netdev - Re: [PATCH] jme: netpoll support

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20120718.202431.2078849403941565725.davem@davemloft.net>
Date:	Wed, 18 Jul 2012 20:24:31 -0700 (PDT)
From:	David Miller <davem@...emloft.net>
To:	cooldavid@...ldavid.org
Cc:	lekensteyn@...il.com, netdev@...r.kernel.org
Subject: Re: [PATCH] jme: netpoll support

From: "Guo-Fu Tseng" <cooldavid@...ldavid.org>
Date: Thu, 19 Jul 2012 10:00:10 +0800

> On Wed, 18 Jul 2012 09:45:24 -0700 (PDT), David Miller wrote
>> From: Lekensteyn <lekensteyn@...il.com>
>> Date: Tue, 17 Jul 2012 18:29:34 +0200
>> 
>> > From: Peter Wu <lekensteyn@...il.com>
>> > 
>> > This patch adds the netpoll function to support netconsole. Tested and works
>> > fine on my "JMC250 PCI Express Gigabit Ethernet Controller" (PCI ID 0250).
>> > 
>> > Signed-off-by: Peter Wu <lekensteyn@...il.com>
>> 
>> Applied to net-next
>> 
>> I really wonder if this driver works on SMP systems at all.
> Hi davem:
> 
> I wrote/tested this driver on SMP system at very beginning.
> In face some of the design was aimed for SMP systems.
> Is there any obvious bug or something I should be aware of?

Well, you do no locking in your IRQ handler.

So how can you be sure in jme_free_irq() during jme_close() that the
handler is not running on some cpu somewhere?

That's why drivers like drivers/net/ethernet/broadcom/tg3.c have
a function like tg3_irq_quiesce(), to guarentee that no code path
is executing in the interrupt handler.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html