On Mon, Jan 09, 2017 at 02:31:39AM +0000, Anindya Mukherjee wrote: > Hi Ben, > > Thanks for your reply, and yes, I did notice #238. I should say at this point > that I'm a newbie when it comes to kernel code and am trying to learn about > it (hence current).
Understood. It's good that you are ready to try! > The entry you refer to does look a bit like the one I've got, but I'm not > totally sure if the same code path is being followed to arrive at this LOR. > An inode is being created in my case, vs a directory creation (entry + inode > probably) in #238, and then a sync is being attempted, which causes locks to > activate in the softdep code. I've read a bit about this from McCusick's book > but the details are still fuzzy. > > Perhaps you are trying to tell me that it's benign? I know that WITNESS has > false positives, an example being #236 where due to shared vs exclusive vnode > locks required on the two ways to lock bufwait and dirhash a deadlock never > happens. Well, it's hard to say for certain, but there are a few ufs/bufwait/ufs LORs that are very commonly reported as WITNESS output but have never (IIRC) been identified as causing a deadlock. So, it seems pretty likely that this one is similarly benign -- I, for one, do not plan to put in time trying to analyze it until there is a hang or deadlock associated with it. -Ben _______________________________________________ freebsd-current@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
