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, 38 insertions, 0 deletions

diff --git a/drivers/pinctrl/realtek/Kconfig b/drivers/pinctrl/realtek/Kconfig
new file mode 100644
index 000000000..a156c4ef5
--- /dev/null
+++ b/drivers/pinctrl/realtek/Kconfig
@@ -0,0 +1,38 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+
+config PINCTRL_RTD
+	tristate "Realtek DHC core pin controller driver"
+	depends on ARCH_REALTEK || (COMPILE_TEST && OF)
+	default ARCH_REALTEK
+	select PINMUX
+	select GENERIC_PINCONF
+	select REGMAP_MMIO
+
+config PINCTRL_RTD1619B
+	tristate "Realtek DHC 1619B pin controller driver"
+	depends on PINCTRL_RTD
+	default ARCH_REALTEK
+
+config PINCTRL_RTD1319D
+	tristate "Realtek DHC 1319D pin controller driver"
+	depends on PINCTRL_RTD
+	default ARCH_REALTEK
+
+config PINCTRL_RTD1315E
+	tristate "Realtek DHC 1315E pin controller driver"
+	depends on PINCTRL_RTD
+	default ARCH_REALTEK
+
+config PINCTRL_RTD1625
+	tristate "Realtek DHC 1625 pin controller driver"
+	depends on PINCTRL_RTD
+	default ARCH_REALTEK
+	help
+	  This driver enables support for the pin controller on the Realtek
+	  RTD1625 SoCs.
+
+	  It implements pin multiplexing for function selection and GPIO enabling.
+	  It also utilizes the generic pin configuration interface to manage
+	  electrical properties for both individual pins and pin groups.
+
+	  Say Y here to enable the pinctrl driver for RTD1625 SoCs
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