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>

5 files changed, 413 insertions, 0 deletions

diff --git a/arch/microblaze/boot/.gitignore b/arch/microblaze/boot/.gitignore
new file mode 100644
index 000000000..11a9e229f
--- /dev/null
+++ b/arch/microblaze/boot/.gitignore
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0-only
+linux.bin*
+simpleImage.*
diff --git a/arch/microblaze/boot/Makefile b/arch/microblaze/boot/Makefile
new file mode 100644
index 000000000..2b42c370d
--- /dev/null
+++ b/arch/microblaze/boot/Makefile
@@ -0,0 +1,35 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# arch/microblaze/boot/Makefile
+#
+
+targets := linux.bin linux.bin.gz linux.bin.ub simpleImage.*
+
+OBJCOPYFLAGS := -R .note -R .comment -R .note.gnu.build-id -O binary
+
+$(obj)/linux.bin: vmlinux FORCE
+	$(call if_changed,objcopy)
+
+$(obj)/linux.bin.ub: $(obj)/linux.bin FORCE
+	$(call if_changed,uimage)
+
+$(obj)/linux.bin.gz: $(obj)/linux.bin FORCE
+	$(call if_changed,gzip)
+
+quiet_cmd_strip = STRIP   $< $@$2
+	cmd_strip = $(STRIP) -K microblaze_start -K _end -K __log_buf \
+				-K _fdt_start $< -o $@$2
+
+UIMAGE_LOADADDR = $(CONFIG_KERNEL_BASE_ADDR)
+
+$(obj)/simpleImage.$(DTB): vmlinux FORCE
+	$(call if_changed,objcopy)
+
+$(obj)/simpleImage.$(DTB).ub: $(obj)/simpleImage.$(DTB) FORCE
+	$(call if_changed,uimage)
+
+$(obj)/simpleImage.$(DTB).unstrip: vmlinux FORCE
+	$(call if_changed,copy)
+
+$(obj)/simpleImage.$(DTB).strip: vmlinux FORCE
+	$(call if_changed,strip)
diff --git a/arch/microblaze/boot/dts/Makefile b/arch/microblaze/boot/dts/Makefile
new file mode 100644
index 000000000..b84e2cbb2
--- /dev/null
+++ b/arch/microblaze/boot/dts/Makefile
@@ -0,0 +1,20 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+
+dtb-y := system.dtb
+
+ifneq ($(DTB),)
+obj-y += linked_dtb.o
+
+# Ensure system.dtb exists
+$(obj)/linked_dtb.o: $(obj)/system.dtb
+
+# Generate system.dtb from $(DTB).dtb
+ifneq ($(DTB),system)
+$(obj)/system.dtb: $(obj)/$(DTB).dtb
+	$(call if_changed,copy)
+endif
+endif
+
+# Rule to build device tree blobs
+DTC_FLAGS := -p 1024
diff --git a/arch/microblaze/boot/dts/linked_dtb.S b/arch/microblaze/boot/dts/linked_dtb.S
new file mode 100644
index 000000000..23345af37
--- /dev/null
+++ b/arch/microblaze/boot/dts/linked_dtb.S
@@ -0,0 +1,2 @@
+.section __fdt_blob,"a"
+.incbin "arch/microblaze/boot/dts/system.dtb"
diff --git a/arch/microblaze/boot/dts/system.dts b/arch/microblaze/boot/dts/system.dts
new file mode 100644
index 000000000..22252451e
--- /dev/null
+++ b/arch/microblaze/boot/dts/system.dts
@@ -0,0 +1,353 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Device Tree Generator version: 1.1
+ *
+ * (C) Copyright 2007-2008 Xilinx, Inc.
+ * (C) Copyright 2007-2009 Michal Simek
+ *
+ * Michal SIMEK <monstr@monstr.eu>
+ *
+ * CAUTION: This file is automatically generated by libgen.
