This patch seems to solve the problem.
I removed (and inserted) the module twice without any oopses or panics
or hangs in general.
On Wed, May 30, 2007 at 08:28:09AM -0500, Jason Wessel wrote:
>
> Attached is a patch to fix the soft lockup problem when removing the
> netconsole module.
>
> It looks different than the original patch I posted because the context had
> to change to maintain 80 column code. For reference the original e-mail +
> patch was "[BUG] 2.6.21 hang in cancel_rearming_delayed_workqueue()" sent
> on 5/25/07.
>
> Jason.
>
>
> >From 102a018d601e954f658d272d4daeef139ae40e0e Mon Sep 17 00:00:00 2001
> From: Jason Wessel <[EMAIL PROTECTED]>
> Date: Wed, 30 May 2007 08:03:52 -0500
> Subject: [PATCH] The netpoll_cleanup handler can hang the kernel if there is
> no work in
> the work queue because a call to cancel_rearming_delayed_work() with
> no work goes into an infinite loop.
>
> The typical case where this is a problem is on removing a kernel
> module such as the netconsole driver or kgdboe.
>
> To maintain 80 column code, the function had to have one level of braces
> dropped.
>
> Signed-off-by: Jason Wessel <[EMAIL PROTECTED]>
> ---
> net/core/netpoll.c | 36 +++++++++++++++++++-----------------
> 1 files changed, 19 insertions(+), 17 deletions(-)
>
> diff --git a/net/core/netpoll.c b/net/core/netpoll.c
> index 4581ece..28fa50e 100644
> --- a/net/core/netpoll.c
> +++ b/net/core/netpoll.c
> @@ -766,30 +766,32 @@ void netpoll_cleanup(struct netpoll *np)
> struct netpoll_info *npinfo;
> unsigned long flags;
>
> - if (np->dev) {
> - npinfo = np->dev->npinfo;
> - if (npinfo) {
> - if (npinfo->rx_np == np) {
> - spin_lock_irqsave(&npinfo->rx_lock, flags);
> - npinfo->rx_np = NULL;
> - npinfo->rx_flags &= ~NETPOLL_RX_ENABLED;
> - spin_unlock_irqrestore(&npinfo->rx_lock, flags);
> - }
> + if (!np->dev)
> + return;
> +
> + npinfo = np->dev->npinfo;
> + if (npinfo) {
> + if (npinfo->rx_np == np) {
> + spin_lock_irqsave(&npinfo->rx_lock, flags);
> + npinfo->rx_np = NULL;
> + npinfo->rx_flags &= ~NETPOLL_RX_ENABLED;
> + spin_unlock_irqrestore(&npinfo->rx_lock, flags);
> + }
>
> - np->dev->npinfo = NULL;
> - if (atomic_dec_and_test(&npinfo->refcnt)) {
> - skb_queue_purge(&npinfo->arp_tx);
> - skb_queue_purge(&npinfo->txq);
> + np->dev->npinfo = NULL;
> + if (atomic_dec_and_test(&npinfo->refcnt)) {
> + skb_queue_purge(&npinfo->arp_tx);
> + skb_queue_purge(&npinfo->txq);
> + if (delayed_work_pending(&npinfo->tx_work)) {
> cancel_rearming_delayed_work(&npinfo->tx_work);
> flush_scheduled_work();
> -
> - kfree(npinfo);
> }
> - }
>
> - dev_put(np->dev);
> + kfree(npinfo);
> + }
> }
>
> + dev_put(np->dev);
> np->dev = NULL;
> }
>
> --
> 1.5.0.6
>
Folkert van Heusden
--
Multitail - gibkaja utilita po sledovaniju log-fajlov i vyvoda
kommand. Fil'trovanie, raskrašivanie, slijanie, vizual'noe sravnenie,
i t.d. http://www.vanheusden.com/multitail/
----------------------------------------------------------------------
Phone: +31-6-41278122, PGP-key: 1F28D8AE, www.vanheusden.com
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
