This is a note to let you know that I've just added the patch titled

iw_cxgb4: only clear the ARMED bit if a notification is needed

to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: iw_cxgb4-only-clear-the-armed-bit-if-a-notification-is-needed.patch and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From 335ebf6fa35ca1c59b73f76fad19b249d3550e86 Mon Sep 17 00:00:00 2001

From: Steve Wise swise@opengridcomputing.com Date: Thu, 30 Nov 2017 09:41:56 -0800 Subject: iw_cxgb4: only clear the ARMED bit if a notification is needed

From: Steve Wise swise@opengridcomputing.com

commit 335ebf6fa35ca1c59b73f76fad19b249d3550e86 upstream.

In __flush_qp(), the CQ ARMED bit was being cleared regardless of whether any notification is actually needed. This resulted in the iser termination logic getting stuck in ib_drain_sq() because the CQ was not marked ARMED and thus the drain CQE notification wasn't triggered.

This new bug was exposed when this commit was merged:

commit cbb40fadd31c ("iw_cxgb4: only call the cq comp_handler when the cq is armed")

Signed-off-by: Steve Wise swise@opengridcomputing.com Signed-off-by: Jason Gunthorpe jgg@mellanox.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- drivers/infiniband/hw/cxgb4/qp.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)

--- a/drivers/infiniband/hw/cxgb4/qp.c +++ b/drivers/infiniband/hw/cxgb4/qp.c @@ -1301,21 +1301,21 @@ static void __flush_qp(struct c4iw_qp *q spin_unlock_irqrestore(&rchp->lock, flag);

if (schp == rchp) { - if (t4_clear_cq_armed(&rchp->cq) && - (rq_flushed || sq_flushed)) { + if ((rq_flushed || sq_flushed) && + t4_clear_cq_armed(&rchp->cq)) { spin_lock_irqsave(&rchp->comp_handler_lock, flag); (*rchp->ibcq.comp_handler)(&rchp->ibcq, rchp->ibcq.cq_context); spin_unlock_irqrestore(&rchp->comp_handler_lock, flag); } } else { - if (t4_clear_cq_armed(&rchp->cq) && rq_flushed) { + if (rq_flushed && t4_clear_cq_armed(&rchp->cq)) { spin_lock_irqsave(&rchp->comp_handler_lock, flag); (*rchp->ibcq.comp_handler)(&rchp->ibcq, rchp->ibcq.cq_context); spin_unlock_irqrestore(&rchp->comp_handler_lock, flag); } - if (t4_clear_cq_armed(&schp->cq) && sq_flushed) { + if (sq_flushed && t4_clear_cq_armed(&schp->cq)) { spin_lock_irqsave(&schp->comp_handler_lock, flag); (*schp->ibcq.comp_handler)(&schp->ibcq, schp->ibcq.cq_context);

Patches currently in stable-queue which might be from swise@opengridcomputing.com are

queue-4.14/iw_cxgb4-only-clear-the-armed-bit-if-a-notification-is-needed.patch queue-4.14/iw_cxgb4-atomically-flush-the-qp.patch queue-4.14/iw_cxgb4-when-flushing-complete-all-wrs-in-a-chain.patch queue-4.14/iw_cxgb4-reflect-the-original-wr-opcode-in-drain-cqes.patch queue-4.14/iw_cxgb4-only-call-the-cq-comp_handler-when-the-cq-is-armed.patch