+ * Version: Xilinx EDK 10.1.03 EDK_K_SP3.6
+ *
+ * XPS project directory: Xilinx-ML505-ll_temac-sgdma-MMU-FDT-edk101
+ */
+
+/dts-v1/;
+/ {
+	#address-cells = <1>;
+	#size-cells = <1>;
+	compatible = "xlnx,microblaze";
+	model = "testing";
+	DDR2_SDRAM: memory@90000000 {
+		device_type = "memory";
+		reg = < 0x90000000 0x10000000 >;
+	} ;
+	aliases {
+		ethernet0 = &Hard_Ethernet_MAC;
+		serial0 = &RS232_Uart_1;
+	} ;
+	chosen {
+		bootargs = "console=ttyUL0,115200 highres=on";
+		stdout-path = "/plb@0/serial@84000000";
+	} ;
+	cpus {
+		#address-cells = <1>;
+		#cpus = <0x1>;
+		#size-cells = <0>;
+		microblaze_0: cpu@0 {
+			clock-frequency = <125000000>;
+			compatible = "xlnx,microblaze-7.10.d";
+			d-cache-baseaddr = <0x90000000>;
+			d-cache-highaddr = <0x9fffffff>;
+			d-cache-line-size = <0x10>;
+			d-cache-size = <0x2000>;
+			device_type = "cpu";
+			i-cache-baseaddr = <0x90000000>;
+			i-cache-highaddr = <0x9fffffff>;
+			i-cache-line-size = <0x10>;
+			i-cache-size = <0x2000>;
+			model = "microblaze,7.10.d";
+			reg = <0>;
+			timebase-frequency = <125000000>;
+			xlnx,addr-tag-bits = <0xf>;
+			xlnx,allow-dcache-wr = <0x1>;
+			xlnx,allow-icache-wr = <0x1>;
+			xlnx,area-optimized = <0x0>;
+			xlnx,cache-byte-size = <0x2000>;
+			xlnx,d-lmb = <0x1>;
+			xlnx,d-opb = <0x0>;
+			xlnx,d-plb = <0x1>;
+			xlnx,data-size = <0x20>;
+			xlnx,dcache-addr-tag = <0xf>;
+			xlnx,dcache-always-used = <0x1>;
+			xlnx,dcache-byte-size = <0x2000>;
+			xlnx,dcache-line-len = <0x4>;
+			xlnx,dcache-use-fsl = <0x1>;
+			xlnx,debug-enabled = <0x1>;
+			xlnx,div-zero-exception = <0x1>;
+			xlnx,dopb-bus-exception = <0x0>;
+			xlnx,dynamic-bus-sizing = <0x1>;
+			xlnx,edge-is-positive = <0x1>;
+			xlnx,family = "virtex5";
+			xlnx,endianness = <0x1>;
+			xlnx,fpu-exception = <0x1>;
+			xlnx,fsl-data-size = <0x20>;
+			xlnx,fsl-exception = <0x0>;
+			xlnx,fsl-links = <0x0>;
+			xlnx,i-lmb = <0x1>;
+			xlnx,i-opb = <0x0>;
+			xlnx,i-plb = <0x1>;
+			xlnx,icache-always-used = <0x1>;
+			xlnx,icache-line-len = <0x4>;
+			xlnx,icache-use-fsl = <0x1>;
+			xlnx,ill-opcode-exception = <0x1>;
+			xlnx,instance = "microblaze_0";
+			xlnx,interconnect = <0x1>;
+			xlnx,interrupt-is-edge = <0x0>;
+			xlnx,iopb-bus-exception = <0x0>;
+			xlnx,mmu-dtlb-size = <0x4>;
+			xlnx,mmu-itlb-size = <0x2>;
+			xlnx,mmu-tlb-access = <0x3>;
+			xlnx,mmu-zones = <0x10>;
+			xlnx,number-of-pc-brk = <0x1>;
+			xlnx,number-of-rd-addr-brk = <0x0>;
+			xlnx,number-of-wr-addr-brk = <0x0>;
+			xlnx,opcode-0x0-illegal = <0x1>;
