Hi Vikash... On Tue, Mar 2, 2010 at 1:14 PM, Vikash Kumar <vikashskumar@xxxxxxxxx> wrote: > Hi all, > > I am developing a raid system and I am getting following BUG when I > issue lots of parallel IO. > I am not able to figure out how to go about debugging this dump. It's > evident here that RAID_LAZY_WRITE thread is trying to > schedule while it has locked the CPU but I am not able to trace it > exactly how and why it's happening. > As I don't acquire any lock to issue IO to block layer. > > I enabled spin lock debugging and lock dependency checking so that I > could get detailed debug info. > Here is the whole dump which I got, please provide me tips, ideas on > how to analyze and debug using > this dump. IMHO there are many possibilities here. The best thing to do here is to check the related functions mentioned in the stack frames. Are they really don't schedule while holding any locks on any situations? Are they somekind of callbacks that must satisfy certain kind of rules? Maybe it's like signal handler in user space which must avoid reentrancy etc. Sorry, this tip might sounds blurry for now, but this is the best idea I can offer right now. PS: When you mention "developing RAID system", do you mean "developing RAID handling code"? Or simply implementing RAID 0/1/5/01/10/1+5/5+1/etc disk array? -- regards, Mulyadi Santosa Freelance Linux trainer and consultant blog: the-hydra.blogspot.com training: mulyaditraining.blogspot.com -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
