This reverts commit 7c3ded5735141ff4d049747c9f76672a8b737c49. On PowerNV, when a nested guest tries to use a feature prohibited by HFSCR, the nested hypervisor (L1) should get a H_FAC_UNAVAILABLE trap so that L1 can emulate the feature. But with the change introduced by commit 7c3ded573514 ("KVM: PPC: Book3S HV Nested: Stop forwarding all HFUs to L1") the L1 ends up getting a H_EMUL_ASSIST because of which, the L1 ends up injecting a SIGILL when L2 (nested guest) tries to use doorbells. Reviewed-by: Nicholas Piggin <npiggin@xxxxxxxxx> Signed-off-by: Gautam Menghani <gautam@xxxxxxxxxxxxx> --- arch/powerpc/kvm/book3s_hv.c | 31 ++----------------------------- 1 file changed, 2 insertions(+), 29 deletions(-) diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index ad8dc4ccdaab..0a8f143e0a75 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -2060,36 +2060,9 @@ static int kvmppc_handle_nested_exit(struct kvm_vcpu *vcpu) fallthrough; /* go to facility unavailable handler */ #endif - case BOOK3S_INTERRUPT_H_FAC_UNAVAIL: { - u64 cause = vcpu->arch.hfscr >> 56; - - /* - * Only pass HFU interrupts to the L1 if the facility is - * permitted but disabled by the L1's HFSCR, otherwise - * the interrupt does not make sense to the L1 so turn - * it into a HEAI. - */ - if (!(vcpu->arch.hfscr_permitted & (1UL << cause)) || - (vcpu->arch.nested_hfscr & (1UL << cause))) { - ppc_inst_t pinst; - vcpu->arch.trap = BOOK3S_INTERRUPT_H_EMUL_ASSIST; - - /* - * If the fetch failed, return to guest and - * try executing it again. - */ - r = kvmppc_get_last_inst(vcpu, INST_GENERIC, &pinst); - vcpu->arch.emul_inst = ppc_inst_val(pinst); - if (r != EMULATE_DONE) - r = RESUME_GUEST; - else - r = RESUME_HOST; - } else { - r = RESUME_HOST; - } - + case BOOK3S_INTERRUPT_H_FAC_UNAVAIL: + r = RESUME_HOST; break; - } case BOOK3S_INTERRUPT_HV_RM_HARD: vcpu->arch.trap = 0; -- 2.45.2