Re: linux-2.6.23-git3: Many sysfs-related warnings in dmesg

[Greg KH <greg@kroah.com>]

On Tue, Oct 16, 2007 at 11:13:19PM +0200, Rafael J. Wysocki wrote:
> On Tuesday, 16 October 2007 22:50, Jens Axboe wrote:
> > On Tue, Oct 16 2007, Greg KH wrote:
> > > On Tue, Oct 16, 2007 at 10:04:51PM +0200, Rafael J. Wysocki wrote:
> > > > On Tuesday, 16 October 2007 06:50, Greg KH wrote:
> > > > > On Sat, Oct 13, 2007 at 09:26:32PM +0200, Rafael J. Wysocki wrote:
> > > > > > Hi,
> > > > > > 
> > > > > > There are many traces like this in my dmesg from 2.6.23-git3 (they don't
> > > > > > appear for vanilla 2.6.23):
> > > > > > 
> > > > > > <4>sysfs: duplicate filename 'ethxx1' can not be created
> > > > > > WARNING: at /home/rafael/src/linux-2.6/fs/sysfs/dir.c:425 sysfs_add_one()
> > > > > > 
> > > > > > Call Trace:
> > > > > >  [<ffffffff802d1532>] sysfs_add_one+0x5c/0xc9
> > > > > >  [<ffffffff802d2411>] sysfs_create_link+0xd1/0x12c
> > > > > >  [<ffffffff803756da>] device_rename+0x17a/0x1db
> > > > > >  [<ffffffff803c903d>] dev_change_name+0x114/0x20c
> > > > > >  [<ffffffff803c9339>] dev_ifsioc+0x204/0x2d0
> > > > > >  [<ffffffff803c9925>] dev_ioctl+0x520/0x633
> > > > > >  [<ffffffff803bf445>] sk_alloc+0x37/0x10c
> > > > > >  [<ffffffff8024b977>] up_read+0x9/0xb
> > > > > >  [<ffffffff803bc65e>] sock_ioctl+0x1fe/0x20c
> > > > > >  [<ffffffff8029b34a>] do_ioctl+0x2a/0x77
> > > > > >  [<ffffffff8029b5e8>] vfs_ioctl+0x251/0x26e
> > > > > >  [<ffffffff8029b664>] sys_ioctl+0x5f/0x83
> > > > > >  [<ffffffff8020bd4e>] system_call+0x7e/0x83
> > > > > > 
> > > > > > net ethxx1: device_rename: sysfs_create_symlink failed (-17)
> > > > > > sysfs: duplicate filename 'eth1' can not be created
> > > > > > 
> > > > > > Everything seems to work, but this just looks fishy.
> > > > > 
> > > > > This is a userspace program renaming your network device to a name that
> > > > > is already in use.  What distro and release is this?
> > > > 
> > > > openSUSE 10.2, with some updates (not the most recent, though).
> > > 
> > > Can you try 10.3?  I think we fixed this issue there.
> > 
> > Ehm nope:
> > 
> > Oct 16 19:36:27 carl kernel: sysfs: duplicate filename 'wlan0_rename'
> > can not be created
> > Oct 16 19:36:27 carl kernel: udev: renamed network interface wmaster0 to
> > eth1
> > Oct 16 19:36:27 carl kernel: WARNING: at fs/sysfs/dir.c:425
> > sysfs_add_one()
> > Oct 16 19:36:27 carl kernel:  [<c01b2dbf>] sysfs_add_one+0x9f/0xe0
> > Oct 16 19:36:27 carl kernel:  [<c01b3b76>] sysfs_create_link+0x86/0x110
> > Oct 16 19:36:27 carl kernel:  [<c02398ca>] device_rename+0x17a/0x1e0
> > Oct 16 19:36:27 carl kernel:  [<c015b56f>] filemap_fault+0x1ff/0x400
> > Oct 16 19:36:27 carl kernel:  [<c02b8fc0>] dev_change_name+0xb0/0x210
> > Oct 16 19:36:27 carl kernel:  [<c02b9779>] dev_ioctl+0x3c9/0x530
> > Oct 16 19:36:27 carl kernel:  [<c01a1938>]
> > inotify_d_instantiate+0x18/0x80
> > Oct 16 19:36:27 carl kernel:  [<c0120044>] do_page_fault+0x4a4/0x6f0
> > Oct 16 19:36:27 carl kernel:  [<c02ac080>] sock_ioctl+0x0/0x220
> > Oct 16 19:36:27 carl kernel:  [<c01851ab>] do_ioctl+0x2b/0x90
> > Oct 16 19:36:27 carl kernel:  [<c02ad50b>] sys_socket+0x2b/0x50
> > Oct 16 19:36:27 carl kernel:  [<c018542e>] vfs_ioctl+0x21e/0x2a0
> > Oct 16 19:36:27 carl kernel:  [<c01854ed>] sys_ioctl+0x3d/0x70
> > Oct 16 19:36:27 carl kernel:  [<c01042d6>] sysenter_past_esp+0x6b/0xa1
> > Oct 16 19:36:27 carl kernel:  =======================
> > Oct 16 19:36:27 carl kernel: net wlan0_rename: device_rename:
> > sysfs_create_symlink failed (-17)
> 
> Plus it doesn't happen on 2.6.23 on my system, so I count it as a regression.

It's a new warning I've added to the kernel to catch stupid userspace
and kernel code that is quietly failing when they are doing things
incorrectly with kobjects and sysfs.

So it's not really a "regression" in that we never notified anyone of
this kind of thing before, think of it as a new feature :)

thanks,

greg k-h