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| author | Paolo Bonzini <pbonzini@redhat.com> | 2025-08-27 04:37:40 -0400 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2025-08-27 04:41:35 -0400 |
| commit | a6ad54137af92535cfe32e19e5f3bc1bb7dbd383 (patch) | |
| tree | 0a5b8e5566f45aa5d7fc68f7acd5178b09c44546 /arch/x86/include/asm/kvm-x86-ops.h | |
| parent | 0dc4a751507177af24a2529d57dbe4a37e45b30c (diff) | |
| parent | 42188667be387867d2bf763d028654cbad046f7b (diff) | |
Merge branch 'guest-memfd-mmap' into HEAD
Add support for host userspace mapping of guest_memfd-backed memory for VM
types that do NOT use support KVM_MEMORY_ATTRIBUTE_PRIVATE (which isn't
precisely the same thing as CoCo VMs, since x86's SEV-MEM and SEV-ES have
no way to detect private vs. shared).
mmap() support paves the way for several evolving KVM use cases:
* Allows VMMs like Firecracker to run guests entirely backed by
guest_memfd [1]. This provides a unified memory management model for
both confidential and non-confidential guests, simplifying VMM design.
* Enhanced Security via direct map removal: When combined with Patrick's
series for direct map removal [2], this provides additional hardening
against Spectre-like transient execution attacks by eliminating the
need for host kernel direct maps of guest memory.
* Lays the groundwork for *restricted* mmap() support for guest_memfd-backed
memory on CoCo platforms [3] that permit in-place sharing of guest memory
with the host.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/include/asm/kvm-x86-ops.h')
| -rw-r--r-- | arch/x86/include/asm/kvm-x86-ops.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h index 18a5c3119e1a..62c3e4de3303 100644 --- a/arch/x86/include/asm/kvm-x86-ops.h +++ b/arch/x86/include/asm/kvm-x86-ops.h @@ -145,7 +145,7 @@ KVM_X86_OP_OPTIONAL_RET0(vcpu_get_apicv_inhibit_reasons); KVM_X86_OP_OPTIONAL(get_untagged_addr) KVM_X86_OP_OPTIONAL(alloc_apic_backing_page) KVM_X86_OP_OPTIONAL_RET0(gmem_prepare) -KVM_X86_OP_OPTIONAL_RET0(private_max_mapping_level) +KVM_X86_OP_OPTIONAL_RET0(gmem_max_mapping_level) KVM_X86_OP_OPTIONAL(gmem_invalidate) #undef KVM_X86_OP |