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Marc Zyngier authored
* kvm-arm64/mpidr-reset: : . : Fixes for CLIDR_EL1 and MPIDR_EL1 being accidentally mutable across : a vcpu reset, courtesy of Oliver. From the cover letter: : : "For VM-wide feature ID registers we ensure they get initialized once for : the lifetime of a VM. On the other hand, vCPU-local feature ID registers : get re-initialized on every vCPU reset, potentially clobbering the : values userspace set up. : : MPIDR_EL1 and CLIDR_EL1 are the only registers in this space that we : allow userspace to modify for now. Clobbering the value of MPIDR_EL1 has : some disastrous side effects as the compressed index used by the : MPIDR-to-vCPU lookup table assumes MPIDR_EL1 is immutable after KVM_RUN. : : Series + reproducer test case to address the problem of KVM wiping out : userspace changes to these registers. Note that there are still some : differences between VM and vCPU scoped feature ID registers from the : perspective of userspace. We do not allow the value of VM-scope : registers to change after KVM_RUN, but vCPU registers remain mutable." : . KVM: selftests: arm64: Test vCPU-scoped feature ID registers KVM: selftests: arm64: Test that feature ID regs survive a reset KVM: selftests: arm64: Store expected register value in set_id_regs KVM: selftests: arm64: Rename helper in set_id_regs to imply VM scope KVM: arm64: Only reset vCPU-scoped feature ID regs once KVM: arm64: Reset VM feature ID regs from kvm_reset_sys_regs() KVM: arm64: Rename is_id_reg() to imply VM scope Signed-off-by: Marc Zyngier <maz@kernel.org>
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