KVM: SEV: Do cache maintenance on the source VM during intra-host migrationgrafted

Manually perform cache maintenance on the source VM during intra-host
migration to ensure no stale data is left in CPU caches after the VM is
destroyed.  Because the source VM is "converted" to a non-SEV VM, KVM's
memory reclaim flows won't trigger cache maintenance, e.g. when all guest
memory is reclaimed in response to detaching from the mmu_notifier.

Note, relying on the destination VM to do cache maintenance isn't an option
as KVM doesn't require identical guest memory configurations, i.e. the
source VM may have access to memory that the destination VM does not.
Enforcing equivalent memory configurations is infeasible, as it would
require a *deep* comparison of memslots, e.g. to verify that not only are
the memslot identical, but what the memslots point at is also identical.

Fixes: b56639318bb2 ("KVM: SEV: Add support for SEV intra host migration")
Cc: stable@vger.kernel.org
Reported-by: Stefan Teodorescu <fane@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20260923163721.1584779-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 120 insertions, 0 deletions

diff --git a/Documentation/ABI/testing/sysfs-driver-ccp b/Documentation/ABI/testing/sysfs-driver-ccp
new file mode 100644
index 000000000..6ec74b9a2
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-driver-ccp
@@ -0,0 +1,120 @@
+What:		/sys/bus/pci/devices/<BDF>/fused_part
+Date:		June 2022
+KernelVersion:	5.19
+Contact:	mario.limonciello@amd.com
+Description:
+		The /sys/bus/pci/devices/<BDF>/fused_part file reports
+		whether the CPU or APU has been fused to prevent tampering.
+		0: Not fused
+		1: Fused
+
+What:		/sys/bus/pci/devices/<BDF>/boot_integrity
+Date:		April 2026
+KernelVersion:	6.20
+Contact:	mario.limonciello@amd.com
+Description:
+		The /sys/bus/pci/devices/<BDF>/boot_integrity reports
+		whether the AMD CPU or APU is used for a hardware root of trust
+		during the boot process.
+		Possible values:
+		0: Not hardware root of trust.
+		1: Hardware root of trust
+
+		NOTE: Vendors may provide design specific alternative hardware
+		root of trust implementations.
+
+What:		/sys/bus/pci/devices/<BDF>/debug_lock_on
+Date:		June 2022
+KernelVersion:	5.19
+Contact:	mario.limonciello@amd.com
+Description:
+		The /sys/bus/pci/devices/<BDF>/debug_lock_on reports
+		whether the AMD CPU or APU has been unlocked for debugging.
+		Possible values:
+		0: Not locked
+		1: Locked
+
+What:		/sys/bus/pci/devices/<BDF>/tsme_status
+Date:		June 2022
+KernelVersion:	5.19
+Contact:	mario.limonciello@amd.com
+Description:
+		The /sys/bus/pci/devices/<BDF>/tsme_status file reports
+		the status of transparent secure memory encryption on AMD systems.
+		Possible values:
+		0: Not active
+		1: Active
+
+What:		/sys/bus/pci/devices/<BDF>/anti_rollback_status
+Date:		June 2022
+KernelVersion:	5.19
+Contact:	mario.limonciello@amd.com
+Description:
+		The /sys/bus/pci/devices/<BDF>/anti_rollback_status file reports
+		whether the PSP is enforcing rollback protection.
+		Possible values:
+		0: Not enforcing
+		1: Enforcing
+
+What:		/sys/bus/pci/devices/<BDF>/rpmc_production_enabled
+Date:		June 2022
+KernelVersion:	5.19
+Contact:	mario.limonciello@amd.com
+Description:
+		The /sys/bus/pci/devices/<BDF>/rpmc_production_enabled file reports
+		whether Replay Protected Monotonic Counter support has been enabled.
+		Possible values:
+		0: Not enabled
+		1: Enabled
+
+What:		/sys/bus/pci/devices/<BDF>/rpmc_spirom_available
+Date:		June 2022
+KernelVersion:	5.19
+Contact:	mario.limonciello@amd.com
+Description:
+		The /sys/bus/pci/devices/<BDF>/rpmc_spirom_available file reports
+		whether an Replay Protected Monotonic Counter supported SPI is installed
+		on the system.
+		Possible values:
+		0: Not present
+		1: Present
+
+What:		/sys/bus/pci/devices/<BDF>/hsp_tpm_available
+Date:		June 2022
+KernelVersion:	5.19
+Contact:	mario.limonciello@amd.com
+Description:
+		The /sys/bus/pci/devices/<BDF>/hsp_tpm_available file reports
+		whether the HSP TPM has been activated.
+		Possible values:
+		0: Not activated or present
+		1: Activated
+
+What:		/sys/bus/pci/devices/<BDF>/rom_armor_enforced
+Date:		June 2022
+KernelVersion:	5.19
+Contact:	mario.limonciello@amd.com
+Description:
+		The /sys/bus/pci/devices/<BDF>/rom_armor_enforced file reports
+		whether RomArmor SPI protection is enforced.
+		Possible values:
+		0: Not enforced
+		1: Enforced
+
+What:		/sys/bus/pci/devices/<BDF>/bootloader_version
+Date:		June 2023
+KernelVersion:	6.4
+Contact:	mario.limonciello@amd.com
+Description:
+		The /sys/bus/pci/devices/<BDF>/bootloader_version
+		file reports the firmware version of the AMD AGESA
+		bootloader.
+
+What:		/sys/bus/pci/devices/<BDF>/tee_version
+Date:		June 2023
+KernelVersion:	6.4
+Contact:	mario.limonciello@amd.com
+Description:
+		The /sys/bus/pci/devices/<BDF>/tee_version
+		file reports the firmware version of the AMD Trusted
+		Execution Environment (TEE).