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, 67 insertions, 0 deletions

diff --git a/sound/soc/sof/ipc3-priv.h b/sound/soc/sof/ipc3-priv.h
new file mode 100644
index 000000000..866c5f67b
--- /dev/null
+++ b/sound/soc/sof/ipc3-priv.h
@@ -0,0 +1,67 @@
+/* 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 Intel Corporation
+ */
+
+#ifndef __SOUND_SOC_SOF_IPC3_PRIV_H
+#define __SOUND_SOC_SOF_IPC3_PRIV_H
+
+#include "sof-priv.h"
+
+/* IPC3 specific ops */
+extern const struct sof_ipc_pcm_ops ipc3_pcm_ops;
+extern const struct sof_ipc_tplg_ops ipc3_tplg_ops;
+extern const struct sof_ipc_tplg_control_ops tplg_ipc3_control_ops;
+extern const struct sof_ipc_fw_loader_ops ipc3_loader_ops;
+extern const struct sof_ipc_fw_tracing_ops ipc3_dtrace_ops;
+
+/* helpers for fw_ready and ext_manifest parsing */
+int sof_ipc3_get_ext_windows(struct snd_sof_dev *sdev,
+			     const struct sof_ipc_ext_data_hdr *ext_hdr);
+int sof_ipc3_get_cc_info(struct snd_sof_dev *sdev,
+			 const struct sof_ipc_ext_data_hdr *ext_hdr);
+int sof_ipc3_validate_fw_version(struct snd_sof_dev *sdev);
+
+/* dtrace position update */
+int ipc3_dtrace_posn_update(struct snd_sof_dev *sdev,
+			    struct sof_ipc_dma_trace_posn *posn);
+/* RX handler backend */
+void sof_ipc3_do_rx_work(struct snd_sof_dev *sdev, struct sof_ipc_cmd_hdr *hdr, void *msg_buf);
+
+/* dtrace platform callback wrappers */
+static inline int sof_dtrace_host_init(struct snd_sof_dev *sdev,
+				       struct snd_dma_buffer *dmatb,
+				       struct sof_ipc_dma_trace_params_ext *dtrace_params)
+{
+	const struct snd_sof_dsp_ops *dsp_ops = sdev->pdata->desc->ops;
+
+	if (dsp_ops->trace_init)
+		return dsp_ops->trace_init(sdev, dmatb, dtrace_params);
+
+	return 0;
+}
+
+static inline int sof_dtrace_host_release(struct snd_sof_dev *sdev)
+{
+	const struct snd_sof_dsp_ops *dsp_ops = sdev->pdata->desc->ops;
+
+	if (dsp_ops->trace_release)
+		return dsp_ops->trace_release(sdev);
+
+	return 0;
+}
+
+static inline int sof_dtrace_host_trigger(struct snd_sof_dev *sdev, int cmd)
+{
+	const struct snd_sof_dsp_ops *dsp_ops = sdev->pdata->desc->ops;
+
+	if (dsp_ops->trace_trigger)
+		return dsp_ops->trace_trigger(sdev, cmd);
+
+	return 0;
+}
+
+#endif