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To trigger the bug: $ bpftool struct_ops register bpf_qdisc_fq.bpf.o /sys/fs/bpf $ echo bpf_fq > /proc/sys/net/core/default_qdisc Fixes: c8240344956e (bpf: net_sched: Support implementation of Qdisc_ops in bpf) Signed-off-by: Amery Hung --- net/sched/sch_api.c | 4 ++-- net/sched/sch_generic.c | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c index db6330258dda..1cda7e7feb32 100644 --- a/net/sched/sch_api.c +++ b/net/sched/sch_api.c @@ -208,7 +208,7 @@ static struct Qdisc_ops *qdisc_lookup_default(const char *name) for (q = qdisc_base; q; q = q->next) { if (!strcmp(name, q->id)) { - if (!try_module_get(q->owner)) + if (!bpf_try_module_get(q, q->owner)) q = NULL; break; } @@ -238,7 +238,7 @@ int qdisc_set_default(const char *name) if (ops) { /* Set new default */ - module_put(default_qdisc_ops->owner); + bpf_module_put(ops, default_qdisc_ops->owner); default_qdisc_ops = ops; } write_unlock(&qdisc_mod_lock); diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index e6fda9f20272..7d2836d66043 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -1002,14 +1002,14 @@ struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue, { struct Qdisc *sch; - if (!try_module_get(ops->owner)) { + if (!bpf_try_module_get(ops, ops->owner)) { NL_SET_ERR_MSG(extack, "Failed to increase module reference counter"); return NULL; } sch = qdisc_alloc(dev_queue, ops, extack); if (IS_ERR(sch)) { - module_put(ops->owner); + bpf_module_put(ops, ops->owner); return NULL; } sch->parent = parentid; -- 2.47.1