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, 107 insertions, 0 deletions

diff --git a/include/sound/sof/trace.h b/include/sound/sof/trace.h
new file mode 100644
index 000000000..ac2ebb6fb
--- /dev/null
+++ b/include/sound/sof/trace.h
@@ -0,0 +1,107 @@
+/* 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) 2018 Intel Corporation
+ */
+
+#ifndef __INCLUDE_SOUND_SOF_TRACE_H__
+#define __INCLUDE_SOUND_SOF_TRACE_H__
+
+#include <sound/sof/header.h>
+#include <sound/sof/stream.h>
+
+/*
+ * DMA for Trace
+ */
+
+#define SOF_TRACE_FILENAME_SIZE		32
+
+/* DMA for Trace params info - SOF_IPC_DEBUG_DMA_PARAMS */
+/* Deprecated - use sof_ipc_dma_trace_params_ext */
+struct sof_ipc_dma_trace_params {
+	struct sof_ipc_cmd_hdr hdr;
+	struct sof_ipc_host_buffer buffer;
+	uint32_t stream_tag;
+}  __packed;
+
+/* DMA for Trace params info - SOF_IPC_DEBUG_DMA_PARAMS_EXT */
+struct sof_ipc_dma_trace_params_ext {
+	struct sof_ipc_cmd_hdr hdr;
+	struct sof_ipc_host_buffer buffer;
+	uint32_t stream_tag;
+	uint64_t timestamp_ns; /* in nanosecond */
+	uint32_t reserved[8];
+}  __packed;
+
+/* DMA for Trace params info - SOF_IPC_DEBUG_DMA_PARAMS */
+struct sof_ipc_dma_trace_posn {
+	struct sof_ipc_reply rhdr;
+	uint32_t host_offset;	/* Offset of DMA host buffer */
+	uint32_t overflow;	/* overflow bytes if any */
+	uint32_t messages;	/* total trace messages */
+}  __packed;
+
+/* Values used in sof_ipc_trace_filter_elem: */
+
+/* bits 6..0 */
+#define SOF_IPC_TRACE_FILTER_ELEM_SET_LEVEL	0x01	/**< trace level for selected components */
+#define SOF_IPC_TRACE_FILTER_ELEM_BY_UUID	0x02	/**< filter by uuid key */
+#define SOF_IPC_TRACE_FILTER_ELEM_BY_PIPE	0x03	/**< filter by pipeline */
+#define SOF_IPC_TRACE_FILTER_ELEM_BY_COMP	0x04	/**< filter by component id */
+
+/* bit 7 */
+#define SOF_IPC_TRACE_FILTER_ELEM_FIN		0x80	/**< mark last filter in set */
+
+/* bits 31..8: Unused */
+
+/** part of sof_ipc_trace_filter, ABI3.17 */
+struct sof_ipc_trace_filter_elem {
+	uint32_t key;		/**< SOF_IPC_TRACE_FILTER_ELEM_ {LEVEL, UUID, COMP, PIPE} */
+	uint32_t value;		/**< element value */
+} __packed;
+
+/** Runtime tracing filtration data - SOF_IPC_TRACE_FILTER_UPDATE, ABI3.17 */
+struct sof_ipc_trace_filter {
+	struct sof_ipc_cmd_hdr hdr;	/**< IPC command header */
+	uint32_t elem_cnt;		/**< number of entries in elems[] array */
+	uint32_t reserved[8];		/**< reserved for future usage */
+	/** variable size array with new filtering settings */
+	struct sof_ipc_trace_filter_elem elems[];
+} __packed;
+
+/*
+ * Commom debug
+ */
+
+/*
+ * SOF panic codes
+ */
+#define SOF_IPC_PANIC_MAGIC			0x0dead000
+#define SOF_IPC_PANIC_MAGIC_MASK		0x0ffff000
+#define SOF_IPC_PANIC_CODE_MASK			0x00000fff
+#define SOF_IPC_PANIC_MEM			(SOF_IPC_PANIC_MAGIC | 0x0)
+#define SOF_IPC_PANIC_WORK			(SOF_IPC_PANIC_MAGIC | 0x1)
+#define SOF_IPC_PANIC_IPC			(SOF_IPC_PANIC_MAGIC | 0x2)
+#define SOF_IPC_PANIC_ARCH			(SOF_IPC_PANIC_MAGIC | 0x3)
+#define SOF_IPC_PANIC_PLATFORM			(SOF_IPC_PANIC_MAGIC | 0x4)
+#define SOF_IPC_PANIC_TASK			(SOF_IPC_PANIC_MAGIC | 0x5)
+#define SOF_IPC_PANIC_EXCEPTION			(SOF_IPC_PANIC_MAGIC | 0x6)
+#define SOF_IPC_PANIC_DEADLOCK			(SOF_IPC_PANIC_MAGIC | 0x7)
+#define SOF_IPC_PANIC_STACK			(SOF_IPC_PANIC_MAGIC | 0x8)
+#define SOF_IPC_PANIC_IDLE			(SOF_IPC_PANIC_MAGIC | 0x9)
+#define SOF_IPC_PANIC_WFI			(SOF_IPC_PANIC_MAGIC | 0xa)
+#define SOF_IPC_PANIC_ASSERT			(SOF_IPC_PANIC_MAGIC | 0xb)
+
+/* panic info include filename and line number
+ * filename array will not include null terminator if fully filled
+ */
+struct sof_ipc_panic_info {
+	struct sof_ipc_hdr hdr;
+	uint32_t code;			/* SOF_IPC_PANIC_ */
+	uint8_t filename[SOF_TRACE_FILENAME_SIZE];
+	uint32_t linenum;
+}  __packed;
+
+#endif