netdev - [PATCH net 2/2] net: dsa: hellcreek: Adjust schedule look ahead window

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]

Date:   Wed, 25 Aug 2021 15:58:13 +0200
From:   Kurt Kanzenbach <kurt@...utronix.de>
To:     "David S. Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>
Cc:     Andrew Lunn <andrew@...n.ch>,
        Vivien Didelot <vivien.didelot@...il.com>,
        Florian Fainelli <f.fainelli@...il.com>,
        Vladimir Oltean <olteanv@...il.com>, netdev@...r.kernel.org,
        Sebastian Andrzej Siewior <bigeasy@...utronix.de>,
        Kurt Kanzenbach <kurt@...utronix.de>
Subject: [PATCH net 2/2] net: dsa: hellcreek: Adjust schedule look ahead window

Traffic schedules can only be started up to eight seconds within the
future. Therefore, the driver periodically checks every two seconds whether the
admin base time provided by the user is inside that window. If so the schedule
is started. Otherwise the check is deferred.

However, according to the programming manual the look ahead window size should
be four - not eight - seconds. By using the proposed value of four seconds
starting a schedule at a specified admin base time actually works as expected.

Fixes: 24dfc6eb39b2 ("net: dsa: hellcreek: Add TAPRIO offloading support")
Signed-off-by: Kurt Kanzenbach <kurt@...utronix.de>
---
 drivers/net/dsa/hirschmann/hellcreek.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/dsa/hirschmann/hellcreek.c b/drivers/net/dsa/hirschmann/hellcreek.c
index b57aea92684b..7062db6a083c 100644
--- a/drivers/net/dsa/hirschmann/hellcreek.c
+++ b/drivers/net/dsa/hirschmann/hellcreek.c
@@ -1550,7 +1550,7 @@ static bool hellcreek_schedule_startable(struct hellcreek *hellcreek, int port)
 	/* Calculate difference to admin base time */
 	base_time_ns = ktime_to_ns(hellcreek_port->current_schedule->base_time);
 
-	return base_time_ns - current_ns < (s64)8 * NSEC_PER_SEC;
+	return base_time_ns - current_ns < (s64)4 * NSEC_PER_SEC;
 }
 
 static void hellcreek_start_schedule(struct hellcreek *hellcreek, int port)
-- 
2.30.2