On Fri, Nov 29, 2019 at 10:33:39AM +0100, Paolo Bonzini wrote: > On 29/11/19 10:27, Daniel P. Berrangé wrote: > >> Yes, with a fallback path currently using a temporary file under /tmp > >> (we may want to use shm_open() instead, or a different location such > >> as XDG_RUNTIME_DIR? - and use O_TMPFILE) > > We can't assume either /tmp or XDG_RUNTIME_DIR is on tmpfs as that is no > > where near standard across all OS distros, and even if on tmpfs these > > dirs can be size limited to a significant subset of available RAM. IOW > > we can't safely use them unless explicitly told to. > > Agreed, mkstemp+shm_open seems better. Perhaps this could be done in > hostmem-memfd.c though, basically as a fallback option? In principle > one could even use getmntent to search for a hugetlbfs mount.
With mkstemp you still need to pick a location, and I don't think it is clear there is a reliable choice that will always work. Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|