On Wed, Mar 18, 2009 at 5:16 PM, Julian Elischer <jul...@elischer.org> wrote: > Ash Gokhale wrote: >> >> I'm developing a kernel module that will be doing inspection and needed >> access to raw network frames, >> so I turned to netgraph as the solution.However it seems that netgraph >> will not permit a module >> to unload once it's participated in a mkpeer/connect operation. Rebooting >> to remove a module is >> angrymaking (not like mtx/sleep crashes). >> >> This going into the kernel because my bpf based userland stuff is >> probably not going to hold up to the packet rate. >> >> Should I file a PR? Or is there magic in the documentation I havn't found? >> >> >> I've observed the trouble in 7.0 release, and tonight's 7_RELENG, with >> GENERIC + WITNESS/INVARIANTS >> >> The module code ( cobbled together from netgraph/ng_sample.c / ng_echo.c) >> http://pastebin.com/m31b6ece6 >> >> The module loads and unloads fine until connected to a netgraph hook: > > hmm they are supposed to, and they did in the past.. > let me check... > > r...@trafmon1:kldload ng_ether > r...@trafmon1:ifconfig > bge0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500 > options=9b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM> > ether 00:11:43:30:fb:8a > inet 10.7.2.3 netmask 0xffffff00 broadcast 10.7.2.255 > media: Ethernet autoselect (100baseTX <full-duplex>) > status: active > bge1: flags=8802<BROADCAST,SIMPLEX,MULTICAST> metric 0 mtu 1500 > options=9b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM> > ether 00:11:43:30:fb:8b > media: Ethernet autoselect (none) > status: no carrier > fxp0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500 > options=b<RXCSUM,TXCSUM,VLAN_MTU> > ether 00:0e:0c:62:aa:14 > inet 10.7.0.101 netmask 0xffffff00 broadcast 10.7.0.255 > media: Ethernet autoselect (100baseTX <full-duplex>) > status: active > lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> metric 0 mtu 16384 > inet 127.0.0.1 netmask 0xff000000 > r...@trafmon1:ngctl > + list > There are 4 total nodes: > Name: bge0 Type: ether ID: 00000002 Num hooks: 0 > Name: bge1 Type: ether ID: 00000003 Num hooks: 0 > Name: ngctl4252 Type: socket ID: 00000005 Num hooks: 0 > Name: fxp0 Type: ether ID: 00000004 Num hooks: 0 > + mkpeer bge0: hole lower hook > + list > There are 5 total nodes: > Name: <unnamed> Type: hole ID: 00000006 Num hooks: 1 > Name: bge0 Type: ether ID: 00000002 Num hooks: 1 > Name: bge1 Type: ether ID: 00000003 Num hooks: 0 > Name: ngctl4252 Type: socket ID: 00000005 Num hooks: 0 > Name: fxp0 Type: ether ID: 00000004 Num hooks: 0 > + shutdown [6]: > + list > There are 4 total nodes: > Name: bge0 Type: ether ID: 00000002 Num hooks: 0 > Name: bge1 Type: ether ID: 00000003 Num hooks: 0 > Name: ngctl4252 Type: socket ID: 00000005 Num hooks: 0 > Name: fxp0 Type: ether ID: 00000004 Num hooks: 0 > + quit > r...@trafmon1:kldstat -v > Id Refs Address Size Name > 1 36 0xc0400000 6a9c28 kernel (/boot/kernel/kernel) > > [...] > > 7 1 0xccb16000 4000 ng_ether.ko (/boot/kernel/ng_ether.ko) > Contains modules: > Id Name > 246 ng_ether > 8 1 0xccb1b000 2000 ng_hole.ko (/boot/kernel/ng_hole.ko) > Contains modules: > Id Name > 247 ng_hole > r...@trafmon1:klunload ng_hole > klunload: Command not found. > r...@trafmon1:kldunload ng_hole > r...@trafmon1:kldunload ng_ether > kldunload: can't unload file: Device busy > r...@trafmon1:kldstat -v > Id Refs Address Size Name > 1 36 0xc0400000 6a9c28 kernel (/boot/kernel/kernel) > > [...] > > 7 1 0xccb16000 4000 ng_ether.ko (/boot/kernel/ng_ether.ko) > Contains modules: > Id Name > 246 ng_ether > r...@trafmon1: > > > this is expected. ng-ether is not unloadable as the connections are too > complicated to unwind easily.. one day.... > > r...@trafmon1: > >>> Stop in /root/tmp/food.ko. >>> Exit 1 >>> #Mar 18 03:14:31 kernel: quiesced >>> :ro:~/tmp/food.ko:3:14:31:32 >>> Mar 18 03:14:31 kernel: foodmod unloaded >> >> >> Seems that I can't unload some of the other netgraph types either ( it's >> not just me): >> >>> #kldunload ng_ether >>> :ro:~/tmp/food.ko:3:24:07:41 >>> kldunload: can't unload file: Device busy >>> Exit 1 > > try unloading a node that IS unloadable.. > > see the following comment in ng_ehter.c: > /* > * Note that the base code won't try to unload us until > * all nodes have been removed, and that can't happen > * until all Ethernet interfaces are removed. In any > * case, we know there are no nodes left if the action > * is MOD_UNLOAD, so there's no need to detach any nodes. > */ > > so we can't run this unless you have removeable ethernet interfaces, and > have removed them. > > > Just saw the message. Actually ng_ether can be unloaded but this is left at your own risk and there is a comment in code about this. for each $if in `ifconfig -l` ngctl shutdown $if: kldunload ng_ether
This brings the question that should ng_ether be taught about ifnet events(arrival/departure)?! -- Ermal _______________________________________________ freebsd-net@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"