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, 49 insertions, 0 deletions

diff --git a/drivers/pinctrl/starfive/Kconfig b/drivers/pinctrl/starfive/Kconfig
new file mode 100644
index 000000000..a9a7cb101
--- /dev/null
+++ b/drivers/pinctrl/starfive/Kconfig
@@ -0,0 +1,49 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+config PINCTRL_STARFIVE_JH7100
+	tristate "Pinctrl and GPIO driver for the StarFive JH7100 SoC"
+	depends on SOC_STARFIVE || COMPILE_TEST
+	depends on OF
+	select GENERIC_PINCTRL_GROUPS
+	select GENERIC_PINMUX_FUNCTIONS
+	select GENERIC_PINCONF
+	select GPIOLIB
+	select GPIOLIB_IRQCHIP
+	default SOC_STARFIVE
+	help
+	  Say yes here to support pin control on the StarFive JH7100 SoC.
+	  This also provides an interface to the GPIO pins not used by other
+	  peripherals supporting inputs, outputs, configuring pull-up/pull-down
+	  and interrupts on input changes.
+
+config PINCTRL_STARFIVE_JH7110
+	bool
+	select GENERIC_PINCTRL_GROUPS
+	select GENERIC_PINMUX_FUNCTIONS
+	select GENERIC_PINCONF
+	select GPIOLIB
+	select GPIOLIB_IRQCHIP
+
+config PINCTRL_STARFIVE_JH7110_SYS
+	tristate "System pinctrl and GPIO driver for the StarFive JH7110 SoC"
+	depends on SOC_STARFIVE  || COMPILE_TEST
+	depends on OF
+	select PINCTRL_STARFIVE_JH7110
+	default SOC_STARFIVE
+	help
+	  Say yes here to support system pin control on the StarFive JH7110 SoC.
+	  This also provides an interface to the GPIO pins not used by other
+	  peripherals supporting inputs, outputs, configuring pull-up/pull-down
+	  and interrupts on input changes.
+
+config PINCTRL_STARFIVE_JH7110_AON
+	tristate "Always-on pinctrl and GPIO driver for the StarFive JH7110 SoC"
+	depends on SOC_STARFIVE  || COMPILE_TEST
+	depends on OF
+	select PINCTRL_STARFIVE_JH7110
+	default SOC_STARFIVE
+	help
+	  Say yes here to support always-on pin control on the StarFive JH7110 SoC.
+	  This also provides an interface to the GPIO pins not used by other
+	  peripherals supporting inputs, outputs, configuring pull-up/pull-down
+	  and interrupts on input changes.