+			xlnx,pvr = <0x2>;
+			xlnx,pvr-user1 = <0x0>;
+			xlnx,pvr-user2 = <0x0>;
+			xlnx,reset-msr = <0x0>;
+			xlnx,sco = <0x0>;
+			xlnx,unaligned-exceptions = <0x1>;
+			xlnx,use-barrel = <0x1>;
+			xlnx,use-dcache = <0x1>;
+			xlnx,use-div = <0x1>;
+			xlnx,use-ext-brk = <0x1>;
+			xlnx,use-ext-nm-brk = <0x1>;
+			xlnx,use-extended-fsl-instr = <0x0>;
+			xlnx,use-fpu = <0x2>;
+			xlnx,use-hw-mul = <0x2>;
+			xlnx,use-icache = <0x1>;
+			xlnx,use-interrupt = <0x1>;
+			xlnx,use-mmu = <0x3>;
+			xlnx,use-msr-instr = <0x1>;
+			xlnx,use-pcmp-instr = <0x1>;
+		} ;
+	} ;
+	mb_plb: plb@0 {
+		#address-cells = <1>;
+		#size-cells = <1>;
+		compatible = "xlnx,plb-v46-1.03.a", "xlnx,plb-v46-1.00.a", "simple-bus";
+		ranges ;
+		FLASH: flash@a0000000 {
+			bank-width = <2>;
+			compatible = "xlnx,xps-mch-emc-2.00.a", "cfi-flash";
+			reg = < 0xa0000000 0x2000000 >;
+			xlnx,family = "virtex5";
+			xlnx,include-datawidth-matching-0 = <0x1>;
+			xlnx,include-datawidth-matching-1 = <0x0>;
+			xlnx,include-datawidth-matching-2 = <0x0>;
+			xlnx,include-datawidth-matching-3 = <0x0>;
+			xlnx,include-negedge-ioregs = <0x0>;
+			xlnx,include-plb-ipif = <0x1>;
+			xlnx,include-wrbuf = <0x1>;
+			xlnx,max-mem-width = <0x10>;
+			xlnx,mch-native-dwidth = <0x20>;
+			xlnx,mch-plb-clk-period-ps = <0x1f40>;
+			xlnx,mch-splb-awidth = <0x20>;
+			xlnx,mch0-accessbuf-depth = <0x10>;
+			xlnx,mch0-protocol = <0x0>;
+			xlnx,mch0-rddatabuf-depth = <0x10>;
+			xlnx,mch1-accessbuf-depth = <0x10>;
+			xlnx,mch1-protocol = <0x0>;
+			xlnx,mch1-rddatabuf-depth = <0x10>;
+			xlnx,mch2-accessbuf-depth = <0x10>;
+			xlnx,mch2-protocol = <0x0>;
+			xlnx,mch2-rddatabuf-depth = <0x10>;
+			xlnx,mch3-accessbuf-depth = <0x10>;
+			xlnx,mch3-protocol = <0x0>;
+			xlnx,mch3-rddatabuf-depth = <0x10>;
+			xlnx,mem0-width = <0x10>;
+			xlnx,mem1-width = <0x20>;
+			xlnx,mem2-width = <0x20>;
+			xlnx,mem3-width = <0x20>;
+			xlnx,num-banks-mem = <0x1>;
+			xlnx,num-channels = <0x0>;
+			xlnx,priority-mode = <0x0>;
+			xlnx,synch-mem-0 = <0x0>;
+			xlnx,synch-mem-1 = <0x0>;
+			xlnx,synch-mem-2 = <0x0>;
+			xlnx,synch-mem-3 = <0x0>;
+			xlnx,synch-pipedelay-0 = <0x2>;
+			xlnx,synch-pipedelay-1 = <0x2>;
+			xlnx,synch-pipedelay-2 = <0x2>;
+			xlnx,synch-pipedelay-3 = <0x2>;
+			xlnx,tavdv-ps-mem-0 = <0x1adb0>;
+			xlnx,tavdv-ps-mem-1 = <0x3a98>;
+			xlnx,tavdv-ps-mem-2 = <0x3a98>;
+			xlnx,tavdv-ps-mem-3 = <0x3a98>;
+			xlnx,tcedv-ps-mem-0 = <0x1adb0>;
+			xlnx,tcedv-ps-mem-1 = <0x3a98>;
+			xlnx,tcedv-ps-mem-2 = <0x3a98>;
