diff options
Diffstat (limited to 'arch/powerpc/kvm/book3s_hv.c')
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv.c | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 57d0835e56fd..917abda9e5ce 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -2517,10 +2517,24 @@ static int kvmppc_set_one_reg_hv(struct kvm_vcpu *vcpu, u64 id, r = set_vpa(vcpu, &vcpu->arch.dtl, addr, len); break; case KVM_REG_PPC_TB_OFFSET: + { /* round up to multiple of 2^24 */ - vcpu->arch.vcore->tb_offset = - ALIGN(set_reg_val(id, *val), 1UL << 24); + u64 tb_offset = ALIGN(set_reg_val(id, *val), 1UL << 24); + + /* + * Now that we know the timebase offset, update the + * decrementer expiry with a guest timebase value. If + * the userspace does not set DEC_EXPIRY, this ensures + * a migrated vcpu at least starts with an expired + * decrementer, which is better than a large one that + * causes a hang. + */ + if (!vcpu->arch.dec_expires && tb_offset) + vcpu->arch.dec_expires = get_tb() + tb_offset; + + vcpu->arch.vcore->tb_offset = tb_offset; break; + } case KVM_REG_PPC_LPCR: kvmppc_set_lpcr(vcpu, set_reg_val(id, *val), true); break; |