[PATCH 0/4] KVM: x86: MSR filtering and related fixes

Sean Christopherson
2021-03-16T18:45:43Z

Rework the MSR filtering implementation to treat a given filter instance
as an atomic unit, and to properly protect it with SRCU.

Fix two nVMX bugs related to MSR filtering (one directly, one indirectly),
and additional cleanup on top.

Regarding the macro insanity in patch 03, I verified the before and after
binary output for vmx_set_intercept_for_msr() was identical (this required
wrapping "if (msr <= 0x1fff)" with (un)likely in both the before and after
versions; gcc made seemingly random choices without forcing it to favor a
specific branch).

Sean Christopherson (4):
KVM: x86: Protect userspace MSR filter with SRCU, and set
atomically-ish
KVM: nVMX: Handle dynamic MSR intercept toggling
KVM: VMX: Macrofy the MSR bitmap getters and setters
KVM: nVMX: Clean up x2APIC MSR handling for L2

Documentation/virt/kvm/api.rst | 6 +-
arch/x86/include/asm/kvm_host.h | 17 ++--
arch/x86/kvm/vmx/nested.c | 161 +++++++++++++-------------------
arch/x86/kvm/vmx/vmx.c | 67 +------------
arch/x86/kvm/vmx/vmx.h | 32 +++++++
arch/x86/kvm/x86.c | 109 ++++++++++++---------
6 files changed, 176 insertions(+), 216 deletions(-)

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2.31.0.rc2.261.g7f71774620-goog