On Sunday 22 July 2007 02:49:41 Yinghai Lu wrote: > [PATCH 3/3] x86_64: offset apicid_to_node before use it before > init_cpu_to_node > > When acpi=off or there is no SRAT defined, apicid_to_node is got from K8 > Northbridge PCI configuration space in k8_scan_nodes() in > arch/x86_64/mm/k8toplogy.c. > The problem is that it assumes bsp apic id is 0 at that point. > For four socket system with Quad core cpus installed, all cpus apic id > is offset by 4, and bsp apic id is 4. > For eight socket system with dual core cpus installed, all cpus apic id > is offset by 2, and bsp apic id is 2. > We need offset apicid_to_node array according to boot_cpu_id.--- bsp apic id. > before we use apicid_to_node array. > boot_cpu_id is only valid init_apic_mappings.
<rant> This thing is getting more and more messy. If it gets any more complicated I promise I'll rip out the non ACPI support for quad core NUMA completely and let it require ACPI. Even the people who have a religious problem with ACPI will need to eventually get over it and LinuxBIOS just has to create proper tables, not pile hacks over hacks. It probably was a mistake in the first place to add it. </rant> I don't think you can mess with apicid_to_node[] unconditionally here. e.g. for the ACPI case or for the Intel NUMA case you'll just break everything. What you should do is split init_apic_mappings() up and do a early call that just checks if the CPU has an APIC and maps it using the fixmap and reads boot_cpu_id. Then you can use that information in k8topology.c to create correct tables. -Andi - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
