From patchwork Thu Sep 26 09:45:31 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Xia, Hongyan" X-Patchwork-Id: 11162055 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 D16A613B1 for ; Thu, 26 Sep 2019 09:48:58 +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 AD269222C0 for ; Thu, 26 Sep 2019 09:48:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=amazon.com header.i=@amazon.com header.b="o8YFuwEZ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AD269222C0 Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=amazon.com Authentication-Results: mail.kernel.org; spf=none 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 1iDQNC-0003jt-CK; Thu, 26 Sep 2019 09:47:42 +0000 Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1iDQNA-0003jH-Ld for xen-devel@lists.xenproject.org; Thu, 26 Sep 2019 09:47:40 +0000 X-Inumbo-ID: addfbb1d-e042-11e9-964c-12813bfff9fa Received: from smtp-fw-6002.amazon.com (unknown [52.95.49.90]) by localhost (Halon) with ESMTPS id addfbb1d-e042-11e9-964c-12813bfff9fa; Thu, 26 Sep 2019 09:47:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1569491260; x=1601027260; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version; bh=Mauyqd924PdT/m+H441U/gI5RxdAY067bvDgJxjGF/A=; b=o8YFuwEZOU0dKjpazJlMlMas92ZT8eD3/Ce4d4Cj4ZRzkwye9u9O3zWu QYdmqn6Pos5tuwjp5PbM7y+rQOVZ3aAZ3YygF5c23Xrq2yJWJ4PgFABSB 9sa6l9myW0VSzRhRx/Hd9yyoroHsKKeNjEKYhz5ryM5CPldYo43nzKEyu E=; X-IronPort-AV: E=Sophos;i="5.64,551,1559520000"; d="scan'208";a="423750365" Received: from iad6-co-svc-p1-lb1-vlan3.amazon.com (HELO email-inbound-relay-1a-807d4a99.us-east-1.amazon.com) ([10.124.125.6]) by smtp-border-fw-out-6002.iad6.amazon.com with ESMTP; 26 Sep 2019 09:47:39 +0000 Received: from EX13MTAUWA001.ant.amazon.com (iad55-ws-svc-p15-lb9-vlan2.iad.amazon.com [10.40.159.162]) by email-inbound-relay-1a-807d4a99.us-east-1.amazon.com (Postfix) with ESMTPS id E3DECA1F34; Thu, 26 Sep 2019 09:47:37 +0000 (UTC) Received: from EX13P01UWA003.ant.amazon.com (10.43.160.197) by EX13MTAUWA001.ant.amazon.com (10.43.160.58) with Microsoft SMTP Server (TLS) id 15.0.1367.3; Thu, 26 Sep 2019 09:47:08 +0000 Received: from EX13MTAUWA001.ant.amazon.com (10.43.160.58) by EX13P01UWA003.ant.amazon.com (10.43.160.197) with Microsoft SMTP Server (TLS) id 15.0.1367.3; Thu, 26 Sep 2019 09:47:08 +0000 Received: from u9d785c4ba99158.ant.amazon.com (10.125.106.58) by mail-relay.amazon.com (10.43.160.118) with Microsoft SMTP Server id 15.0.1367.3 via Frontend Transport; Thu, 26 Sep 2019 09:47:07 +0000 From: To: Date: Thu, 26 Sep 2019 10:45:31 +0100 Message-ID: X-Mailer: git-send-email 2.17.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: Bulk Subject: [Xen-devel] [RFC PATCH 08/84] x86/mm: make sure there is one exit path for modify_xen_mappings X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.23 List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Andrew Cooper , Wei Liu , Wei Liu , Jan Beulich , =?utf-8?q?Roger_Pau_?= =?utf-8?q?Monn=C3=A9?= Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" From: Wei Liu We will soon need to handle dynamically mapping / unmapping page tables in the said function. No functional change. Signed-off-by: Wei Liu --- xen/arch/x86/mm.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/xen/arch/x86/mm.c b/xen/arch/x86/mm.c index 0916aa74ae..3a799e17e4 100644 --- a/xen/arch/x86/mm.c +++ b/xen/arch/x86/mm.c @@ -5425,6 +5425,7 @@ int modify_xen_mappings(unsigned long s, unsigned long e, unsigned int nf) l1_pgentry_t *pl1e; unsigned int i; unsigned long v = s; + int rc = -ENOMEM; /* Set of valid PTE bits which may be altered. */ #define FLAGS_MASK (_PAGE_NX|_PAGE_RW|_PAGE_PRESENT) @@ -5468,7 +5469,11 @@ int modify_xen_mappings(unsigned long s, unsigned long e, unsigned int nf) /* PAGE1GB: shatter the superpage and fall through. */ l2t = alloc_xen_pagetable(); if ( !l2t ) - return -ENOMEM; + { + ASSERT(rc == -ENOMEM); + goto out; + } + for ( i = 0; i < L2_PAGETABLE_ENTRIES; i++ ) l2e_write(l2t + i, l2e_from_pfn(l3e_get_pfn(*pl3e) + @@ -5525,7 +5530,11 @@ int modify_xen_mappings(unsigned long s, unsigned long e, unsigned int nf) /* PSE: shatter the superpage and try again. */ l1t = alloc_xen_pagetable(); if ( !l1t ) - return -ENOMEM; + { + ASSERT(rc == -ENOMEM); + goto out; + } + for ( i = 0; i < L1_PAGETABLE_ENTRIES; i++ ) l1e_write(&l1t[i], l1e_from_pfn(l2e_get_pfn(*pl2e) + i, @@ -5658,7 +5667,10 @@ int modify_xen_mappings(unsigned long s, unsigned long e, unsigned int nf) flush_area(NULL, FLUSH_TLB_GLOBAL); #undef FLAGS_MASK - return 0; + rc = 0; + + out: + return rc; } #undef flush_area