Re: Bad page state in process 'nfsd' with xfs

[Nathan Scott <nathans@sgi.com>]

Hi there,

On Fri, Apr 28, 2006 at 09:22:23PM +0100, David Greaves wrote:
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> This was with 2.6.16.9
> 
> There's an nfs export from an xfs on an lvm on a raid5 on some
> libata/sata disks.
> (cc'ing xfs since I recall rumoured(?) badness in old nfs/xfs/md/lvm
> setups and xfs_sendfile is mentioned)

Really old (early 2.6) or previously with 4Kstacks this used to be
a problem, but should not be with your kernel version.

> Bad page state in process 'nfsd'
> page:b1602060 flags:0x80000008 mapping:00000000 mapcount:0 count:16777216
> Trying to fix it up, but a reboot is needed
> Backtrace:
>  [<b013bda2>] bad_page+0x62/0x90
>  [<b013c1c8>] prep_new_page+0x78/0x80
>  [<b013c6b6>] buffered_rmqueue+0xf6/0x1f0
>  [<b013c8e2>] get_page_from_freelist+0x92/0xb0

Hmm... so, your page flags field there (0x80000008) has the 33rd and
4th bits set - 4 is pageuptodate, which is fine, but 33 seems odd
(perhaps some arch-specific bit?  or a single bit error...).

But, the warning is triggered by the page count (16777216 above), and
that is 0x1000000 -- which is a huge, improbable count; that looks to
me like it could very well be the result of a single bit error too.

You may have a hardware problem - try running memtest I guess.

cheers.

-- 
Nathan