Created attachment 215231 [details]
Patch for disk_open()
From FreeBSD 12.1 till current version of FreeBSD. userboot.so loader haves issue with raw BSD partitions directly on disk without any PC slice schema aka MBR or GPT.
Bug came after commit, when predefine constant values was replaced with macro definitions in userboot/main.c and common/disk.c. These two members of devsw structure d_slice and d_partition now have defined constants. One of them have different value from previous version of code.
D_PARTWILD now have value -2, before that change dev.d_partition has 0.
I didn't take easy step directly to change macro D_PARTWILD to 0, because I saw that uboot loader already used this macro.
I made patch in common/disk.c file into disk_open() function