[Pvfs2-developers] pvfs2-1.4.0 kernel module doesn't load on 2.6.8: mmput/mmgrab undefined

[Murali Vilayannur]

Hi Alexander,

> and in /var/log/kern.log:
> Mar 23 10:51:36 fredo kernel: pvfs2: Unknown symbol mmput
> Mar 23 10:51:36 fredo kernel: pvfs2: Unknown symbol mmgrab
>
> I recompiled the kernel after adding the following two lines:
>
> diff -ur kernel-source-2.6.8/kernel/fork.c
> kernel-source-2.6.8-patched/kernel/fork.c
> --- kernel-source-2.6.8/kernel/fork.c   2004-08-14 07:36:16.000000000 +0200
> +++ kernel-source-2.6.8-patched/kernel/fork.c   2006-03-22
> 20:31:54.000000000 +0
> 100
> @@ -466,6 +466,8 @@
>          }
>   }
>
> +EXPORT_SYMBOL_GPL(mmput);
> +
>   /*
>    * Checks if the use count of an mm is non-zero and if so
>    * returns a reference to it after bumping up the use count.
> @@ -483,6 +485,8 @@
>          return mm;
>   }
>
> +EXPORT_SYMBOL_GPL(mmgrab);
> +
>   /* Please note the differences between mmput and mm_release.
>    * mmput is called whenever we stop holding onto a mm_struct,
>    * error success whatever.
>

Certainly, what you did is fine, but I think it would be great if we can
fix the pvfs2 code to use only exported kernel APIs rather than forcing
people to patch their kernels. If I recall right, the SLES distribution
had some similar errors.
http://www.beowulf-underground.org/pipermail/pvfs2-developers/2005-December/001678.html
So the option for you I guess is to also disable kernel aio if you dont
wish to patch your kernel.
Thanks again for the reports,
Murali