Ferenc Wagner wrote: > Hi, > > as of git 305bc646, the following happens: > > # strace -f lxc-unshare -s NETWORK > [...] > clone(Process 3085 attached (waiting for parent) > Process 3085 resumed (parent 3084 ready) > child_stack=0xbfe836d4, flags=0x40000000|SIGCHLD) = 3085 > [pid 3085] getpid() = 3085 > [pid 3085] --- SIGSEGV (Segmentation fault) @ 0 (0) --- > Process 3085 detached > waitpid(3085, [{WIFSIGNALED(s) && WTERMSIG(s) == SIGSEGV}], 0) = 3085 > --- SIGCHLD (Child exited) @ 0 (0) --- > exit_group(11) = ? > > On the other hand, 'lxc-unshare -s NETWORK -- ifconfig -a' works all > right. If I read the history correctly, lxc-unshare now always forks, > but the argument checking didn't follow this, so execvp fails when > args=NULL. The usage notes should also be changed to reflect this, and > the -f switch is past as well. "Ored list of flags" isn't particularly > clear, btw, and also a little cumbersome to use on the command line. > Why not do away with all the complexity of expression and parsing and > enable repeated -s options? Okay, it's a testing tool, but still... :) > Agree, that makes sense.
> I can see that lxc-unshare isn't for me: I wanted to use it to avoid > adding the extra lxc-start process between two daemons communicating via > signals, but it's impossible to unshare PID namespaces, so I'm doomed. > There is a pending patchset to unshare the pid namespace, maybe for 2.6.35 or 2.6.36 ... > But now I see that signal forwarding was just added to lxc-init, would > you consider something like that in lxc-start as well? > It's the lxc-init process who forward the signals. The lxc-kill sends a signal to the pid 1 of the container. When lxc-init is the first process, it receives the signal and forward it to the pid 2. In the case of lxc-start, let's say 'lxc-start -n foo sleep 3600'. The 'sleep' process is the first process of the container, hence if you 'lxc-kill -n foo <signum>' command, that will send the signal to 'sleep'. ------------------------------------------------------------------------------ _______________________________________________ Lxc-users mailing list Lxc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/lxc-users