From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755229AbcEYGbp (ORCPT ); Wed, 25 May 2016 02:31:45 -0400 Received: from mx1.redhat.com ([209.132.183.28]:54744 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753374AbcEYG3G (ORCPT ); Wed, 25 May 2016 02:29:06 -0400 From: Baoquan He To: joro@8bytes.org Cc: iommu@lists.linux-foundation.org, vincent.wan@amd.com, xlpang@redhat.com, dyoung@redhat.com, linux-kernel@vger.kernel.org, Baoquan He Subject: [Patch v4 1/9] iommu/amd: clean up the cmpxchg64 invocation Date: Wed, 25 May 2016 14:28:47 +0800 Message-Id: <1464157735-8865-2-git-send-email-bhe@redhat.com> In-Reply-To: <1464157735-8865-1-git-send-email-bhe@redhat.com> References: <1464157735-8865-1-git-send-email-bhe@redhat.com> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Wed, 25 May 2016 06:29:05 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Change it as it's designed for and keep it consistent with other places. Signed-off-by: Baoquan He --- drivers/iommu/amd_iommu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index 5efadad..9ec7cad 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -1287,7 +1287,8 @@ static u64 *alloc_pte(struct protection_domain *domain, __npte = PM_LEVEL_PDE(level, virt_to_phys(page)); - if (cmpxchg64(pte, __pte, __npte)) { + /* pte could have been changed somewhere. */ + if (cmpxchg64(pte, __pte, __npte) != __pte) { free_page((unsigned long)page); continue; } -- 2.5.5