From: Aneesh Kumar K.V Date: Fri, 30 Mar 2018 11:57:24 +0000 (+0530) Subject: powerpc/kvm: Fix guest boot failure on Power9 since DAWR changes X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=ca9a16c3bc1582da62ef9c47fc22008447f7ae0e;p=openwrt%2Fstaging%2Fblogic.git powerpc/kvm: Fix guest boot failure on Power9 since DAWR changes SLOF checks for 'sc 1' (hypercall) support by issuing a hcall with H_SET_DABR. Since the recent commit e8ebedbf3131 ("KVM: PPC: Book3S HV: Return error from h_set_dabr() on POWER9") changed H_SET_DABR to return H_UNSUPPORTED on Power9, we see guest boot failures, the symptom is the boot seems to just stop in SLOF, eg: SLOF *************************************************************** QEMU Starting Build Date = Sep 24 2017 12:23:07 FW Version = buildd@ release 20170724 SLOF can cope if H_SET_DABR returns H_HARDWARE. So wwitch the return value to H_HARDWARE instead of H_UNSUPPORTED so that we don't break the guest boot. That does mean we return a different error to PowerVM in this case, but that's probably not a big concern. Fixes: e8ebedbf3131 ("KVM: PPC: Book3S HV: Return error from h_set_dabr() on POWER9") Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman --- diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S index 95c616f2da22..4e66f578e3cd 100644 --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S @@ -2575,7 +2575,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S) 2: BEGIN_FTR_SECTION /* POWER9 with disabled DAWR */ - li r3, H_UNSUPPORTED + li r3, H_HARDWARE blr END_FTR_SECTION_IFCLR(CPU_FTR_DAWR) /* Emulate H_SET_DABR/X on P8 for the sake of compat mode guests */