On Thu, Mar 12, 2026 at 07:08:16PM -0400, Yury Norov wrote: > Based on 'sizeof(x) == 4' condition, in 32-bit case the function is wired > to ffs(), while in 64-bit case to __ffs(). The difference is substantial: > ffs(x) == __ffs(x) + 1. Also, ffs(0) == 0, while __ffs(0) is undefined. > > The 32-bit behaviour is inconsistent with the function description, so it > needs to get fixed. > > There are 9 individual users for the function in 6 different subsystems. > Some arches and drivers are 64-bit only: > - arch/loongarch/kvm/intc/eiointc.c; > - drivers/hv/mshv_vtl_main.c; > - kernel/liveupdate/kexec_handover.c; > > The others are: > - ib_umem_find_best_pgsz(): as per comment, __ffs() should be correct;
So long as 32 bit works the same as 64 bit it is correct for ib Jason
