From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joerg Roedel Subject: Re: [PATCH v5 7/8] iommu/amd: Don't update domain info to dte entry at iommu init stage Date: Tue, 20 Sep 2016 14:50:04 +0200 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-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1473951806-25511-8-git-send-email-bhe-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Baoquan He Cc: kexec-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Vincent.Wan-5C7GfCeVMHo@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, dyoung-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org List-Id: iommu@lists.linux-foundation.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 >