netdev - Re: [PATCH v3] sis900: Fix the tx queue timeout issue

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: <20130802.150400.1854139334376781614.davem@davemloft.net>
Date:	Fri, 02 Aug 2013 15:04:00 -0700 (PDT)
From:	David Miller <davem@...emloft.net>
To:	bhutchings@...arflare.com
Cc:	kda@...ux-powerpc.org, venza@...wnhat.org, B38611@...escale.com,
	netdev@...r.kernel.org
Subject: Re: [PATCH v3] sis900: Fix the tx queue timeout issue

From: Ben Hutchings <bhutchings@...arflare.com>
Date: Fri, 2 Aug 2013 21:18:55 +0200

> This looks reasonable.  It looks like link changes now work like this:
> 
> 1. When sis900_timer() detects link-down, it calls netif_carrier_off()
> but does not clear autong_complete.
> 2. When sis900_timer() detects link-up, it calls sis900_check_mode()
> which restarts autonegotiation and clears autong_complete.
> 3. sis900_timer() will now call sis900_read_mode().  When that detects
> link-up, it sets autong_complete and calls netif_carrier_on().
> 
> This patch has moved the call to netif_carrier_on() from step 2 to step
> 3.  However, I don't understand why autonegotiation is restarted in step
> 2.  When autonegotiation is enabled, the PHY should not indicate link-up
> until it has completed.  Perhaps this is a necessary workaround for a
> hardware bug.  Otherwise it's a waste of time.

Agreed, if the PHY was configured to use autonegotiation, getting a link
up event afterwards implies that autonegotiation is complete.

In any event, I'm going to apply this patch anyways because it is far and
above a significant move forward.
--
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