[PATCH AUTOSEL 5.6 056/606] clk: Unlink clock if failed to prepare or enable

[Sasha Levin]

From: Marc Zyngier <maz@xxxxxxxxxx>

commit 018d4671b9bbd4a5c55cf6eab3e1dbc70a50b66e upstream.

On failing to prepare or enable a clock, remove the core structure
from the list it has been inserted as it is about to be freed.

This otherwise leads to random crashes when subsequent clocks get
registered, during which parsing of the clock tree becomes adventurous.

Observed with QEMU's RPi-3 emulation.

Fixes: 12ead77432f2 ("clk: Don't try to enable critical clocks if prepare failed")
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
Cc: Guenter Roeck <linux@xxxxxxxxxxxx>
Cc: Stephen Boyd <sboyd@xxxxxxxxxx>
Cc: Michael Turquette <mturquette@xxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/20200505140953.409430-1-maz@xxxxxxxxxx
Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/clk/clk.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 305544b68b8a..f22b7aed6e64 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -3512,6 +3512,9 @@ static int __clk_core_init(struct clk_core *core)
 out:
 	clk_pm_runtime_put(core);
 unlock:
+	if (ret)
+		hlist_del_init(&core->child_node);
+
 	clk_prepare_unlock();
 
 	if (!ret)
-- 
2.25.1