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, 60 insertions, 0 deletions

diff --git a/drivers/phy/st/Kconfig b/drivers/phy/st/Kconfig
new file mode 100644
index 000000000..49206185e
--- /dev/null
+++ b/drivers/phy/st/Kconfig
@@ -0,0 +1,60 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Phy drivers for STMicro platforms
+#
+config PHY_MIPHY28LP
+	tristate "STMicroelectronics MIPHY28LP PHY driver for STiH407"
+	depends on ARCH_STI || COMPILE_TEST
+	select GENERIC_PHY
+	help
+	  Enable this to support the miphy transceiver (for SATA/PCIE/USB3)
+	  that is part of STMicroelectronics STiH407 SoC.
+
+config PHY_ST_SPEAR1310_MIPHY
+	tristate "ST SPEAR1310-MIPHY driver"
+	select GENERIC_PHY
+	depends on MACH_SPEAR1310 || COMPILE_TEST
+	help
+	  Support for ST SPEAr1310 MIPHY which can be used for PCIe and SATA.
+
+config PHY_ST_SPEAR1340_MIPHY
+	tristate "ST SPEAR1340-MIPHY driver"
+	select GENERIC_PHY
+	depends on MACH_SPEAR1340 || COMPILE_TEST
+	help
+	  Support for ST SPEAr1340 MIPHY which can be used for PCIe and SATA.
+
+config PHY_STIH407_USB
+	tristate "STMicroelectronics USB2 picoPHY driver for STiH407 family"
+	depends on RESET_CONTROLLER
+	depends on ARCH_STI || COMPILE_TEST
+	select GENERIC_PHY
+	help
+	  Enable this support to enable the picoPHY device used by USB2
+	  and USB3 controllers on STMicroelectronics STiH407 SoC families.
+
+config PHY_STM32_COMBOPHY
+	tristate "STMicroelectronics COMBOPHY driver for STM32MP25"
+	depends on ARCH_STM32 || COMPILE_TEST
+	select GENERIC_PHY
+	help
+	  Enable this to support the COMBOPHY device used by USB3 or PCIe
+	  controllers on STMicroelectronics STM32MP25 SoC.
+	  This driver controls the COMBOPHY block to generate the PCIe 100Mhz
+	  reference clock from either the external clock generator or HSE
+	  internal SoC clock source.
+
+config PHY_STM32_USBPHYC
+	tristate "STMicroelectronics STM32 USB HS PHY Controller driver"
+	depends on ARCH_STM32 || COMPILE_TEST
+	depends on COMMON_CLK
+	select GENERIC_PHY
+	help
+	  Enable this to support the High-Speed USB transceivers that are part
+	  of some STMicroelectronics STM32 SoCs.
+
+	  This driver controls the entire USB PHY block: the USB PHY controller
+	  (USBPHYC) and the two 8-bit wide UTMI+ interfaces. First interface is
+	  used by an HS USB Host controller, and the second one is shared
+	  between an HS USB OTG controller and an HS USB Host controller,
+	  selected by a USB switch.