[PATCH] firewire: core: revert GFP_ATOMIC changes

From: Dan Carpenter
Date: Mon Jul 17 2023 - 05:50:49 EST


This was recently changed from GFP_ATOMIC to GFP_KERNEL, but Smatch
complains that GFP_ATOMIC is still required:

drivers/firewire/core-topology.c:223 build_tree() warn: sleeping in atomic context

The problematic call trees are:

fw_core_handle_bus_reset() <- spin_lock_irqsave(&card->lock, flags);
-> build_tree()
-> fw_node_create() <- sleeping allocation

fw_core_handle_bus_reset() <- spin_lock_irqsave(&card->lock, flags);
-> update_tree()
-> fw_node_event()

This second call tree is a bit complicated because we event is not
FW_NODE_CREATED so we would have to hit a goto create; to hit the
bug.

Fixes: 06f45435d985 ("firewire: core: obsolete usage of GFP_ATOMIC at building node tree")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
>From static analysis. Smatch does not warn about fw_node_event()
because event can't be FW_NODE_CREATED.

drivers/firewire/core-device.c | 2 +-
drivers/firewire/core-topology.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/firewire/core-device.c b/drivers/firewire/core-device.c
index a3104e35412c..aa597cda0d88 100644
--- a/drivers/firewire/core-device.c
+++ b/drivers/firewire/core-device.c
@@ -1211,7 +1211,7 @@ void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
* without actually having a link.
*/
create:
- device = kzalloc(sizeof(*device), GFP_KERNEL);
+ device = kzalloc(sizeof(*device), GFP_ATOMIC);
if (device == NULL)
break;

diff --git a/drivers/firewire/core-topology.c b/drivers/firewire/core-topology.c
index 88466b663482..f40c81534381 100644
--- a/drivers/firewire/core-topology.c
+++ b/drivers/firewire/core-topology.c
@@ -101,7 +101,7 @@ static struct fw_node *fw_node_create(u32 sid, int port_count, int color)
{
struct fw_node *node;

- node = kzalloc(struct_size(node, ports, port_count), GFP_KERNEL);
+ node = kzalloc(struct_size(node, ports, port_count), GFP_ATOMIC);
if (node == NULL)
return NULL;

--
2.39.2