netdev - Re: [PATCH] net: mvmdio: fix interrupt timeout handling

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: <52B2D97F.4070200@gmail.com>
Date:	Thu, 19 Dec 2013 12:33:19 +0100
From:	Sebastian Hesselbarth <sebastian.hesselbarth@...il.com>
To:	Leigh Brown <leigh@...inno.co.uk>,
	"David S. Miller" <davem@...emloft.net>
CC:	Nicolas Schichan <nschichan@...ebox.fr>,
	Russell King - ARM Linux <linux@....linux.org.uk>,
	Jason Cooper <jason@...edaemon.net>, netdev@...r.kernel.org,
	LKML <linux-kernel@...r.kernel.org>,
	Florian Fainelli <florian@...nwrt.org>,
	linux-arm-kernel@...ts.infradead.org
Subject: Re: [PATCH] net: mvmdio: fix interrupt timeout handling

On 12/19/13 12:13, Leigh Brown wrote:
> orion_mdio_wait_ready uses wait_event_timeout to wait for the
> SMI interrupt to fire.  wait_event_timeout waits for between
> "timeout - 1" and "timeout" jiffies.  In this case a 1ms timeout
> when HZ is 1000 results in a wait of 0 to 1 jiffies, causing
> premature timeouts.
>
> This fix ensures a minimum timeout of 2 jiffies, ensuring
> wait_event_timeout will always wait at least 1 jiffie.
>
> Issue reported by Nicolas Schichan.
>
> Tested-by: Nicolas Schichan <nschichan@...ebox.fr>
> Signed-off-by: Leigh Brown <leigh@...inno.co.uk>
> ---
>   drivers/net/ethernet/marvell/mvmdio.c | 6 ++++++
>   1 file changed, 6 insertions(+)
>
> diff --git a/drivers/net/ethernet/marvell/mvmdio.c b/drivers/net/ethernet/marvell/mvmdio.c
> index 7354960..a42a750 100644
> --- a/drivers/net/ethernet/marvell/mvmdio.c
> +++ b/drivers/net/ethernet/marvell/mvmdio.c
> @@ -92,6 +92,12 @@ static int orion_mdio_wait_ready(struct mii_bus *bus)
>   			if (time_is_before_jiffies(end))
>   				++timedout;
>   	        } else {
> +			/* wait_event_timeout does not guarantee a delay of at
> +			 * least one whole jiffie, so timeout must be no less
> +			 * than two.
> +			 */
> +			 if (timeout < 2)
> +			 	timeout = 2;

Hi Leigh,

above two lines have a whitespace issue.

Sebastian

>   			wait_event_timeout(dev->smi_busy_wait,
>   				           orion_mdio_smi_is_done(dev),
>   				           timeout);
>

--
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