From patchwork Thu Apr 16 15:46:50 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Beulich X-Patchwork-Id: 11493283 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id EE6B01392 for ; Thu, 16 Apr 2020 15:47:55 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D14B420732 for ; Thu, 16 Apr 2020 15:47:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D14B420732 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1jP6j9-0006E3-DH; Thu, 16 Apr 2020 15:46:55 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1jP6j7-0006Dk-L7 for xen-devel@lists.xenproject.org; Thu, 16 Apr 2020 15:46:53 +0000 X-Inumbo-ID: 7e1ba772-7ff9-11ea-b58d-bc764e2007e4 Received: from mx2.suse.de (unknown [195.135.220.15]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id 7e1ba772-7ff9-11ea-b58d-bc764e2007e4; Thu, 16 Apr 2020 15:46:53 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 82129AC79; Thu, 16 Apr 2020 15:46:51 +0000 (UTC) Subject: [PATCH 4/6] x86/mem-paging: add minimal lock order enforcement to p2m_mem_paging_prep() From: Jan Beulich To: "xen-devel@lists.xenproject.org" References: <3b7cc69d-709c-570a-716a-c45f6fda181f@suse.com> Message-ID: Date: Thu, 16 Apr 2020 17:46:50 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: <3b7cc69d-709c-570a-716a-c45f6fda181f@suse.com> Content-Language: en-US X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Andrew Cooper , George Dunlap , Wei Liu , =?utf-8?q?R?= =?utf-8?q?oger_Pau_Monn=C3=A9?= Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" While full checking is impossible (as the lock is being acquired/ released down the call tree), perform at least a lock level check. Signed-off-by: Jan Beulich --- a/xen/arch/x86/mm/p2m.c +++ b/xen/arch/x86/mm/p2m.c @@ -1813,6 +1813,7 @@ int p2m_mem_paging_prep(struct domain *d goto out; /* Get a free page */ ret = -ENOMEM; + page_alloc_mm_pre_lock(d); page = alloc_domheap_page(d, 0); if ( unlikely(page == NULL) ) goto out;