Hi,Um, I'm missing context, but the only thing I recall saying no to wrt RMRR
On 15/11/2016 14:09, Eric Auger wrote:
Following LPC discussions, we now report reserved regions through
iommu-group sysfs reserved_regions attribute file.
While I am respinning this series into v4, here is a tentative summary
of technical topics for which no consensus was reached at this point.
1) Shall we report the usable IOVA range instead of reserved IOVA
ranges. Not discussed at/after LPC.
x I currently report reserved regions. Alex expressed the need to
report the full usable IOVA range instead (x86 min-max range
minus MSI APIC window). I think this is meaningful for ARM
too where arm-smmu might not support the full 64b range.
x Any objection we report the usable IOVA regions instead?
2) Shall the kernel check collision with MSI window* when userspace
Joerg/Will No; Alex yes
*for IOVA regions consumed downstream to the IOMMU: everyone says NO
3) RMRR reporting in the iommu group sysfs? Joerg: yes; Don: no
My current series does not expose them in iommu group sysfs.This sentence doesn't make sense to me.
I understand we can expose the RMRR regions in the iomm group sysfs
without necessarily supporting RMRR requiring device assignment.
We can also add this support later.
Reserved regions are populated through the IOMMU get_resv_region callback
(former get_dm_regions), now implemented by amd-iommu, intel-iommu and
The intel-iommu reports the [FEE0_0000h - FEF0_000h] MSI window as an
IOMMU_RESV_NOMAP reserved region.
arm-smmu reports the MSI window (arbitrarily located at 0x8000000 and
1MB large) and the PCI host bridge windows.
The series integrates a not officially posted patch from Robin:
"iommu/dma: Allow MSI-only cookies".
This series currently does not address IRQ safety assessment.
Git: complete series available at
RFC v2 -> v3:
- switch to an iommu-group sysfs API
- use new dummy allocator provided by Robin
- dummy allocator initialized by vfio-iommu-type1 after enumerating
the reserved regions
- at the moment ARM MSI base address/size is left unchanged compared
- we currently report reserved regions and not usable IOVA regions as
requested by Alex
RFC v1 -> v2:
- fix intel_add_reserved_regions
- add mutex lock/unlock in vfio_iommu_type1
Eric Auger (10):
iommu/dma: Allow MSI-only cookies
iommu: Rename iommu_dm_regions into iommu_resv_regions
iommu: Add new reserved IOMMU attributes
iommu: Do not map reserved regions
iommu: Implement reserved_regions iommu-group sysfs file
iommu/vt-d: Implement reserved region get/put callbacks
iommu/arm-smmu: Implement reserved region get/put callbacks
vfio/type1: Get MSI cookie
drivers/iommu/amd_iommu.c | 20 +++---
drivers/iommu/arm-smmu.c | 52 +++++++++++++++
drivers/iommu/dma-iommu.c | 116 ++++++++++++++++++++++++++-------
drivers/iommu/intel-iommu.c | 50 ++++++++++----
drivers/iommu/iommu.c | 141 ++++++++++++++++++++++++++++++++++++----
drivers/vfio/vfio_iommu_type1.c | 26 ++++++++
include/linux/dma-iommu.h | 7 ++
include/linux/iommu.h | 49 ++++++++++----
8 files changed, 391 insertions(+), 70 deletions(-)