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, 28 insertions, 0 deletions

diff --git a/include/net/rawv6.h b/include/net/rawv6.h
new file mode 100644
index 000000000..82810cbe3
--- /dev/null
+++ b/include/net/rawv6.h
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _NET_RAWV6_H
+#define _NET_RAWV6_H
+
+#include <net/protocol.h>
+#include <net/raw.h>
+
+extern struct raw_hashinfo raw_v6_hashinfo;
+bool raw_v6_match(struct net *net, const struct sock *sk, unsigned short num,
+		  const struct in6_addr *loc_addr,
+		  const struct in6_addr *rmt_addr, int dif, int sdif);
+
+int raw_abort(struct sock *sk, int err);
+
+void raw6_icmp_error(struct sk_buff *, int nexthdr,
+		u8 type, u8 code, int inner_offset, __be32);
+bool raw6_local_deliver(struct sk_buff *, int);
+
+int rawv6_rcv(struct sock *sk, struct sk_buff *skb);
+
+#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
+int rawv6_mh_filter_register(int (*filter)(struct sock *sock,
+					   struct sk_buff *skb));
+int rawv6_mh_filter_unregister(int (*filter)(struct sock *sock,
+					     struct sk_buff *skb));
+#endif
+
+#endif