linux-kernel - Re: [PATCH 2 of 4] hotplug-memory: adding non-section-aligned memory is bad

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]

Date:	Fri, 28 Mar 2008 10:27:19 +0900
From:	KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>
To:	Jeremy Fitzhardinge <jeremy@...p.org>
Cc:	Ingo Molnar <mingo@...e.hu>, LKML <linux-kernel@...r.kernel.org>,
	Rusty Russell <rusty@...tcorp.com.au>,
	Yasunori Goto <y-goto@...fujitsu.com>,
	Christoph Lameter <clameter@....com>,
	Dave Hansen <dave@...ux.vnet.ibm.com>,
	Andrew Morton <akpm@...ux-foundation.org>
Subject: Re: [PATCH 2 of 4] hotplug-memory: adding non-section-aligned
 memory is bad

On Thu, 27 Mar 2008 17:28:38 -0700
Jeremy Fitzhardinge <jeremy@...p.org> wrote:
> diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
> --- a/include/linux/mmzone.h
> +++ b/include/linux/mmzone.h
> @@ -784,6 +784,9 @@
>  #define PAGES_PER_SECTION       (1UL << PFN_SECTION_SHIFT)
>  #define PAGE_SECTION_MASK	(~(PAGES_PER_SECTION-1))
>  
> +#define SECTION_SIZE		(1UL << SECTION_SIZE_BITS)
> +#define SECTION_SIZE_MASK	(SECTION_SIZE - 1)
> +
>  #define SECTION_BLOCKFLAGS_BITS \
>  	((1UL << (PFN_SECTION_SHIFT - pageblock_order)) * NR_PAGEBLOCK_BITS)
>  
> diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
> --- a/mm/memory_hotplug.c
> +++ b/mm/memory_hotplug.c
> @@ -300,6 +300,11 @@
>  	int ret;
>  	u64 start = res->start;
>  	u64 size = res->end - res->start + 1;
> +
> +	/* Adding non-section-aligned memory will give unexpected
> +	   and unintuitive results. */
> +	WARN_ON((start & SECTION_SIZE_MASK) != 0);
> +	WARN_ON((size & SECTION_SIZE_MASK) != 0);
>  
Why just WARNING ? not BUG_ON?

Thanks,
-Kame

--
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/