2.5.25: buffer layer error at buffer.c:406

2.5.25: buffer layer error at buffer.c:406

[Peter Osterlund]

When I booted 2.5.25 I got the error "buffer layer error at
buffer.c:406". It happened three times within one second. After that it
didn't happen again. The error messages didn't seem to cause any harm.

I rebooted the machine, but the error didn't show up again. The only
difference was that on the first boot, the machine decided to run an
ext2 file system check.

All three back traces were identical:

c2391e08 00000196 00000000 c02dc6c0 c3f430c0 c013a0d0 c3f430c0 0029a000 
       00000000 00000000 00000000 00000800 0029a000 00000400 c013a4b5 c3f430c0 
       0029a000 00000000 00000800 00000005 00000400 c013aa37 00000000 c013aa67 
Call Trace: [<c013a0d0>] [<c013a4b5>] [<c013aa37>] [<c013aa67>] [<c012703a>] 
   [<c013b370>] [<c01618d0>] [<c01294af>] [<c01618d0>] [<c0123500>] [<c0137dbc>]
   [<c0125f85>] [<c0137eba>] [<c0106f17>] 
Warning (Oops_read): Code line not seen, dumping what data is available

Trace; c013a0d0 <__find_get_block+c0/e0>
Trace; c013a4b5 <unmap_underlying_metadata+15/50>
Trace; c013aa37 <__block_prepare_write+187/3e0>
Trace; c013aa67 <__block_prepare_write+1b7/3e0>
Trace; c012703a <__add_to_page_cache+1a/d0>
Trace; c013b370 <block_prepare_write+20/40>
Trace; c01618d0 <ext2_get_block+0/420>
Trace; c01294af <generic_file_write+5ff/7b0>
Trace; c01618d0 <ext2_get_block+0/420>
Trace; c0123500 <unmap_page_range+40/60>
Trace; c0137dbc <vfs_write+9c/130>
Trace; c0125f85 <do_munmap+115/120>
Trace; c0137eba <sys_write+2a/40>
Trace; c0106f17 <syscall_call+7/b>

-- 
Peter Osterlund - petero2@telia.com
http://w1.894.telia.com/~u89404340

Re: 2.5.25: buffer layer error at buffer.c:406

[Andrew Morton]

Peter Osterlund wrote:
> 
> When I booted 2.5.25 I got the error "buffer layer error at
> buffer.c:406". It happened three times within one second. After that it
> didn't happen again. The error messages didn't seem to cause any harm.
> 
> I rebooted the machine, but the error didn't show up again. The only
> difference was that on the first boot, the machine decided to run an
> ext2 file system check.
> 

Looks like the fsck left some pagecache behind, perhaps with a
different blocksize.  I have some adjustments in that ares which
_may_ make it go away - not sure.

Is it the root filesystem?  And could you please send me the
`dumpe2fs -h' output for that filesystem?

Thanks.

-

Re: 2.5.25: buffer layer error at buffer.c:406

[Peter Osterlund]

Andrew Morton <akpm@zip.com.au> writes:

> Peter Osterlund wrote:
> > 
> > When I booted 2.5.25 I got the error "buffer layer error at
> > buffer.c:406". It happened three times within one second. After that it
> > didn't happen again. The error messages didn't seem to cause any harm.
> > 
> > I rebooted the machine, but the error didn't show up again. The only
> > difference was that on the first boot, the machine decided to run an
> > ext2 file system check.
> > 
> 
> Looks like the fsck left some pagecache behind, perhaps with a
> different blocksize.  I have some adjustments in that ares which
> _may_ make it go away - not sure.
> 
> Is it the root filesystem?  And could you please send me the
> `dumpe2fs -h' output for that filesystem?

Yes, it is the root filesystem, which is the only filesystem on that
machine (An old laptop). I noticed the block size is 1Kb, maybe that
has something to do with the problem.

pengo:/home/petero# /sbin/dumpe2fs -h /dev/hda4
dumpe2fs 1.25 (20-Sep-2001)
Filesystem volume name:   <none>
Last mounted on:          <not available>
Filesystem UUID:          e02ff420-1808-11d2-92dd-b0a589171a72
Filesystem magic number:  0xEF53
Filesystem revision #:    0 (original)
Filesystem features:      (none)
Filesystem state:         not clean
Errors behavior:          Continue
Filesystem OS type:       Linux
Inode count:              759808
Block count:              3032064
Reserved block count:     5000
Free blocks:              202811
Free inodes:              625901
First block:              1
Block size:               1024
Fragment size:            1024
Blocks per group:         8192
Fragments per group:      8192
Inodes per group:         2048
Inode blocks per group:   256
Last mount time:          Thu Jul 11 21:16:09 2002
Last write time:          Fri Jul 12 00:23:44 2002
Mount count:              2
Maximum mount count:      20
Last checked:             Thu Jul 11 20:36:03 2002
Check interval:           15552000 (6 months)
Next check after:         Tue Jan  7 19:36:03 2003
Reserved blocks uid:      0 (user root)
Reserved blocks gid:      0 (group root)

-- 
Peter Osterlund - petero2@telia.com
http://w1.894.telia.com/~u89404340