linux-kernel - Re: Interrupts are being dropped under heavy IO on -rt .

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, 15 Apr 2009 12:48:02 -0700
From:	Andrew Vasquez <andrew.vasquez@...gic.com>
To:	jvrao <jvrao@...ux.vnet.ibm.com>
Cc:	LKML <linux-kernel@...r.kernel.org>,
	rt-users <linux-rt-users@...r.kernel.org>,
	Mike Anderson <andmike@...ux.vnet.ibm.com>,
	"Luis Claudio R. Goncalves" <lgoncalv@...hat.com>,
	Linux Driver <Linux-Driver@...gic.com>
Subject: Re: Interrupts are being dropped under heavy IO on -rt .

On Fri, 10 Apr 2009, jvrao wrote:

> Qlogic driver uses MSI-EDGE interrupts by default.
>  
> On -rt kernel under heavy IO load we observed that the driver missed 
> interrupts occasionally.
> 
> Missing interrupts caused spurious mailbox timeouts and path failovers.
> 
> Suspecting MSI interrupts, we disabled MSI and forcing the driver to use 
> APIC interrupts (Patch attached).
> 
> With this change, our IO tests ran for extended period of time without 
> any issues.
> 
> It would be interesting to see if the MSI infrastructure itself has 
> issues on realtime, or it is the combination of qla2xxx/MSI.
> 
> Right now we don't have any setup to test out MSI with other adapters. 
> Hence, wondering if anyone faced similar issues.

Could you perhaps provide some details on hardware used within your
testing -- HBA type, storage, etc?  Also, can you share any logs of
the failures with extended-error-logging enabled
(ql2xextended_error_logging)?

Regards,
Andrew Vasquez
--
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/