Hello,
I would prefer addressing this problem on the public mailing list. I do not mind anyone contacting me directly. The version of RTAI the LinuxCNC developers are using is a depreciated fork of RTAI 3, which is also depreciated upstream. NULL pointer deference bugs is usually caused by an improper kernel config, and the last time I looked at the RTAI kernel config used by LinuxCNC, there were options set that should not enabled. https://cateee.net/lkddb/web-lkddb/LSM_MMAP_MIN_ADDR.html If it is not already set to 65536, set to 65536. I never have NULL pointer deference bugs if that value is set properly. Outside of that, I recommend building updated RTAI packages as nobody (not myself, Shabby, or Paolo) can really know what's going on as none of us have used that code in years. For a working tree: https://github.com/NTULINUX/RTAI Master branch and the 4.9.9 tarball are the same. I will not be updating branch `master` until I build a Ryzen system and get RTAI 5 working on it. RTAI 5.2 is in the works but all development so far is behind closed doors so I can't see what's going on. RTAI 5.2 will be my new development platform and I will fix everything bound to broken in it, as always. I'd recommend updating to a more recent version of Debian as well when RTAI 5.2 stabilizes as I cannot even use Debian wheezy for anything other than LinuxCNC as the libraries and development tools are too old. Compiling and building anything is nothing but a pain due to dependencies being out of date. For LinuxCNC it's fine but for a general purpose desktop _and_ LinuxCNC, my only viable option is building the whole system myself with Gentoo. This gets me the versions of Clang, LLVM and python libraries I need. RTAI 5.2 will have kernel 4.14 support, which has spectre+meltdown fixes, modern GPU support (stable amdgpu driver) and many other fixes. 4.14 is also LTS, and currently supported. Kernel 3.4 is EOL and has been for awhile. Debian wheezy is a security risk at this point in time. While this may be off-topic to andypugh's initial question, it's important to note. If following RTAI development and building packages for it becomes too tasking and impractical, leave RTAI support in LinuxCNC for those who need it, but don't bother shipping it with anymore live CDs. Update Debian, base the shipped version of LinuxCNC against this: https://packages.debian.org/stretch/linux-image-rt-686-pae And be done with it. It's the easiest approach and requires the least amount of time in the long run. If you still want to support RTAI in package format, have 2 different versions of LinuxCNC that conflict with one another so dpkg will not allow both to be installed at once. LinuxCNC-preempt-rt (the default) and LinuxCNC-RTAI which uses RTAI as the back-end. Have LinuxCNC-RTAI depend on an RTAI kernel package (linux-image-rtai-686-pae for example) and RTAI itself (rtai-modules-686) and have it uninstall LinuxCNC-preempt-rt. I have no say in any of this, I'm not telling anyone to do anything, this is just a suggestion, do with it as you wish. Alec ________________________________ From: andy pugh <[email protected]> To: Alec <[email protected]> Sent: Wednesday, November 28, 2018 4:36 AM Subject: handle_lxrt_request Sorry to bother you directly, https://forum.linuxcnc.org/26-turning/27330-eccentric-turning?start=30#121496 Looks like a crash inside RTAI? Do you agree? -- atp "A motorcycle is a bicycle with a pandemonium attachment and is designed for the especial use of mechanical geniuses, daredevils and lunatics." — George Fitch, Atlanta Constitution Newspaper, 1916 _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
