From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45656) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YxFPG-0005UJ-Df for qemu-devel@nongnu.org; Tue, 26 May 2015 10:00:39 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YxFPA-0007Ue-IB for qemu-devel@nongnu.org; Tue, 26 May 2015 10:00:34 -0400 Received: from mail-pd0-f182.google.com ([209.85.192.182]:35823) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YxFPA-0007UU-Cl for qemu-devel@nongnu.org; Tue, 26 May 2015 10:00:28 -0400 Received: by pdea3 with SMTP id a3so91519050pde.2 for ; Tue, 26 May 2015 07:00:27 -0700 (PDT) Message-ID: <55647C75.5000704@ozlabs.ru> Date: Wed, 27 May 2015 00:00:21 +1000 From: Alexey Kardashevskiy MIME-Version: 1.0 References: <1429964684-23872-1-git-send-email-aik@ozlabs.ru> <1429964684-23872-7-git-send-email-aik@ozlabs.ru> <55633A54.8080807@ozlabs.ru> <20150526024628.GA30620@voom.redhat.com> <5564359A.2070009@redhat.com> <556447BB.9000802@ozlabs.ru> <55644819.3000003@redhat.com> <55646803.8040007@ozlabs.ru> <55646C18.4000303@redhat.com> <5564750C.8000100@ozlabs.ru> <556475BD.50401@redhat.com> <55647843.4040609@ozlabs.ru> <556479B6.1010501@redhat.com> In-Reply-To: <556479B6.1010501@redhat.com> Content-Type: text/plain; charset=koi8-r; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH qemu v7 06/14] spapr_iommu: Introduce "enabled" state for TCE table List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini , David Gibson Cc: Michael Roth , Alex Williamson , qemu-ppc@nongnu.org, qemu-devel@nongnu.org, Alexander Graf On 05/26/2015 11:48 PM, Paolo Bonzini wrote: > > > On 26/05/2015 15:42, Alexey Kardashevskiy wrote: >> >> >> The next patch of this patchset changes: >> spapr_tce_table_do_enable() >> memory_region_init_iommu(&iommu) >> memory_region_add_subregion(&root, &iommu) >> >> spapr_tce_table_disable() >> memory_region_del_subregion(&root, &iommu) >> object_unref(&iommu) >> >> These spapr_tce_xxx are called by request from the guest. &root is a >> container and exists as long as sPAPRTCETable exists. >> >> Where do I get a leaking child property here? > > When you unref iommu and not unparent it. The next > memory_region_init_iommu creates a second child property, and the first > is gone. But when do I get this child property? In memory_region_add_subregion()? And memory_region_del_subregion() does not do the opposite thing (unparent)? > What is different between the various IOMMU regions, so that you cannot > create just one? There are two DMA windows on the same PCI bus (in hardware too), at different offset and with a different page size. -- Alexey