On Thu, Apr 01, 2010 at 06:23:53PM -0700, Chris Wright wrote:
Hit another kdump problem as reported by Neil Horman. When initializaing
the IOMMU, we attach devices to their domains before the IOMMU is
fully (re)initialized. Attaching a device will issue some important
invalidations. In the
On Thu, Apr 01, 2010 at 06:23:53PM -0700, Chris Wright wrote:
Hit another kdump problem as reported by Neil Horman. When initializaing
the IOMMU, we attach devices to their domains before the IOMMU is
fully (re)initialized. Attaching a device will issue some important
invalidations. In the
* Vivek Goyal (vgo...@redhat.com) wrote:
Following is just for my education purposes. Trying to understand better
the impact of in-flight DMAs. So IIUC, in kudmp context following seems to be
sequence of events.
1. kernel crashes, we leave IOMMU enabled.
No, we actually disable the IOMMU
Chris Wright chr...@sous-sol.org writes:
* Vivek Goyal (vgo...@redhat.com) wrote:
Following is just for my education purposes. Trying to understand better
the impact of in-flight DMAs. So IIUC, in kudmp context following seems to be
sequence of events.
1. kernel crashes, we leave IOMMU
* Joerg Roedel (j...@8bytes.org) wrote:
Ok, good to know this fixes the problem. One issue: If the
initialization of the domains fails the iommu hardware needs to be
disabled again in the free path.
Sure, thanks for catching. Will resend shortly
thanks,
-chris
Series includes the following patches:
x86/amd-iommu: enable iommu before attaching devices
x86/amd-iommu: warn when issuing command to uninitialized cmd buffer
Revert x86: disable IOMMUs on kernel crash
x86/amd-iommu: use for_each_pci_dev
First one is the primary bug fix.
v2
- add
Replace open coded version with for_each_pci_dev
Signed-off-by: Chris Wright chr...@sous-sol.org
---
arch/x86/kernel/amd_iommu.c |2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -2187,7 +2187,7 @@ static void
To catch future potential issues we can add a warning whenever we issue
a command before the command buffer is fully initialized.
Signed-off-by: Chris Wright chr...@sous-sol.org
---
Or not...this is just if you think it's useful ;-)
arch/x86/include/asm/amd_iommu_types.h |1 +
This effectively reverts commit 61d047be99757fd9b0af900d7abce9a13a337488.
Disabling the IOMMU can potetially allow DMA transactions to
complete without being translated. Leave it enabled, and allow
crash kernel to do the IOMMU reinitialization properly.
Cc: Joerg Roedel joerg.roe...@amd.com
Cc:
