linux-kernel - Re: [PATCH v2 3/3] vsprintf: dump full information of page flags in pGp

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: <20210201141505.GR308988@casper.infradead.org>
Date:   Mon, 1 Feb 2021 14:15:05 +0000
From:   Matthew Wilcox <willy@...radead.org>
To:     Yafang Shao <laoar.shao@...il.com>
Cc:     andriy.shevchenko@...ux.intel.com, david@...hat.com,
        vbabka@...e.cz, linmiaohe@...wei.com, cl@...ux.com,
        penberg@...nel.org, rientjes@...gle.com, iamjoonsoo.kim@....com,
        akpm@...ux-foundation.org, pmladek@...e.com, rostedt@...dmis.org,
        sergey.senozhatsky@...il.com, linux@...musvillemoes.dk,
        linux-mm@...ck.org, linux-kernel@...r.kernel.org,
        Joe Perches <joe@...ches.com>
Subject: Re: [PATCH v2 3/3] vsprintf: dump full information of page flags in
 pGp

On Mon, Feb 01, 2021 at 07:56:10PM +0800, Yafang Shao wrote:
> - Before the patch,
> [ 6343.396602] Slab 0x000000004382e02b objects=33 used=3 fp=0x000000009ae06ffc flags=0x17ffffc0010200(slab|head)
> 
> - After the patch,
> [ 6871.296131] Slab 0x00000000c0e19a37 objects=33 used=3 fp=0x00000000c4902159 flags=0x17ffffc0010200(Node 0,Zone 2,Lastcpupid 0x1fffff,slab|head)

I would suggest it will be easier to parse as:

flags=0x17ffffc0010200(slab|head|node=0|zone=2|lastcpupid=0x1fffff)

That should alleviate the concerns about debugfs format change -- we've
never guaranteed that flag names won't change, and they now look enough
like flags that parsers shouldn't fall over them.