From: Jarek Poplawski <jarkao2@gmail•com>
To: Jann Traschewski <jann@gmx•de>
Cc: Ralf Baechle <ralf@linux-mips•org>, netdev@vger•kernel.org
Subject: [BUG][AX25] Fwd: SMP with AX.25
Date: Wed, 6 Feb 2008 09:30:50 +0000 [thread overview]
Message-ID: <20080206093050.GF4496@ff.dom.local> (raw)
In-Reply-To: <20080206074529.GC4496@ff.dom.local>
On Wed, Feb 06, 2008 at 07:45:29AM +0000, Jarek Poplawski wrote:
...
> From: Jann Traschewski <jann@gmx•de>
> Subject: SMP with AX.25
> To: jarkao2@gmail•com
According to one of OOPSes reported by Jann softirq can break
while skb is prepared for netif_rx. The report isn't complete,
so the real reason of the later bug could be different, but
IMHO this locking in ax_bump is wrong.
I attach this patch for testing purpose only.
Jarek P.
---
drivers/net/hamradio/mkiss.c | 5 ++---
1 files changed, 2 insertions(+), 3 deletions(-)
diff --git a/drivers/net/hamradio/mkiss.c b/drivers/net/hamradio/mkiss.c
index cfcd15a..30c9b3b 100644
--- a/drivers/net/hamradio/mkiss.c
+++ b/drivers/net/hamradio/mkiss.c
@@ -289,7 +289,6 @@ static void ax_bump(struct mkiss *ax)
*ax->rbuff &= ~0x20;
}
}
- spin_unlock_bh(&ax->buflock);
count = ax->rcount;
@@ -297,17 +296,17 @@ static void ax_bump(struct mkiss *ax)
printk(KERN_ERR "mkiss: %s: memory squeeze, dropping packet.\n",
ax->dev->name);
ax->stats.rx_dropped++;
+ spin_unlock_bh(&ax->buflock);
return;
}
- spin_lock_bh(&ax->buflock);
memcpy(skb_put(skb,count), ax->rbuff, count);
- spin_unlock_bh(&ax->buflock);
skb->protocol = ax25_type_trans(skb, ax->dev);
netif_rx(skb);
ax->dev->last_rx = jiffies;
ax->stats.rx_packets++;
ax->stats.rx_bytes += count;
+ spin_unlock_bh(&ax->buflock);
}
static void kiss_unesc(struct mkiss *ax, unsigned char s)
next prev parent reply other threads:[~2008-02-06 9:23 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <00f201c8694a$2770f630$453c822c@dg8ngn>
[not found] ` <cd9157050802071100m76a742bbyb18f4448d8ec436b@mail.gmail.com>
2008-02-06 7:45 ` [BUG][AX25] Fwd: SMP with AX.25 Jarek Poplawski
2008-02-06 8:15 ` [PATCH][AX25] " Jarek Poplawski
2008-02-06 9:14 ` [PATCH][AX25] ax25_ds_timer: use mod_timer instead of add_timer Jarek Poplawski
2008-02-10 18:23 ` Jann Traschewski
2008-02-12 5:38 ` David Miller
2008-02-12 5:37 ` [PATCH][AX25] Fwd: SMP with AX.25 David Miller
2008-02-06 9:30 ` Jarek Poplawski [this message]
2008-02-07 12:07 ` [BUG][AX25] " Jarek Poplawski
2008-02-07 19:34 ` Jarek Poplawski
2008-02-07 19:35 ` Jarek Poplawski
2008-02-07 20:34 ` Jarek Poplawski
2008-02-13 11:17 ` [PATCH][AX25] mkiss: ax_bump() locking fix Jarek Poplawski
2008-02-15 15:53 ` Jeff Garzik
2008-02-13 11:56 ` [PATCH][AX25] ax25_out: check skb for NULL in ax25_kick() Jarek Poplawski
2008-02-14 0:49 ` Jann Traschewski
2008-03-09 9:02 ` Pidoux
2008-03-09 14:30 ` Jarek Poplawski
2008-03-09 17:34 ` Jann Traschewski
2008-03-09 18:03 ` Jarek Poplawski
2008-03-24 5:03 ` David Miller
2008-02-18 6:31 ` David Miller
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