KVM_PPC_ALLOCATE_HTAB ioctl can return -ENOMEM for KVM guests and QEMU never handled this correctly. But this didn't cause any problems till now as KVM_PPC_ALLOCATE_HTAB ioctl returned with smaller than requested HTAB when enough contiguous memory wasn't available in the host. After the proposed kernel change: https://patchwork.ozlabs.org/patch/530501/, KVM_PPC_ALLOCATE_HTAB ioctl will not fallback to lower sized HTAB allocation and will fail if requested HTAB size can't be met.
Check for such failures in QEMU and abort appropriately. This will prevent guest kernel from hanging/freezing during early boot by doing graceful exit when host is unable to allocate requested HTAB. Signed-off-by: Bharata B Rao <[email protected]> --- hw/ppc/spapr.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index e1202ce..ec6e141 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -1022,7 +1022,7 @@ static void spapr_alloc_htab(sPAPRMachineState *spapr) shift = kvmppc_reset_htab(spapr->htab_shift); - if (shift > 0) { + if (shift != 0) { /* Kernel handles htab, we don't need to allocate one */ if (shift != spapr->htab_shift) { error_setg(&error_abort, "Failed to allocate HTAB of requested size, try with smaller maxmem"); @@ -1055,7 +1055,7 @@ static void spapr_reset_htab(sPAPRMachineState *spapr) int index; shift = kvmppc_reset_htab(spapr->htab_shift); - if (shift > 0) { + if (shift != 0) { if (shift != spapr->htab_shift) { error_setg(&error_abort, "Requested HTAB allocation failed during reset"); } -- 2.1.0
