linux-kernel - Re: Revert "gro: Fix legacy path 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] [thread-next>] [day] [month] [year] [list]

Message-Id: <20090324.190914.117958201.davem@davemloft.net>
Date:	Tue, 24 Mar 2009 19:09:14 -0700 (PDT)
From:	David Miller <davem@...emloft.net>
To:	herbert@...dor.apana.org.au
Cc:	mingo@...e.hu, r.schwebel@...gutronix.de,
	torvalds@...ux-foundation.org, blaschka@...ux.vnet.ibm.com,
	tglx@...utronix.de, a.p.zijlstra@...llo.nl,
	linux-kernel@...r.kernel.org, kernel@...gutronix.de
Subject: Re: Revert "gro: Fix legacy path napi_complete crash",

From: Herbert Xu <herbert@...dor.apana.org.au>
Date: Wed, 25 Mar 2009 08:32:35 +0800

> On Tue, Mar 24, 2009 at 05:02:41PM +0100, Ingo Molnar wrote:
> > 
> > * Herbert Xu <herbert@...dor.apana.org.au> wrote:
> >
> > > What's the NIC and config on this one? If it's still using the 
> > > legacy/netif_rx path, where GRO is off by default, this patch 
> > > should make it exactly the same as with my original patch 
> > > reverted.
> > 
> > Same forcedeth box i reported before. Config below. (note: if you 
> > want to use it you need to run it through 'make oldconfig', with all 
> > defaults accepted)
> >
> > CONFIG_FORCEDETH=y
> > CONFIG_FORCEDETH_NAPI=y
> 
> This means that we shouldn't even invoke netif_rx/process_backlog,
> so something else is going on.

There is always loopback which does netif_rx().

Combine that with the straight NAPI receive that forcedeth
is doing here and I'm sure there are all kinds of race
scenerios possible :-)

You're right about GRO not being relevant here.  To be honest
I wouldn't be disappointed if GRO was simply on by default
even for the legacy paths.
--
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/