Niklas Schnelle 895c0747f7 vfio/type1: Respect IOMMU reserved regions in vfio_test_domain_fgsp() ... Since commit cbf7827bc5 ("iommu/s390: Fix potential s390_domain aperture shrinking") the s390 IOMMU driver uses reserved regions for the system provided DMA ranges of PCI devices. Previously it reduced the size of the IOMMU aperture and checked it on each mapping operation. On current machines the system denies use of DMA addresses below 2^32 for all PCI devices. Usually mapping IOVAs in a reserved regions is harmless until a DMA actually tries to utilize the mapping. However on s390 there is a virtual PCI device called ISM which is implemented in firmware and used for cross LPAR communication. Unlike real PCI devices this device does not use the hardware IOMMU but inspects IOMMU translation tables directly on IOTLB flush (s390 RPCIT instruction). If it detects IOVA mappings outside the allowed ranges it goes into an error state. This error state then causes the device to be unavailable to the KVM guest. Analysing this we found that vfio_test_domain_fgsp() maps 2 pages at DMA address 0 irrespective of the IOMMUs reserved regions. Even if usually harmless this seems wrong in the general case so instead go through the freshly updated IOVA list and try to find a range that isn't reserved, and fits 2 pages, is PAGE_SIZE * 2 aligned. If found use that for testing for fine grained super pages. Fixes: af029169b8 ("vfio/type1: Check reserved region conflict and update iova list") Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20230110164427.4051938-2-schnelle@linux.ibm.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>		2023-01-10 10:44:37 -07:00
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fsl-mc	VFIO updates for v6.2-rc1	2022-12-15 13:12:15 -08:00
mdev	vfio/mdev: add mdev available instance checking to the core	2022-10-04 12:06:58 -06:00
pci	VFIO updates for v6.2-rc1	2022-12-15 13:12:15 -08:00
platform	VFIO updates for v6.2-rc1	2022-12-15 13:12:15 -08:00
container.c	vfio: Refactor dma APIs for emulated devices	2022-12-05 08:56:01 -04:00
group.c	Driver Core changes for 6.2-rc1	2022-12-16 03:54:54 -08:00
iommufd.c	vfio-iommufd: Support iommufd for emulated VFIO devices	2022-12-02 11:52:03 -04:00
iova_bitmap.c	vfio/iova_bitmap: refactor iova_bitmap_set() to better handle page boundaries	2022-12-02 10:09:25 -07:00
Kconfig	VFIO updates for v6.2-rc1	2022-12-15 13:12:15 -08:00
Makefile	VFIO updates for v6.2-rc1	2022-12-15 13:12:15 -08:00
vfio_iommu_spapr_tce.c	vfio: Move vfio_spapr_iommu_eeh_ioctl into vfio_iommu_spapr_tce.c	2022-12-05 12:04:32 -07:00
vfio_iommu_type1.c	vfio/type1: Respect IOMMU reserved regions in vfio_test_domain_fgsp()	2023-01-10 10:44:37 -07:00
vfio_main.c	VFIO updates for v6.2-rc1	2022-12-15 13:12:15 -08:00
vfio.h	VFIO updates for v6.2-rc1	2022-12-15 13:12:15 -08:00
virqfd.c	vfio: Fold vfio_virqfd.ko into vfio.ko	2022-12-05 12:04:32 -07:00