Messages in this thread | ![/](/images/icornerl.gif) | | Date | Mon, 2 Mar 2015 14:18:05 +0000 | From | Alan Cox <> | Subject | Re: [PATCH 0/8] introduce dynamic device creation/removal |
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> > This is a long term plan, of course, but I'd like to see sysfs functions go away > > in a year or so. What do you think? > > hoo boy. Creating a /dev node and doing ioctls on it is really old > school. So old school that I've forgotten why we don't do it any more. > > Hopefully Alan can recall the thinking?
Gee.. pass me the walking stick and the pipe !
The problem we used to have with it was re-use of /dev nodes and permissions. For example if I create a ZRAM instance and then we crash and my /dev is persistent then next boot I can potentially be opening that left over node (or it may even be forgotten), which has old and stale permissions on it.
With devtmpfs it's a bit easier and saner.
The old abuser of this was the old PCMCIA layer which has more exciting versions of the problem as it used /tmp for some nodes.
Switching to sysfs probably fits better but the problem is the generic one of revoking access rights to an object.
Alan
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