From patchwork Mon Sep 3 12:43:52 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Petazzoni X-Patchwork-Id: 1399711 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) by patchwork2.kernel.org (Postfix) with ESMTP id B3B3CDF280 for ; Mon, 3 Sep 2012 12:46:59 +0000 (UTC) Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1T8W0m-0005Ff-RO; Mon, 03 Sep 2012 12:44:16 +0000 Received: from mail.free-electrons.com ([88.190.12.23]) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1T8W0i-0005ED-Tb for linux-arm-kernel@lists.infradead.org; Mon, 03 Sep 2012 12:44:13 +0000 Received: by mail.free-electrons.com (Postfix, from userid 106) id 8BDD9188; Mon, 3 Sep 2012 14:44:11 +0200 (CEST) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.free-electrons.com X-Spam-Level: X-Spam-Status: No, score=-2.9 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00, KHOP_BIG_TO_CC shortcircuit=no autolearn=ham version=3.3.1 Received: from localhost (col31-4-88-188-83-94.fbx.proxad.net [88.188.83.94]) by mail.free-electrons.com (Postfix) with ESMTPSA id 9E159155; Mon, 3 Sep 2012 14:44:03 +0200 (CEST) From: Thomas Petazzoni To: linux-arm-kernel@lists.infradead.org Subject: [PATCH] arm: mm: fix DMA pool affiliation check Date: Mon, 3 Sep 2012 14:43:52 +0200 Message-Id: <1346676232-3566-1-git-send-email-thomas.petazzoni@free-electrons.com> X-Mailer: git-send-email 1.7.9.5 X-Spam-Note: CRM114 invocation failed X-Spam-Score: -2.1 (--) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-2.1 points) pts rule name description ---- ---------------------- -------------------------------------------------- 0.0 KHOP_BIG_TO_CC Sent to 10+ recipients instaed of Bcc or a list -0.0 SPF_PASS SPF: sender matches SPF record -0.2 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Cc: Lior Amsalem , Yehuda Yitschak , Russell King , Tawfik Bayouk , Eran Ben-Avi , Nadav Haklai , Maen Suleiman , Shadi Ammouri , Gregory Clement , Marek Szyprowski X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org The __free_from_pool() function was changed in e9da6e9905e639b0f842a244bc770b48ad0523e9. Unfortunately, the test that checks whether the provided (start,size) is within the DMA pool has been improperly modified. It used to be: if (start < coherent_head.vm_start || end > coherent_head.vm_end) Where coherent_head.vm_end was non-inclusive (i.e, it did not include the first byte after the pool). The test has been changed to: if (start < pool->vaddr || start > pool->vaddr + pool->size) So now pool->vaddr + pool->size is inclusive (i.e, it includes the first byte after the pool), so the test should be >= instead of >. This bug causes the following message when freeing the *first* DMA coherent buffer that has been allocated, because its virtual address is exactly equal to pool->vaddr + pool->size : WARNING: at /home/thomas/projets/linux-2.6/arch/arm/mm/dma-mapping.c:463 __free_from_pool+0xa4/0xc0() freeing wrong coherent size from pool Signed-off-by: Thomas Petazzoni Cc: Marek Szyprowski Cc: Russell King Cc: Lior Amsalem Cc: Maen Suleiman Cc: Tawfik Bayouk Cc: Shadi Ammouri Cc: Eran Ben-Avi Cc: Yehuda Yitschak Cc: Nadav Haklai --- arch/arm/mm/dma-mapping.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 4e7d118..59d9062 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -456,7 +456,7 @@ static int __free_from_pool(void *start, size_t size) unsigned long pageno, count; unsigned long flags; - if (start < pool->vaddr || start > pool->vaddr + pool->size) + if (start < pool->vaddr || start >= pool->vaddr + pool->size) return 0; if (start + size > pool->vaddr + pool->size) {