[PATCH 07/11] firmware: arm_scmi: Harden clock parents discovery
From: Cristian Marussi <cristian.marussi@arm.com>
Date: 2026-02-27 15:33:49
Also in:
arm-scmi, linux-clk, linux-renesas-soc, lkml
Subsystem:
system control & power/management interface (scpi/scmi) message protocol drivers, the rest · Maintainers:
Sudeep Holla, Linus Torvalds
Fix clock parents enumeration to account only for effectively discovered parents during enumeration, avoiding to trust the total number of parents declared upfront by the platform. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> --- drivers/firmware/arm_scmi/clock.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-)
diff --git a/drivers/firmware/arm_scmi/clock.c b/drivers/firmware/arm_scmi/clock.c
index d0fb5affb5cf..15faa79abed4 100644
--- a/drivers/firmware/arm_scmi/clock.c
+++ b/drivers/firmware/arm_scmi/clock.c@@ -270,15 +270,15 @@ static int iter_clk_possible_parents_update_state(struct scmi_iterator_state *st * assume it's returned+remaining on first call. */ if (!st->max_resources) { - p->clkd->info.num_parents = st->num_returned + st->num_remaining; - p->clkd->info.parents = devm_kcalloc(p->dev, - p->clkd->info.num_parents, + int num_parents = st->num_returned + st->num_remaining; + + p->clkd->info.parents = devm_kcalloc(p->dev, num_parents, sizeof(*p->clkd->info.parents), GFP_KERNEL); - if (!p->clkd->info.parents) { - p->clkd->info.num_parents = 0; + if (!p->clkd->info.parents) return -ENOMEM; - } + + /* max_resources is used by the iterators to control bounds */ st->max_resources = st->num_returned + st->num_remaining; }
@@ -293,9 +293,11 @@ static int iter_clk_possible_parents_process_response(const struct scmi_protocol const struct scmi_msg_resp_clock_possible_parents *r = response; struct scmi_clk_ipriv *p = priv; - u32 *parent = &p->clkd->info.parents[st->desc_index + st->loop_idx]; + p->clkd->info.parents[st->desc_index + st->loop_idx] = + le32_to_cpu(r->possible_parents[st->loop_idx]); - *parent = le32_to_cpu(r->possible_parents[st->loop_idx]); + /* Count only effectively discovered parents */ + p->clkd->info.num_parents++; return 0; }
--
2.53.0