> sysfs is "one value per file" What about existing interfaces that even export binary blobs through sysfs (e.g. /sys/firmware, /sys/boot_params)? What qualifies as a "value" in that case? > please put something like this in > tracefs, as there is no such rules there. Or debugfs, but please, not > sysfs. Does tracefs have anything similar to sysfs_notify() or any other way to implement a poll() handler? Our main goal is to let users wait on poll(), so that they don't have to check the file for new contents every now and then. Is it possible with tracefs or debugfs? Also, for our goal debugfs isn't a particularly good fit, as Android kernels do not enable debugfs. Not sure about tracefs, they seem to have it, need to check. Do you think it is viable to keep /sys/kernel/error_report/report_count in sysfs and use it for notifications, but move last_report somewhere else? (I'd probably prefer procfs, but it could be tracefs as well, if you find that better). This way it will still be possible to easily notify userspace about new reports, but the report itself won't have any atomicity guarantees. Users will have to check the report count to ensure it didn't change under their feet. > Also, any reason you didn't cc: the sysfs maintainers? Only my lack of common sense :) I'll add them should the following patches rely on sysfs, thank you! Alex -- Alexander Potapenko Software Engineer Google Germany GmbH Erika-Mann-Straße, 33 80636 München Geschäftsführer: Paul Manicle, Halimah DeLaine Prado Registergericht und -nummer: Hamburg, HRB 86891 Sitz der Gesellschaft: Hamburg