linux-kernel - Re: [PATCH 2/3] netpoll: rework skb transmit queue

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: <20061020144153.2bbeaf9d@dxpl.pdx.osdl.net>
Date:	Fri, 20 Oct 2006 14:41:53 -0700
From:	Stephen Hemminger <shemminger@...l.org>
To:	Andi Kleen <ak@...e.de>
Cc:	David Miller <davem@...emloft.net>, netdev@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 2/3] netpoll: rework skb transmit queue

On Fri, 20 Oct 2006 23:16:03 +0200
Andi Kleen <ak@...e.de> wrote:

> On Friday 20 October 2006 23:08, David Miller wrote:
> > From: Andi Kleen <ak@...e.de>
> > Date: Fri, 20 Oct 2006 23:01:29 +0200
> > 
> > > netpoll always played a little fast'n'lose with various locking rules.
> > 
> > The current code is fine, it never reenters ->poll, because it
> > maintains a "->poll_owner" which it checks in netpoll_send_skb()
> > before trying to call back into ->poll.
> 
> I was more thinking of reentry of the interrupt handler in 
> the driver etc. A lot of them also do printk, but that is fortunately
> caught higher level.
> 
> -Andi

One problem is that with netconsole the NAPI poll routine can be
called with IRQ's disabled. This means that calls to dev_kfree_skb()
are incorrect in this context. The driver would have to use dev_kfree_skb_any()
instead.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/