FAILED: patch "[PATCH] s390/qeth: schedule TX NAPI on QAOB completion" failed to apply to 5.4-stable tree
From: <gregkh@linuxfoundation.org>
Date: 2021-03-12 12:56:02
Subsystem:
networking drivers, s390 architecture, s390 network drivers, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Heiko Carstens, Vasily Gorbik, Alexander Gordeev, Alexandra Winter, Aswin Karuvally, Linus Torvalds
The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to [off-list ref].
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 3e83d467a08e25b27c44c885f511624a71c84f7c Mon Sep 17 00:00:00 2001
From: Julian Wiedmann <redacted>
Date: Tue, 9 Mar 2021 17:52:20 +0100
Subject: [PATCH] s390/qeth: schedule TX NAPI on QAOB completion
When a QAOB notifies us that a pending TX buffer has been delivered, the
actual TX completion processing by qeth_tx_complete_pending_bufs()
is done within the context of a TX NAPI instance. We shouldn't rely on
this instance being scheduled by some other TX event, but just do it
ourselves.
qeth_qdio_handle_aob() is called from qeth_poll(), ie. our main NAPI
instance. To avoid touching the TX queue's NAPI instance
before/after it is (un-)registered, reorder the code in qeth_open()
and qeth_stop() accordingly.
Fixes: 0da9581ddb0f ("qeth: exploit asynchronous delivery of storage blocks")
Signed-off-by: Julian Wiedmann <redacted>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index 3763cd6d14f8..d0a56afec028 100644
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c@@ -470,6 +470,7 @@ static void qeth_qdio_handle_aob(struct qeth_card *card, struct qaob *aob; struct qeth_qdio_out_buffer *buffer; enum iucv_tx_notify notification; + struct qeth_qdio_out_q *queue; unsigned int i; aob = (struct qaob *) phys_to_virt(phys_aob_addr);
@@ -512,7 +513,9 @@ static void qeth_qdio_handle_aob(struct qeth_card *card, buffer->is_header[i] = 0; } + queue = buffer->q; atomic_set(&buffer->state, QETH_QDIO_BUF_EMPTY); + napi_schedule(&queue->napi); break; default: WARN_ON_ONCE(1);
@@ -7235,9 +7238,7 @@ int qeth_open(struct net_device *dev) card->data.state = CH_STATE_UP; netif_tx_start_all_queues(dev); - napi_enable(&card->napi); local_bh_disable(); - napi_schedule(&card->napi); if (IS_IQD(card)) { struct qeth_qdio_out_q *queue; unsigned int i;
@@ -7249,8 +7250,12 @@ int qeth_open(struct net_device *dev) napi_schedule(&queue->napi); } } + + napi_enable(&card->napi); + napi_schedule(&card->napi); /* kick-start the NAPI softirq: */ local_bh_enable(); + return 0; } EXPORT_SYMBOL_GPL(qeth_open);
@@ -7260,6 +7265,11 @@ int qeth_stop(struct net_device *dev) struct qeth_card *card = dev->ml_priv; QETH_CARD_TEXT(card, 4, "qethstop"); + + napi_disable(&card->napi); + cancel_delayed_work_sync(&card->buffer_reclaim_work); + qdio_stop_irq(CARD_DDEV(card)); + if (IS_IQD(card)) { struct qeth_qdio_out_q *queue; unsigned int i;
@@ -7280,10 +7290,6 @@ int qeth_stop(struct net_device *dev) netif_tx_disable(dev); } - napi_disable(&card->napi); - cancel_delayed_work_sync(&card->buffer_reclaim_work); - qdio_stop_irq(CARD_DDEV(card)); - return 0; } EXPORT_SYMBOL_GPL(qeth_stop);