graphic: 0.903 device: 0.795 network: 0.688 performance: 0.686 semantic: 0.600 PID: 0.584 socket: 0.569 boot: 0.534 other: 0.523 vnc: 0.504 files: 0.489 permissions: 0.487 debug: 0.431 KVM: 0.136 qemu-user fails to run rpcgen (i386, x86_64) Confirmed on qemu current development tree (git commit aa29141). While trying to run eglibc's rpcgen from native system by qemu-user, I get an error: qemu-x86_64 /usr/bin/rpcgen -c /dev/null fork: Invalid argument I am running a Debian Wheezy system and rpcgen comes from libc-dev-bin. Just in case I am attaching my rpcgen binaries from i386 and x86_64 systems. Very similar problem was mentioned on the QEMU forum on February 2007, so I guess it might be a known issue. Nevertheless, I was unable to find any information about bug reports, fixes nor workarounds for it so I'm reporting it here. This should be fixed in QEMU 1.6.