On vcpu reset, we expect all the registers to be brought back to their initial state, which happens to be a bunch of zeroes.
However, some recent commit broke this, and is now leaving a bunch of registers (such as the FP state) with whatever was left by the guest. My bad. Zero the reset of the state (32bit SPSRs and FPSIMD state). Cc: [email protected] Fixes: e47c2055c68e ("KVM: arm64: Make struct kvm_regs userspace-only") Signed-off-by: Marc Zyngier <[email protected]> --- Notes: v2: Only reset the FPSIMD state and the AArch32 SPSRs to avoid corrupting CNTVOFF in creative ways. arch/arm64/kvm/reset.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c index bd354cd45d28..4b5acd84b8c8 100644 --- a/arch/arm64/kvm/reset.c +++ b/arch/arm64/kvm/reset.c @@ -242,6 +242,11 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu) /* Reset core registers */ memset(vcpu_gp_regs(vcpu), 0, sizeof(*vcpu_gp_regs(vcpu))); + memset(&vcpu->arch.ctxt.fp_regs, 0, sizeof(vcpu->arch.ctxt.fp_regs)); + vcpu->arch.ctxt.spsr_abt = 0; + vcpu->arch.ctxt.spsr_und = 0; + vcpu->arch.ctxt.spsr_irq = 0; + vcpu->arch.ctxt.spsr_fiq = 0; vcpu_gp_regs(vcpu)->pstate = pstate; /* Reset system registers */ -- 2.30.2 _______________________________________________ kvmarm mailing list [email protected] https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
