6.15-stable review patch. If anyone has any objections, please let me know.
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From: Sascha Hauer s.hauer@pengutronix.de
commit 6306e0c5a0d28e9df2b5902f4a021204bee75173 upstream.
The SCMI clock driver currently assumes that parent clocks are always initialized before their children. However, this assumption can fail if a child clock is encountered before its parent during probe.
This leads to an issue during initialization of the parent_data array:
sclk->parent_data[i].hw = hws[sclk->info->parents[i]];
If the parent clock's hardware structure has not been initialized yet, this assignment results in invalid data.
To resolve this, allocate all struct scmi_clk instances as a contiguous array at the beginning of the probe and populate the hws[] array upfront. This ensures that any parent referenced later is already initialized, regardless of the order in which clocks are processed.
Note that we can no longer free individual scmi_clk instances if scmi_clk_ops_init() fails which shouldn't be a problem if the SCMI platform has proper per-agent clock discovery.
Fixes: 65a8a3dd3b95f ("clk: scmi: Add support for clock {set,get}_parent") Reviewed-by: peng.fan@nxp.com Reviewed-by: Cristian Marussi cristian.marussi@arm.com Reviewed-by: Sudeep Holla sudeep.holla@arm.com Signed-off-by: Sascha Hauer s.hauer@pengutronix.de Link: https://lore.kernel.org/r/20250612-clk-scmi-children-parent-fix-v3-1-7de52a2... Signed-off-by: Stephen Boyd sboyd@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/clk/clk-scmi.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-)
--- a/drivers/clk/clk-scmi.c +++ b/drivers/clk/clk-scmi.c @@ -404,6 +404,7 @@ static int scmi_clocks_probe(struct scmi const struct scmi_handle *handle = sdev->handle; struct scmi_protocol_handle *ph; const struct clk_ops *scmi_clk_ops_db[SCMI_MAX_CLK_OPS] = {}; + struct scmi_clk *sclks;
if (!handle) return -ENODEV; @@ -430,18 +431,21 @@ static int scmi_clocks_probe(struct scmi transport_is_atomic = handle->is_transport_atomic(handle, &atomic_threshold_us);
+ sclks = devm_kcalloc(dev, count, sizeof(*sclks), GFP_KERNEL); + if (!sclks) + return -ENOMEM; + + for (idx = 0; idx < count; idx++) + hws[idx] = &sclks[idx].hw; + for (idx = 0; idx < count; idx++) { - struct scmi_clk *sclk; + struct scmi_clk *sclk = &sclks[idx]; const struct clk_ops *scmi_ops;
- sclk = devm_kzalloc(dev, sizeof(*sclk), GFP_KERNEL); - if (!sclk) - return -ENOMEM; - sclk->info = scmi_proto_clk_ops->info_get(ph, idx); if (!sclk->info) { dev_dbg(dev, "invalid clock info for idx %d\n", idx); - devm_kfree(dev, sclk); + hws[idx] = NULL; continue; }
@@ -479,13 +483,11 @@ static int scmi_clocks_probe(struct scmi if (err) { dev_err(dev, "failed to register clock %d\n", idx); devm_kfree(dev, sclk->parent_data); - devm_kfree(dev, sclk); hws[idx] = NULL; } else { dev_dbg(dev, "Registered clock:%s%s\n", sclk->info->name, scmi_ops->enable ? " (atomic ops)" : ""); - hws[idx] = &sclk->hw; } }