From: Niels Dossche dossche.niels@gmail.com
[ Upstream commit 22cbc6c2681a0a4fe76150270426e763d52353a4 ]
The documentation of the function rvt_error_qp says both r_lock and s_lock need to be held when calling that function. It also asserts using lockdep that both of those locks are held. rvt_error_qp is called form rvt_send_cq, which is called from rvt_qp_complete_swqe, which is called from rvt_send_complete, which is called from rvt_ruc_loopback in two places. Both of these places do not hold r_lock. Fix this by acquiring a spin_lock of r_lock in both of these places. The r_lock acquiring cannot be added in rvt_qp_complete_swqe because some of its other callers already have r_lock acquired.
Link: https://lore.kernel.org/r/20220228195144.71946-1-dossche.niels@gmail.com Signed-off-by: Niels Dossche dossche.niels@gmail.com Signed-off-by: Jason Gunthorpe jgg@nvidia.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/infiniband/sw/rdmavt/qp.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/infiniband/sw/rdmavt/qp.c b/drivers/infiniband/sw/rdmavt/qp.c index 8ef112f883a7..3acab569fbb9 100644 --- a/drivers/infiniband/sw/rdmavt/qp.c +++ b/drivers/infiniband/sw/rdmavt/qp.c @@ -2775,7 +2775,7 @@ void rvt_qp_iter(struct rvt_dev_info *rdi, EXPORT_SYMBOL(rvt_qp_iter);
/* - * This should be called with s_lock held. + * This should be called with s_lock and r_lock held. */ void rvt_send_complete(struct rvt_qp *qp, struct rvt_swqe *wqe, enum ib_wc_status status) @@ -3134,7 +3134,9 @@ void rvt_ruc_loopback(struct rvt_qp *sqp) rvp->n_loop_pkts++; flush_send: sqp->s_rnr_retry = sqp->s_rnr_retry_cnt; + spin_lock(&sqp->r_lock); rvt_send_complete(sqp, wqe, send_status); + spin_unlock(&sqp->r_lock); if (local_ops) { atomic_dec(&sqp->local_ops_pending); local_ops = 0; @@ -3188,7 +3190,9 @@ void rvt_ruc_loopback(struct rvt_qp *sqp) spin_unlock_irqrestore(&qp->r_lock, flags); serr_no_r_lock: spin_lock_irqsave(&sqp->s_lock, flags); + spin_lock(&sqp->r_lock); rvt_send_complete(sqp, wqe, send_status); + spin_unlock(&sqp->r_lock); if (sqp->ibqp.qp_type == IB_QPT_RC) { int lastwqe;