linux-kernel - [PATCH net] gianfar: Fix boot hangs while bringing up gianfar 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] [thread-next>] [day] [month] [year] [list]

Message-ID: <20090209193440.GA2537@ami.dom.local>
Date:	Mon, 9 Feb 2009 20:34:40 +0100
From:	Jarek Poplawski <jarkao2@...il.com>
To:	Jeff Garzik <jeff@...zik.org>, David Miller <davem@...emloft.net>
Cc:	Ira Snyder <iws@...o.caltech.edu>,
	Peter Korsgaard <jacmet@...site.dk>,
	Dai Haruki <dai.haruki@...escale.com>,
	Andy Fleming <afleming@...escale.com>,
	linux-kernel@...r.kernel.org, netdev@...r.kernel.org
Subject: [PATCH net] gianfar: Fix boot hangs while bringing up gianfar
	ethernet

On Mon, Feb 09, 2009 at 09:22:17AM -0800, Ira Snyder wrote:
...
> It works fine for me, the board now boots up normally.
> 
> Thanks for the patch,
> Ira

Very nice! Here is the same plus a comment. 

Many thanks,
Jarek P.

PS: Ira, your mta config is a bit unusual here wrt. reply; I hope you
will forgive me adding you to CC anyway.

PS#2: Andy, this changelog is really a lot harder than the patch...

------------------->
gianfar: Fix boot hangs while bringing up gianfar ethernet

Ira Snyder found that commit 8c7396aebb68994c0519e438eecdf4d5fa9c7844
"gianfar: Merge Tx and Rx interrupt for scheduling clean up ring" can
cause hangs. It's because there was removed clearing of interrupts in
gfar_schedule_cleanup() (which is called by an interrupt handler) in
case when netif scheduling has been disabled. This patch brings back
this action and a comment.

Reported-by: Ira Snyder <iws@...o.caltech.edu>
Reported-by: Peter Korsgaard <jacmet@...site.dk>
Bisected-by: Ira Snyder <iws@...o.caltech.edu>
Tested-by: Peter Korsgaard <jacmet@...site.dk>
Tested-by: Ira Snyder <iws@...o.caltech.edu>
Signed-by: Jarek Poplawski <jarkao2@...il.com>

---

 drivers/net/gianfar.c |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/drivers/net/gianfar.c b/drivers/net/gianfar.c
index acae2d8..9b12a13 100644
--- a/drivers/net/gianfar.c
+++ b/drivers/net/gianfar.c
@@ -1629,6 +1629,12 @@ static void gfar_schedule_cleanup(struct net_device *dev)
 	if (netif_rx_schedule_prep(&priv->napi)) {
 		gfar_write(&priv->regs->imask, IMASK_RTX_DISABLED);
 		__netif_rx_schedule(&priv->napi);
+	} else {
+		/*
+		 * Clear IEVENT, so interrupts aren't called again
+		 * because of the packets that have already arrived.
+		 */
+		gfar_write(&priv->regs->ievent, IEVENT_RTX_MASK);
 	}
 
 	spin_unlock(&priv->rxlock);
--
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/