Comment 0 for bug 1742696

New bug forked out of Bug #1734147 "corrupted BIOS due to Intel SPI bug in kernel Edit"

When trying to apply the proposed fix in Bug #1734147 to a Lenovo Yoga with Serial Flash s25fl064k, the actual fix works, however reverting back to original available Kernel <4.14.x again locks the BIOS for write.

How to identify chip: Using the Fix Kernel from Bug #1734147 the kernel log will show intel-spi entries.
In lower part serial is shown as below:

intel-spi intel-spi: s25fl064k (8192 Kbytes)

Additional Information:
Lenovo Yoga running Linux Mint 18.3 (based on Xenial 16.04)
Bug #1734147 occured when trying Ubuntu 17.10

Explanation by Mika Westerberg (Bug #1734147, Comment #524)
"commit d9018976cdb6 is missing with this particular BIOS/system because every time you boot the system, the BIOS resets to default when it finds BCR register is changed. This is different issue than the CMP=1 issue most of the users have reported. This one also is not permanent so everything is fine as long as you don't touch that BCR register. In this case you either need to always boot to a kernel where that fix (d9018976cdb6) is included or blacklist lpc_ich.ko. Ubuntu v4.14.x kernels have that fix included so you might want to take one of them or build your own."

New bug requested to discuss this separate from main Bug #1734147
Anthony Wong (Bug #1734147, Comment #525)
"Looks like we need to cherry-pick it to 4.13 after all.
Christian, do you mind opening a new bug for your issue? We should continue the discussion and fix over there."