From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 95517C433F5 for ; Wed, 13 Apr 2022 13:40:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235900AbiDMNnF (ORCPT ); Wed, 13 Apr 2022 09:43:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51620 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235876AbiDMNm7 (ORCPT ); Wed, 13 Apr 2022 09:42:59 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 3042B5EDFD for ; Wed, 13 Apr 2022 06:40:38 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id EAB2C1596; Wed, 13 Apr 2022 06:40:37 -0700 (PDT) Received: from [10.57.41.19] (unknown [10.57.41.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 15A933F73B; Wed, 13 Apr 2022 06:40:35 -0700 (PDT) Message-ID: <37c02fc4-d793-b003-f612-206c987a8a42@arm.com> Date: Wed, 13 Apr 2022 14:40:31 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; rv:91.0) Gecko/20100101 Thunderbird/91.8.0 Subject: Re: [PATCH] iommu/arm-smmu-v3: Align size in __arm_smmu_tlb_inv_range Content-Language: en-GB To: Nicolin Chen , will@kernel.org, joro@8bytes.org Cc: thunder.leizhen@huawei.com, jgg@ziepe.ca, tglx@linutronix.de, john.garry@huawei.com, jean-philippe@linaro.org, christophe.jaillet@wanadoo.fr, linux-arm-kernel@lists.infradead.org, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org References: <20220413041745.35174-1-nicolinc@nvidia.com> From: Robin Murphy In-Reply-To: <20220413041745.35174-1-nicolinc@nvidia.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2022-04-13 05:17, Nicolin Chen wrote: > To calculate num_pages, the size should be aligned with > "page size", determined by the tg value. Otherwise, its > following "while (iova < end)" might become an infinite > loop if unaligned size is slightly greater than 1 << tg. Hmm, how does a non-page-aligned invalidation request get generated in the first place? Robin. > Signed-off-by: Nicolin Chen > --- > drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > index 627a3ed5ee8f..8249dad5ae44 100644 > --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > @@ -1879,7 +1879,7 @@ static void __arm_smmu_tlb_inv_range(struct arm_smmu_cmdq_ent *cmd, > /* Determine what level the granule is at */ > cmd->tlbi.ttl = 4 - ((ilog2(granule) - 3) / (tg - 3)); > > - num_pages = size >> tg; > + num_pages = ALIGN(size, 1 << tg) >> tg; > } > > cmds.num = 0;