Robert Scott wrote: > Hello, > > I know that this bug has been discussed before at length on this > mailing list, but previous post seemed to indicate that it was fixed > before kernel 2.6.12. I am still seeing this occasionally in kernel > 2.6.12.3. The system is running knoppix, and IPV6 is not compiled into > the kernel(other posts mentioned numerous problems with the IPV6 > code). But every so often, when bringing down the bridge (it doesn't > happen every time), the process hangs, and the following message > appears in dmesg repeatedly: > > 'unregister_netdevice: waiting for br0 to become free. Usage count = 1' I have found an appearant leak of a route object, which holds a reference to a device. I reproduced in both 2.6.11 and 2.6.13 using 802.1Q VLANs. I have a patch that will print out the place of the leaked reference against 2.6.13. http://www.candelatech.com/oss/rfcnt.patch Enable the feature in the Networking section of Kconfig. If you can reproduce with this patch in place, you will get a file and line number for the leak..please CC me. I'm going to try to debug the leak, but I could definately use some help... > None of the processes involved can be killed, and an attempt to run an > ifconfig results in a process that is also waiting forever. At this > point the box must be rebooted forcefully. > > Two questions. > 1. In a previous post, someone mentioned one solution was to commenting > out the check that is hanging in the kernel. Does this check > preventing something terrible from happening(i assumed that it does), > or is it safe to remove it. This would be bad...could lead to memory corruption. > 2. Any ideas of something to try in order to make this repeatable? I have a complex application with a complex script to drive it that reproduces the problem within an hour...I haven't found a simpler way.... Thanks, Ben -- Ben Greear <greearb@xxxxxxxxxxxxxxx> Candela Technologies Inc http://www.candelatech.com
