2010-12-01 06:56:10

by Suresh Siddha

Subject: [patch 4/4] vt-d: handle previous faults after enabling fault handling

Fault handling is getting enabled after enabling the interrupt-remapping (as
the success of interrupt-remapping can affect the apic mode and hence the
fault handling mode).

Hence there can potentially be some faults between the window of enabling
interrupt-remapping in the vt-d and the fault-handling of the vt-d units.

Handle any previous faults after enabling the vt-d fault handling.

For v2.6.38 cleanup, need to check if we can remove the dmar_fault() in the
enable_intr_remapping() and see if we can enable fault handling along with
enabling intr-remapping.

Signed-off-by: Suresh Siddha <[email protected]>
Cc: [email protected] [v2.6.32+]
---
drivers/pci/dmar.c | 5 +++++
1 file changed, 5 insertions(+)

Index: tip/drivers/pci/dmar.c
===================================================================
--- tip.orig/drivers/pci/dmar.c
+++ tip/drivers/pci/dmar.c
@@ -1417,6 +1417,11 @@ int __init enable_drhd_fault_handling(vo
(unsigned long long)drhd->reg_base_addr, ret);
return -1;
}
+
+ /*
+ * Clear any previous faults.
+ */
+ dmar_fault(iommu->irq, iommu);
}

return 0;

2010-12-01 08:53:49

by Chris Wright

Subject: Re: [patch 4/4] vt-d: handle previous faults after enabling fault handling

* Suresh Siddha ([email protected]) wrote:
> Fault handling is getting enabled after enabling the interrupt-remapping (as
> the success of interrupt-remapping can affect the apic mode and hence the
> fault handling mode).
>
> Hence there can potentially be some faults between the window of enabling
> interrupt-remapping in the vt-d and the fault-handling of the vt-d units.
>
> Handle any previous faults after enabling the vt-d fault handling.
>
> For v2.6.38 cleanup, need to check if we can remove the dmar_fault() in the
> enable_intr_remapping() and see if we can enable fault handling along with
> enabling intr-remapping.
>
> Signed-off-by: Suresh Siddha <[email protected]>

Acked-by: Chris Wright <[email protected]>

2010-12-14 01:17:22

by Suresh Siddha

Subject: [tip:x86/urgent] x86, vt-d: Handle previous faults after enabling fault handling

Commit-ID: 7f99d946e71e71d484b7543b49e990508e70d0c0
Gitweb: http://git.kernel.org/tip/7f99d946e71e71d484b7543b49e990508e70d0c0
Author: Suresh Siddha <[email protected]>
AuthorDate: Tue, 30 Nov 2010 22:22:29 -0800
Committer: H. Peter Anvin <[email protected]>
CommitDate: Mon, 13 Dec 2010 16:53:57 -0800

x86, vt-d: Handle previous faults after enabling fault handling

Fault handling is getting enabled after enabling the interrupt-remapping (as
the success of interrupt-remapping can affect the apic mode and hence the
fault handling mode).

Hence there can potentially be some faults between the window of enabling
interrupt-remapping in the vt-d and the fault-handling of the vt-d units.

Handle any previous faults after enabling the vt-d fault handling.

For v2.6.38 cleanup, need to check if we can remove the dmar_fault() in the
enable_intr_remapping() and see if we can enable fault handling along with
enabling intr-remapping.

Signed-off-by: Suresh Siddha <[email protected]>
LKML-Reference: <[email protected]>
Cc: [email protected] [v2.6.32+]
Acked-by: Chris Wright <[email protected]>
Signed-off-by: H. Peter Anvin <[email protected]>
---
drivers/pci/dmar.c | 5 +++++
1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/dmar.c b/drivers/pci/dmar.c
index 0157708..09933eb 100644
--- a/drivers/pci/dmar.c
+++ b/drivers/pci/dmar.c
@@ -1417,6 +1417,11 @@ int __init enable_drhd_fault_handling(void)
(unsigned long long)drhd->reg_base_addr, ret);
return -1;
}
+
+ /*
+ * Clear any previous faults.
+ */
+ dmar_fault(iommu->irq, iommu);
}

return 0;