(Off list, please keep me in CC, thx!) Hi there, TL;DR: https://github.com/neilbrown/mdadm/commit611d95290dd41d73bd8f9cc06f7ec293a40b819e regresses mdadm and does not let me assemble my main drive due to kernel error
md: invalid array_size 125035870 > default size 125035776 caused by changed reservation size in mdadm, and thus reduced "Usable Size" being reduced too much (smaller than 0.5 * Array Size). Full write-up with logs etc here: https://forum.manjaro.org/t/mdadm-issues-live-cd-works-existing-install-breaks-fakeraid-imsm/93613 I chased through both 4.0 mdadm (which works, e.g., from a Live image), and the new 4.1 version (from Manjaro update), and the same disk in the same machine works with the older, and refuses to work with the newer mdadm. The kernel message suggests that the kernel refuses to assemble the array, and tracing the computation back through both versions (4.0 and GIT head 3c9b46cf9ae15a9be98fc47e2080bd9494496246 ) reveals that both versions end up using the default for reserved space, which is MPB_SECTOR_CNT + IMSM_RESERVED_SECTORS (the other difference between the versions is the size computed, but that is hopefully intentional due to 444909385fdaccf961308c4319d7029b82bf8bb1 ). I understand too little to propose a fix or know why the defaults were changed, but this is clearly a regression, and the disk works in the same machine in Windows, and with older Live images. More log output in the Manjaro forum thread, and I have some more log output with printf's sprinkled around if necessary. Happy to help fix this, please have a look :) Thanks, Stephan
