From 078a198906c796981f93ff100c210506e91aade5 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 4 Mar 2011 16:32:02 +0100 Subject: [PATCH] x86-64, NUMA: Don't assume phys node 0 is always online in numa_emulation() Undetermined entries in emu_nid_to_phys[] are filled with zero assuming that physical node 0 is always online; however, this might not be true depending on hardware configuration. Find a physical node which is actually online and use it instead. Signed-off-by: Tejun Heo Reported-by: David Rientjes LKML-Reference: --- arch/x86/mm/numa_emulation.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/arch/x86/mm/numa_emulation.c b/arch/x86/mm/numa_emulation.c index 75b31dc0f329..3696be0c2204 100644 --- a/arch/x86/mm/numa_emulation.c +++ b/arch/x86/mm/numa_emulation.c @@ -301,6 +301,7 @@ void __init numa_emulation(struct numa_meminfo *numa_meminfo, int numa_dist_cnt) const u64 max_addr = max_pfn << PAGE_SHIFT; u8 *phys_dist = NULL; size_t phys_size = numa_dist_cnt * numa_dist_cnt * sizeof(phys_dist[0]); + int dfl_phys_nid; int i, j, ret; if (!emu_cmdline) @@ -357,6 +358,19 @@ void __init numa_emulation(struct numa_meminfo *numa_meminfo, int numa_dist_cnt) node_distance(i, j); } + /* determine the default phys nid to use for unmapped nodes */ + dfl_phys_nid = NUMA_NO_NODE; + for (i = 0; i < ARRAY_SIZE(emu_nid_to_phys); i++) { + if (emu_nid_to_phys[i] != NUMA_NO_NODE) { + dfl_phys_nid = emu_nid_to_phys[i]; + break; + } + } + if (dfl_phys_nid == NUMA_NO_NODE) { + pr_warning("NUMA: Warning: can't determine default physical node, disabling emulation\n"); + goto no_emu; + } + /* commit */ *numa_meminfo = ei; @@ -377,7 +391,7 @@ void __init numa_emulation(struct numa_meminfo *numa_meminfo, int numa_dist_cnt) /* make sure all emulated nodes are mapped to a physical node */ for (i = 0; i < ARRAY_SIZE(emu_nid_to_phys); i++) if (emu_nid_to_phys[i] == NUMA_NO_NODE) - emu_nid_to_phys[i] = 0; + emu_nid_to_phys[i] = dfl_phys_nid; /* * Transform distance table. numa_set_distance() ignores all -- 2.11.0