drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c:366 mlx5_devcom_get_next_peer_data() error: uninitialized symbol 'data'.

drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c:366 mlx5_devcom_get_next_peer_data() error: uninitialized symbol 'data'.

[kernel test robot]

BCC: lkp@intel.com
CC: oe-kbuild-all@lists.linux.dev
CC: linux-kernel@vger.kernel.org
TO: Wei Yang <richard.weiyang@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Linux Memory Management List <linux-mm@kvack.org>

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   f3ddc438a29f78f0642bfcf84407c236a0b2bdc7
commit: 2932fb0a927d30690b8cb70c71d511fd9054bb61 list: leverage list_is_head() for list_entry_is_head()
date:   10 months ago
:::::: branch date: 4 hours ago
:::::: commit date: 10 months ago
config: openrisc-randconfig-r072-20241206 (https://download.01.org/0day-ci/archive/20241207/202412070931.gIXUE178-lkp@intel.com/config)
compiler: or1k-linux-gcc (GCC) 14.2.0

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Reported-by: Dan Carpenter <error27@gmail.com>
| Closes: https://lore.kernel.org/r/202412070931.gIXUE178-lkp@intel.com/

smatch warnings:
drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c:366 mlx5_devcom_get_next_peer_data() error: uninitialized symbol 'data'.
drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c:395 mlx5_devcom_get_next_peer_data_rcu() error: uninitialized symbol 'data'.

vim +/data +366 drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c

691c041bf20899f Vlad Buslov    2023-03-31  344  
88d162b479815f5 Roi Dayan      2023-05-04  345  void *mlx5_devcom_get_next_peer_data(struct mlx5_devcom_comp_dev *devcom,
88d162b479815f5 Roi Dayan      2023-05-04  346  				     struct mlx5_devcom_comp_dev **pos)
691c041bf20899f Vlad Buslov    2023-03-31  347  {
88d162b479815f5 Roi Dayan      2023-05-04  348  	struct mlx5_devcom_comp *comp = devcom->comp;
88d162b479815f5 Roi Dayan      2023-05-04  349  	struct mlx5_devcom_comp_dev *tmp;
88d162b479815f5 Roi Dayan      2023-05-04  350  	void *data;
691c041bf20899f Vlad Buslov    2023-03-31  351  
88d162b479815f5 Roi Dayan      2023-05-04  352  	tmp = list_prepare_entry(*pos, &comp->comp_dev_list_head, list);
691c041bf20899f Vlad Buslov    2023-03-31  353  
88d162b479815f5 Roi Dayan      2023-05-04  354  	list_for_each_entry_continue(tmp, &comp->comp_dev_list_head, list) {
88d162b479815f5 Roi Dayan      2023-05-04  355  		if (tmp != devcom) {
88d162b479815f5 Roi Dayan      2023-05-04  356  			data = rcu_dereference_protected(tmp->data, lockdep_is_held(&comp->sem));
88d162b479815f5 Roi Dayan      2023-05-04  357  			if (data)
691c041bf20899f Vlad Buslov    2023-03-31  358  				break;
90ca127c62e9963 Saeed Mahameed 2023-06-02  359  		}
90ca127c62e9963 Saeed Mahameed 2023-06-02  360  	}
90ca127c62e9963 Saeed Mahameed 2023-06-02  361  
88d162b479815f5 Roi Dayan      2023-05-04  362  	if (list_entry_is_head(tmp, &comp->comp_dev_list_head, list))
90ca127c62e9963 Saeed Mahameed 2023-06-02  363  		return NULL;
90ca127c62e9963 Saeed Mahameed 2023-06-02  364  
88d162b479815f5 Roi Dayan      2023-05-04  365  	*pos = tmp;
88d162b479815f5 Roi Dayan      2023-05-04 @366  	return data;
90ca127c62e9963 Saeed Mahameed 2023-06-02  367  }
90ca127c62e9963 Saeed Mahameed 2023-06-02  368  
88d162b479815f5 Roi Dayan      2023-05-04  369  void *mlx5_devcom_get_next_peer_data_rcu(struct mlx5_devcom_comp_dev *devcom,
88d162b479815f5 Roi Dayan      2023-05-04  370  					 struct mlx5_devcom_comp_dev **pos)
90ca127c62e9963 Saeed Mahameed 2023-06-02  371  {
88d162b479815f5 Roi Dayan      2023-05-04  372  	struct mlx5_devcom_comp *comp = devcom->comp;
88d162b479815f5 Roi Dayan      2023-05-04  373  	struct mlx5_devcom_comp_dev *tmp;
88d162b479815f5 Roi Dayan      2023-05-04  374  	void *data;
691c041bf20899f Vlad Buslov    2023-03-31  375  
88d162b479815f5 Roi Dayan      2023-05-04  376  	tmp = list_prepare_entry(*pos, &comp->comp_dev_list_head, list);
90ca127c62e9963 Saeed Mahameed 2023-06-02  377  
88d162b479815f5 Roi Dayan      2023-05-04  378  	list_for_each_entry_continue(tmp, &comp->comp_dev_list_head, list) {
88d162b479815f5 Roi Dayan      2023-05-04  379  		if (tmp != devcom) {
691c041bf20899f Vlad Buslov    2023-03-31  380  			/* This can change concurrently, however 'data' pointer will remain
691c041bf20899f Vlad Buslov    2023-03-31  381  			 * valid for the duration of RCU read section.
691c041bf20899f Vlad Buslov    2023-03-31  382  			 */
e67f928a5204cc5 Shay Drory     2023-02-07  383  			if (!READ_ONCE(comp->ready))
691c041bf20899f Vlad Buslov    2023-03-31  384  				return NULL;
88d162b479815f5 Roi Dayan      2023-05-04  385  			data = rcu_dereference(tmp->data);
88d162b479815f5 Roi Dayan      2023-05-04  386  			if (data)
90ca127c62e9963 Saeed Mahameed 2023-06-02  387  				break;
90ca127c62e9963 Saeed Mahameed 2023-06-02  388  		}
fadd59fc50d0101 Aviv Heller    2018-12-04  389  	}
fadd59fc50d0101 Aviv Heller    2018-12-04  390  
88d162b479815f5 Roi Dayan      2023-05-04  391  	if (list_entry_is_head(tmp, &comp->comp_dev_list_head, list))
90ca127c62e9963 Saeed Mahameed 2023-06-02  392  		return NULL;
fadd59fc50d0101 Aviv Heller    2018-12-04  393  
88d162b479815f5 Roi Dayan      2023-05-04  394  	*pos = tmp;
88d162b479815f5 Roi Dayan      2023-05-04 @395  	return data;
fadd59fc50d0101 Aviv Heller    2018-12-04  396  }
e534552c92a4469 Shay Drory     2023-10-12  397  

:::::: The code at line 366 was first introduced by commit
:::::: 88d162b479815f5d6b6a4ff5fdb07aec9dc6280c net/mlx5: Devcom, Infrastructure changes

:::::: TO: Roi Dayan <roid@nvidia.com>
:::::: CC: Saeed Mahameed <saeedm@nvidia.com>

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