Where? I'm looking at http://shop.lenovo.com/us/en/laptops/yoga/900-series/yoga-90... and the specs page lists only Windows 10 Home and Pro in the operating systems section.
> and effort was expended specifically to disable that option
Lenovo has issued a formal statement denying it. http://www.techrepublic.com/article/lenovo-denies-deliberate...
I was imprecise. The chipset supports a Linux-compatible option, were it not explicitly disabled in the firmware.
> Lenovo has issued a formal statement denying it.
They deny purposefully disabling Linux, and I don't have any evidence against that denial. They don't deny disabling AHCI, because they clearly did. In the disassembly of the code: https://lnv.i.lithium.com/t5/image/serverpage/image-id/76843...
Intel's RAID is implemented in their driver. Switching the option from AHCI to RAID switches the disk controller's ID so it doesn't bind to the OS's standard driver (whichever OS that is), and binds to Intel's instead (assuming it's present). Intel provides its driver (and only for Windows), Lenovo locks the option so that hapless users mucking about in the UEFI settings don't make their machines unbootable.
Lenovo can deny "deliberately blocking Linux", but they can't deny "practically blocking Linux".
If I buy some hardware, I've done research on whether all of its chipsets and devices have Linux driver support just as a matter of course, because I don't expect that Linux will run on every PC. But I feel like I have a right to know if a company puts a non-standard artificial restriction on their hardware. Apparently in this case, Windows 10 doesn't even have the driver included by default, so I can't even reload the software that the machine was designed to run, on my own. That sounds like a defect in the product, to me.