summaryrefslogtreecommitdiffstats
path: root/include/uapi/asm-generic/mman.h
diff options
context:
space:
mode:
authorSean Christopherson <seanjc@google.com>2026-09-23 09:37:21 -0700
committerPaolo Bonzini <pbonzini@redhat.com>2026-09-26 00:39:55 -0400
commit93de2a6a4b91b72607136dd656edf03fb399d27f (patch)
tree9220c76eb23cb39a146fac9692ee69afa4aa3135 /include/uapi/asm-generic/mman.h
downloadlinux-stable-93de2a6a4b91b72607136dd656edf03fb399d27f.tar.gz
linux-stable-93de2a6a4b91b72607136dd656edf03fb399d27f.zip
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>
Diffstat (limited to 'include/uapi/asm-generic/mman.h')
-rw-r--r--include/uapi/asm-generic/mman.h26
1 files changed, 26 insertions, 0 deletions
diff --git a/include/uapi/asm-generic/mman.h b/include/uapi/asm-generic/mman.h
new file mode 100644
index 000000000..5e3d61ddb
--- /dev/null
+++ b/include/uapi/asm-generic/mman.h
@@ -0,0 +1,26 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+#ifndef __ASM_GENERIC_MMAN_H
+#define __ASM_GENERIC_MMAN_H
+
+#include <asm-generic/mman-common.h>
+
+#define MAP_GROWSDOWN 0x0100 /* stack-like segment */
+#define MAP_DENYWRITE 0x0800 /* ETXTBSY */
+#define MAP_EXECUTABLE 0x1000 /* mark it as an executable */
+#define MAP_LOCKED 0x2000 /* pages are locked */
+#define MAP_NORESERVE 0x4000 /* don't check for reservations */
+
+/*
+ * Bits [26:31] are reserved, see asm-generic/hugetlb_encode.h
+ * for MAP_HUGETLB usage
+ */
+
+#define MCL_CURRENT 1 /* lock all current mappings */
+#define MCL_FUTURE 2 /* lock all future mappings */
+#define MCL_ONFAULT 4 /* lock all pages that are faulted in */
+
+#define SHADOW_STACK_SET_TOKEN (1ULL << 0) /* Set up a restore token in the shadow stack */
+#define SHADOW_STACK_SET_MARKER (1ULL << 1) /* Set up a top of stack marker in the shadow stack */
+
+
+#endif /* __ASM_GENERIC_MMAN_H */