Yup saw the same thing:
(1957867653*1024)/1024/1024/1024/1024 = 1.82T
I'm afraid you don't have a truncated filesystem, you have a truncated
block device. I'm afraid this is not an xfs problem... you need to
figure out what happened to sdc1 (for example, why doesn't it extend to
the end of sdc?)
-Eric
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