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Commit 0c5f6c0d authored by Lu Baolu's avatar Lu Baolu Committed by Joerg Roedel
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iommu/vt-d: Fix kdump kernels boot failure with scalable mode



The translation table copying code for kdump kernels is currently based
on the extended root/context entry formats of ECS mode defined in older
VT-d v2.5, and doesn't handle the scalable mode formats. This causes
the kexec capture kernel boot failure with DMAR faults if the IOMMU was
enabled in scalable mode by the previous kernel.

The ECS mode has already been deprecated by the VT-d spec since v3.0 and
Intel IOMMU driver doesn't support this mode as there's no real hardware
implementation. Hence this converts ECS checking in copying table code
into scalable mode.

The existing copying code consumes a bit in the context entry as a mark
of copied entry. It needs to work for the old format as well as for the
extended context entries. As it's hard to find such a common bit for both
legacy and scalable mode context entries. This replaces it with a per-
IOMMU bitmap.

Fixes: 7373a8cc ("iommu/vt-d: Setup context and enable RID2PASID support")
Cc: stable@vger.kernel.org
Reported-by: default avatarJerry Snitselaar <jsnitsel@redhat.com>
Tested-by: default avatarWen Jin <wen.jin@intel.com>
Signed-off-by: default avatarLu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20220817011035.3250131-1-baolu.lu@linux.intel.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent 94a568ce
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