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, 51 insertions, 0 deletions

diff --git a/drivers/usb/common/Kconfig b/drivers/usb/common/Kconfig
new file mode 100644
index 000000000..b85662243
--- /dev/null
+++ b/drivers/usb/common/Kconfig
@@ -0,0 +1,51 @@
+# SPDX-License-Identifier: GPL-2.0
+
+config USB_COMMON
+	tristate
+
+
+config USB_LED_TRIG
+	bool "USB LED Triggers"
+	depends on LEDS_CLASS && USB_COMMON && LEDS_TRIGGERS
+	help
+	  This option adds LED triggers for USB host and/or gadget activity.
+
+	  Say Y here if you are working on a system with led-class supported
+	  LEDs and you want to use them as activity indicators for USB host or
+	  gadget.
+
+config USB_ULPI_BUS
+	tristate "USB ULPI PHY interface support"
+	select USB_COMMON
+	help
+	  UTMI+ Low Pin Interface (ULPI) is specification for a commonly used
+	  USB 2.0 PHY interface. The ULPI specification defines a standard set
+	  of registers that can be used to detect the vendor and product which
+	  allows ULPI to be handled as a bus. This module is the driver for that
+	  bus.
+
+	  The ULPI interfaces (the buses) are registered by the drivers for USB
+	  controllers which support ULPI register access and have ULPI PHY
+	  attached to them. The ULPI PHY drivers themselves are normal PHY
+	  drivers.
+
+	  ULPI PHYs provide often functions such as ADP sensing/probing (OTG
+	  protocol) and USB charger detection.
+
+	  To compile this driver as a module, choose M here: the module will
+	  be called ulpi.
+
+config USB_CONN_GPIO
+	tristate "USB GPIO Based Connection Detection Driver"
+	depends on GPIOLIB
+	select USB_ROLE_SWITCH
+	select POWER_SUPPLY
+	help
+	  The driver supports USB role switch between host and device via GPIO
+	  based USB cable detection, used typically if an input GPIO is used
+	  to detect USB ID pin, and another input GPIO may be also used to detect
+	  Vbus pin at the same time, it also can be used to enable/disable
+	  device if an input GPIO is only used to detect Vbus pin.
+
+	  To compile the driver as a module, choose M here: the module will
+	  be called usb-conn-gpio.ko