+			xlnx,tcedv-ps-mem-3 = <0x3a98>;
+			xlnx,thzce-ps-mem-0 = <0x88b8>;
+			xlnx,thzce-ps-mem-1 = <0x1b58>;
+			xlnx,thzce-ps-mem-2 = <0x1b58>;
+			xlnx,thzce-ps-mem-3 = <0x1b58>;
+			xlnx,thzoe-ps-mem-0 = <0x1b58>;
+			xlnx,thzoe-ps-mem-1 = <0x1b58>;
+			xlnx,thzoe-ps-mem-2 = <0x1b58>;
+			xlnx,thzoe-ps-mem-3 = <0x1b58>;
+			xlnx,tlzwe-ps-mem-0 = <0x88b8>;
+			xlnx,tlzwe-ps-mem-1 = <0x0>;
+			xlnx,tlzwe-ps-mem-2 = <0x0>;
+			xlnx,tlzwe-ps-mem-3 = <0x0>;
+			xlnx,twc-ps-mem-0 = <0x2af8>;
+			xlnx,twc-ps-mem-1 = <0x3a98>;
+			xlnx,twc-ps-mem-2 = <0x3a98>;
+			xlnx,twc-ps-mem-3 = <0x3a98>;
+			xlnx,twp-ps-mem-0 = <0x11170>;
+			xlnx,twp-ps-mem-1 = <0x2ee0>;
+			xlnx,twp-ps-mem-2 = <0x2ee0>;
+			xlnx,twp-ps-mem-3 = <0x2ee0>;
+			xlnx,xcl0-linesize = <0x4>;
+			xlnx,xcl0-writexfer = <0x1>;
+			xlnx,xcl1-linesize = <0x4>;
+			xlnx,xcl1-writexfer = <0x1>;
+			xlnx,xcl2-linesize = <0x4>;
+			xlnx,xcl2-writexfer = <0x1>;
+			xlnx,xcl3-linesize = <0x4>;
+			xlnx,xcl3-writexfer = <0x1>;
+		} ;
+		Hard_Ethernet_MAC: xps-ll-temac@81c00000 {
+			#address-cells = <1>;
+			#size-cells = <1>;
+			compatible = "xlnx,compound";
+			ranges ;
+			ethernet@81c00000 {
+				compatible = "xlnx,xps-ll-temac-1.01.b", "xlnx,xps-ll-temac-1.00.a";
+				interrupt-parent = <&xps_intc_0>;
+				interrupts = < 5 2 >;
+				llink-connected = <&PIM3>;
+				local-mac-address = [ 00 0a 35 00 00 00 ];
+				reg = < 0x81c00000 0x40 >;
+				xlnx,bus2core-clk-ratio = <0x1>;
+				xlnx,phy-type = <0x1>;
+				xlnx,phyaddr = <0x1>;
+				xlnx,rxcsum = <0x0>;
+				xlnx,rxfifo = <0x1000>;
+				xlnx,temac-type = <0x0>;
+				xlnx,txcsum = <0x0>;
+				xlnx,txfifo = <0x1000>;
+			} ;
+		} ;
+		IIC_EEPROM: i2c@81600000 {
+			compatible = "xlnx,xps-iic-2.00.a";
+			interrupt-parent = <&xps_intc_0>;
+			interrupts = < 6 2 >;
+			reg = < 0x81600000 0x10000 >;
+			xlnx,clk-freq = <0x7735940>;
+			xlnx,family = "virtex5";
+			xlnx,gpo-width = <0x1>;
+			xlnx,iic-freq = <0x186a0>;
+			xlnx,scl-inertial-delay = <0x0>;
+			xlnx,sda-inertial-delay = <0x0>;
+			xlnx,ten-bit-adr = <0x0>;
+		} ;
+		LEDs_8Bit: gpio@81400000 {
+			compatible = "xlnx,xps-gpio-1.00.a";
+			interrupt-parent = <&xps_intc_0>;
+			interrupts = < 7 2 >;
+			reg = < 0x81400000 0x10000 >;
+			xlnx,all-inputs = <0x0>;
+			xlnx,all-inputs-2 = <0x0>;
+			xlnx,dout-default = <0x0>;
+			xlnx,dout-default-2 = <0x0>;
+			xlnx,family = "virtex5";
+			xlnx,gpio-width = <0x8>;
+			xlnx,interrupt-present = <0x1>;
+			xlnx,is-bidir = <0x1>;
+			xlnx,is-bidir-2 = <0x1>;
