Subject: Re: next-20080723: build fails for dm-snapshot.ko

From: Adrian Bunk <[email-masked]>
Date: Wed, 23 Jul 2008 23:51:02 +0300

On Wed, Jul 23, 2008 at 07:58:37PM +0200, Thomas Meyer wrote:
> 
>   Building modules, stage 2.
> Kernel: arch/x86/boot/bzImage is ready  (#24)
>   MODPOST 1518 modules
> ERROR: "__umoddi3" [drivers/md/dm-snapshot.ko] undefined!
> WARNING: modpost: Found 6 section mismatch(es).
> To see full details build your kernel with:
> 'make CONFIG_DEBUG_SECTION_MISMATCH=y'
> make[1]: *** [__modpost] Error 1
> make: *** [modules] Error 2
> 
> 
> CONFIG_MD=y
> CONFIG_BLK_DEV_MD=y
> CONFIG_MD_LINEAR=m
> CONFIG_MD_RAID0=m
> CONFIG_MD_RAID1=m
> CONFIG_MD_RAID10=m
> CONFIG_MD_RAID456=m
> CONFIG_MD_RAID5_RESHAPE=y
> CONFIG_MD_MULTIPATH=m
> CONFIG_MD_FAULTY=m
> CONFIG_BLK_DEV_DM=m
> CONFIG_DM_DEBUG=y
> CONFIG_DM_CRYPT=m
> CONFIG_DM_SNAPSHOT=m
> CONFIG_DM_MIRROR=m
> CONFIG_DM_ZERO=m
> CONFIG_DM_MULTIPATH=m
> # CONFIG_DM_DELAY is not set
> CONFIG_DM_UEVENT=y

and CONFIG_LBD=y

In the following code in drivers/md/dm-exception-store.c:persistent_prepare():

                            vvv
        if ((++ps->next_free % stride) == 1)
                ps->next_free++;

Caused by:

commit 7624decba23d3e7a8e7411214501cfaf19041c30
Author: Mikulas Patocka <[email-masked]>
Date:   Wed Jul 23 10:05:33 2008 +1000

    dm-exception-store-64-bit-values
    
    Change uint32_t into chunk_t to remove 32-bit limitation on the
    number of chunks on systems with 64-bit sector numbers.
    
    Signed-off-by: Mikulas Patocka <[email-masked]>
    Signed-off-by: Alasdair G Kergon <[email-masked]>

cu
Adrian

-- 

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       "Only a promise," Lao Er said.
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