Re: [Crash-utility] mount cmd crashes crash

Sorry, forgot to reply all: --------------------------- On Wed, 2010-08-18 at 20:57 +0000, Dave Anderson wrote: > ----- "Bob Montgomery" <bob.montgomery(a)hp.com&gt; wrote: > > > I'm working on a dump of a system that did not have a PID 1. I don't > > think it's relevant to the crash itself, but it does cause crash get > > a seg fault. > > > > I don't know if it was important to have the context of pid 1 for > > reporting mounts, or just any context, but this hack makes the problem > > go away, although not a very efficient way to find the lowest existing > > PID above 0. > > Yeah, it's not important to use the context of pid 1, but it just needs > some context, and I had presumed that init would always exist. I thought > that the panic("Attempted to kill the idle task!") in do_exit() would > prevent pid 1 from ever going away -- but apparently your kernel figured > out how to do it elsewhere... ;-) That test is for PID 0, not PID 1 (at least on the kernel I'm debugging.) However, there is this also: if (unlikely(tsk == child_reaper)) panic("Attempted to kill init!");

And child_reaper in the dump points to a task struct for init that isn't in the ps listing. Hmmm. Maybe that part *is* interesting in this dump... > > Your patch would pick a kernel thread pid, and apparently everything still > works OK? That being the case, it's fine with me. With the patch, these commands all produce the same output: crash-5.0.6-fix> mount >mount.out crash-5.0.6-fix> mount -n 2 >mount2.out crash-5.0.6-fix> mount -n 1459 >mount1459.out I discovered the -n option as my first workaround.