STR: stop the GMP plugin-container process, either by sending it SIGSTOP or attaching with gdb. Result: the parent process, if it's a debug build, crashes thusly: [29670] ###!!! ABORT: file /home/jld/src/mozilla-central/ipc/chromium/src/base/shared_memory_posix.cc, line 220 Hit MOZ_CRASH() at /home/jld/src/mozilla-central/memory/mozalloc/mozalloc_abort.cpp:30 This is because it ran out of file descriptors, as seen here in /proc/<pid>/fd: lrwx------ 1 jld jld 64 Jun 11 12:02 91 -> /run/shm/org.chromium.O1wYu3 (deleted) lrwx------ 1 jld jld 64 Jun 11 12:02 92 -> /run/shm/org.chromium.n9a8Be (deleted) lrwx------ 1 jld jld 64 Jun 11 12:02 93 -> /run/shm/org.chromium.tVI7P3 (deleted) [...] lrwx------ 1 jld jld 64 Jun 11 12:02 1021 -> /run/shm/org.chromium.qGAOch (deleted) lrwx------ 1 jld jld 64 Jun 11 12:02 1022 -> /run/shm/org.chromium.IH9E7v (deleted) lrwx------ 1 jld jld 64 Jun 11 12:02 1023 -> /run/shm/org.chromium.IH9E7v (deleted)

It sounds as if bug 1020090 would take care of this.