PS

*hll - to be imbecile, weak-minded, mad; be mocked at (SED I No. 19ᵥ)

Originally rather a biconsonantal stem. Note various ways of triconsonantization in Eth. and a full reduplication in Arb. and Soq.

Akkadian
ulālu - weakling (CAD U–W 69, AHw. 1407)
Hebrew
hll - to be infatuated; to make look foolish; (po.) to make a mockery of; (hitpo.) to pretend to be mad; to act like a madman (HALOT 249)
Hebrew
hōlēlūt - foolishness, blindness (HALOT 242)
Syriac
hll - (aph.) to scoff, mock; to despise, disdain; to praise (LSyr. 176, SL 344)
Arabic
halhal - injure; sottise (DRS 411)
Arabic
wahl- - opinion, idée fausse qu'on se fait sur quelque chose (opinion, misconception we have about something) (BK 2 1616)
May be related as a root variant.
Geez
hawlaya - to ridicule, mock, make fun of, jeer at (CDG 220)
Also ḥawlaya.
Tigre
haläwläw - foolish (WTS 4)
Partial reduplication.
Amharic
allälä - to be in heat (equines); to desire sex (AED 1102)
Semanically possible, but hard to prove.
Soddo
wällät - foolish, imbecile (EDG 653)
Soqotri
hálhal - bête, idiot (LS 143)
Full reduplication.