dpaulso@k30b.nswc.navy.mil (Dave Paulson) (02/12/91)
The setup: CCI power6/32, VIOC tty controllers, Sytek LAN hardware. The scenario: occasionally, our Sytek SMUX will get reset and users will be disconnected from their power6/32 ports. Now _usually_, these users' processes will receive the necessary signals which cause them to clean themselves up and go away. The problem: sometimes they don't. When this happens, a new user can connect to the port from which an old user has been thrown off, and, without having to log in, can gain control of the old user's processes. My questions: I've compared our tty driver to drivers written for DH-11s and DZ-11s. In the situation I've described, both of these drivers signal (SIGHUP and SIGCONT) the process group _before_ clearing the TS_CARR_ON flag in the tty struct; but our VIOC driver clears the flag first, and then signals the process group. Is this significant? Is there a race in the VIOC driver? If not, would it help (or hurt) to raise the processor priority level while cleaning up a detached line? /dave -- Dave Paulson dpaulso@relay.nswc.navy.mil (work) Synetics/NAVSWC talos!SandBox!dave@uunet.uu.net (home,NeXTmail)