From ffe0d5a575459ffe664b0762130b557f826fcace Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 29 Sep 2009 09:17:56 +0900 Subject: percpu: fix unit_map[] verification in pcpu_setup_first_chunk() pcpu_setup_first_chunk() incorrectly used NR_CPUS as the impossible unit number while unit number can equal and go over NR_CPUS with sparse unit map. This triggers BUG_ON() spuriously on machines which have non-power-of-two number of cpus. Use UINT_MAX instead. Signed-off-by: Tejun Heo Reported-and-tested-by: Tony Vroon --- mm/percpu.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'mm') diff --git a/mm/percpu.c b/mm/percpu.c index 43d8cacfdaa5..e5c4cbda6026 100644 --- a/mm/percpu.c +++ b/mm/percpu.c @@ -1604,7 +1604,7 @@ int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai, unit_off = alloc_bootmem(nr_cpu_ids * sizeof(unit_off[0])); for (cpu = 0; cpu < nr_cpu_ids; cpu++) - unit_map[cpu] = NR_CPUS; + unit_map[cpu] = UINT_MAX; pcpu_first_unit_cpu = NR_CPUS; for (group = 0, unit = 0; group < ai->nr_groups; group++, unit += i) { @@ -1619,7 +1619,7 @@ int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai, continue; BUG_ON(cpu > nr_cpu_ids || !cpu_possible(cpu)); - BUG_ON(unit_map[cpu] != NR_CPUS); + BUG_ON(unit_map[cpu] != UINT_MAX); unit_map[cpu] = unit + i; unit_off[cpu] = gi->base_offset + i * ai->unit_size; @@ -1632,7 +1632,7 @@ int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai, pcpu_nr_units = unit; for_each_possible_cpu(cpu) - BUG_ON(unit_map[cpu] == NR_CPUS); + BUG_ON(unit_map[cpu] == UINT_MAX); pcpu_nr_groups = ai->nr_groups; pcpu_group_offsets = group_offsets; -- cgit v1.2.3