Hello,
My static analysis tool reports a possible ABBA deadlock in the hfi1
driver in Linux 5.10:
sc_disable()
write_seqlock(&sc->waitlock); --> Line 956 (Lock A)
hfi1_qp_wakeup()
spin_lock_irqsave(&qp->s_lock, flags); --> Line 441 (Lock B)
pio_wait()
spin_lock_irqsave(&qp->s_lock, flags); --> Line 939 (Lock B)
write_seqlock(&sc->waitlock); --> Line 941 (Lock A)
When sc_disable() and pio_wait() are concurrently executed, the deadlock
can occur.
I am not quite sure whether this possible deadlock is real and how to
fix it if it is real.
Any feedback would be appreciated, thanks :)
Reported-by: TOTE Robot <oslab@xxxxxxxxxxxxxxx>
Best wishes,
Jia-Ju Bai
