From mboxrd@z Thu Jan 1 00:00:00 1970 From: somlo@cmu.edu (Gabriel L. Somlo) Date: Tue, 6 Oct 2015 14:17:03 -0400 Subject: [PATCH v3 1/4] firmware: introduce sysfs driver for QEMU's fw_cfg device In-Reply-To: References: <1443914889-9619-1-git-send-email-somlo@cmu.edu> <1443914889-9619-2-git-send-email-somlo@cmu.edu> Message-ID: <20151006181703.GG1962@HEDWIG.INI.CMU.EDU> To: kernelnewbies@lists.kernelnewbies.org List-Id: kernelnewbies.lists.kernelnewbies.org On Tue, Oct 06, 2015 at 10:54:42AM -0700, Andy Lutomirski wrote: > On Sat, Oct 3, 2015 at 4:28 PM, Gabriel L. Somlo wrote: > > From: Gabriel Somlo > > > > 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. "by_name" is added with patch 4/4 of the series, which I kept separate due to the "To udev or not to udev" conversation from earlier. So far I haven't yet figured out just HOW I'd set it up in udev, but it works already if done in the kernel :) Thanks, --Gabriel