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, 59 insertions, 0 deletions

diff --git a/drivers/pinctrl/sprd/pinctrl-sprd.h b/drivers/pinctrl/sprd/pinctrl-sprd.h
new file mode 100644
index 000000000..190bcdb3b
--- /dev/null
+++ b/drivers/pinctrl/sprd/pinctrl-sprd.h
@@ -0,0 +1,59 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Driver header file for pin controller driver
+ * Copyright (C) 2017 Spreadtrum  - http://www.spreadtrum.com
+ */
+
+#ifndef __PINCTRL_SPRD_H__
+#define __PINCTRL_SPRD_H__
+
+struct platform_device;
+
+#define NUM_OFFSET	(20)
+#define TYPE_OFFSET	(16)
+#define BIT_OFFSET	(8)
+#define WIDTH_OFFSET	(4)
+
+#define SPRD_PIN_INFO(num, type, offset, width, reg)	\
+		(((num) & 0xFFF) << NUM_OFFSET |	\
+		 ((type) & 0xF) << TYPE_OFFSET |	\
+		 ((offset) & 0xFF) << BIT_OFFSET |	\
+		 ((width) & 0xF) << WIDTH_OFFSET |	\
+		 ((reg) & 0xF))
+
+#define SPRD_PINCTRL_PIN(pin)	SPRD_PINCTRL_PIN_DATA(pin, #pin)
+
+#define SPRD_PINCTRL_PIN_DATA(a, b)				\
+	{							\
+		.name = b,					\
+		.num = (((a) >> NUM_OFFSET) & 0xfff),		\
+		.type = (((a) >> TYPE_OFFSET) & 0xf),		\
+		.bit_offset = (((a) >> BIT_OFFSET) & 0xff),	\
+		.bit_width = ((a) >> WIDTH_OFFSET & 0xf),	\
+		.reg = ((a) & 0xf)				\
+	}
+
+enum pin_type {
+	GLOBAL_CTRL_PIN,
+	COMMON_PIN,
+	MISC_PIN,
+};
+
+struct sprd_pins_info {
+	const char *name;
+	unsigned int num;
+	enum pin_type type;
+
+	/* for global control pins configuration */
+	unsigned long bit_offset;
+	unsigned long bit_width;
+	unsigned int reg;
+};
+
+int sprd_pinctrl_core_probe(struct platform_device *pdev,
+			    struct sprd_pins_info *sprd_soc_pin_info,
+			    int pins_cnt);
+void sprd_pinctrl_remove(struct platform_device *pdev);
+void sprd_pinctrl_shutdown(struct platform_device *pdev);
+
+#endif /* __PINCTRL_SPRD_H__ */