This is a note to let you know that I've just added the patch titled
iommu/vt-d: Make Intel SVM code 64-bit only
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
iommu-vt-d-make-intel-svm-code-64-bit-only.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 9486727f5981a5ec5c0b699fb1777451bd6786e4 Mon Sep 17 00:00:00 2001
From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Date: Tue, 23 Jun 2020 07:13:40 +0800
Subject: iommu/vt-d: Make Intel SVM code 64-bit only
From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
commit 9486727f5981a5ec5c0b699fb1777451bd6786e4 upstream.
Current Intel SVM is designed by setting the pgd_t of the processor page
table to FLPTR field of the PASID entry. The first level translation only
supports 4 and 5 level paging structures, hence it's infeasible for the
IOMMU to share a processor's page table when it's running in 32-bit mode.
Let's disable 32bit support for now and claim support only when all the
missing pieces are ready in the future.
Fixes: 1c4f88b7f1f92 ("iommu/vt-d: Shared virtual address in scalable mode")
Suggested-by: Joerg Roedel <jroedel@xxxxxxx>
Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20200622231345.29722-2-baolu.lu@xxxxxxxxxxxxxxx
Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/iommu/Kconfig | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -205,7 +205,7 @@ config INTEL_IOMMU_DEBUGFS
config INTEL_IOMMU_SVM
bool "Support for Shared Virtual Memory with Intel IOMMU"
- depends on INTEL_IOMMU && X86
+ depends on INTEL_IOMMU && X86_64
select PCI_PASID
select MMU_NOTIFIER
help
Patches currently in stable-queue which might be from baolu.lu@xxxxxxxxxxxxxxx are
queue-5.4/iommu-vt-d-make-intel-svm-code-64-bit-only.patch
