From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932199AbcITMuI (ORCPT ); Tue, 20 Sep 2016 08:50:08 -0400 Received: from 8bytes.org ([81.169.241.247]:34506 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751040AbcITMuG (ORCPT ); Tue, 20 Sep 2016 08:50:06 -0400 Date: Tue, 20 Sep 2016 14:50:04 +0200 From: Joerg Roedel To: Baoquan He Cc: iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, kexec@lists.infradead.org, dyoung@redhat.com, xlpang@redhat.com, Vincent.Wan@amd.com Subject: Re: [PATCH v5 7/8] iommu/amd: Don't update domain info to dte entry at iommu init stage Message-ID: <20160920125004.GF3541@8bytes.org> References: <1473951806-25511-1-git-send-email-bhe@redhat.com> <1473951806-25511-8-git-send-email-bhe@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1473951806-25511-8-git-send-email-bhe@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Sep 15, 2016 at 11:03:25PM +0800, Baoquan He wrote: > AMD iommu creates protection domain and assign each device to it during > iommu driver initialization stage. This happened just after system pci > bus scanning stage, and much earlier than device driver init stage. So > at this time if in kdump kernel the domain info, especially pte_root, > can't be updated to dte entry. We should wait until device driver init > stage. > > Signed-off-by: Baoquan He > --- > drivers/iommu/amd_iommu.c | 18 ++++++++++++++++++ > 1 file changed, 18 insertions(+) > > diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c > index fcb69ff..6c37300 100644 > --- a/drivers/iommu/amd_iommu.c > +++ b/drivers/iommu/amd_iommu.c > @@ -137,6 +137,7 @@ struct iommu_dev_data { > bool pri_tlp; /* PASID TLB required for > PPR completions */ > u32 errata; /* Bitmap for errata to apply */ > + bool domain_updated; > }; > > /* > @@ -1708,6 +1709,15 @@ static void set_dte_entry(u16 devid, struct protection_domain *domain, bool ats) > { > u64 pte_root = 0; > u64 flags = 0; > + struct iommu_dev_data *dev_data; > + struct amd_iommu *iommu = amd_iommu_rlookup_table[devid]; > + > + dev_data = find_dev_data(devid); > + if (!dev_data) > + return; > + > + if (translation_pre_enabled(iommu) && !dev_data->domain_updated) > + return; > > if (domain->mode != PAGE_MODE_NONE) > pte_root = virt_to_phys(domain->pt_root); > @@ -1756,6 +1766,14 @@ static void set_dte_entry(u16 devid, struct protection_domain *domain, bool ats) > > static void clear_dte_entry(u16 devid) > { > + struct iommu_dev_data *dev_data; > + struct amd_iommu *iommu = amd_iommu_rlookup_table[devid]; > + > + dev_data = find_dev_data(devid); > + if (!dev_data) > + return; > + if (translation_pre_enabled(iommu) && !dev_data->domain_updated) > + return; This should be moved to do_attach/do_detach. There you also already have the dev_data you need here. > /* remove entry from the device table seen by the hardware */ > amd_iommu_dev_table[devid].data[0] = DTE_FLAG_V | DTE_FLAG_TV; > amd_iommu_dev_table[devid].data[1] &= DTE_FLAG_MASK; > -- > 2.5.5 >