lubkin@cs.rochester.edu (Saul Lubkin) (04/23/91)
The ISC cc links in some startup code from /lib -- I think crt[01].o -- on invocation. Apparantly, when "-Xp" is used, alternative POSIX compliant startup code is used instead -- perhaps crtp[01].o, or something else. /lib contains crt[01].o, crtn.o, crtp[01].o, mcrt[01].o, mcrtp1.o, pcrt[01].o and pcrtp1.o. Could someone enlighten me as to which of these are linked in when? This is relevant to my trying to create a useable job control support version of bash for ISC 2.2. I have made a job control bash -- but it causes a system panic when vpix is run under it. Sincerely, Saul Lubkin
kdenning@pcserver2.naitc.com (Karl Denninger) (04/24/91)
In article <1991Apr23.145657.8672@cs.rochester.edu> lubkin@cs.rochester.edu (Saul Lubkin) writes: >The ISC cc links in some startup code from /lib -- I think crt[01].o >-- on invocation. Apparantly, when "-Xp" is used, alternative POSIX >compliant startup code is used instead -- perhaps crtp[01].o, or >something else. > >/lib contains crt[01].o, crtn.o, crtp[01].o, mcrt[01].o, mcrtp1.o, >pcrt[01].o and pcrtp1.o. > >Could someone enlighten me as to which of these are linked in when? > >This is relevant to my trying to create a useable job control support >version of bash for ISC 2.2. I have made a job control bash -- but it >causes a system panic when vpix is run under it. > > Sincerely, > > Saul Lubkin The panics aren't surprising to me. Any application compiled on ISC with '-Xp' is likely to do this. Trn does it. Others do it. The problem is with a null pointer dereference in the kernel routine "namei()". There is an "unofficial" fix which was posted to the net, but I have no idea if it does the "right thing" if it detects the null dereference (it does stop the panics). I have reported it. The word is that it will be fixed in the 2.3 release, which has no firm release date at this time, or a cost for upgrade. There are no current plans for a patch from what I have been told. The bottom line: POSIX anything does not work at all on ISC 2.2. Don't even bother trying; you'll end up like me (had a machine crashing daily for a week and a half before I realized that it was posix that had caused the troubles). It is likely to be months before there is a fix available for this problem. I would (of course) like to see something sooner. I've backed out all POSIX applications on both my home system and all ISC machines here at Nielsen. Panics aren't something that are a lot of fun on a system with 1.5GB of disk space (45 minute + reboot times bite). -- Karl Denninger - AC Nielsen, Bannockburn IL (708) 317-3285 kdenning@nis.naitc.com "The most dangerous command on any computer is the carriage return." Disclaimer: The opinions here are solely mine and may or may not reflect those of the company.
gemini@geminix.in-berlin.de (Uwe Doering) (04/25/91)
lubkin@cs.rochester.edu (Saul Lubkin) writes: >/lib contains crt[01].o, crtn.o, crtp[01].o, mcrt[01].o, mcrtp1.o, >pcrt[01].o and pcrtp1.o. > >Could someone enlighten me as to which of these are linked in when? > >This is relevant to my trying to create a useable job control support >version of bash for ISC 2.2. I have made a job control bash -- but it >causes a system panic when vpix is run under it. That's how I found out about the bug in the namei() kernel function (NULL pointer dereference). I also tried to run VP/ix in kernel POSIX mode, and the system paniced. I posted a binary patch to fix this problem. With this patch installed, you will find that VP/ix no longer causes a kernel panic, but it still won't work. If I remember correctly, this is because VP/ix tries to open the serial ports with the O_EXCL flag, which, in POSIX mode, obviously isn't allowed for devices. BTW, ISC told me that they already knew about the bug in namei(), and that it is fixed in their current (internal) release. However, they didn't tell me whether they intend to release a fix disk for this problem, or whether we have to wait until the next major release. Uwe -- Uwe Doering | INET : gemini@geminix.in-berlin.de Berlin |---------------------------------------------------------------- Germany | UUCP : ...!unido!fub!geminix.in-berlin.de!gemini