[PATCH 2/2] iommu: add warning when sharing groups

From	Sinan Kaya <okaya@codeaurora.org>
Newsgroups	linux.kernel
Subject	[PATCH 2/2] iommu: add warning when sharing groups
Date	2017-02-14 22:30 +0100
Message-ID	<taSPE-72f-1@gated-at.bofh.it> (permalink)
References	<taSPE-72f-3@gated-at.bofh.it>
Organization	linux.* mail to news gateway

Show all headers | View raw

The ACS requirement has been obscured in the current code and is only
known by certain individuals who happen to read the code. Print out a
warning with ACS path failure when ACS requirement is not met.

Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
---
 drivers/iommu/iommu.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index dbe7f65..049ee0a 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -811,6 +811,9 @@ struct iommu_group *pci_device_group(struct device *dev)
 	if (IS_ERR(group))
 		return NULL;
 
+	if (pci_is_root_bus(bus))
+		dev_warn_once(&pdev->dev, "using shared group due to ACS path failure\n");
+
 	return group;
 }
 
-- 
1.9.1

Back to linux.kernel | Previous | Next — Next in thread | Find similar | Unroll thread

Thread

[PATCH 2/2] iommu: add warning when sharing groups Sinan Kaya <okaya@codeaurora.org> - 2017-02-14 22:30 +0100
  Re: [PATCH 2/2] iommu: add warning when sharing groups Alex Williamson <alex.williamson@redhat.com> - 2017-02-15 01:00 +0100
    Re: [PATCH 2/2] iommu: add warning when sharing groups okaya@codeaurora.org - 2017-02-15 05:00 +0100
      Re: [PATCH 2/2] iommu: add warning when sharing groups Alex Williamson <alex.williamson@redhat.com> - 2017-02-15 20:40 +0100
        Re: [PATCH 2/2] iommu: add warning when sharing groups Sinan Kaya <okaya@codeaurora.org> - 2017-02-15 22:50 +0100
          Re: [PATCH 2/2] iommu: add warning when sharing groups Sinan Kaya <okaya@codeaurora.org> - 2017-02-16 23:20 +0100

csiph-web