From: Daniel Yeisley Date: Tue, 30 May 2006 20:47:57 +0000 (+0200) Subject: [PATCH] x86_64: Handle empty node zero X-Git-Tag: v2.6.17-rc6~77 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0d01532451710110a93891ae152d1dd1ee006ccf;p=linux-2.6 [PATCH] x86_64: Handle empty node zero From: Daniel Yeisley It is possible to boot a Unisys ES7000 with CPUs from multiple cells, and not also include the memory from those cells. This can create a scenario where node 0 has cpus, but no associated memory. The system will boot fine in a configuration where node 0 has memory, but nodes 2 and 3 do not. [AK: I rechecked the code and generic code seems to indeed handle that already. Dan's original patch had a change for mm/slab.c that seems to be already in now.] Signed-off-by: Andi Kleen Signed-off-by: Linus Torvalds --- diff --git a/arch/x86_64/kernel/pci-dma.c b/arch/x86_64/kernel/pci-dma.c index af035ede70..a9275c9557 100644 --- a/arch/x86_64/kernel/pci-dma.c +++ b/arch/x86_64/kernel/pci-dma.c @@ -54,6 +54,10 @@ dma_alloc_pages(struct device *dev, gfp_t gfp, unsigned order) else #endif node = numa_node_id(); + + if (node < first_node(node_online_map)) + node = first_node(node_online_map); + page = alloc_pages_node(node, gfp, order); return page ? page_address(page) : NULL; } diff --git a/arch/x86_64/kernel/setup.c b/arch/x86_64/kernel/setup.c index f0870bef24..655b9192ee 100644 --- a/arch/x86_64/kernel/setup.c +++ b/arch/x86_64/kernel/setup.c @@ -1051,7 +1051,7 @@ static void srat_detect_node(void) for now. */ node = apicid_to_node[hard_smp_processor_id()]; if (node == NUMA_NO_NODE) - node = 0; + node = first_node(node_online_map); numa_set_node(cpu, node); if (acpi_numa > 0) diff --git a/arch/x86_64/mm/srat.c b/arch/x86_64/mm/srat.c index e1513532df..474df22c6e 100644 --- a/arch/x86_64/mm/srat.c +++ b/arch/x86_64/mm/srat.c @@ -399,8 +399,10 @@ int __init acpi_scan_nodes(unsigned long start, unsigned long end) /* First clean up the node list */ for (i = 0; i < MAX_NUMNODES; i++) { cutoff_node(i, start, end); - if ((nodes[i].end - nodes[i].start) < NODE_MIN_SIZE) + if ((nodes[i].end - nodes[i].start) < NODE_MIN_SIZE) { unparse_node(i); + node_set_offline(i); + } } if (acpi_numa <= 0)