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, 117 insertions, 0 deletions

diff --git a/drivers/bluetooth/btbcm.h b/drivers/bluetooth/btbcm.h
new file mode 100644
index 000000000..b4cb24231
--- /dev/null
+++ b/drivers/bluetooth/btbcm.h
@@ -0,0 +1,117 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *
+ *  Bluetooth support for Broadcom devices
+ *
+ *  Copyright (C) 2015  Intel Corporation
+ */
+
+#define BCM_UART_CLOCK_48MHZ	0x01
+#define BCM_UART_CLOCK_24MHZ	0x02
+
+struct bcm_update_uart_baud_rate {
+	__le16 zero;
+	__le32 baud_rate;
+} __packed;
+
+struct bcm_write_uart_clock_setting {
+	__u8 type;
+} __packed;
+
+struct bcm_set_sleep_mode {
+	__u8 sleep_mode;
+	__u8 idle_host;
+	__u8 idle_dev;
+	__u8 bt_wake_active;
+	__u8 host_wake_active;
+	__u8 allow_host_sleep;
+	__u8 combine_modes;
+	__u8 tristate_control;
+	__u8 usb_auto_sleep;
+	__u8 usb_resume_timeout;
+	__u8 break_to_host;
+	__u8 pulsed_host_wake;
+} __packed;
+
+struct bcm_set_pcm_int_params {
+	__u8 routing;
+	__u8 rate;
+	__u8 frame_sync;
+	__u8 sync_mode;
+	__u8 clock_mode;
+} __packed;
+
+struct bcm_set_pcm_format_params {
+	__u8 lsb_first;
+	__u8 fill_value;
+	__u8 fill_method;
+	__u8 fill_num;
+	__u8 right_justify;
+} __packed;
+
+#if IS_ENABLED(CONFIG_BT_BCM)
+
+int btbcm_check_bdaddr(struct hci_dev *hdev);
+int btbcm_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr);
+int btbcm_patchram(struct hci_dev *hdev, const struct firmware *fw);
+int btbcm_read_pcm_int_params(struct hci_dev *hdev,
+			      struct bcm_set_pcm_int_params *params);
+int btbcm_write_pcm_int_params(struct hci_dev *hdev,
+			       const struct bcm_set_pcm_int_params *params);
+
+int btbcm_setup_patchram(struct hci_dev *hdev);
+int btbcm_setup_apple(struct hci_dev *hdev);
+
+int btbcm_initialize(struct hci_dev *hdev, bool *fw_load_done, bool use_autobaud_mode);
+int btbcm_finalize(struct hci_dev *hdev, bool *fw_load_done, bool use_autobaud_mode);
+
+#else
+
+static inline int btbcm_check_bdaddr(struct hci_dev *hdev)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int btbcm_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int btbcm_read_pcm_int_params(struct hci_dev *hdev,
+			      struct bcm_set_pcm_int_params *params)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int btbcm_write_pcm_int_params(struct hci_dev *hdev,
+			       const struct bcm_set_pcm_int_params *params)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int btbcm_patchram(struct hci_dev *hdev, const struct firmware *fw)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int btbcm_setup_patchram(struct hci_dev *hdev)
+{
+	return 0;
+}
+
+static inline int btbcm_setup_apple(struct hci_dev *hdev)
+{
+	return 0;
+}
+
+static inline int btbcm_initialize(struct hci_dev *hdev, bool *fw_load_done, bool use_autobaud_mode)
+{
+	return 0;
+}
+
+static inline int btbcm_finalize(struct hci_dev *hdev, bool *fw_load_done, bool use_autobaud_mode)
+{
+	return 0;
+}
+
+#endif