linux-kernel - 答复: 32bit resctrl? (was Re: [PATCH v2] fs/resctrl: fix domid loss precision issue)

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:
 <KL1PR0601MB57739915A074146DF05632A4E6282@KL1PR0601MB5773.apcprd06.prod.outlook.com>
Date: Fri, 15 Mar 2024 00:56:41 +0000
From: Rex Nie <rex.nie@...uarmicro.com>
To: Peter Newman <peternewman@...gle.com>
CC: "james.morse@....com" <james.morse@....com>, "x86@...nel.org"
	<x86@...nel.org>, "Luck, Tony" <tony.luck@...el.com>, Babu Moger
	<babu.moger@....com>, Borislav Petkov <bp@...en8.de>, "fenghua.yu@...el.com"
	<fenghua.yu@...el.com>, "ilpo.jarvinen@...ux.intel.com"
	<ilpo.jarvinen@...ux.intel.com>, "linux-kernel@...r.kernel.org"
	<linux-kernel@...r.kernel.org>, Reinette Chatre <reinette.chatre@...el.com>
Subject:
 答复: 32bit resctrl? (was Re: [PATCH v2] fs/resctrl: fix domid loss precision issue)

HI Peter,
	In next link, Maciej Wieczor-Retman and I talked about arm cache id. FYI
	https://lore.kernel.org/all/KL1PR0601MB57730994C0501212DF6DDC6EE6242@KL1PR0601MB5773.apcprd06.prod.outlook.com/
BRs
Rex

> -----邮件原件-----
> 发件人: Peter Newman <peternewman@...gle.com>
> 发送时间: 2024年3月15日 8:05
> 收件人: Rex Nie <rex.nie@...uarmicro.com>
> 抄送: james.morse@....com; x86@...nel.org; Luck, Tony
> <tony.luck@...el.com>; Babu Moger <babu.moger@....com>; Borislav
> Petkov <bp@...en8.de>; fenghua.yu@...el.com; ilpo.jarvinen@...ux.intel.com;
> linux-kernel@...r.kernel.org; Reinette Chatre <reinette.chatre@...el.com>
> 主题: Re: 32bit resctrl? (was Re: [PATCH v2] fs/resctrl: fix domid loss precision
> issue)
> 
> External Mail: This email originated from OUTSIDE of the organization!
> Do not click links, open attachments or provide ANY information unless you
> recognize the sender and know the content is safe.
> 
> 
> Hi Rex,
> 
> On Thu, Mar 14, 2024 at 8:25 AM Reinette Chatre <reinette.chatre@...el.com>
> wrote:
> >
> > +x86 maintainers, Tony, Babu, Peter
> >
> > Hi Everybody,
> >
> > On 3/12/2024 12:53 AM, Rex Nie wrote:
> > > Below statement from mkdir_mondata_subdir function will loss
> > > precision, because it assigns int to 14 bits bitfield.
> > >       priv.u.domid = d->id;
> > >
> > > On some platforms(e.g.,x86), the max cache_id is the amount of L3
> > > caches, so it is not in the range of 0x3fff. But some platforms use
> > > higher cache_id, e.g., arm uses cache_id as locator for cache MSC.
> > > This will cause below issue if cache_id > 0x3fff likes:
> > > /sys/fs/resctrl/mon_groups/p1/mon_data/mon_L3_1048564 # cat
> > > llc_occupancy
> 
> This domain ID seems unreadable in decimal and I'm wondering whether it's
> the best value to use to identify the domain. Does this system have over 1
> million L3 domains?
> 
> Thanks!
> -Peter