+			xlnx,is-dual = <0x0>;
+			xlnx,tri-default = <0xffffffff>;
+			xlnx,tri-default-2 = <0xffffffff>;
+			#gpio-cells = <2>;
+			gpio-controller;
+		} ;
+
+		gpio-leds {
+			compatible = "gpio-leds";
+
+			heartbeat {
+				label = "Heartbeat";
+				gpios = <&LEDs_8Bit 4 1>;
+				linux,default-trigger = "heartbeat";
+			};
+
+			yellow {
+				label = "Yellow";
+				gpios = <&LEDs_8Bit 5 1>;
+			};
+
+			red {
+				label = "Red";
+				gpios = <&LEDs_8Bit 6 1>;
+			};
+
+			green {
+				label = "Green";
+				gpios = <&LEDs_8Bit 7 1>;
+			};
+		} ;
+
+		gpio-restart {
+			compatible = "gpio-restart";
+			/*
+			 * FIXME: is this active low or active high?
+			 * the current flag (1) indicates active low.
+			 * delay measures are templates, should be adjusted
+			 * to datasheet or trial-and-error with real hardware.
+			 */
+			gpios = <&LEDs_8Bit 2 1>;
+			active-delay = <100>;
+			inactive-delay = <10>;
+			wait-delay = <100>;
+		};
+
+		RS232_Uart_1: serial@84000000 {
+			clock-frequency = <125000000>;
+			compatible = "xlnx,xps-uartlite-1.00.a";
+			current-speed = <115200>;
+			device_type = "serial";
+			interrupt-parent = <&xps_intc_0>;
+			interrupts = < 8 0 >;
+			port-number = <0>;
+			reg = < 0x84000000 0x10000 >;
+			xlnx,baudrate = <0x1c200>;
+			xlnx,data-bits = <0x8>;
+			xlnx,family = "virtex5";
+			xlnx,odd-parity = <0x0>;
+			xlnx,use-parity = <0x0>;
+		} ;
+		debug_module: debug@84400000 {
+			compatible = "xlnx,mdm-1.00.d";
+			reg = < 0x84400000 0x10000 >;
+			xlnx,family = "virtex5";
+			xlnx,interconnect = <0x1>;
+			xlnx,jtag-chain = <0x2>;
+			xlnx,mb-dbg-ports = <0x1>;
+			xlnx,uart-width = <0x8>;
+			xlnx,use-uart = <0x1>;
+			xlnx,write-fsl-ports = <0x0>;
+		} ;
+		mpmc@90000000 {
+			#address-cells = <1>;
+			#size-cells = <1>;
+			compatible = "xlnx,mpmc-4.02.a";
+			ranges ;
+			PIM3: sdma@84600180 {
+				compatible = "xlnx,ll-dma-1.00.a";
+				interrupt-parent = <&xps_intc_0>;
+				interrupts = < 2 2 1 2 >;
+				reg = < 0x84600180 0x80 >;
+			} ;
+		} ;
+		xps_intc_0: interrupt-controller@81800000 {
+			#interrupt-cells = <0x2>;
+			compatible = "xlnx,xps-intc-1.00.a";
+			interrupt-controller ;
+			reg = < 0x81800000 0x10000 >;
+			xlnx,kind-of-intr = <0x100>;
+			xlnx,num-intr-inputs = <0x9>;
+		} ;
+		xps_timer_1: timer@83c00000 {
+			compatible = "xlnx,xps-timer-1.00.a";
+			interrupt-parent = <&xps_intc_0>;
+			interrupts = < 3 2 >;
+			reg = < 0x83c00000 0x10000 >;
+			xlnx,count-width = <0x20>;
+			xlnx,one-timer-only = <0x0>;
+		} ;
+	} ;
+}  ;