diff options
| author |   Vitaly Kuznetsov <vkuznets@redhat.com> | 2025-12-22 15:46:46 +0100 |
|---|---|---|
| committer |   Jason A. Donenfeld <Jason@zx2c4.com> | 2025-12-22 16:18:54 +0100 |
| commit | bb9ff576fdff48c242876f55098a3ee20a29df5d (patch) | |
| tree | 65a9ef062fdcab046fa9d4624fcafdbdbe42f150 /drivers | |
| parent | Merge tag 'random-6.19-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random (diff) | |
| download | linux-rng-master.tar.xz linux-rng-master.zip | |
It was found that AWS SEV-SNP enabled instances are not able to boot with
commit 81256a50aa0f ("x86/mm: Make memremap(MEMREMAP_WB) map memory as
encrypted by default") applied and the reason seems to be the vmgenid
device which requires unencrypted writeable memory.
A similar problem was previously fixed in DRM with commit
7dfede7d7edd ("drm/vmwgfx: Fix guests running with TDX/SEV").
Note, trusting vmgenid device in a Confidential VM is questionable: the
malicious host may intentionally avoid notifying the guest when a copy is
created.
Fixes: 81256a50aa0f ("x86/mm: Make memremap(MEMREMAP_WB) map memory as encrypted by default")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: stable@vger.kernel.org # 6.15+
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/virt/vmgenid.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/virt/vmgenid.c b/drivers/virt/vmgenid.c index 66135eac3abf..2cf0096aa217 100644 --- a/drivers/virt/vmgenid.c +++ b/drivers/virt/vmgenid.c @@ -75,7 +75,8 @@ static int vmgenid_add_acpi(struct device *dev, struct vmgenid_state *state) phys_addr = (obj->package.elements[0].integer.value << 0) | (obj->package.elements[1].integer.value << 32); - virt_addr = devm_memremap(&device->dev, phys_addr, VMGENID_SIZE, MEMREMAP_WB); + virt_addr = devm_memremap(&device->dev, phys_addr, VMGENID_SIZE, + MEMREMAP_WB | MEMREMAP_DEC); if (IS_ERR(virt_addr)) { ret = PTR_ERR(virt_addr); goto out; |