Beginning with F21, syslinux lost the ability to install to a USB stick: > sudo syslinux /dev/sdf plain floppy: device "/proc/13122/fd/3" busy (Resource temporarily unavailable): Cannot initialize 'S:' Bad target s:/ldlinux.c32 The old 4.05 version in F20 seems to work OK. I did a bit of searching and found this discussion: https://groups.google.com/a/chromium.org/forum/#!msg/chromium-os-dev/bRPUCFHoBTQ/ZjB8kjjx1vUJ Which includes the following: " All confirmed: inserting a 10ms sleep in mtools just before the flock() syscall makes the problem go away, whereas a 1ms is not long enough to avoid it. Removing LOCK_NB also makes it work. syslinux forks and closes mattrib/mtools in rapid fire - apparently too fast for the loopback flock to be actually released. " Of course, this is talking about running syslinux on a loop device, but the problem appears to be the same. It could be an mtools problem instead, but mtools hasn't really changed in 2.5 years. I guess the older version of syslinux didn't call mtools at all, so this didn't show up.
The problem on the loop device is a locking race between recent versions of udev and mtools. See discussion linked above for all details.
Fedora 22 changed to end-of-life (EOL) status on 2016-07-19. Fedora 22 is no longer maintained, which means that it will not receive any further security or bug fix updates. As a result we are closing this bug. If you can reproduce this bug against a currently maintained version of Fedora please feel free to reopen this bug against that version. If you are unable to reopen this bug, please file a new report against the current release. If you experience problems, please add a comment to this bug. Thank you for reporting this bug and we are sorry it could not be fixed.