Re: [Gnu-arch-users] On incompetent uses of English

[Stephen J. Turnbull]

>>>>> "Derek" == Derek Zhou <address@hidden> writes:

    Derek> I did, indirectly.

OK.  Still, when Tom reiterates the argument I think it deserves
reconsideration.

    Derek> I said inode sigs are very weak in terms of security, and
    Derek> the "forensic trace" argument is close to being moot.

I don't think anybody seriously thinks that inode sigs are useful
against an intentional attack.  I apologize for mistaking this as a
deliberate strawman, but it sure looked that way to me at the time.

    Derek> Having said that, inode sigs are good ways to detect
    Derek> _unintentional_ corruption; and in this case rm -rf (if
    Derek> made atomic) is the reasonable thing to do.

I disagree.  The only case where rm -rf is reasonable is in the case
where the content is not corrupt but there's no simple way to resnap
the inodes.  I think it's reasonable for you to want this, but if Stefan's
idea about resnapping the links works, wouldn't that be even better?

If the content is corrupt, you always want to know why.  Maybe most of
the time the answer is trivial (a link-unsnapping editor) or it isn't
worth the effort for most people to actually look and find out.  But
tla should _never_ presume to make that judgment.  It should preserve
the information until explicitly told to destroy it.

It's the same reasons that fsck links all the junk inodes and blocks
into lost+found, etc.  That has saved my butt once (well, 1 hour of
poking around in lost+found saved me 3 weeks wait for reordering the
data set from the vendor), although over the years I've probably had
several thousand objects end up in lost+found.  The analogy is not
exact, of course, but I bet there would be the occasional person who
really regretted tla removing corrupt revlibs automatically.

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