Correcting a few mistakes in the original report...

So, I swear when I first looked at the patches, it looked like Debian had messed with sections dealing with LABELs. Not true. Just simple replaces of slashes with backslashes. Apologies!

It was silly to specify the 4096 argument to jfs_mkfs, which looked like a default value anyway, as I was interpreting it differently than what I
thought the manpage was saying. Simple, though. My original one-liner simplifies from:

$ sudo jfs_mkfs -j /dev/mapper/luks-xmr-blockchain-log -L XmrBlockchain -s 128 /dev/mapper/luks-xmr-blockchain 4096

becomes:

$ sudo jfs_mkfs -j /dev/mapper/luks-xmr-blockchain-log -L XmrBlockchain -s 128 /dev/mapper/luks-xmr-blockchain

Otherwise, without stripping that argument, the main JFS filesystem yields
me a filesystem of only 16 GB, rather than the full space of the block
device! Now that it is gone, the blockchain I desired is being quickly acquired, on a good TB SSD. Not as quickly as I'd like, but quickly enough
;)

Last, I swear I had seen the function (a different one) where jfs_tune
prints the LABEL out, but may have hallucinated. I tracked this all the way
to a function logsuper (or superlog), which appears to be "doing the right thing". Perhaps, there's a different happy-path when the filesystem(s) are mounted versus *not* mounted, or LOG filesystem attached versus
not-attached... I say this, because I did _successfully_ put a 16 character LABEL on the LOG device once, shortly after the bugreport, while I was still using that 4096 argument to jfs_mkfs, and no terminal garbage appeared. In logsuper, the code following the printf for the LABEL is more printf calls
to show active filesystems to which this LOG device is connected, rather
than the LOG filesystem's UUID (which I gleaned from that super.h header
file, and made an incorrect assumption).

After realizing the 4096 argument messed up the size of the filesystem, I omitted it, and again tried to put the same LABEL back onto the LOG block device, for the last time. The garbage terminal output returned :( So, maybe jfs_tune does have two ways to print out the LOG filesystem information.
After another very quick, superficial glance, I noted some code that does
check to either see if something is mounted or not, before branching, nearby the code that ends up calling the logsuper function.

Thank you for maintaining this package. I am happy with jfsutils in Debian! Forgive me that I do not have the time to really properly investigate
further right now, and I report this days later, which might yield more inaccuracies (such as the function name, perhaps).

Jerad Simpson

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