kernel - lapic pointer was still not quite correctly initialized

* A conditional in the new MADT code was bypassing the lapic pointer
  mapping in certain circumstances, causing the machine to lockup in the
  low level boot.

diff --git a/sys/platform/pc64/x86_64/mp_machdep.c b/sys/platform/pc64/x86_64/mp_machdep.c
index b729248..0f17b7f 100644 (file)
--- a/sys/platform/pc64/x86_64/mp_machdep.c
+++ b/sys/platform/pc64/x86_64/mp_machdep.c
@@ -576,6 +576,12 @@ mp_enable(u_int boot_addr)
 
                /* post scan cleanup */
                mptable_fix();
+
+               /*
+                * lapic not mapped yet (pmap_init is called too late)
+                */
+               lapic = pmap_mapdev_uncacheable(cpu_apic_address,
+                                               sizeof(struct LAPIC));
        } else {
                vm_paddr_t madt_paddr;
                int bsp_apic_id;
@@ -589,9 +595,12 @@ mp_enable(u_int boot_addr)
                        panic("mp_enable: no local apic (madt)!\n");
 
                /*
+                * lapic not mapped yet (pmap_init is called too late)
+                *
                 * XXX: where is the best place to set lapic?
                 */
-               lapic = pmap_mapdev_uncacheable(cpu_apic_address, sizeof(struct LAPIC));
+               lapic = pmap_mapdev_uncacheable(cpu_apic_address,
+                                               sizeof(struct LAPIC));
 
                bsp_apic_id = (lapic->id & 0xff000000) >> 24;
                if (madt_pass2(madt_paddr, bsp_apic_id))