if (ret != 0) {
/*
* two parts from lib/swiotlb.c:
- * swiotlb size: user specified with swiotlb= or default.
- * swiotlb overflow buffer: now is hardcoded to 32k.
- * We round it to 8M for other buffers that
- * may need to stay low too.
+ * -swiotlb size: user-specified with swiotlb= or default.
+ *
+ * -swiotlb overflow buffer: now hardcoded to 32k. We round it
+ * to 8M for other buffers that may need to stay low too. Also
+ * make sure we allocate enough extra low memory so that we
+ * don't run out of DMA buffers for 32-bit devices.
*/
- low_size = swiotlb_size_or_default() + (8UL<<20);
+ low_size = max(swiotlb_size_or_default() + (8UL<<20), 256UL<<20);
auto_set = true;
} else {
/* passed with crashkernel=0,low ? */
init_cpu_to_node();
init_apic_mappings();
- if (x86_io_apic_ops.init)
- x86_io_apic_ops.init();
+ io_apic_init_mappings();
kvm_guest_init();