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, 168 insertions, 0 deletions

diff --git a/include/trace/misc/rdma.h b/include/trace/misc/rdma.h
new file mode 100644
index 000000000..81bb454fc
--- /dev/null
+++ b/include/trace/misc/rdma.h
@@ -0,0 +1,168 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2017 Oracle.  All rights reserved.
+ */
+
+/*
+ * enum ib_event_type, from include/rdma/ib_verbs.h
+ */
+#define IB_EVENT_LIST				\
+	ib_event(CQ_ERR)			\
+	ib_event(QP_FATAL)			\
+	ib_event(QP_REQ_ERR)			\
+	ib_event(QP_ACCESS_ERR)			\
+	ib_event(COMM_EST)			\
+	ib_event(SQ_DRAINED)			\
+	ib_event(PATH_MIG)			\
+	ib_event(PATH_MIG_ERR)			\
+	ib_event(DEVICE_FATAL)			\
+	ib_event(PORT_ACTIVE)			\
+	ib_event(PORT_ERR)			\
+	ib_event(LID_CHANGE)			\
+	ib_event(PKEY_CHANGE)			\
+	ib_event(SM_CHANGE)			\
+	ib_event(SRQ_ERR)			\
+	ib_event(SRQ_LIMIT_REACHED)		\
+	ib_event(QP_LAST_WQE_REACHED)		\
+	ib_event(CLIENT_REREGISTER)		\
+	ib_event(GID_CHANGE)			\
+	ib_event_end(WQ_FATAL)
+
+#undef ib_event
+#undef ib_event_end
+
+#define ib_event(x)		TRACE_DEFINE_ENUM(IB_EVENT_##x);
+#define ib_event_end(x)		TRACE_DEFINE_ENUM(IB_EVENT_##x);
+
+IB_EVENT_LIST
+
+#undef ib_event
+#undef ib_event_end
+
+#define ib_event(x)		{ IB_EVENT_##x, #x },
+#define ib_event_end(x)		{ IB_EVENT_##x, #x }
+
+#define rdma_show_ib_event(x) \
+		__print_symbolic(x, IB_EVENT_LIST)
+
+/*
+ * enum ib_wc_status type, from include/rdma/ib_verbs.h
+ */
+#define IB_WC_STATUS_LIST			\
+	ib_wc_status(SUCCESS)			\
+	ib_wc_status(LOC_LEN_ERR)		\
+	ib_wc_status(LOC_QP_OP_ERR)		\
+	ib_wc_status(LOC_EEC_OP_ERR)		\
+	ib_wc_status(LOC_PROT_ERR)		\
+	ib_wc_status(WR_FLUSH_ERR)		\
+	ib_wc_status(MW_BIND_ERR)		\
+	ib_wc_status(BAD_RESP_ERR)		\
+	ib_wc_status(LOC_ACCESS_ERR)		\
+	ib_wc_status(REM_INV_REQ_ERR)		\
+	ib_wc_status(REM_ACCESS_ERR)		\
+	ib_wc_status(REM_OP_ERR)		\
+	ib_wc_status(RETRY_EXC_ERR)		\
+	ib_wc_status(RNR_RETRY_EXC_ERR)		\
+	ib_wc_status(LOC_RDD_VIOL_ERR)		\
+	ib_wc_status(REM_INV_RD_REQ_ERR)	\
+	ib_wc_status(REM_ABORT_ERR)		\
+	ib_wc_status(INV_EECN_ERR)		\
+	ib_wc_status(INV_EEC_STATE_ERR)		\
+	ib_wc_status(FATAL_ERR)			\
+	ib_wc_status(RESP_TIMEOUT_ERR)		\
+	ib_wc_status_end(GENERAL_ERR)
+
+#undef ib_wc_status
+#undef ib_wc_status_end
+
+#define ib_wc_status(x)		TRACE_DEFINE_ENUM(IB_WC_##x);
+#define ib_wc_status_end(x)	TRACE_DEFINE_ENUM(IB_WC_##x);
+
