Date: Mon, 23 Mar 2009 13:20:21 -0400 From: Ash Gokhale <ash@aeria.net> To: freebsd-net@freebsd.org Subject: netgraph modules won't unload after use Message-ID: <6CE36549-DDB7-43A2-88B4-C2D171FA13F1@aeria.net>
next in thread | raw e-mail | index | archive | help
> Thanks for looking at it Julian, I still can't figure out which resource it needs to release before exiting. I've replaced the raw ether_input routine on the interface to continue my module until I can figure out what's wrong with my netgraph glue. Again this minimal module demonstrates the trouble, I'd appreciate it if some sage could say "there's your trouble" http://pastebin.com/m31b6ece6 > netgraph modules won't unload after use > Julian Elischer julian at elischer.org > Wed Mar 18 09:16:15 PDT 2009 > > * Previous message: netgraph modules won't unload after use > * Next message: kern/126469: [fxp] [panic] fxp(4) related kernel > panic > * Messages sorted by: [ date ] [ thread ] [ subject ] [ author ] > > 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... > > root at trafmon1:kldload ng_ether > root at 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 > root at 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 > root at 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 > root at trafmon1:klunload ng_hole > klunload: Command not found. > root at trafmon1:kldunload ng_hole > root at trafmon1:kldunload ng_ether > kldunload: can't unload file: Device busy > root at 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 > root at trafmon1: > > > this is expected. ng-ether is not unloadable as the connections are > too complicated to unwind easily.. one day.... > > root at 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. > > > > > > > > > _______________________________________________ > > freebsd-net at freebsd.org mailing list > > http://lists.freebsd.org/mailman/listinfo/freebsd-net > > To unsubscribe, send any mail to "freebsd-net-unsubscribe at > freebsd.org" > > * Previous message: netgraph modules won't unload after use > * Next message: kern/126469: [fxp] [panic] fxp(4) related kernel > panic > * Messages sorted by: [ date ] [ thread ] [ subject ] [ author ] > > More information about the freebsd-net mailing list >
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?6CE36549-DDB7-43A2-88B4-C2D171FA13F1>