[PATCH] of/platform: increase refcount of fwnode

From: Peng Fan (OSS)
Date: Sat Aug 12 2023 - 08:19:34 EST


From: Peng Fan <peng.fan@xxxxxxx>

commit 0f8e5651095b
("of/platform: Propagate firmware node by calling device_set_node()")
use of_fwnode_handle to replace of_node_get, which introduces a side
effect that the refcount is not increased. Then the out of tree
jailhouse hypervisor enable/disable test will trigger kernel dump in
of_overlay_remove, with the following sequence
"
of_changeset_revert(&overlay_changeset);
of_changeset_destroy(&overlay_changeset);
of_overlay_remove(&overlay_id);
"

So increase the refcount to avoid issues.

Fixes: 0f8e5651095b ("of/platform: Propagate firmware node by calling device_set_node()")
Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
---
drivers/of/platform.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 0c3475e7d2ff..4659ff5a79c8 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -113,6 +113,7 @@ struct platform_device *of_device_alloc(struct device_node *np,
const char *bus_id,
struct device *parent)
{
+ struct fwnode_handle *fwnode = of_fwnode_handle(np);
struct platform_device *dev;
int rc, i, num_reg = 0;
struct resource *res;
@@ -141,7 +142,7 @@ struct platform_device *of_device_alloc(struct device_node *np,
}

/* setup generic device info */
- device_set_node(&dev->dev, of_fwnode_handle(np));
+ device_set_node(&dev->dev, fwnode_handle_get(fwnode));
dev->dev.parent = parent ? : &platform_bus;

if (bus_id)
@@ -221,6 +222,7 @@ static struct amba_device *of_amba_device_create(struct device_node *node,
void *platform_data,
struct device *parent)
{
+ struct fwnode_handle *fwnode = of_fwnode_handle(node);
struct amba_device *dev;
int ret;

@@ -239,7 +241,7 @@ static struct amba_device *of_amba_device_create(struct device_node *node,
dev->dev.dma_mask = &dev->dev.coherent_dma_mask;

/* setup generic device info */
- device_set_node(&dev->dev, of_fwnode_handle(node));
+ device_set_node(&dev->dev, fwnode_handle_get(fwnode));
dev->dev.parent = parent ? : &platform_bus;
dev->dev.platform_data = platform_data;
if (bus_id)
--
2.37.1