* [PATCH 4.18 156/168] iommu/amd: Clear memory encryption mask from physical address
[not found] ` <20181008175620.043587728-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org>
@ 2018-10-08 18:32 ` Greg Kroah-Hartman
0 siblings, 0 replies; only message in thread
From: Greg Kroah-Hartman @ 2018-10-08 18:32 UTC (permalink / raw)
To: linux-kernel-u79uwXL29TY76Z2rM5mHXA
Cc: Tom Lendacky, Joerg Roedel, Brijesh Singh,
kvm-u79uwXL29TY76Z2rM5mHXA, Radim Krčmář,
Greg Kroah-Hartman, stable-u79uwXL29TY76Z2rM5mHXA,
iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA, Paolo Bonzini,
Boris Ostrovsky, Borislav Petkov
4.18-stable review patch. If anyone has any objections, please let me know.
------------------
From: Singh, Brijesh <brijesh.singh@amd.com>
commit b3e9b515b08e407ab3a026dc2e4d935c48d05f69 upstream.
Boris Ostrovsky reported a memory leak with device passthrough when SME
is active.
The VFIO driver uses iommu_iova_to_phys() to get the physical address for
an iova. This physical address is later passed into vfio_unmap_unpin() to
unpin the memory. The vfio_unmap_unpin() uses pfn_valid() before unpinning
the memory. The pfn_valid() check was failing because encryption mask was
part of the physical address returned. This resulted in the memory not
being unpinned and therefore leaked after the guest terminates.
The memory encryption mask must be cleared from the physical address in
iommu_iova_to_phys().
Fixes: 2543a786aa25 ("iommu/amd: Allow the AMD IOMMU to work with memory encryption")
Reported-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: <iommu@lists.linux-foundation.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: kvm@vger.kernel.org
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: <stable@vger.kernel.org> # 4.14+
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/iommu/amd_iommu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -3073,7 +3073,7 @@ static phys_addr_t amd_iommu_iova_to_phy
return 0;
offset_mask = pte_pgsize - 1;
- __pte = *pte & PM_ADDR_MASK;
+ __pte = __sme_clr(*pte & PM_ADDR_MASK);
return (__pte & ~offset_mask) | (iova & offset_mask);
}
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
^ permalink raw reply [flat|nested] only message in thread