Gabor Gombas wrote: > Hi, > > On Sat, Jan 05, 2008 at 07:50:39AM +0000, Al Viro wrote: > >> Could you stick >> if (!parent->d_inode) >> printk(KERN_WARNING "sysfs locking blows: %s", >> parent->d_name.name); >> right before >> mutex_lock(&parent->d_inode->i_mutex); >> dentry = lookup_one_noperm(cur->s_name, parent); >> mutex_unlock(&parent->d_inode->i_mutex); >> in sysfs_get_dentry() (fs/sysfs/dir.c) and verify that it does, indeed, >> trigger? > > Here it is: > > Jan 7 14:35:43 twister kernel: sysfs locking blows: acl001BAFE1624D<1>Unable > to handle kernel NULL pointer dereference at 00000000000000b8 RIP:
Does the attached patch fix the problem? -- tejun
diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 3371629..4e7f3bf 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -878,7 +878,6 @@ again: error = 0; d_add(new_dentry, NULL); d_move(old_dentry, new_dentry); - dput(new_dentry); /* Remove from old parent's list and insert into new parent's list. */ sysfs_unlink_sibling(sd);
