linux-kernel - RE: [EXT] Re: [RFC PATCH] arm64: defconfig: Disable fine-grained task level IRQ time accounting

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]

Message-ID: <VI1PR04MB406286E9BF44AAE1339D2174F4700@VI1PR04MB4062.eurprd04.prod.outlook.com>
Date:   Wed, 29 Jul 2020 08:50:34 +0000
From:   Alison Wang <alison.wang@....com>
To:     Kurt Kanzenbach <kurt.kanzenbach@...utronix.de>,
        "catalin.marinas@....com" <catalin.marinas@....com>,
        "will@...nel.org" <will@...nel.org>,
        "paulmck@...nel.org" <paulmck@...nel.org>,
        "mw@...ihalf.com" <mw@...ihalf.com>, Leo Li <leoyang.li@....com>,
        Vladimir Oltean <vladimir.oltean@....com>,
        "linux-arm-kernel@...ts.infradead.org" 
        <linux-arm-kernel@...ts.infradead.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
CC:     Thomas Gleixner <tglx@...utronix.de>,
        Anna-Maria Gleixner <anna-maria@...utronix.de>
Subject: RE: [EXT] Re: [RFC PATCH] arm64: defconfig: Disable fine-grained task
 level IRQ time accounting

Hi, Kurt,

> On Wed Jul 29 2020, Alison Wang wrote:
> > In the current arm64 defconfig, CONFIG_IRQ_TIME_ACCOUNTING is enabled
> > as default. According to my tests on NXP's LayerScape and i.MX
> > platforms, the system hangs when running the command "stress-ng
> > --hrtimers 1" with CONFIG_IRQ_TIME_ACCOUNTING enabled. Disabling this
> > option, the issue disappears. CONFIG_IRQ_TIME_ACCOUNTING causes
> > serious performance impact when running hrtimer stress test at the same
> time.
> 
> I think instead of disabling the option for all arm64 devices, it might be better
> to analyze the root-cause why the hrtimer test hangs when this option is
> enabled.
> 
> +Cc hrtimer maintainers: Thomas and Anna-Maria
> 
[Alison] Yes, I agree. I hope others can give me some clues for the root cause.


Best Regards,
Alison Wang