diff options
| author | Tejun Heo <tj@kernel.org> | 2009-09-29 09:17:56 +0900 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2009-09-29 09:17:56 +0900 |
| commit | ffe0d5a575459ffe664b0762130b557f826fcace (patch) | |
| tree | af581934a717c510a2c6897ca4ed7fcefd440578 /mm/percpu.c | |
| parent | 17d857be649a21ca90008c6dc425d849fa83db5c (diff) | |
| download | lwn-ffe0d5a575459ffe664b0762130b557f826fcace.tar.gz lwn-ffe0d5a575459ffe664b0762130b557f826fcace.zip | |
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 <tj@kernel.org>
Reported-and-tested-by: Tony Vroon <tony@linx.net>
Diffstat (limited to 'mm/percpu.c')
| -rw-r--r-- | mm/percpu.c | 6 |
1 files changed, 3 insertions, 3 deletions
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; |