On Sat, Oct 13, 2012 at 9:21 AM, Larry McVoy <lm@xxxxxxxxxxxx> wrote: > > Ahh, I've been away from the kernel too long. I miss that delicate > management touch. "Delicate Management Touch" is my middle name. > pics of the stack trace at http://www.mcvoy.com/lm/nfs-lock-crash Ok, that's just the normal kind of random left-over oopses due to subsequent problems of a BUG_ON(). Looks like the watchdog timer ends up being unhappy, almost certainly simply because some core filesystem spinlock not being released. It used to be (a long long time ago) that we'd recover fairly gracefully from BUG_ON()'s - back when the main shared lock we had was the kernel lock, and we had a single per-process kernel lock counter. So when we killed the process, we could clean that single lock up. These days, if some process dies in random kernel code due to a BUG_ON() or a wild pointer or similar, and we kill it, we are seldom able to do so cleanly. So the best we can hope for is that it happened in some context where it held no (important) locks. Which is rare. So BUG_ON()'s are often fatal, and there are these kinds of downstream problems where they get flushed off the screen by subsequent issues... Ho humm. Google doesn't seem to be finding any similar bug-reports, so unless Bruce or Trond go "Ahh, I know what it's about", I do think we would want to get as much more info as possible. Doing a kernel compile really isn't that bad. The only nasty piece is getting the kernel configuration right, but you can just use the distro config. It's much too big and contains everything, but it will work, and gets you as similar a kernel as possible. Of course, Ubuntu has made installing your own kernel stupidly complicated (you have to build a package and install it using the package manager), but while it's an annoying extra step or two (compared to just doing a "make modules_install install"), it's not rocket surgery. There's a few help pages for it: https://help.ubuntu.com/community/Kernel/Compile being the first one. Linus -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
