[PATCH v3 0/10] KVM: x86: allow compiling out SMM support

From: Paolo Bonzini
Date: Thu Oct 27 2022 - 12:49:54 EST


Some users of KVM implement the UEFI variable store through a paravirtual device
that does not require the "SMM lockbox" component of edk2; allow them to
compile out system management mode, which is not a full implementation
especially in how it interacts with nested virtualization.

In order to limit the number and especially the size of the #ifdefs,
the first 4 patches move most SMM code to a completely new file in
arch/x86/kvm. Patch 5 is the main change to introduce the Kconfig
symbol and key smm.c's compilation off it; patches 6-10 instead
eliminate other bits of SMM code that remain outside smm.c.

Paolo

v2->v3: remove kvm_smm_changed stub as well as more code in KVM_GET_VCPU_EVENTS
leave kvm_apic_init_sipi_allowed inline
change placement Kconfig to generate the right menu hierarchy

Paolo Bonzini (9):
KVM: x86: start moving SMM-related functions to new files
KVM: x86: move SMM entry to a new file
KVM: x86: move SMM exit to a new file
KVM: x86: do not go through ctxt->ops when emulating rsm
KVM: allow compiling out SMM support
KVM: x86: compile out vendor-specific code if SMM is disabled
KVM: x86: remove SMRAM address space if SMM is not supported
KVM: x86: do not define KVM_REQ_SMI if SMM disabled
KVM: zero output of KVM_GET_VCPU_EVENTS before filling in the struct

Sean Christopherson (1):
KVM: x86: do not define SMM-related constants if SMM disabled

arch/x86/include/asm/kvm-x86-ops.h | 2 +
arch/x86/include/asm/kvm_host.h | 25 +-
arch/x86/kvm/Kconfig | 11 +
arch/x86/kvm/Makefile | 1 +
arch/x86/kvm/emulate.c | 355 +----------
arch/x86/kvm/kvm_cache_regs.h | 5 -
arch/x86/kvm/kvm_emulate.h | 47 +-
arch/x86/kvm/lapic.c | 8 +-
arch/x86/kvm/lapic.h | 2 +-
arch/x86/kvm/mmu/mmu.c | 1 +
arch/x86/kvm/smm.c | 576 ++++++++++++++++++
arch/x86/kvm/smm.h | 37 ++
arch/x86/kvm/svm/nested.c | 3 +
arch/x86/kvm/svm/svm.c | 11 +-
arch/x86/kvm/vmx/nested.c | 1 +
arch/x86/kvm/vmx/vmx.c | 7 +
arch/x86/kvm/x86.c | 371 ++---------
tools/testing/selftests/kvm/x86_64/smm_test.c | 2 +
18 files changed, 741 insertions(+), 724 deletions(-)
create mode 100644 arch/x86/kvm/smm.c
create mode 100644 arch/x86/kvm/smm.h

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2.31.1