From: Yuan Can yuancan@huawei.com
[ Upstream commit 4c3c796aca02883ad35bb117468938cc4022ca41 ]
A problem about ntb_hw_intel create debugfs failed is triggered with the following log given:
[ 273.112733] Intel(R) PCI-E Non-Transparent Bridge Driver 2.0 [ 273.115342] debugfs: Directory 'ntb_hw_intel' with parent '/' already present!
The reason is that intel_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_intel can never be created later.
intel_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: e26a5843f7f5 ("NTB: Split ntb_hw_intel and ntb_transport drivers") Signed-off-by: Yuan Can yuancan@huawei.com Acked-by: Dave Jiang dave.jiang@intel.com Signed-off-by: Jon Mason jdmason@kudzu.us Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/ntb/hw/intel/ntb_hw_gen1.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/ntb/hw/intel/ntb_hw_gen1.c b/drivers/ntb/hw/intel/ntb_hw_gen1.c index bb57ec2390299..8d8739bff9f3c 100644 --- a/drivers/ntb/hw/intel/ntb_hw_gen1.c +++ b/drivers/ntb/hw/intel/ntb_hw_gen1.c @@ -2065,12 +2065,17 @@ static struct pci_driver intel_ntb_pci_driver = {
static int __init intel_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(&intel_ntb_pci_driver); + ret = pci_register_driver(&intel_ntb_pci_driver); + if (ret) + debugfs_remove_recursive(debugfs_dir); + + return ret; } module_init(intel_ntb_pci_driver_init);