Link global_asm problem

I wrapped the boot asm code in ‘global_asm’, but when link, I get error:
has non-ABS relocation R_ARM_JUMP24 against symbol ‘_boot’

the ‘_boot’ is a rust function, and used in asm code( for arm) ‘b _boot’ which want jump to call it.

I can’t get any valid info on google, anyone can help?