path: root/kernel
diff options
authorMathias Krause <minipli@googlemail.com>2017-09-08 20:57:09 +0200
committerHerbert Xu <herbert@gondor.apana.org.au>2017-10-07 12:10:31 +0800
commit1bd845bcb41d5b7f83745e0cb99273eb376f2ec5 (patch)
treef0f49135d882c6c0d3313587eaf657d7fc926c54 /kernel
parent5e1a646204deb0efd0e0bbc1730ac11dcb39f8fb (diff)
padata: set cpu_index of unused CPUs to -1
The parallel queue per-cpu data structure gets initialized only for CPUs in the 'pcpu' CPU mask set. This is not sufficient as the reorder timer may run on a different CPU and might wrongly decide it's the target CPU for the next reorder item as per-cpu memory gets memset(0) and we might be waiting for the first CPU in cpumask.pcpu, i.e. cpu_index 0. Make the '__this_cpu_read(pd->pqueue->cpu_index) == next_queue->cpu_index' compare in padata_get_next() fail in this case by initializing the cpu_index member of all per-cpu parallel queues. Use -1 for unused ones. Signed-off-by: Mathias Krause <minipli@googlemail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'kernel')
1 files changed, 7 insertions, 1 deletions
diff --git a/kernel/padata.c b/kernel/padata.c
index 868f947166d7..1b9b4bac4a9b 100644
--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -384,8 +384,14 @@ static void padata_init_pqueues(struct parallel_data *pd)
struct padata_parallel_queue *pqueue;
cpu_index = 0;
- for_each_cpu(cpu, pd->cpumask.pcpu) {
+ for_each_possible_cpu(cpu) {
pqueue = per_cpu_ptr(pd->pqueue, cpu);
+ if (!cpumask_test_cpu(cpu, pd->cpumask.pcpu)) {
+ pqueue->cpu_index = -1;
+ continue;
+ }
pqueue->pd = pd;
pqueue->cpu_index = cpu_index;