From 93de2a6a4b91b72607136dd656edf03fb399d27f Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Wed, 23 Sep 2026 09:37:21 -0700 Subject: KVM: SEV: Do cache maintenance on the source VM during intra-host migration 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 Signed-off-by: Sean Christopherson Message-ID: <20260923163721.1584779-3-seanjc@google.com> Signed-off-by: Paolo Bonzini --- include/net/tun_proto.h | 50 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+) create mode 100644 include/net/tun_proto.h (limited to 'include/net/tun_proto.h') diff --git a/include/net/tun_proto.h b/include/net/tun_proto.h new file mode 100644 index 000000000..7b0de7852 --- /dev/null +++ b/include/net/tun_proto.h @@ -0,0 +1,50 @@ +#ifndef __NET_TUN_PROTO_H +#define __NET_TUN_PROTO_H + +#include +#include + +/* One byte protocol values as defined by VXLAN-GPE and NSH. These will + * hopefully get a shared IANA registry. + */ +#define TUN_P_IPV4 0x01 +#define TUN_P_IPV6 0x02 +#define TUN_P_ETHERNET 0x03 +#define TUN_P_NSH 0x04 +#define TUN_P_MPLS_UC 0x05 + +static inline __be16 tun_p_to_eth_p(u8 proto) +{ + switch (proto) { + case TUN_P_IPV4: + return htons(ETH_P_IP); + case TUN_P_IPV6: + return htons(ETH_P_IPV6); + case TUN_P_ETHERNET: + return htons(ETH_P_TEB); + case TUN_P_NSH: + return htons(ETH_P_NSH); + case TUN_P_MPLS_UC: + return htons(ETH_P_MPLS_UC); + } + return 0; +} + +static inline u8 tun_p_from_eth_p(__be16 proto) +{ + switch (proto) { + case htons(ETH_P_IP): + return TUN_P_IPV4; + case htons(ETH_P_IPV6): + return TUN_P_IPV6; + case htons(ETH_P_TEB): + return TUN_P_ETHERNET; + case htons(ETH_P_NSH): + return TUN_P_NSH; + case htons(ETH_P_MPLS_UC): + return TUN_P_MPLS_UC; + } + return 0; +} + +#endif -- cgit v1.3.1