netdev - Re: [PATCH 3/3] net: hisilicon: new hip04 ethernet driver

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]

Date:	Mon, 24 Mar 2014 10:35:49 -0700
From:	Florian Fainelli <f.fainelli@...il.com>
To:	Arnd Bergmann <arnd@...db.de>
Cc:	Mark Rutland <mark.rutland@....com>,
	"devicetree@...r.kernel.org" <devicetree@...r.kernel.org>,
	Russell King <linux@....linux.org.uk>,
	Sergei Shtylyov <sergei.shtylyov@...entembedded.com>,
	netdev <netdev@...r.kernel.org>,
	Zhangfei Gao <zhangfei.gao@...aro.org>,
	David Miller <davem@...emloft.net>,
	"linux-arm-kernel@...ts.infradead.org" 
	<linux-arm-kernel@...ts.infradead.org>
Subject: Re: [PATCH 3/3] net: hisilicon: new hip04 ethernet driver

2014-03-24 10:23 GMT-07:00 Arnd Bergmann <arnd@...db.de>:
> On Monday 24 March 2014 09:32:17 Florian Fainelli wrote:
>> > +       priv->tx_skb[tx_head] = skb;
>> > +       priv->tx_phys[tx_head] = phys;
>> > +       desc->send_addr = cpu_to_be32(phys);
>> > +       desc->send_size = cpu_to_be16(skb->len);
>> > +       desc->cfg = cpu_to_be32(DESC_DEF_CFG);
>> > +       phys = priv->tx_desc_dma + tx_head * sizeof(struct tx_desc);
>> > +       desc->wb_addr = cpu_to_be32(phys);
>>
>> Don't we need a barrier here to ensure that all stores are completed
>> before we hand this descriptor address to hip40_set_xmit_desc() which
>> should make DMA start processing it?
>
> I would think the writel() in set_xmit_desc() implies the barrier.

Right, which means that this should be properly documented to make
sure that this simplification is well understood and produces the
expected result.
-- 
Florian
--
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