[PATCH v3 1/4] firmware: introduce sysfs driver for QEMU's fw_cfg device

[Andy Lutomirski]

On Sat, Oct 3, 2015 at 4:28 PM, Gabriel L. Somlo <somlo at cmu.edu> wrote:
> From: Gabriel Somlo <somlo at cmu.edu>
>
> Make fw_cfg entries of type "file" available via sysfs. Entries
> are listed under /sys/firmware/qemu_fw_cfg/by_key, in folders
> named after each entry's selector key. Filename, selector value,
> and size read-only attributes are included for each entry. Also,
> a "raw" attribute allows retrieval of the full binary content of
> each entry.
>
> This patch also provides a documentation file outlining the
> guest-side "hardware" interface exposed by the QEMU fw_cfg device.
>

What's the status of "by_name"?  There's a single (presumably
incorrect) mention of it in a comment in this patch.

I would prefer if the kernel populated by_name itself rather than
deferring that to udev, since I'd like to use this facility in virtme,
and I'd like to use fw_cfg very early on boot before I even start
udev.

--Andy