Return-Path: linux-nfs-owner@vger.kernel.org Received: from cantor2.suse.de ([195.135.220.15]:57991 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754194Ab2JDKy6 (ORCPT ); Thu, 4 Oct 2012 06:54:58 -0400 Subject: Re: [PATCH] powerpc/iommu: Fix multiple issues with IOMMU pools code Mime-Version: 1.0 (Apple Message framework v1278) Content-Type: text/plain; charset=us-ascii From: Alexander Graf In-Reply-To: <20121004145710.2cf95dcd@kryten> Date: Thu, 4 Oct 2012 12:54:45 +0200 Cc: Nishanth Aravamudan , Benjamin Herrenschmidt , linux-nfs@vger.kernel.org, Jan Kara , Linus Torvalds , LKML List , "J. Bruce Fields" , skinsbursky@parallels.com, bfields@redhat.com, linuxppc-dev Message-Id: <96119AB6-3DCC-460E-BD40-98DC3BB8D4B4@suse.de> References: <3BDA9E62-7031-42D6-8CA9-5327B61700F5@suse.de> <20120928151043.GA19102@fieldses.org> <2A52FC96-148C-4F7A-9950-E152E0C6698D@suse.de> <1349139509.3847.2.camel@pasglop> <20121002214327.GA29218@linux.vnet.ibm.com> <9257E705-4EF9-4347-945C-B4A7582C427F@suse.de> <20121002221736.GB29218@linux.vnet.ibm.com> <20121004145710.2cf95dcd@kryten> To: Anton Blanchard Sender: linux-nfs-owner@vger.kernel.org List-ID: Hi Anton, On 04.10.2012, at 06:57, Anton Blanchard wrote: > > Hi Alex, > > Looks to be a preempt issue with the iommu pools code. I did find a > couple more bugs along the way too. > > Anton > -- > > There are a number of issues in the recent IOMMU pools code: > > - On a preempt kernel we might switch CPUs in the middle of building > a scatter gather list. When this happens the handle hint passed in > no longer falls within the local CPU's pool. Check for this and > fall back to the pool hint. > > - We were missing a spin_unlock/spin_lock in one spot where we > switch pools. > > - We need to provide locking around dart_tlb_invalidate_all and > dart_tlb_invalidate_one now that the global lock is gone. > > Reported-by: Alexander Graf > Signed-off-by: Anton Blanchard > --- > > There is still an issue with the lazy u3 flushing, but I wanted > to get this out for testing. Yup. It fixes the nfs problem on my U4 based machine. Tested-by: Alexander Graf Alex