linux-kernel - Re: [PATCH] [RFC] mm: slab: separate slab

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] [day] [month] [year] [list]

Date:	Thu, 12 Dec 2013 11:28:29 -0800
From:	Dave Hansen <dave@...1.net>
To:	Christoph Lameter <cl@...ux.com>
CC:	linux-kernel@...r.kernel.org, linux-mm@...ck.org,
	kirill.shutemov@...ux.intel.com, Andi Kleen <ak@...ux.intel.com>
Subject: Re: [PATCH] [RFC] mm: slab: separate slab_page from 'struct page'

On 12/12/2013 09:37 AM, Christoph Lameter wrote:
> On Tue, 10 Dec 2013, Dave Hansen wrote:
>> See? *EVERYTHING* is overridden by at least one of the sl?b allocators
>> except ->flags.  In other words, there *ARE* no relationships when it
>> comes to the sl?bs, except for page->flags.
> 
> Slab objects can be used for I/O and then the page fields become
> important.

OK, which fields?  How are they important?  Looking at 'struct page', I
don't see any fields other than ->flags that the slab allocators leave
alone.

I do see some refcounting (page->_count) done on
request_queue->dma_drain_buffer which is kmalloc()'d.  Although, I'm a
bit skeptical that this is correct or has been audited because the slabs
do seem to write over this storage.  Anything needing to do per-page
could probably be converted over to a raw alloc_pages() anyway because
it couldn't possibly be doing sub-page-size allocations.

What other cases were you thinking of?
--
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/