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author | Sean Christopherson <seanjc@google.com> | 2022-11-25 13:58:38 +0100 |
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committer | Paolo Bonzini <pbonzini@redhat.com> | 2022-11-28 19:33:25 +0100 |
commit | c4690d016182d271a862767145db8b2bc792f4a8 (patch) | |
tree | fcd1642b971fb2eda321154a67ee7a81e6131138 /Kbuild | |
parent | MAINTAINERS: Add KVM x86/xen maintainer list (diff) | |
download | linux-c4690d016182d271a862767145db8b2bc792f4a8.tar.xz linux-c4690d016182d271a862767145db8b2bc792f4a8.zip |
KVM: x86: Add BUILD_BUG_ON() to detect bad usage of "scattered" flags
Add a compile-time assert in the SF() macro to detect improper usage,
i.e. to detect passing in an X86_FEATURE_* flag that isn't actually
scattered by the kernel. Upcoming feature flags will be 100% KVM-only
and will have X86_FEATURE_* macros that point at a kvm_only_cpuid_leafs
word, not a kernel-defined word. Using SF() and thus boot_cpu_has() for
such feature flags would access memory beyond x86_capability[NCAPINTS]
and at best incorrectly hide a feature, and at worst leak kernel state to
userspace.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20221125125845.1182922-2-jiaxi.chen@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'Kbuild')
0 files changed, 0 insertions, 0 deletions