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, 111 insertions, 0 deletions

diff --git a/drivers/clk/bcm/Kconfig b/drivers/clk/bcm/Kconfig
new file mode 100644
index 000000000..a972d763e
--- /dev/null
+++ b/drivers/clk/bcm/Kconfig
@@ -0,0 +1,111 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+config CLK_BCM2711_DVP
+	tristate "Broadcom BCM2711 DVP support"
+	depends on ARCH_BCM2835 ||COMPILE_TEST
+	depends on COMMON_CLK
+	default ARCH_BCM2835
+	select RESET_CONTROLLER
+	select RESET_SIMPLE
+	help
+	  Enable common clock framework support for the Broadcom BCM2711
+	  DVP Controller.
+
+config CLK_BCM2835
+	bool "Broadcom BCM2835 clock support"
+	depends on ARCH_BCM2835 || ARCH_BRCMSTB || COMPILE_TEST
+	depends on COMMON_CLK
+	default ARCH_BCM2835 || ARCH_BRCMSTB
+	help
+	  Enable common clock framework support for Broadcom BCM2835
+	  SoCs.
+
+config CLK_BCM_63XX
+	bool "Broadcom BCM63xx clock support"
+	depends on ARCH_BCMBCA || COMPILE_TEST
+	select COMMON_CLK_IPROC
+	default ARCH_BCMBCA
+	help
+	  Enable common clock framework support for Broadcom BCM63xx DSL SoCs
+	  based on the ARM architecture
+
+config CLK_BCM_63XX_GATE
+	bool "Broadcom BCM63xx gated clock support"
+	depends on BMIPS_GENERIC || COMPILE_TEST
+	default BMIPS_GENERIC
+	help
+	  Enable common clock framework support for Broadcom BCM63xx DSL SoCs
+	  based on the MIPS architecture
+
+config CLK_BCM63268_TIMER
+	bool "Broadcom BCM63268 timer clock and reset support"
+	depends on BMIPS_GENERIC || COMPILE_TEST
+	default BMIPS_GENERIC
+	select RESET_CONTROLLER
+	help
+	  Enable timer clock and reset support for Broadcom BCM63268 DSL SoCs
+	  based on the MIPS architecture.
+
+config CLK_BCM_KONA
+	bool "Broadcom Kona CCU clock support"
+	depends on ARCH_BCM_MOBILE || COMPILE_TEST
+	default ARCH_BCM_MOBILE
+	help
+	  Enable common clock framework support for Broadcom SoCs
+	  using "Kona" style clock control units, including those
+	  in the BCM281xx and BCM21664 families.
+
+config COMMON_CLK_IPROC
+	bool
+	help
+	  Enable common clock framework support for Broadcom SoCs
+	  based on the iProc architecture
+
+config CLK_BCM_CYGNUS
+	bool "Broadcom Cygnus clock support"
+	depends on ARCH_BCM_CYGNUS || COMPILE_TEST
+	select COMMON_CLK_IPROC
+	default ARCH_BCM_CYGNUS
+	help
+	  Enable common clock framework support for the Broadcom Cygnus SoC
+
+config CLK_BCM_HR2
+	bool "Broadcom Hurricane 2 clock support"
+	depends on ARCH_BCM_HR2 || COMPILE_TEST
+	select COMMON_CLK_IPROC
+	default ARCH_BCM_HR2
+	help
+	  Enable common clock framework support for the Broadcom Hurricane 2
+	  SoC
+
+config CLK_BCM_NSP
+	bool "Broadcom Northstar/Northstar Plus clock support"
+	depends on ARCH_BCM_5301X || ARCH_BCM_NSP || COMPILE_TEST
+	select COMMON_CLK_IPROC
+	default ARCH_BCM_5301X || ARCH_BCM_NSP
+	help
+	  Enable common clock framework support for the Broadcom Northstar and
+	  Northstar Plus SoCs
+
+config CLK_BCM_NS2
+	bool "Broadcom Northstar 2 clock support"
+	depends on ARCH_BCM_IPROC || COMPILE_TEST
+	select COMMON_CLK_IPROC
+	default ARCH_BCM_IPROC
+	help
+	  Enable common clock framework support for the Broadcom Northstar 2 SoC
+
+config CLK_BCM_SR
+	bool "Broadcom Stingray clock support"
+	depends on ARCH_BCM_IPROC || COMPILE_TEST
+	select COMMON_CLK_IPROC
+	default ARCH_BCM_IPROC
+	help
+	  Enable common clock framework support for the Broadcom Stingray SoC
+
+config CLK_RASPBERRYPI
+	tristate "Raspberry Pi firmware based clock support"
+	depends on RASPBERRYPI_FIRMWARE || (COMPILE_TEST && !RASPBERRYPI_FIRMWARE)
+	help
+	  Enable common clock framework support for Raspberry Pi's firmware
+	  dependent clocks