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 --- arch/powerpc/sysdev/dart.h | 64 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 64 insertions(+) create mode 100644 arch/powerpc/sysdev/dart.h (limited to 'arch/powerpc/sysdev/dart.h') diff --git a/arch/powerpc/sysdev/dart.h b/arch/powerpc/sysdev/dart.h new file mode 100644 index 000000000..7f5df03d3 --- /dev/null +++ b/arch/powerpc/sysdev/dart.h @@ -0,0 +1,64 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright (C) 2004 Olof Johansson , IBM Corporation + */ + +#ifndef _POWERPC_SYSDEV_DART_H +#define _POWERPC_SYSDEV_DART_H + + +/* Offset from base to control register */ +#define DART_CNTL 0 + +/* Offset from base to exception register */ +#define DART_EXCP_U3 0x10 +/* Offset from base to TLB tag registers */ +#define DART_TAGS_U3 0x1000 + +/* U4 registers */ +#define DART_BASE_U4 0x10 +#define DART_SIZE_U4 0x20 +#define DART_EXCP_U4 0x30 +#define DART_TAGS_U4 0x1000 + +/* Control Register fields */ + +/* U3 registers */ +#define DART_CNTL_U3_BASE_MASK 0xfffff +#define DART_CNTL_U3_BASE_SHIFT 12 +#define DART_CNTL_U3_FLUSHTLB 0x400 +#define DART_CNTL_U3_ENABLE 0x200 +#define DART_CNTL_U3_SIZE_MASK 0x1ff +#define DART_CNTL_U3_SIZE_SHIFT 0 + +/* U4 registers */ +#define DART_BASE_U4_BASE_MASK 0xffffff +#define DART_BASE_U4_BASE_SHIFT 0 +#define DART_CNTL_U4_ENABLE 0x80000000 +#define DART_CNTL_U4_IONE 0x40000000 +#define DART_CNTL_U4_FLUSHTLB 0x20000000 +#define DART_CNTL_U4_IDLE 0x10000000 +#define DART_CNTL_U4_PAR_EN 0x08000000 +#define DART_CNTL_U4_IONE_MASK 0x07ffffff +#define DART_SIZE_U4_SIZE_MASK 0x1fff +#define DART_SIZE_U4_SIZE_SHIFT 0 + +#define DART_REG(r) (dart + ((r) >> 2)) +#define DART_IN(r) (in_be32(DART_REG(r))) +#define DART_OUT(r,v) (out_be32(DART_REG(r), (v))) + + +/* size of table in pages */ + + +/* DART table fields */ + +#define DARTMAP_VALID 0x80000000 +#define DARTMAP_RPNMASK 0x00ffffff + + +#define DART_PAGE_SHIFT 12 +#define DART_PAGE_SIZE (1 << DART_PAGE_SHIFT) + + +#endif /* _POWERPC_SYSDEV_DART_H */ -- cgit v1.3.1