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, 74 insertions, 0 deletions

diff --git a/drivers/clk/starfive/Kconfig b/drivers/clk/starfive/Kconfig
new file mode 100644
index 000000000..bd29358ff
--- /dev/null
+++ b/drivers/clk/starfive/Kconfig
@@ -0,0 +1,74 @@
+# SPDX-License-Identifier: GPL-2.0
+
+config CLK_STARFIVE_JH71X0
+	bool
+
+config CLK_STARFIVE_JH7100
+	bool "StarFive JH7100 clock support"
+	depends on ARCH_STARFIVE || COMPILE_TEST
+	select CLK_STARFIVE_JH71X0
+	default ARCH_STARFIVE
+	help
+	  Say yes here to support the clock controller on the StarFive JH7100
+	  SoC.
+
+config CLK_STARFIVE_JH7100_AUDIO
+	tristate "StarFive JH7100 audio clock support"
+	depends on CLK_STARFIVE_JH7100
+	select CLK_STARFIVE_JH71X0
+	default m if ARCH_STARFIVE
+	help
+	  Say Y or M here to support the audio clocks on the StarFive JH7100
+	  SoC.
+
+config CLK_STARFIVE_JH7110_PLL
+	bool "StarFive JH7110 PLL clock support"
+	depends on ARCH_STARFIVE || COMPILE_TEST
+	default ARCH_STARFIVE
+	help
+	  Say yes here to support the PLL clock controller on the
+	  StarFive JH7110 SoC.
+
+config CLK_STARFIVE_JH7110_SYS
+	bool "StarFive JH7110 system clock support"
+	depends on ARCH_STARFIVE || COMPILE_TEST
+	select AUXILIARY_BUS
+	select CLK_STARFIVE_JH71X0
+	select RESET_STARFIVE_JH7110 if RESET_CONTROLLER
+	select CLK_STARFIVE_JH7110_PLL
+	default ARCH_STARFIVE
+	help
+	  Say yes here to support the system clock controller on the
+	  StarFive JH7110 SoC.
+
+config CLK_STARFIVE_JH7110_AON
+	tristate "StarFive JH7110 always-on clock support"
+	depends on CLK_STARFIVE_JH7110_SYS
+	default m if ARCH_STARFIVE
+	help
+	  Say yes here to support the always-on clock controller on the
+	  StarFive JH7110 SoC.
+
+config CLK_STARFIVE_JH7110_STG
+	tristate "StarFive JH7110 System-Top-Group clock support"
+	depends on CLK_STARFIVE_JH7110_SYS
+	default m if ARCH_STARFIVE
+	help
+	  Say yes here to support the System-Top-Group clock controller
+	  on the StarFive JH7110 SoC.
+
+config CLK_STARFIVE_JH7110_ISP
+	tristate "StarFive JH7110 Image-Signal-Process clock support"
+	depends on CLK_STARFIVE_JH7110_SYS && JH71XX_PMU
+	default m if ARCH_STARFIVE
+	help
+	  Say yes here to support the Image-Signal-Process clock controller
+	  on the StarFive JH7110 SoC.
+
+config CLK_STARFIVE_JH7110_VOUT
+	tristate "StarFive JH7110 Video-Output clock support"
+	depends on CLK_STARFIVE_JH7110_SYS && JH71XX_PMU
+	default m if ARCH_STARFIVE
+	help
+	  Say yes here to support the Video-Output clock controller
+	  on the StarFive JH7110 SoC.