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, 107 insertions, 0 deletions

diff --git a/Documentation/usb/linux-cdc-acm.inf b/Documentation/usb/linux-cdc-acm.inf
new file mode 100644
index 000000000..f0ffc27d4
--- /dev/null
+++ b/Documentation/usb/linux-cdc-acm.inf
@@ -0,0 +1,107 @@
+; Windows USB CDC ACM Setup File
+
+; Based on INF template which was:
+;     Copyright (c) 2000 Microsoft Corporation
+;     Copyright (c) 2007 Microchip Technology Inc.
+; likely to be covered by the MLPL as found at:
+;    <http://msdn.microsoft.com/en-us/cc300389.aspx#MLPL>.
+; For use only on Windows operating systems.
+
+[Version]
+Signature="$Windows NT$"
+Class=Ports
+ClassGuid={4D36E978-E325-11CE-BFC1-08002BE10318}
+Provider=%Linux%
+DriverVer=11/15/2007,5.1.2600.0
+
+[Manufacturer]
+%Linux%=DeviceList, NTamd64
+
+[DestinationDirs]
+DefaultDestDir=12
+
+
+;------------------------------------------------------------------------------
+;  Windows 2000/XP/Vista-32bit Sections
+;------------------------------------------------------------------------------
+
+[DriverInstall.nt]
+include=mdmcpq.inf
+CopyFiles=DriverCopyFiles.nt
+AddReg=DriverInstall.nt.AddReg
+
+[DriverCopyFiles.nt]
+usbser.sys,,,0x20
+
+[DriverInstall.nt.AddReg]
+HKR,,DevLoader,,*ntkern
+HKR,,NTMPDriver,,USBSER.sys
+HKR,,EnumPropPages32,,"MsPorts.dll,SerialPortPropPageProvider"
+
+[DriverInstall.nt.Services]
+AddService=usbser, 0x00000002, DriverService.nt
+
+[DriverService.nt]
+DisplayName=%SERVICE%
+ServiceType=1
+StartType=3
+ErrorControl=1
+ServiceBinary=%12%\USBSER.sys
+
+;------------------------------------------------------------------------------
+;  Vista-64bit Sections
+;------------------------------------------------------------------------------
+
+[DriverInstall.NTamd64]
+include=mdmcpq.inf
+CopyFiles=DriverCopyFiles.NTamd64
+AddReg=DriverInstall.NTamd64.AddReg
+
+[DriverCopyFiles.NTamd64]
+USBSER.sys,,,0x20
+
+[DriverInstall.NTamd64.AddReg]
+HKR,,DevLoader,,*ntkern
+HKR,,NTMPDriver,,USBSER.sys
+HKR,,EnumPropPages32,,"MsPorts.dll,SerialPortPropPageProvider"
+
+[DriverInstall.NTamd64.Services]
+AddService=usbser, 0x00000002, DriverService.NTamd64
+
+[DriverService.NTamd64]
+DisplayName=%SERVICE%
+ServiceType=1
+StartType=3
+ErrorControl=1
+ServiceBinary=%12%\USBSER.sys
+
+
+;------------------------------------------------------------------------------
+;  Vendor and Product ID Definitions
+;------------------------------------------------------------------------------
+; When developing your USB device, the VID and PID used in the PC side
+; application program and the firmware on the microcontroller must match.
+; Modify the below line to use your VID and PID.  Use the format as shown
+; below.
+; Note: One INF file can be used for multiple devices with different
+;       VID and PIDs.  For each supported device, append
+;       ",USB\VID_xxxx&PID_yyyy" to the end of the line.
+;------------------------------------------------------------------------------
+[SourceDisksFiles]
+[SourceDisksNames]
+[DeviceList]
+%DESCRIPTION%=DriverInstall, USB\VID_0525&PID_A4A7, USB\VID_1D6B&PID_0104&MI_02, USB\VID_1D6B&PID_0106&MI_00
+
+[DeviceList.NTamd64]
+%DESCRIPTION%=DriverInstall, USB\VID_0525&PID_A4A7, USB\VID_1D6B&PID_0104&MI_02, USB\VID_1D6B&PID_0106&MI_00
+
+
+;------------------------------------------------------------------------------
+;  String Definitions
+;------------------------------------------------------------------------------
+;Modify these strings to customize your device
+;------------------------------------------------------------------------------
+[Strings]
+Linux               = "Linux Developer Community"
+DESCRIPTION         = "Gadget Serial"
+SERVICE             = "USB RS-232 Emulation Driver"