A problem about ntb_hw_amd create debugfs failed is triggered with the
following log given:
[ 618.431232] AMD(R) PCI-E Non-Transparent Bridge Driver 1.0
[ 618.433284] debugfs: Directory 'ntb_hw_amd' with parent '/' already present!
The reason is that amd_ntb_pci_driver_init() returns pci_register_driver()
directly without checking its return value, if pci_register_driver()
failed, it returns without destroy the newly created debugfs, resulting
the debugfs of ntb_hw_amd can never be created later.
amd_ntb_pci_driver_init()
debugfs_create_dir() # create debugfs directory
pci_register_driver()
driver_register()
bus_add_driver()
priv = kzalloc(...) # OOM happened
# return without destroy debugfs directory
Fix by removing debugfs when pci_register_driver() returns error.
Fixes: a1b3695820aa ("NTB: Add support for AMD PCI-Express Non-Transparent Bridge")
Signed-off-by: Yuan Can <yuancan@huawei.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
static int __init amd_ntb_pci_driver_init(void)
{
+ int ret;
pr_info("%s %s\n", NTB_DESC, NTB_VER);
if (debugfs_initialized())
debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL);
- return pci_register_driver(&amd_ntb_pci_driver);
+ ret = pci_register_driver(&amd_ntb_pci_driver);
+ if (ret)
+ debugfs_remove_recursive(debugfs_dir);
+
+ return ret;
}
module_init(amd_ntb_pci_driver_init);