Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S972973AbdDXQIw (ORCPT ); Mon, 24 Apr 2017 12:08:52 -0400 Received: from foss.arm.com ([217.140.101.70]:58780 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S972969AbdDXQIm (ORCPT ); Mon, 24 Apr 2017 12:08:42 -0400 Date: Mon, 24 Apr 2017 17:08:41 +0100 From: Will Deacon To: Geetha sowjanya Cc: robin.murphy@arm.com, iommu@lists.linux-foundation.org, catalin.marinas@arm.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Sunil.Goutham@cavium.com, Geetha Subject: Re: [PATCH] iommu/arm-smmu-v3: Increase SMMU CMD queue poll timeout Message-ID: <20170424160841.GS12323@arm.com> References: <1493035176-3633-1-git-send-email-gakula@caviumnetworks.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1493035176-3633-1-git-send-email-gakula@caviumnetworks.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1230 Lines: 38 On Mon, Apr 24, 2017 at 05:29:36PM +0530, Geetha sowjanya wrote: > From: Geetha > > When large memory is being unmapped, huge no of tlb invalidation cmds are > submitted followed by a SYNC command. This sometimes hits CMD queue full and > poll on queue drain is being timedout throwing error message 'CMD_SYNC timeout'. > > Although there is no functional issue, error message confuses user. Hence increased > poll timeout to 500us Hmm, what are you doing to unmap that much? Is this VFIO teardown? Do you have 7c6d90e2bb1a ("iommu/io-pgtable-arm: Fix iova_to_phys for block entries") applied? Will > > Signed-off-by: Geetha > --- > drivers/iommu/arm-smmu-v3.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c > index 591bb96..1dcd154 100644 > --- a/drivers/iommu/arm-smmu-v3.c > +++ b/drivers/iommu/arm-smmu-v3.c > @@ -407,7 +407,7 @@ > #define PRIQ_1_ADDR_MASK 0xfffffffffffffUL > > /* High-level queue structures */ > -#define ARM_SMMU_POLL_TIMEOUT_US 100 > +#define ARM_SMMU_POLL_TIMEOUT_US 500 > > #define MSI_IOVA_BASE 0x8000000 > #define MSI_IOVA_LENGTH 0x100000 > -- > 1.9.1 >