Re: 3.2rc7 rcu_preempt stalls and tasks blocked.

[Mantas]

On 2011-12-24 16:09, Jonathan Hudson wrote:
> Ever since 3.1, I've been experiencing rcu_preempt stalls, tasks
> blocked and subsequent lock ups on an eeepc 901. Judging by the thread
> <https://bugs.archlinux.org/task/26847> on the Arch forums, this is not
> an uncommon experience. 

Can confirm on ASUS K52JT, using 3.2 (Arch Linux) and various git builds
starting around 3.2-rc6/7. Appears to be caused by heavier wireless
network activity (ath9k, Atheros AR9285, open network, IPv4 & IPv6),
such as BitTorrent -- although not by ordinary HTTP or such. Other posts
in the Arch bug report say having ipv6 loaded/enabled is causing the
problem.

During the lockup, accessing certain files in /proc (can't remember all,
but /proc/*/mounts and /proc/*/cgroup included) causes the process to
hang; same when running `ip`, `iwconfig` and related tools. Often (but
not always), killing NetworkManager makes everything work again.

Hoping for a fix someday.

-- 
Mantas M.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/