All of lore.kernel.org
 help / color / mirror / Atom feed
From: jimyan <jimyan@baidu.com>
To: joro@8bytes.org, jsnitsel@redhat.com, baolu.lu@linux.intel.com,
	roland@purestorage.com, hch@infradead.org
Cc: iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org,
	jimyan@baidu.com
Subject: [PATCH v3] iommu/vt-d: Don't reject Host Bridge due to scope mismatch
Date: Fri, 10 Jan 2020 17:58:03 +0800	[thread overview]
Message-ID: <1578650283-17245-1-git-send-email-jimyan@baidu.com> (raw)

On a system with two host bridges(0000:00:00.0,0000:80:00.0), iommu
initialization fails with

    DMAR: Device scope type does not match for 0000:80:00.0

This is because the DMAR table reports this device as having scope 2
(ACPI_DMAR_SCOPE_TYPE_BRIDGE):

but the device has a type 0 PCI header:
80:00.0 Class 0600: Device 8086:2020 (rev 06)
00: 86 80 20 20 47 05 10 00 06 00 00 06 10 00 00 00
10: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
20: 00 00 00 00 00 00 00 00 00 00 00 00 86 80 00 00
30: 00 00 00 00 90 00 00 00 00 00 00 00 00 01 00 00

VT-d works perfectly on this system, so there's no reason to bail out
on initialization due to this apparent scope mismatch. Add the class
0x06 ("PCI_BASE_CLASS_BRIDGE") as a heuristic for allowing DMAR
initialization for non-bridge PCI devices listed with scope bridge.

Signed-off-by: jimyan <jimyan@baidu.com>
---
 drivers/iommu/dmar.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index eecd6a421667..50c92eb23ee4 100644
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -244,7 +244,7 @@ int dmar_insert_dev_scope(struct dmar_pci_notify_info *info,
 		     info->dev->hdr_type != PCI_HEADER_TYPE_NORMAL) ||
 		    (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_BRIDGE &&
 		     (info->dev->hdr_type == PCI_HEADER_TYPE_NORMAL &&
-		      info->dev->class >> 8 != PCI_CLASS_BRIDGE_OTHER))) {
+		      info->dev->class >> 16 != PCI_BASE_CLASS_BRIDGE))) {
 			pr_warn("Device scope type does not match for %s\n",
 				pci_name(info->dev));
 			return -EINVAL;
-- 
2.11.0


WARNING: multiple messages have this Message-ID (diff)
From: jimyan <jimyan@baidu.com>
To: joro@8bytes.org, jsnitsel@redhat.com, baolu.lu@linux.intel.com,
	roland@purestorage.com, hch@infradead.org
Cc: jimyan@baidu.com, iommu@lists.linux-foundation.org,
	linux-kernel@vger.kernel.org
Subject: [PATCH v3] iommu/vt-d: Don't reject Host Bridge due to scope mismatch
Date: Fri, 10 Jan 2020 17:58:03 +0800	[thread overview]
Message-ID: <1578650283-17245-1-git-send-email-jimyan@baidu.com> (raw)

On a system with two host bridges(0000:00:00.0,0000:80:00.0), iommu
initialization fails with

    DMAR: Device scope type does not match for 0000:80:00.0

This is because the DMAR table reports this device as having scope 2
(ACPI_DMAR_SCOPE_TYPE_BRIDGE):

but the device has a type 0 PCI header:
80:00.0 Class 0600: Device 8086:2020 (rev 06)
00: 86 80 20 20 47 05 10 00 06 00 00 06 10 00 00 00
10: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
20: 00 00 00 00 00 00 00 00 00 00 00 00 86 80 00 00
30: 00 00 00 00 90 00 00 00 00 00 00 00 00 01 00 00

VT-d works perfectly on this system, so there's no reason to bail out
on initialization due to this apparent scope mismatch. Add the class
0x06 ("PCI_BASE_CLASS_BRIDGE") as a heuristic for allowing DMAR
initialization for non-bridge PCI devices listed with scope bridge.

Signed-off-by: jimyan <jimyan@baidu.com>
---
 drivers/iommu/dmar.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index eecd6a421667..50c92eb23ee4 100644
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -244,7 +244,7 @@ int dmar_insert_dev_scope(struct dmar_pci_notify_info *info,
 		     info->dev->hdr_type != PCI_HEADER_TYPE_NORMAL) ||
 		    (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_BRIDGE &&
 		     (info->dev->hdr_type == PCI_HEADER_TYPE_NORMAL &&
-		      info->dev->class >> 8 != PCI_CLASS_BRIDGE_OTHER))) {
+		      info->dev->class >> 16 != PCI_BASE_CLASS_BRIDGE))) {
 			pr_warn("Device scope type does not match for %s\n",
 				pci_name(info->dev));
 			return -EINVAL;
-- 
2.11.0

_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

             reply	other threads:[~2020-01-10  9:58 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-01-10  9:58 jimyan [this message]
2020-01-10  9:58 ` [PATCH v3] iommu/vt-d: Don't reject Host Bridge due to scope mismatch jimyan

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1578650283-17245-1-git-send-email-jimyan@baidu.com \
    --to=jimyan@baidu.com \
    --cc=baolu.lu@linux.intel.com \
    --cc=hch@infradead.org \
    --cc=iommu@lists.linux-foundation.org \
    --cc=joro@8bytes.org \
    --cc=jsnitsel@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=roland@purestorage.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.