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/uapi/fwctl/pds.h | 62 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) create mode 100644 include/uapi/fwctl/pds.h (limited to 'include/uapi/fwctl/pds.h') diff --git a/include/uapi/fwctl/pds.h b/include/uapi/fwctl/pds.h new file mode 100644 index 000000000..66be32411 --- /dev/null +++ b/include/uapi/fwctl/pds.h @@ -0,0 +1,62 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +/* Copyright(c) Advanced Micro Devices, Inc */ + +/* + * fwctl interface info for pds_fwctl + */ + +#ifndef _UAPI_FWCTL_PDS_H_ +#define _UAPI_FWCTL_PDS_H_ + +#include + +/** + * struct fwctl_info_pds + * @uctx_caps: bitmap of firmware capabilities + * + * Return basic information about the FW interface available. + */ +struct fwctl_info_pds { + __u32 uctx_caps; +}; + +/** + * enum pds_fwctl_capabilities + * @PDS_FWCTL_QUERY_CAP: firmware can be queried for information + * @PDS_FWCTL_SEND_CAP: firmware can be sent commands + */ +enum pds_fwctl_capabilities { + PDS_FWCTL_QUERY_CAP = 0, + PDS_FWCTL_SEND_CAP, +}; + +/** + * struct fwctl_rpc_pds + * @in.op: requested operation code + * @in.ep: firmware endpoint to operate on + * @in.rsvd: reserved + * @in.len: length of payload data + * @in.payload: address of payload buffer + * @in: rpc in parameters + * @out.retval: operation result value + * @out.rsvd: reserved + * @out.len: length of result data buffer + * @out.payload: address of payload data buffer + * @out: rpc out parameters + */ +struct fwctl_rpc_pds { + struct { + __u32 op; + __u32 ep; + __u32 rsvd; + __u32 len; + __aligned_u64 payload; + } in; + struct { + __u32 retval; + __u32 rsvd[2]; + __u32 len; + __aligned_u64 payload; + } out; +}; +#endif /* _UAPI_FWCTL_PDS_H_ */ -- cgit v1.3.1