They are not stock. Knoppix 3.7 kernels are patched with cloop. Knoppix 3.8.x & up are patched with unionfs & cloop. Seek the source code from Klaus Knopper at Knoper.net .
I'd like to know if the kernels in Knoppix 3.7 and Knoppix 3.9 are stock kernels (from kernel.org) or if they are patched. If so which patches were applied ?
They are not stock. Knoppix 3.7 kernels are patched with cloop. Knoppix 3.8.x & up are patched with unionfs & cloop. Seek the source code from Klaus Knopper at Knoper.net .
IMHO cloop and unionfs compiled as standalone modules it not requres pathes for kernel.
Immaterial patch for linux 2.4.* located at /usr/src, but in Knoppix 3.8 it obsoletted

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