[PATCH v2 1/3] clk: xilinx: vcu: unregister pll_post only if registered correctly

Rohit Visavalia rohit.visavalia at amd.com
Thu Jan 2 09:03:57 PST 2025


If registration of pll_post is failed, it will be set to NULL or ERR,
unregistering same will fail with following call trace:

Unable to handle kernel NULL pointer dereference at virtual address 008
pc : clk_hw_unregister+0xc/0x20
lr : clk_hw_unregister_fixed_factor+0x18/0x30
sp : ffff800011923850
...
Call trace:
 clk_hw_unregister+0xc/0x20
 clk_hw_unregister_fixed_factor+0x18/0x30
 xvcu_unregister_clock_provider+0xcc/0xf4 [xlnx_vcu]
 xvcu_probe+0x2bc/0x53c [xlnx_vcu]

Fixes: 4472e1849db7 ("soc: xilinx: vcu: make pll post divider explicit")
Signed-off-by: Rohit Visavalia <rohit.visavalia at amd.com>
---
Changes in v2:
  - Changed patches sequence to have patches with "Fixes" as preceding in order
  - Added Fixes tag
  - Link to v1: https://lore.kernel.org/linux-clk/20241226122023.3439559-4-rohit.visavalia@amd.com 

---
 drivers/clk/xilinx/xlnx_vcu.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/xilinx/xlnx_vcu.c b/drivers/clk/xilinx/xlnx_vcu.c
index 81501b48412e..88b3fd8250c2 100644
--- a/drivers/clk/xilinx/xlnx_vcu.c
+++ b/drivers/clk/xilinx/xlnx_vcu.c
@@ -587,8 +587,8 @@ static void xvcu_unregister_clock_provider(struct xvcu_device *xvcu)
 		xvcu_clk_hw_unregister_leaf(hws[CLK_XVCU_ENC_MCU]);
 	if (!IS_ERR_OR_NULL(hws[CLK_XVCU_ENC_CORE]))
 		xvcu_clk_hw_unregister_leaf(hws[CLK_XVCU_ENC_CORE]);
-
-	clk_hw_unregister_fixed_factor(xvcu->pll_post);
+	if (!IS_ERR_OR_NULL(xvcu->pll_post))
+		clk_hw_unregister_fixed_factor(xvcu->pll_post);
 }
 
 /**
-- 
2.25.1




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