nvme: compute number of requested log page words correctly - #1215
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iximeow
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rmustacc
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Sep 11, 2026
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(foo & 0xFFF) >> 16is a rather doomed expression. this fixes the secondary issue I'd noticed in #1213, where log pages seemed to have random data in them from call to call.the field we're trying to extract here is
NUMDLin bits31:16of cdw10. basically all the symbols were right, just.. in the wrong order. the consequence here was that we were computing a log page request for 0 (meaning, 1) dword, and filling in the first four bytes of the request with zero. Linux has been requesting 127 (meaning, 128) dwords the entire time, to fill all 512 bytes of defined-and-reserved space in the log page.I don't know why this goes from being what I observed with garbage data in 22.04, to being zeroed later on. I assume that's a kernel change, since prp1 becomes always-aligned, and I assume that the kernel decides to zero the page to guard against misbehaving devices like ours that don't write all the bits they're supposed to!