linux-hams.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Yang Yingliang <yangyingliang@huawei.com>
To: netdev@vger.kernel.org
Cc: davem@davemloft.net, edumazet@google.com, kuba@kernel.org,
	pabeni@redhat.com, leon@kernel.org,
	Yang Yingliang <yangyingliang@huawei.com>,
	Joerg Reuter <jreuter@yaina.de>,
	linux-hams@vger.kernel.org
Subject: [PATCH net v3 3/4] hamradio: don't call dev_kfree_skb() under spin_lock_irqsave()
Date: Thu, 8 Dec 2022 22:21:46 +0800	[thread overview]
Message-ID: <20221208142147.2376671-4-yangyingliang@huawei.com> (raw)
In-Reply-To: <20221208142147.2376671-1-yangyingliang@huawei.com>

It is not allowed to call kfree_skb() or consume_skb() from hardware
interrupt context or with hardware interrupts being disabled.

It should use dev_kfree_skb_irq() or dev_consume_skb_irq() instead.
The difference between them is free reason, dev_kfree_skb_irq() means
the SKB is dropped in error and dev_consume_skb_irq() means the SKB
is consumed in normal.

In scc_discard_buffers(), dev_kfree_skb() is called to discard the SKBs,
so replace it with dev_kfree_skb_irq().

In scc_net_tx(), dev_kfree_skb() is called to drop the SKB that exceed
queue length, so replace it with dev_kfree_skb_irq().

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
---
 drivers/net/hamradio/scc.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/hamradio/scc.c b/drivers/net/hamradio/scc.c
index f90830d3dfa6..bd80e8ca6c79 100644
--- a/drivers/net/hamradio/scc.c
+++ b/drivers/net/hamradio/scc.c
@@ -302,12 +302,12 @@ static inline void scc_discard_buffers(struct scc_channel *scc)
 	spin_lock_irqsave(&scc->lock, flags);	
 	if (scc->tx_buff != NULL)
 	{
-		dev_kfree_skb(scc->tx_buff);
+		dev_kfree_skb_irq(scc->tx_buff);
 		scc->tx_buff = NULL;
 	}
 	
 	while (!skb_queue_empty(&scc->tx_queue))
-		dev_kfree_skb(skb_dequeue(&scc->tx_queue));
+		dev_kfree_skb_irq(skb_dequeue(&scc->tx_queue));
 
 	spin_unlock_irqrestore(&scc->lock, flags);
 }
@@ -1668,7 +1668,7 @@ static netdev_tx_t scc_net_tx(struct sk_buff *skb, struct net_device *dev)
 	if (skb_queue_len(&scc->tx_queue) > scc->dev->tx_queue_len) {
 		struct sk_buff *skb_del;
 		skb_del = skb_dequeue(&scc->tx_queue);
-		dev_kfree_skb(skb_del);
+		dev_kfree_skb_irq(skb_del);
 	}
 	skb_queue_tail(&scc->tx_queue, skb);
 	netif_trans_update(dev);
-- 
2.25.1


  reply	other threads:[~2022-12-08 14:21 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-12-08 14:21 [PATCH net v3 0/4] net: don't call dev_kfree_skb() under spin_lock_irqsave() Yang Yingliang
2022-12-08 14:21 ` Yang Yingliang [this message]
2022-12-12 10:10 ` patchwork-bot+netdevbpf

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20221208142147.2376671-4-yangyingliang@huawei.com \
    --to=yangyingliang@huawei.com \
    --cc=davem@davemloft.net \
    --cc=edumazet@google.com \
    --cc=jreuter@yaina.de \
    --cc=kuba@kernel.org \
    --cc=leon@kernel.org \
    --cc=linux-hams@vger.kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=pabeni@redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).