On Fri, Mar 20, 2020 at 11:26:43AM +0100, Laurent Dufour wrote: > When the call to UV_REGISTER_MEM_SLOT is failing, for instance because > there is not enough free secured memory, the Hypervisor (HV) has to call > UV_RETURN to report the error to the Ultravisor (UV). Then the UV will call > H_SVM_INIT_ABORT to abort the securing phase and go back to the calling VM. > > If the kvm->arch.secure_guest is not set, in the return path rfid is called > but there is no valid context to get back to the SVM since the Hcall has > been routed by the Ultravisor. > > Move the setting of kvm->arch.secure_guest earlier in > kvmppc_h_svm_init_start() so in the return path, UV_RETURN will be called > instead of rfid. > > Cc: Bharata B Rao <bharata@xxxxxxxxxxxxx> > Cc: Paul Mackerras <paulus@xxxxxxxxxx> > Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> > Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> > Signed-off-by: Laurent Dufour <ldufour@xxxxxxxxxxxxx> > --- > arch/powerpc/kvm/book3s_hv_uvmem.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/powerpc/kvm/book3s_hv_uvmem.c b/arch/powerpc/kvm/book3s_hv_uvmem.c > index 79b1202b1c62..68dff151315c 100644 > --- a/arch/powerpc/kvm/book3s_hv_uvmem.c > +++ b/arch/powerpc/kvm/book3s_hv_uvmem.c > @@ -209,6 +209,8 @@ unsigned long kvmppc_h_svm_init_start(struct kvm *kvm) > int ret = H_SUCCESS; > int srcu_idx; > > + kvm->arch.secure_guest = KVMPPC_SECURE_INIT_START; > + > if (!kvmppc_uvmem_bitmap) > return H_UNSUPPORTED; > > @@ -233,7 +235,6 @@ unsigned long kvmppc_h_svm_init_start(struct kvm *kvm) > goto out; > } > } > - kvm->arch.secure_guest |= KVMPPC_SECURE_INIT_START; There is an assumption that memory slots would have been registered with UV if KVMPPC_SECURE_INIT_START has been done. KVM_PPC_SVM_OFF ioctl will skip unregistration and other steps during reboot if KVMPPC_SECURE_INIT_START hasn't been done. Have you checked if that path isn't affected by this change? Regards, Bharata.
