linux-kernel - Re: Device hang when offlining a CPU due to IRQ misrouting

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]

Message-Id: <JIZ905$469B6EF277FE655A66C9ACE2321FC036@laposte.net>
Date:	Fri,  1 Jun 2007 23:57:41 +0200
From:	Emmanuel Fusté <emmanuel.fuste@...oste.net>
To:	"djwong" <djwong@...ibm.com>, "ebiederm" <ebiederm@...ssion.com>
Cc:	"linux-kernel" <linux-kernel@...r.kernel.org>
Subject: Re: Device hang when offlining a CPU due to IRQ misrouting

> There exists a similar scenario.  Set the IRQ affinity to a
bunch of
> CPUs, watch /proc/interrupts to see which CPU is actually
servicing the
> interrupts, then offline that CPU.  The kernel does not
reroute the IRQ
> to any of the other CPUs and the device also hangs.
>
> The furthest that I've dug is that it works on 2.6.17 and is
broken in
> 2.6.22-rc3 and 2.6.21.  Will git-bisect further, but I
wanted to know if
> anyone else has seen this sort of problem.  afaik, this
seems to happen
> with both IOAPIC and MSI interrupts, possibly more.
Hi,
As a side note, on my very old SMP machine, 2.6.20 correctly
load-balance IRQs across CPU but 2.6.21 not. I know that
in-kernel IRQ load balancer is marked as deprecated and
somewhat broken, but with your report it make me think it
could be a bug in the IRQ rerouting part in my case too and
not necessary in the load-balancer (decision) part.

Emmanuel.

---

Créez votre adresse électronique prenom.nom@...oste.net 
1 Go d'espace de stockage, anti-spam et anti-virus intégrés.

-
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/