[PATCH v13 net-next 03/11] dpll: fix stale iteration in dpll_pin_on_pin_unregister()
From: Grzegorz Nitka
Date: Fri Jun 05 2026 - 11:32:05 EST
Neither parent->dpll_refs nor pin->dpll_refs on its own is a correct
iteration target at unregister time:
- pin->dpll_refs includes DPLLs the child was registered against
via a different parent or directly; blind unregister WARNs on
the cookie miss in dpll_xa_ref_pin_del().
- parent->dpll_refs reflects the parent's current attachments, not
those at child-register time. Another driver may have (un)reg'd
the parent against additional DPLLs in the meantime, so we miss
registrations that exist and visit DPLLs that have none.
Walk pin->dpll_refs and use dpll_pin_registration_find() to filter
to entries whose cookie is this parent. Symmetric with
dpll_pin_on_pin_register(), correct under any subsequent change to
parent->dpll_refs.
Fixes: 9431063ad323 ("dpll: core: Add DPLL framework base functions")
Signed-off-by: Grzegorz Nitka <grzegorz.nitka@xxxxxxxxx>
---
drivers/dpll/dpll_core.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/dpll/dpll_core.c b/drivers/dpll/dpll_core.c
index 6dc7e93ece75..cea7e2be2cbc 100644
--- a/drivers/dpll/dpll_core.c
+++ b/drivers/dpll/dpll_core.c
@@ -1031,14 +1031,19 @@ EXPORT_SYMBOL_GPL(dpll_pin_on_pin_register);
void dpll_pin_on_pin_unregister(struct dpll_pin *parent, struct dpll_pin *pin,
const struct dpll_pin_ops *ops, void *priv)
{
+ struct dpll_pin_registration *reg;
struct dpll_pin_ref *ref;
unsigned long i;
mutex_lock(&dpll_lock);
dpll_pin_delete_ntf(pin);
dpll_xa_ref_pin_del(&pin->parent_refs, parent, ops, priv, pin);
- xa_for_each(&pin->dpll_refs, i, ref)
+ xa_for_each(&pin->dpll_refs, i, ref) {
+ reg = dpll_pin_registration_find(ref, ops, priv, parent);
+ if (!reg)
+ continue;
__dpll_pin_unregister(ref->dpll, pin, ops, priv, parent);
+ }
mutex_unlock(&dpll_lock);
}
EXPORT_SYMBOL_GPL(dpll_pin_on_pin_unregister);
--
2.39.3