On Tue, Mar 26, 2019 at 04:55:54PM -0700, Laura Abbott wrote:
> On 1/22/19 7:21 AM, Greg Kroah-Hartman wrote:
> > diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/debugfs-vif.c b/drivers/net/wireless/intel/iwlwifi/mvm/debugfs-vif.c
> > index 33b0af24a537..c52cdc538678 100644
> > --- a/drivers/net/wireless/intel/iwlwifi/mvm/debugfs-vif.c
> > +++ b/drivers/net/wireless/intel/iwlwifi/mvm/debugfs-vif.c
> > @@ -1446,9 +1446,8 @@ static ssize_t iwl_dbgfs_quota_min_read(struct file *file,
> > #define MVM_DEBUGFS_READ_WRITE_FILE_OPS(name, bufsz) \
> > _MVM_DEBUGFS_READ_WRITE_FILE_OPS(name, bufsz, struct ieee80211_vif)
> > #define MVM_DEBUGFS_ADD_FILE_VIF(name, parent, mode) do { \
> > - if (!debugfs_create_file(#name, mode, parent, vif, \
> > - &iwl_dbgfs_##name##_ops)) \
> > - goto err; \
> > + debugfs_create_file(#name, mode, parent, vif, \
> > + &iwl_dbgfs_##name##_ops); \
> > } while (0)
> > MVM_DEBUGFS_READ_FILE_OPS(mac_params);
> > @@ -1483,12 +1482,6 @@ void iwl_mvm_vif_dbgfs_register(struct iwl_mvm *mvm, struct ieee80211_vif *vif)
> > mvmvif->dbgfs_dir = debugfs_create_dir("iwlmvm", dbgfs_dir);
> > - if (!mvmvif->dbgfs_dir) {
> > - IWL_ERR(mvm, "Failed to create debugfs directory under %pd\n",
> > - dbgfs_dir);
> > - return;
> > - }
> > -
> > if (iwlmvm_mod_params.power_scheme != IWL_POWER_SCHEME_CAM &&
> > ((vif->type == NL80211_IFTYPE_STATION && !vif->p2p) ||
> > (vif->type == NL80211_IFTYPE_STATION && vif->p2p)))
> > @@ -1537,12 +1530,6 @@ void iwl_mvm_vif_dbgfs_register(struct iwl_mvm *mvm, struct ieee80211_vif *vif)
> > mvmvif->dbgfs_slink = debugfs_create_symlink(dbgfs_dir->d_name.name,
> > mvm->debugfs_dir, buf);
> > - if (!mvmvif->dbgfs_slink)
> > - IWL_ERR(mvm, "Can't create debugfs symbolic link under %pd\n",
> > - dbgfs_dir);
> > - return;
> > -err:
> > - IWL_ERR(mvm, "Can't create debugfs entity\n");
> > }
>
> Fedora got a bug report https://bugzilla.redhat.com/show_bug.cgi?id=1691034
> of a crash with 5.0 and the user did a bisect which pointed to ff9fb72bc077
> ("debugfs: return error values, not NULL") because the error checking is
> no longer correct in this driver.
>
> Based on https://patchwork.kernel.org/patch/10865839/, it looks like
> this is supposed to go in for 5.2 but this needs to go in now as
> the error checking is currently broken without it. Can this get queued
> for Linus so we can get it in 5.0 stable?
That's odd, I can't see how the error checking is wrong here. If the
directory is not created, an error will be returned, which should be
able to be handled by debugfs_create_file().
So with this patch does the error go away?
strange,
greg k-h
