On Thu, Dec 31, 2015 at 4:27 PM, Stephen R. van den Berg <s...@cuci.nl> wrote: > Stephen R. van den Berg wrote: >>I'm running 4.4.0-rc7. >>This exact problem was present on 4.0.5 and 4.3.3 too though. > >>I do a "btrfs send /var/lib/lxc/template64/rootfs", that generates >>the following error consistently at the same file, over and over again: > >>Dec 29 14:49:04 argo kernel: kernel BUG at fs/btrfs/send.c:1482! > > Ok, found part of the solution. > The kernel bug was being triggered by symbolic links in that > subvolume that have an empty target. It is unknown how > these ever ended up on that partition.
Well they can happen due a crash or snapshotting at very specific points in time when an error happens while creating a symlink at least. I've sent a change for send that makes it not BUG_ON() but instead fail with an EIO error and print a message do dmesg/syslog telling that an empty symlink exists: https://patchwork.kernel.org/patch/7936741/ As for fixing the (very) rare cases where we end up creating empty symlinks, it's not trivial to fix. Thanks. > > The partitions have been created using regular btrfs. > The only strange thing that might have happened, is that I ran duperemove > over those partitions afterward. > -- > Stephen. > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Filipe David Manana, "Reasonable men adapt themselves to the world. Unreasonable men adapt the world to themselves. That's why all progress depends on unreasonable men." -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
