> The cpu_online_map stuff for hotplug cpu created a brand new bootstrap
> ordering problem for NUMA-Q. The mmapped portio region needs to be
> ioremapped early but ioremap attempts to do TLB shootdown, and
> smp_call_function() (called by flush_tlb_all()) deadlocks when
> cpu_online_map is uninitialized.
>
> Workaround (due to Matt Dobson) below.
>
>
>
> diff -Nur linux-2.5.23-vanilla/arch/i386/kernel/smp.c linux-2.5.23-patched/arch/i386/kernel/smp.c
> --- linux-2.5.23-vanilla/arch/i386/kernel/smp.c Tue Jun 18 19:11:47 2002
> +++ linux-2.5.23-patched/arch/i386/kernel/smp.c Mon Jul 8 14:52:32 2002
> @@ -569,7 +569,7 @@
> struct call_data_struct data;
> int cpus = num_online_cpus()-1;
>
> - if (!cpus)
> + if (cpus <= 0)
> return 0;
>
> data.func = func;
Would it be slightly less of a hack if we just move the ioremap down below
set_bit(0, &cpu_online_map); later on in smp_boot_cpus ? Untested patch
below. As long as we set up the xquad_portio remap before any other cpus
are online, I can't see it matters exactly when we do it ....
Either that, or we just define cpu_online_map to be =1 to start with.
M.
--- virgin-2.5.25/arch/i386/kernel/smpboot.c Fri Jul 5 16:42:23 2002
+++ linux-2.5.25-ioremap/arch/i386/kernel/smpboot.c Fri Jul 12 15:55:20 2002
@@ -1019,16 +1019,6 @@
{
int apicid, cpu, bit;
- if (clustered_apic_mode && (numnodes > 1)) {
- printk("Remapping cross-quad port I/O for %d quads\n",
- numnodes);
- printk("xquad_portio vaddr 0x%08lx, len %08lx\n",
- (u_long) xquad_portio,
- (u_long) numnodes * XQUAD_PORTIO_LEN);
- xquad_portio = ioremap (XQUAD_PORTIO_BASE,
- numnodes * XQUAD_PORTIO_LEN);
- }
-
#ifdef CONFIG_MTRR
/* Must be done before other processors booted */
mtrr_init_boot_cpu ();
@@ -1126,6 +1116,16 @@
if (GET_APIC_ID(apic_read(APIC_ID)) != boot_cpu_physical_apicid)
BUG();
+
+ if (clustered_apic_mode && (numnodes > 1)) {
+ printk("Remapping cross-quad port I/O for %d quads\n",
+ numnodes);
+ printk("xquad_portio vaddr 0x%08lx, len %08lx\n",
+ (u_long) xquad_portio,
+ (u_long) numnodes * XQUAD_PORTIO_LEN);
+ xquad_portio = ioremap (XQUAD_PORTIO_BASE,
+ numnodes * XQUAD_PORTIO_LEN);
+ }
/*
* Scan the CPU present map and fire up the other CPUs via do_boot_cpu
-
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This archive was generated by hypermail 2b29 : Mon Jul 15 2002 - 22:00:24 EST