From: Mel Gorman <mgorman@suse.de>
To: Kautuk Consul <consul.kautuk@gmail.com>
Cc: Russell King <rmk@arm.linux.org.uk>,
linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org
Subject: Re: [PATCH] ARM: sparsemem: Enable CONFIG_HOLES_IN_ZONE config option for SparseMem and HAS_HOLES_MEMORYMODEL for linux-3.0.
Date: Wed, 3 Aug 2011 14:28:39 +0100 [thread overview]
Message-ID: <20110803132839.GG19099@suse.de> (raw)
In-Reply-To: <CAFPAmTR79S3AVXrAFL5bMkhs2droL8THUCCPY23Ar5x_oftheQ@mail.gmail.com>
On Wed, Aug 03, 2011 at 05:59:03PM +0530, Kautuk Consul wrote:
> Hi Mel,
>
> Sorry for the formatting.
>
> I forgot to include the following entire backtrace:
> #> cp test_huge_file nfsmnt
> kernel BUG at mm/page_alloc.c:849!
> Unable to handle kernel NULL pointer dereference at virtual address 00000000
> pgd = ce9f0000
> <SNIP>
> Backtrace:
> [<c00269ac>] (__bug+0x0/0x30) from [<c008e8b0>]
> (move_freepages_block+0xd4/0x158)
It's still horribly mangled and pretty much unreadable but at least we
know where the bug is hitting.
> <SNIP>
>
> Since I was testing on linux-2.6.35.9, line 849 in page_alloc.c is the
> same line as you have mentioned:
> BUG_ON(page_zone(start_page) != page_zone(end_page))
>
> I reproduce this crash by altering the memory banks' memory ranges
> such that they are not aligned to the SECTION_SIZE_BITS size.
How are you altering the ranges? Are you somehow breaking
the checks based on the information in stuct zone that is in
move_freepages_block()?
It no longer seems like a punching-hole-in-memmap problem. Can
you investigate how and why the range of pages passed in to
move_freepages() belong to different zones?
Thanks.
--
Mel Gorman
SUSE Labs
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2011-08-03 13:28 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-08-02 12:08 [PATCH] ARM: sparsemem: Enable CONFIG_HOLES_IN_ZONE config option for SparseMem and HAS_HOLES_MEMORYMODEL for linux-3.0 Kautuk Consul
2011-08-03 11:05 ` Mel Gorman
2011-08-03 12:29 ` Kautuk Consul
2011-08-03 13:28 ` Mel Gorman [this message]
2011-08-04 9:36 ` Kautuk Consul
2011-08-04 10:09 ` Mel Gorman
2011-08-05 5:57 ` Kautuk Consul
2011-08-05 8:47 ` Mel Gorman
2011-08-05 11:40 ` Kautuk Consul
2011-08-24 12:31 ` Kautuk Consul
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20110803132839.GG19099@suse.de \
--to=mgorman@suse.de \
--cc=consul.kautuk@gmail.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-mm@kvack.org \
--cc=rmk@arm.linux.org.uk \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).