On Sat, Sep 14, 2024 at 03:58:24PM +0200, Greg Kroah-Hartman wrote:
> On Sat, Sep 14, 2024 at 07:40:31PM +0800, Herbert Xu wrote:
> > On Sat, Sep 14, 2024 at 10:50:33AM +0200, Greg Kroah-Hartman wrote:
> > >
> > > > I think this is still buggy. That if statement should be removed
> > > > as otherwise subsequent calls to debugfs_create_file will provide a
> > > > NULL parent dentry instead of an error parent dentry. This causes
> > > > debugfs to do things differently.
> > >
> > > debugfs, if something goes wrong, will return a real error, never NULL,
> > > so any return value from a call can be passed back in.
> >
> > Right, that's why we should remove the if statement so that the
> > error is saved and can then be passed back into the next debugfs
> > call.
> >
> > With the error-checking if statement there, the error is discarded
> > and the next debugfs call from this driver will simply get a NULL
> > parent dentry.
>
> Sorry, but yes, we are in agreement here, sorry, been reviewing a lot of
> these "clean up" fixes that were wrong and got them confused.
Thanks Herbert and Greg for following up on this.
Here is a fix.
---8<---
The debugfs functions are guaranteed to return a valid error code
instead of NULL upon failure. Consequently, the driver can directly
propagate any error returned without additional checks.
Remove the unnecessary `if` statement after debugfs_create_dir(). If
this function fails, the error code is stored in accel_dev->debugfs_dir
and utilized in subsequent debugfs calls.
Additionally, since accel_dev->debugfs_dir is assured to be non-NULL,
remove the superfluous NULL pointer checks within the adf_dbgfs_add()
and adf_dbgfs_rm().
Fixes: 9260db6640a6 ("crypto: qat - move dbgfs init to separate file")
Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@xxxxxxxxx>
---
drivers/crypto/intel/qat/qat_common/adf_dbgfs.c | 13 +------------
1 file changed, 1 insertion(+), 12 deletions(-)
diff --git a/drivers/crypto/intel/qat/qat_common/adf_dbgfs.c b/drivers/crypto/intel/qat/qat_common/adf_dbgfs.c
index c42f5c25aabd..4c11ad1ebcf0 100644
--- a/drivers/crypto/intel/qat/qat_common/adf_dbgfs.c
+++ b/drivers/crypto/intel/qat/qat_common/adf_dbgfs.c
@@ -22,18 +22,13 @@
void adf_dbgfs_init(struct adf_accel_dev *accel_dev)
{
char name[ADF_DEVICE_NAME_LENGTH];
- void *ret;
/* Create dev top level debugfs entry */
snprintf(name, sizeof(name), "%s%s_%s", ADF_DEVICE_NAME_PREFIX,
accel_dev->hw_device->dev_class->name,
pci_name(accel_dev->accel_pci_dev.pci_dev));
- ret = debugfs_create_dir(name, NULL);
- if (IS_ERR_OR_NULL(ret))
- return;
-
- accel_dev->debugfs_dir = ret;
+ accel_dev->debugfs_dir = debugfs_create_dir(name, NULL);
adf_cfg_dev_dbgfs_add(accel_dev);
}
@@ -59,9 +54,6 @@ EXPORT_SYMBOL_GPL(adf_dbgfs_exit);
*/
void adf_dbgfs_add(struct adf_accel_dev *accel_dev)
{
- if (!accel_dev->debugfs_dir)
- return;
-
if (!accel_dev->is_vf) {
adf_fw_counters_dbgfs_add(accel_dev);
adf_heartbeat_dbgfs_add(accel_dev);
@@ -77,9 +69,6 @@ void adf_dbgfs_add(struct adf_accel_dev *accel_dev)
*/
void adf_dbgfs_rm(struct adf_accel_dev *accel_dev)
{
- if (!accel_dev->debugfs_dir)
- return;
-
if (!accel_dev->is_vf) {
adf_tl_dbgfs_rm(accel_dev);
adf_cnv_dbgfs_rm(accel_dev);
--
2.46.0
