Corey Minyard wrote: > > I'm trying to get KDB working properly on an SMP machine, and it seems > to have some problems. There's KDB_VECTOR, which doesn't seem to be > tied to anything but seems to be used to stop the other CPUs, > KDBENTRY_VECTOR, which is for initial entry. In general, the SMP code > seems half-done in the patches on the FTP site. > > kdb enters ok and I can debug on the CPU that entered KDB, but I am > unable to switch to the other CPU and it seems to still be running. > > I read some discussion on the mailing list about this, but there doesn't > seem to be any resolution. Is there any? > > Thanks, > > -Corey
Hi Corey, It sounds like you have a bad merge. Kdb generally works pretty well straight out of the bo if you use it with the matching kernel.org kernel. The problem you describe sounds like what I saw mixing kdb with kgdb stubs. At least on the x86 the KDB_VECTOR is mostly smoke and mirrors. The lowest level of send_IPI functions just sends a broadcast NMI, and the do_nmi() handler has to guess what caused the interrupt. There are probably still smp timing issues, but they are more subtle. Jim Houston - Concurrent Computer Corp.
