Thanks Rick. Just when I thought I was almost done. :-) I’m used to CMS, zOS and TPF where a properly authorized “problem program” can switch in and out of supervisor state.
Do you have any reading material you can point me to? I gather this will be something I have to modprobe-load to make available? Cheers Don On Sat, Nov 10, 2018 at 08:07 Rick Troth <r...@casita.net> wrote: > Supervisor state is the domain of the kernel in most contemporary systems, > including Linux. What you need to do for DIAG A0 is write a kernel module. > > Your next hurdle is interfacing kernel modules. There was one guy who > implemented a generic DIAG interface early in the life of Linux on Z. But > it was mostly used just for DIAG 08 and so fell out of use when the IBM > DIAG 08 interface (with no support for other DIAG codes) came on the scene. > > -- R; <>< > > > > > On Sat, Nov 10, 2018, 10:32 Donald Russell <russell....@gmail.com wrote: > > > Thanks Neale! > > > > In my case I’m using diag a0. Though I may want to do this for other diag > > instructions too. > > > > Getting in/out of supervisor state is my next hurdle. :-) > > > > I was going to use stidp to make sure I was actually on VM but that got > > “Illegal Instruction” when it ran. > > Maybe there’s a function I can call, or I can read /proc/cpuinfo to > verify > > A-it’s IBM/S390 and B-VM is running. I don’t like the idea of reading a > > whole “file” to provide what a single instruction can give me. > > > > I still have to figure out how to get in and out of supervisor state for > > the diag though. > > > > Thanks for tip on generating the machine code. That’s great! :-) > > > > Cheers, > > Don > > > > > > > > > > On Sat, Nov 10, 2018 at 03:31 Neale Ferguson <ne...@sinenomine.net> > wrote: > > > > > .byte 0x83, 0x12, 0x00, 0x08 > > > > > > == diag 1,2,8 (CP command) > > > > > > You can either load r1/r2 in the _asm_ section or tell gcc to bind the > > > variables to the registers. > > > > > > Remember, though, that diag is a privileged instruction and won't work > in > > > a userland program. > > > > > > In what particular diag are you interested? > > > > > > > > > -------- Original message -------- > > > From: Donald Russell <russell....@gmail.com> > > > Date: 11/10/18 06:00 (GMT-05:00) > > > To: LINUX-390@VM.MARIST.EDU > > > Subject: [LINUX-390] Using diagnose instruction from C on RHEL 7 > > > > > > Hello, > > > > > > I want to write a program in C and use a diagnose instruction. > > > > > > I thought I could do > > > > > > __asm___( “ diag ... “ ...); > > > > > > but that fails because diag is not a real instruction mnemonic. When I > > use > > > gcc to compile and link I get an error: > > > > > > Program.c(.text+0x578): undefined reference to ‘x480a032’ > > > collect2: error: ld returned 1 exit status > > > > > > I thought I could code dc x’8312....’ and force the use of registers 1 > > and > > > 2 but it complains that dc is not valid. (The doc says instructions > > > including directives are ok. But obviously not dc directives. :-) I > > also > > > tried upper case just to be thorough) > > > > > > How can I coerce C into generating a diagnose instruction? > > > > > > Thanks, > > > Don > > > > > > ---------------------------------------------------------------------- > > > For LINUX-390 subscribe / signoff / archive access instructions, > > > send email to lists...@vm.marist.edu with the message: INFO LINUX-390 > or > > > visit > > > http://www.marist.edu/htbin/wlvindex?LINUX-390 > > > ---------------------------------------------------------------------- > > > For more information on Linux on System z, visit > > > http://wiki.linuxvm.org/ > > > > > > ---------------------------------------------------------------------- > > > For LINUX-390 subscribe / signoff / archive access instructions, > > > send email to lists...@vm.marist.edu with the message: INFO LINUX-390 > or > > > visit > > > http://www.marist.edu/htbin/wlvindex?LINUX-390 > > > ---------------------------------------------------------------------- > > > For more information on Linux on System z, visit > > > http://wiki.linuxvm.org/ > > > > > > > ---------------------------------------------------------------------- > > For LINUX-390 subscribe / signoff / archive access instructions, > > send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or > > visit > > http://www.marist.edu/htbin/wlvindex?LINUX-390 > > ---------------------------------------------------------------------- > > For more information on Linux on System z, visit > > http://wiki.linuxvm.org/ > > > > ---------------------------------------------------------------------- > For LINUX-390 subscribe / signoff / archive access instructions, > send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or > visit > http://www.marist.edu/htbin/wlvindex?LINUX-390 > ---------------------------------------------------------------------- > For more information on Linux on System z, visit > http://wiki.linuxvm.org/ > ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For more information on Linux on System z, visit http://wiki.linuxvm.org/