+IB_WC_STATUS_LIST
+
+#undef ib_wc_status
+#undef ib_wc_status_end
+
+#define ib_wc_status(x)		{ IB_WC_##x, #x },
+#define ib_wc_status_end(x)	{ IB_WC_##x, #x }
+
+#define rdma_show_wc_status(x) \
+		__print_symbolic(x, IB_WC_STATUS_LIST)
+
+/*
+ * enum ib_cm_event_type, from include/rdma/ib_cm.h
+ */
+#define IB_CM_EVENT_LIST			\
+	ib_cm_event(REQ_ERROR)			\
+	ib_cm_event(REQ_RECEIVED)		\
+	ib_cm_event(REP_ERROR)			\
+	ib_cm_event(REP_RECEIVED)		\
+	ib_cm_event(RTU_RECEIVED)		\
+	ib_cm_event(USER_ESTABLISHED)		\
+	ib_cm_event(DREQ_ERROR)			\
+	ib_cm_event(DREQ_RECEIVED)		\
+	ib_cm_event(DREP_RECEIVED)		\
+	ib_cm_event(TIMEWAIT_EXIT)		\
+	ib_cm_event(MRA_RECEIVED)		\
+	ib_cm_event(REJ_RECEIVED)		\
+	ib_cm_event(LAP_ERROR)			\
+	ib_cm_event(LAP_RECEIVED)		\
+	ib_cm_event(APR_RECEIVED)		\
+	ib_cm_event(SIDR_REQ_ERROR)		\
+	ib_cm_event(SIDR_REQ_RECEIVED)		\
+	ib_cm_event_end(SIDR_REP_RECEIVED)
+
+#undef ib_cm_event
+#undef ib_cm_event_end
+
+#define ib_cm_event(x)		TRACE_DEFINE_ENUM(IB_CM_##x);
+#define ib_cm_event_end(x)	TRACE_DEFINE_ENUM(IB_CM_##x);
+
+IB_CM_EVENT_LIST
+
+#undef ib_cm_event
+#undef ib_cm_event_end
+
+#define ib_cm_event(x)		{ IB_CM_##x, #x },
+#define ib_cm_event_end(x)	{ IB_CM_##x, #x }
+
+#define rdma_show_ib_cm_event(x) \
+		__print_symbolic(x, IB_CM_EVENT_LIST)
+
+/*
+ * enum rdma_cm_event_type, from include/rdma/rdma_cm.h
+ */
+#define RDMA_CM_EVENT_LIST			\
+	rdma_cm_event(ADDR_RESOLVED)		\
+	rdma_cm_event(ADDR_ERROR)		\
+	rdma_cm_event(ROUTE_RESOLVED)		\
+	rdma_cm_event(ROUTE_ERROR)		\
+	rdma_cm_event(CONNECT_REQUEST)		\
+	rdma_cm_event(CONNECT_RESPONSE)		\
+	rdma_cm_event(CONNECT_ERROR)		\
+	rdma_cm_event(UNREACHABLE)		\
+	rdma_cm_event(REJECTED)			\
+	rdma_cm_event(ESTABLISHED)		\
+	rdma_cm_event(DISCONNECTED)		\
+	rdma_cm_event(DEVICE_REMOVAL)		\
+	rdma_cm_event(MULTICAST_JOIN)		\
+	rdma_cm_event(MULTICAST_ERROR)		\
+	rdma_cm_event(ADDR_CHANGE)		\
+	rdma_cm_event_end(TIMEWAIT_EXIT)
+
+#undef rdma_cm_event
+#undef rdma_cm_event_end
+
+#define rdma_cm_event(x)	TRACE_DEFINE_ENUM(RDMA_CM_EVENT_##x);
+#define rdma_cm_event_end(x)	TRACE_DEFINE_ENUM(RDMA_CM_EVENT_##x);
+
+RDMA_CM_EVENT_LIST
+
+#undef rdma_cm_event
+#undef rdma_cm_event_end
+
+#define rdma_cm_event(x)	{ RDMA_CM_EVENT_##x, #x },
+#define rdma_cm_event_end(x)	{ RDMA_CM_EVENT_##x, #x }
+
+#define rdma_show_cm_event(x) \
+		__print_symbolic(x, RDMA_CM_EVENT_LIST)