netdev - RE: Realtek 8139 driver (8139too.c) TX Timeout doesn't allow interrupt handler to disable receive interrupts at high bi-directional traffic

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-next>] [day] [month] [year] [list]

Date:	Wed, 29 Nov 2006 14:20:31 +0530
From:	"Basheer, Mansoor Ahamed" <mansoor.ahamed@...com>
To:	"Francois Romieu" <romieu@...zoreil.com>
Cc:	<netdev@...r.kernel.org>
Subject: RE: Realtek 8139 driver (8139too.c) TX Timeout doesn't allow interrupt handler to disable receive interrupts at high bi-directional traffic

Francois Romieu [mailto:romieu@...zoreil.com] wrote:

> Afaics your change may disable the Rx irq right after the poll routine

> enabled it again. It will not always work either.
> 
> The (slow) timeout watchdog could grab the poll handler and hack the 
> irq mask depending on whether poll was scheduled or not.

Could you please confirm whether the attached patch would work?
I tested it and it works for me.


Signed-off-by: Mansoor Ahamed <mansoor.ahamed@...com>

--- old/8139too.c	2006-11-14 10:44:27.000000000 +0530
+++ new/8139too.c	2006-11-14 10:44:18.000000000 +0530
@@ -1438,8 +1438,18 @@
 	if ((!(tmp & CmdRxEnb)) || (!(tmp & CmdTxEnb)))
 		RTL_W8 (ChipCmd, CmdRxEnb | CmdTxEnb);
 
-	/* Enable all known interrupts by setting the interrupt mask. */
-	RTL_W16 (IntrMask, rtl8139_intr_mask);
+	local_irq_disable();
+	/* Don't enable RX if RX was already scheduled */
+	if(test_bit(__LINK_STATE_START, &dev->state) &&
+			test_bit(__LINK_STATE_RX_SCHED, &dev->state) ) {
+		/* Enable all interrupts except RX by setting the
interrupt mask. */
+		RTL_W16 (IntrMask, rtl8139_norx_intr_mask);
+	}
+	else {
+		/* Enable all known interrupts by setting the interrupt
mask. */ 
+		RTL_W16 (IntrMask, rtl8139_intr_mask);
+	}
+	local_irq_enable();
 }

Thanks
Mansoor
-
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