netdev - Re: [PATCH RFX]: napi

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] [day] [month] [year] [list]

Message-Id: <20070728.223049.78711264.davem@davemloft.net>
Date:	Sat, 28 Jul 2007 22:30:49 -0700 (PDT)
From:	David Miller <davem@...emloft.net>
To:	rdreier@...co.com
Cc:	netdev@...r.kernel.org, shemminger@...ux-foundation.org,
	rusty@...tcorp.com.au, jgarzik@...ox.com
Subject: Re: [PATCH RFX]: napi_struct V3

From: Roland Dreier <rdreier@...co.com>
Date: Sat, 28 Jul 2007 08:21:58 -0700

>  > Another area of consternation are drivers that were using
>  > netif_rx_reschedule(), as that interface was removed because it
>  > doesn't fit well with the caller managing the dev->quota et al.  I
>  > left race conditions in the drivers that were using that interface,
>  > but they should still basically work nonetheless.
> 
> ...but this is a problem for IPoIB.  The underlying IB stuff only
> allows us to register what is essentially a one-shot edge-triggered
> interrupt.  So there is a race between calling netif_rx_complete() and
> calling ib_req_notify_cq() (which enables the interrupt), since the
> interrupt might never happen if a packet arrives between the two calls.

You will see further along in the thread that we have found
a locking sequence by which this issue can be resolved.

Please read the full thread and the most recent patch before
coming to conclusions :-)
-
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