linux-kernel - Re: [PATCH V4 2/4] net-next: mediatek: add support for MT7623 ethernet

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]

Date:	Mon, 07 Mar 2016 11:30:54 -0500 (EST)
From:	David Miller <davem@...emloft.net>
To:	blogic@...nwrt.org
Cc:	linux-kernel@...r.kernel.org, netdev@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org,
	linux-mediatek@...ts.infradead.org, steven.liu@...iatek.com,
	Carlos.Huang@...iatek.com, nbd@...nwrt.org, igvtee@...il.com
Subject: Re: [PATCH V4 2/4] net-next: mediatek: add support for MT7623
 ethernet

From: John Crispin <blogic@...nwrt.org>
Date: Mon,  7 Mar 2016 09:56:35 +0100

> +static int mtk_mdio_busy_wait(struct mtk_eth *eth)
> +{
> +	unsigned long t_start = jiffies;
> +
> +	while (1) {
> +		if (!(mtk_r32(eth, MTK_PHY_IAC) & PHY_IAC_ACCESS))
> +			return 0;
> +		if (time_after(jiffies, t_start + PHY_IAC_TIMEOUT))
> +			break;
> +	}
> +
> +	dev_err(eth->dev, "mdio: MDIO timeout\n");
> +	return -1;
> +}

Busy polling in a loop for up to 5 seconds with no preemption points
is not something you can do, sorry.