19 Jun 2023 17:01:20 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=xen.org; s=20200302mail; h=Content-Transfer-Encoding:MIME-Version:References: In-Reply-To:Message-Id:Date:Subject:Cc:To:From; bh=f0Msc+xsVYLFDQx2YMgcMthu7/P+yNsRuDofE8DHCTI=; b=2hI+1r6bez1izKN5mYzfSlrs/9 m1HXM0JjawBY4PuhMeUvfOEFjgIIFJuYB1O57140gBQ0NU3z58+ibu68aAopE3zL7Jx2Uid1hxPBw h9N824YNpqhoNfnbNMN3dKj29TSlSGl0PxoJKS6dg0rIBgtM00UPuDwdtvxcW1VpFalk=; From: Julien Grall To: xen-devel@lists.xenproject.org Cc: Luca.Fancellu@arm.com, michal.orzel@amd.com, Henry.Wang@arm.com, Julien Grall , Stefano Stabellini , Julien Grall , Bertrand Marquis , Volodymyr Babchuk Subject: [PATCH 1/7] xen/arm32: head: Add missing isb in setup_fixmap() Date: Mon, 19 Jun 2023 18:01:09 +0100 Message-Id: <20230619170115.81398-2-julien@xen.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230619170115.81398-1-julien@xen.org> References: <20230619170115.81398-1-julien@xen.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ZohoMail-DKIM: pass (identity @xen.org) X-ZM-MESSAGEID: 1687194122196100009 Content-Type: text/plain; charset="utf-8" From: Julien Grall Per the Arm Arm (ARM DDI 0406C.d A3.8.3): "The DMB and DSB memory barriers affect reads and writes to the memory system generated by load/store instructions and data or unified cache maintenance operations being executed by the processor. Instruction fetches or accesses caused by a hardware translation table access are not explicit accesses." In setup_fixmap(), we write the fixmap area and may be used soon after, for instance, to write to the UART. IOW, there could be hardware translation table access. So we need to ensure the 'dsb' has completed before continuing. Therefore add an 'isb'. Fixes: e79999e587d7 ("xen/arm32: head: Remove 1:1 mapping as soon as it is = not used") Signed-off-by: Julien Grall Reviewed-by: Bertrand Marquis Reviewed-by: Henry Wang Reviewed-by: Luca Fancellu Tested-by: Henry Wang --- xen/arch/arm/arm32/head.S | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/xen/arch/arm/arm32/head.S b/xen/arch/arm/arm32/head.S index f9f7be9588b1..6ca3329138e3 100644 --- a/xen/arch/arm/arm32/head.S +++ b/xen/arch/arm/arm32/head.S @@ -751,6 +751,11 @@ setup_fixmap: create_table_entry boot_second, xen_fixmap, r0, 2 /* Ensure any page table updates made above have occurred. */ dsb nshst + /* + * The fixmap area will be used soon after. So ensure no hardware + * translation happens before the dsb completes. + */ + isb =20 mov pc, lr ENDPROC(setup_fixmap) --=20 2.40.1