linux-kernel - Re: Mark IPW2100 as BROKEN: Fatal interrupt. Scheduling firmware restart.

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: <20080921202057.GB25052@2ka.mipt.ru>
Date:	Mon, 22 Sep 2008 00:20:57 +0400
From:	Evgeniy Polyakov <johnpol@....mipt.ru>
To:	Arjan van de Ven <arjan@...radead.org>
Cc:	Johannes Berg <johannes@...solutions.net>, netdev@...r.kernel.org,
	linux-kernel@...r.kernel.org, ipw2100-devel@...ts.sourceforge.net,
	linux-wireless@...r.kernel.org, yi.zhu@...el.com,
	reinette.chatre@...el.com, jgarzik@...ox.com,
	linville@...driver.com, davem@...emloft.net
Subject: Re: Mark IPW2100 as BROKEN: Fatal interrupt. Scheduling firmware restart.

On Sun, Sep 21, 2008 at 12:43:32PM -0700, Arjan van de Ven (arjan@...radead.org) wrote:
> > @@ -3174,6 +3176,10 @@ static void ipw2100_irq_tasklet(struct
> > ipw2100_priv *priv) if (inta & IPW2100_INTA_FATAL_ERROR) {
> >  		printk(KERN_WARNING DRV_NAME
> >  		       ": Fatal interrupt. Scheduling firmware
> > restart.\n");
> > +		WARN_ON(1);
> > +
> > +		BUG_ON(ipw2100_max_fatal_ints-- <= 0);
> 
> BUG_ON in interrupt context is just extremely hostile, since it means
> the box is dead.
>
> also I would suggest using WARN_ON_ONCE() 

Well, I actually wanted to have a bug there because of it, but now I
think that annoying repeated warning is enough to bring attention to the
problem by putting bug information into some magic special place called
kerneloops collection.

Consider for inclusing for the upcoming kernel to get wider
notifications. Yes, it is not a bugfix, I know.

diff --git a/drivers/net/wireless/ipw2100.c b/drivers/net/wireless/ipw2100.c
index 19a401c..6599211 100644
--- a/drivers/net/wireless/ipw2100.c
+++ b/drivers/net/wireless/ipw2100.c
@@ -206,6 +206,9 @@ MODULE_PARM_DESC(disable, "manually disable the radio (default 0 [radio on])");
 
 static u32 ipw2100_debug_level = IPW_DL_NONE;
 
+static int ipw2100_max_fatal_ints = 10;
+module_param(ipw2100_max_fatal_ints, int, 0644);
+
 #ifdef CONFIG_IPW2100_DEBUG
 #define IPW_DEBUG(level, message...) \
 do { \
@@ -3174,6 +3177,9 @@ static void ipw2100_irq_tasklet(struct ipw2100_priv *priv)
 	if (inta & IPW2100_INTA_FATAL_ERROR) {
 		printk(KERN_WARNING DRV_NAME
 		       ": Fatal interrupt. Scheduling firmware restart.\n");
+
+		WARN_ON(ipw2100_max_fatal_ints-- >= 0);
+
 		priv->inta_other++;
 		write_register(dev, IPW_REG_INTA, IPW2100_INTA_FATAL_ERROR);
 


-- 
	Evgeniy Polyakov
--
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/