On 10/20/22 9:37 AM, Jia-Ju Bai wrote: > Hello, > > My static analysis tool reports several possible ABBA deadlock in the > rdmavt driver in Linux 5.18: > > rvt_ruc_loopback() > spin_lock_irqsave(&sqp->s_lock, flags); --> Line 3190 (Lock A) > spin_lock(&sqp->r_lock); --> Line 3195 (Lock B) > > rvt_qp_mr_clean() > spin_lock_irq(&qp->r_lock); --> Line 698 (Lock B) > spin_lock(&qp->s_lock); --> Line 700 (Lock A) > > rvt_rc_timeout() > spin_lock_irqsave(&qp->r_lock, flags); --> Line 2595 (Lock B) > spin_lock(&qp->s_lock); --> Line 2596 (Lock A) > > rvt_modify_qp() > spin_lock_irq(&qp->r_lock); --> Line 1419 (Lock B) > spin_lock(&qp->s_lock); --> Line 1421(Lock A) > > _rvt_reset_qp() > spin_lock_irq(&qp->r_lock); --> Line 907 (Lock B) > spin_lock(&qp->s_lock); --> Line 909 (Lock A) > > rvt_reset_qp() > spin_lock_irq(&qp->r_lock); --> Line 936 (Lock B) > spin_lock(&qp->s_lock); --> Line 938 (Lock A) > > When rvt_ruc_loopback() is concurrently executed with rvt_qp_mr_clean(), > rvt_rc_timeout(), rvt_modify_qp(), _rvt_reset_qp() or rvt_reset_qp(), > the deadlocks can occur. > > I am not quite sure whether these possible deadlocks are real and how to > fix them if real. > Any feedback would be appreciated, thanks :) > > Reported-by: TOTE Robot <oslab@xxxxxxxxxxxxxxx> Thanks, we'll look into them. -Denny
