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, 57 insertions, 0 deletions

diff --git a/drivers/pinctrl/spear/Kconfig b/drivers/pinctrl/spear/Kconfig
new file mode 100644
index 000000000..98f5a84cc
--- /dev/null
+++ b/drivers/pinctrl/spear/Kconfig
@@ -0,0 +1,57 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# ST Microelectronics SPEAr PINCTRL drivers
+#
+
+if PLAT_SPEAR
+
+config PINCTRL_SPEAR
+	bool
+	depends on OF
+	select PINMUX
+	help
+	  This enables pin control drivers for SPEAr Platform
+
+config PINCTRL_SPEAR3XX
+	bool
+	depends on ARCH_SPEAR3XX
+	select PINCTRL_SPEAR
+
+config PINCTRL_SPEAR300
+	bool "ST Microelectronics SPEAr300 SoC pin controller driver"
+	depends on MACH_SPEAR300
+	select PINCTRL_SPEAR3XX
+
+config PINCTRL_SPEAR310
+	bool "ST Microelectronics SPEAr310 SoC pin controller driver"
+	depends on MACH_SPEAR310
+	select PINCTRL_SPEAR3XX
+	select PINCTRL_SPEAR_PLGPIO
+
+config PINCTRL_SPEAR320
+	bool "ST Microelectronics SPEAr320 SoC pin controller driver"
+	depends on MACH_SPEAR320
+	select PINCTRL_SPEAR3XX
+	select PINCTRL_SPEAR_PLGPIO
+
+config PINCTRL_SPEAR1310
+	bool "ST Microelectronics SPEAr1310 SoC pin controller driver"
+	depends on MACH_SPEAR1310
+	select PINCTRL_SPEAR
+	select PINCTRL_SPEAR_PLGPIO
+
+config PINCTRL_SPEAR1340
+	bool "ST Microelectronics SPEAr1340 SoC pin controller driver"
+	depends on MACH_SPEAR1340
+	select PINCTRL_SPEAR
+	select PINCTRL_SPEAR_PLGPIO
+
+config PINCTRL_SPEAR_PLGPIO
+	bool "SPEAr SoC PLGPIO Controller"
+	depends on GPIOLIB && PINCTRL_SPEAR
+	select GPIOLIB_IRQCHIP
+	help
+	  Say yes here to support PLGPIO controller on ST Microelectronics SPEAr
+	  SoCs.
+
+endif