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, 37 insertions, 0 deletions

diff --git a/include/sound/sof/dai-amd.h b/include/sound/sof/dai-amd.h
new file mode 100644
index 000000000..e2107da65
--- /dev/null
+++ b/include/sound/sof/dai-amd.h
@@ -0,0 +1,37 @@
+/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-3-Clause) */
+/*
+ * This file is provided under a dual BSD/GPLv2 license. When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * Copyright(c) 2021 Advanced Micro Devices, Inc.. All rights reserved.
+ */
+
+#ifndef __INCLUDE_SOUND_SOF_DAI_AMD_H__
+#define __INCLUDE_SOUND_SOF_DAI_AMD_H__
+
+#include <sound/sof/header.h>
+
+/* ACP Configuration Request - SOF_IPC_DAI_AMD_CONFIG */
+struct sof_ipc_dai_acp_params {
+	struct sof_ipc_hdr hdr;
+
+	uint32_t fsync_rate;    /* FSYNC frequency in Hz */
+	uint32_t tdm_slots;
+	uint32_t tdm_mode;
+	uint32_t format;
+} __packed;
+
+/* ACPDMIC Configuration Request - SOF_IPC_DAI_AMD_CONFIG */
+struct sof_ipc_dai_acpdmic_params {
+	uint32_t pdm_rate;
+	uint32_t pdm_ch;
+} __packed;
+
+/* ACP_SDW Configuration Request - SOF_IPC_DAI_AMD_SDW_CONFIG */
+struct sof_ipc_dai_acp_sdw_params {
+	struct sof_ipc_hdr hdr;
+	u32 rate;
+	u32 channels;
+} __packed;
+
+#endif