From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753973AbdFVWyT (ORCPT ); Thu, 22 Jun 2017 18:54:19 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51906 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753919AbdFVWyS (ORCPT ); Thu, 22 Jun 2017 18:54:18 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 89195120D7 Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=alex.williamson@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 89195120D7 Date: Thu, 22 Jun 2017 16:54:16 -0600 From: Alex Williamson To: Jacob Pan Cc: iommu@lists.linux-foundation.org, LKML , Joerg Roedel , David Woodhouse , "Liu, Yi L" , Lan Tianyu , "Tian, Kevin" , Raj Ashok , Jean Delvare Subject: Re: [RFC 7/9] iommu/dmar: notify unrecoverable faults Message-ID: <20170622165416.6ea718f1@w520.home> In-Reply-To: <1497478983-77580-8-git-send-email-jacob.jun.pan@linux.intel.com> References: <1497478983-77580-1-git-send-email-jacob.jun.pan@linux.intel.com> <1497478983-77580-8-git-send-email-jacob.jun.pan@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Thu, 22 Jun 2017 22:54:17 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 14 Jun 2017 15:23:01 -0700 Jacob Pan wrote: > Currently, when device DMA faults are detected by IOMMU the fault > reasons are printed but the offending device is not notified. > This patch allows device drivers to be optionally notified for fault > conditions when device specific handling is needed for more subtle > processing, e.g. request with PASID transactions. > > Signed-off-by: Jacob Pan > Signed-off-by: Ashok Raj > --- > drivers/iommu/dmar.c | 37 ++++++++++++++++++++++++++++++++++++- > 1 file changed, 36 insertions(+), 1 deletion(-) > > diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c > index cbf7763..2c0b80d464 100644 > --- a/drivers/iommu/dmar.c > +++ b/drivers/iommu/dmar.c > @@ -1587,11 +1587,43 @@ void dmar_msi_read(int irq, struct msi_msg *msg) > raw_spin_unlock_irqrestore(&iommu->register_lock, flag); > } > > +static int dmar_unrecov_fault_notify(u8 fault_reason, u16 source_id, > + unsigned long long addr) > +{ > + int ret; > + struct pci_dev *pdev; > + struct iommu_fault_event *event; > + > + pdev = pci_get_bus_and_slot(source_id >> 8, source_id & 0xFF); > + if (!pdev) > + return -ENODEV; > + pr_debug("Notify PCI device fault [%02x:%02x.%d]\n", > + source_id >> 8, PCI_SLOT(source_id & 0xff), > + PCI_FUNC(source_id & 0xff)); > + event = kzalloc(sizeof(*event) + sizeof(fault_reason), GFP_KERNEL); > + if (!event) > + return -ENOMEM; Leaks pdev reference. > + > + pci_dev_get(pdev); > + event->dev = &pdev->dev; > + event->buf[0] = fault_reason; > + event->addr = addr; > + event->length = sizeof(fault_reason); > + event->flags = IOMMU_FAULT_UNRECOV; > + ret = iommu_fault_notifier_call_chain(event); > + > + pci_dev_put(pdev); > + kfree(event); > + > + return ret; > +} > + > static int dmar_fault_do_one(struct intel_iommu *iommu, int type, > u8 fault_reason, u16 source_id, unsigned long long addr) > { > const char *reason; > int fault_type; > + int ret = 0; > > reason = dmar_get_fault_reason(fault_reason, &fault_type); > > @@ -1600,11 +1632,14 @@ static int dmar_fault_do_one(struct intel_iommu *iommu, int type, > source_id >> 8, PCI_SLOT(source_id & 0xFF), > PCI_FUNC(source_id & 0xFF), addr >> 48, > fault_reason, reason); > - else > + else { > pr_err("[%s] Request device [%02x:%02x.%d] fault addr %llx [fault reason %02d] %s\n", > type ? "DMA Read" : "DMA Write", > source_id >> 8, PCI_SLOT(source_id & 0xFF), > PCI_FUNC(source_id & 0xFF), addr, fault_reason, reason); > + ret = dmar_unrecov_fault_notify(fault_reason, source_id, addr); For what purpose are we recording this return code? > + } > + > return 0; > } >