[PATCH 00/17] Fixes and Cleanups for the Intel VT-d driver

Li, ZhenHua zhen-hual at hp.com
Mon Jun 8 01:06:45 PDT 2015

Finished testing on my HP huge system, SuperDome X.
It works well.


On 06/05/2015 10:10 PM, Joerg Roedel wrote:
> Hey,
> here are a couple of patches to fix the fall-out from the
> patch set fixing the kdump faults with VT-d enabled. A few
> important issues have been fixed:
> 	* Moved sleeping functions out of atomic sections,
> 	  mainly iremap_cache/iounmap.
> 	* Mark domain ids used in the old kernel as reserved
> 	  in the kdump kernel, so that any new domains don't
> 	  interfere with domains from the old kernel
> 	* Mark all IRT entries from the old kernel as
> 	  reservered in the new kernel, so that we don't
> 	  overwrite an entry which might still be in use by
> 	  a device
> 	* Only try to load anything from the old kernel when
> 	  we are in a kdump kernel. If we find the iommu
> 	  hardware enabled and we are not in a kdump kernel,
> 	  just disable the iommu and proceed with
> 	  initialization.
> 	* Fix a compile error
> Besides that I also cleaned up the code to simplify it:
> 	* Move necessary initialization steps before the
> 	  root entry table and the irq remapping table is
> 	  programmed into hardware. This makes sure QI is
> 	  initialized so that we can flush the iommu caches
> 	  when hardware got the new tables.
> 	* Make the new root entry table and irq remapping
> 	  table visible to hardware immediatly after they
> 	  are created and loaded with the data from the old
> 	  kernel. This allows to remove the code to update
> 	  both, the old and the new version of the table at
> 	  the same time.
> 	* Clean up log messages from the VT-d driver to have
> 	  a common prefix that can be grepped for.
> 	* Remove unused code
> The changes have been tested by me an Baoquan He. I'll plan
> to put them into the x86/vt-d branch for v4.2.
> Regards,
> 	Joerg
> Joerg Roedel (17):
>    iommu/vt-d: Fix compile error when CONFIG_INTEL_IOMMU=n
>    iommu/vt-d: Remove __iommu_save_to_oldmem() function
>    iommu/vt-d: Make two functions static
>    iommu/vt-d: Load old data structures only in kdump kernel
>    iommu/vt-d: Mark root-entry present in set_root_entry
>    iommu/vt-d: Rework loading of old root-entry table
>    iommu/vt-d: Copy context-tables outside of spin_lock
>    iommu/vt-d: Don't reuse domain-ids from old kernel
>    iommu/vt-d: Clean up log messages in intel-iommu.c
>    iommu/vt-d: Allocate irq remapping table bitmap with GFP_KERNEL
>    iommu/vt-d: Move QI initialization to intel_setup_irq_remapping
>    iommu/vt-d: Move EIM detection to intel_prepare_irq_remapping
>    iommu/vt-d: Split up iommu_set_irq_remapping
>    iommu/vt-d: Move kdump pointer intialization to __iommu_load_old_irte
>    iommu/vt-d: Mark irt entries from old kernel as allocated
>    iommu/vt-d: Copy old irte in intel_setup_irq_remapping
>    iommu/vt-d: Remove update code for old ir-table
>   drivers/iommu/dmar.c                |  26 +-
>   drivers/iommu/intel-iommu.c         | 463 ++++++++++++++----------------------
>   drivers/iommu/intel_irq_remapping.c | 263 +++++++++-----------
>   include/linux/intel-iommu.h         |  17 +-
>   4 files changed, 299 insertions(+), 470 deletions(-)

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