linux-kernel - Re: [PATCH 02/16] user_ns: use new hashtable implementation

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: <50300E9A.1060501@gmail.com>
Date:	Sat, 18 Aug 2012 23:52:26 +0200
From:	Sasha Levin <levinsasha928@...il.com>
To:	"Eric W. Biederman" <ebiederm@...ssion.com>
CC:	Linus Torvalds <torvalds@...ux-foundation.org>,
	Tejun Heo <tj@...nel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 02/16] user_ns: use new hashtable implementation

On 08/15/2012 01:52 AM, Eric W. Biederman wrote:
> Sasha Levin <levinsasha928@...il.com> writes:
>> > Switch user_ns to use the new hashtable implementation. This reduces the amount of
>> > generic unrelated code in user_ns.
> Two concerns here.
> 1) When adding a new entry you recompute the hash where previously that
>    was not done.  I believe that will slow down adding of new entries.

Since the hashtable doesn't expose the internal hashing to the user of the
hashtable it would require adding a new interface to deal with in.

I don't feel that a whole new interface to optimize out something which is very
cheap (one multiplication + shift) in this case, I'd rather avoid having a new
interface.

Is it ok with you if I leave it as is in the next version of the patch?
--
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/