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I can successfully add libata.ignore_hpa=1 to my boot command and the following cmd will yield a '1' upon boot:

cat /sys/module/libata/parameters/ignore_hpa

but grep'ing sysctl -a for libata and attempting sysctl -w libata.ignore_hpa=1result in failure.

How can a param be added to boot-command but not accepted by sysctl??


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There's two different interfaces for accessing and controlling module information. /sys uses the interfaces exposed my sysfs, but this is - actually - not what is controlled by sysctl. The latter accesses stuff under /proc/sys.

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