linux/include/uapi
Lu Baolu 03476e687e iommu/vt-d: Disallow read-only mappings to nest parent domain
When remapping hardware is configured by system software in scalable mode
as Nested (PGTT=011b) and with PWSNP field Set in the PASID-table-entry,
it may Set Accessed bit and Dirty bit (and Extended Access bit if enabled)
in first-stage page-table entries even when second-stage mappings indicate
that corresponding first-stage page-table is Read-Only.

As the result, contents of pages designated by VMM as Read-Only can be
modified by IOMMU via PML5E (PML4E for 4-level tables) access as part of
address translation process due to DMAs issued by Guest.

This disallows read-only mappings in the domain that is supposed to be used
as nested parent. Reference from Sapphire Rapids Specification Update [1],
errata details, SPR17. Userspace should know this limitation by checking
the IOMMU_HW_INFO_VTD_ERRATA_772415_SPR17 flag reported in the IOMMU_GET_HW_INFO
ioctl.

[1] https://www.intel.com/content/www/us/en/content-details/772415/content-details.html

Link: https://lore.kernel.org/r/20231026044216.64964-9-yi.l.liu@intel.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2023-10-26 11:16:34 -03:00
..
asm-generic Add x86 shadow stack support 2023-08-31 12:20:12 -07:00
drm drm/nouveau: uapi: don't pass NO_PREFETCH flag implicitly 2023-08-24 02:57:50 +02:00
linux iommu/vt-d: Disallow read-only mappings to nest parent domain 2023-10-26 11:16:34 -03:00
misc habanalabs/uapi: move uapi file to drm 2023-01-26 10:56:23 +02:00
mtd This pull request contains updates for UBI and UBIFS 2022-10-14 18:23:23 -07:00
rdma RDMA/irdma: Use HW specific minimum WQ size 2023-07-30 15:43:00 +03:00
scsi Merge branch 'fixes' into misc 2023-09-02 08:25:19 +01:00
sound ASoC: SOF: topology: Add a token for dropping widget name in kcontrol name 2023-08-15 13:25:56 +01:00
video
xen xen: privcmd: Add support for irqfd 2023-08-22 12:12:50 +02:00
Kbuild