M2 MacBook Air has mismatched CCSIDR associativity bits, which makes the bits a KVM vCPU sees inconsistent when migrating. It also makes QEMU fail restoring the vCPU registers because QEMU saves and restores all of the registers including CCSIDRs, and if the vCPU migrated among physical CPUs between saving and restoring, it tries to restore CCSIDR values that mismatch with the current physical CPU, which causes EFAULT. Trap CCSIDRs if there are CCSIDR value msimatches, and override the associativity bits when handling the trap. Akihiko Odaki (3): KVM: arm64: Make CCSIDRs consistent arm64: errata: Check for mismatched cache associativity KVM: arm64: Handle CCSIDR associativity mismatches arch/arm64/include/asm/cache.h | 3 ++ arch/arm64/include/asm/cpu.h | 1 + arch/arm64/include/asm/cpufeature.h | 8 +++++ arch/arm64/include/asm/kvm_emulate.h | 10 ++++-- arch/arm64/include/asm/sysreg.h | 7 ++++ arch/arm64/kernel/cacheinfo.c | 4 +-- arch/arm64/kernel/cpu_errata.c | 52 ++++++++++++++++++++++++++++ arch/arm64/kernel/cpufeature.c | 4 +++ arch/arm64/kernel/cpuinfo.c | 30 ++++++++++++++++ arch/arm64/kvm/sys_regs.c | 50 ++++++++++++++------------ arch/arm64/tools/cpucaps | 1 + 11 files changed, 144 insertions(+), 26 deletions(-) -- 2.38.1 _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
