linux-kernel - Re: Change PAGE_SIZE from minimum 4k to 12k

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 for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 16 May 2017 12:46:26 -0400
From:   lsorense@...lub.uwaterloo.ca (Lennart Sorensen)
To:     Kevin McKinney <klmckinney1@...il.com>
Cc:     linux-kernel@...r.kernel.org
Subject: Re: Change PAGE_SIZE from minimum 4k to 12k

On Tue, May 16, 2017 at 11:27:08AM -0400, Kevin McKinney wrote:
> Hi Everyone,
> 
> Would it be possible to have a custom block device driver read/write
> in increments of 12k instead of reading/writing data in 4k increments?
> In other words, I would like to change the default page size on a
> x86_64 platform (4.4.0 kernel) from 4k to 12k as the minimum page
> size?  I understand I may have negative performance due to
> fragmentation. Any help would be appreciated.
> 
> If this is the wrong mailing list, please let me know the right one to use.

I believe the answer is no.

x86 supports page sizes of 4K, 2M and 1G.  I don't believe anything else
is possible with the hardware.

The page size is not a software invention.

-- 
Len Sorensen