Hi Bob,

On 09/06/11 20:30, Bob Liu wrote:

On Wed, Jun 8, 2011 at 6:19 PM, Greg Ungerer[off-list ref]  wrote:

quoted

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When booting on a ColdFire (m68knommu) target the init process (or
there abouts at least) fails. Last console messages are:

...
VFS: Mounted root (romfs filesystem) readonly on device 31:0.
Freeing unused kernel memory: 52k freed (0x401aa000 - 0x401b6000)
Unable to mmap process text, errno 22

Oh, bad news. I will try to reproduce it on my board.
If you are free please enable debug in nommu.c and then we can see what
caused the problem.

Yep, with debug on:

­...
VFS: Mounted root (romfs filesystem) readonly on device 31:0.
Freeing unused kernel memory: 52k freed (0x4018c000 - 0x40198000)
==>  ádo_mmap_pgoff(,0,6780,5,1002,0)
<== do_mmap_pgoff() = -22
Unable to mmap process text, errno 22

Since I can't reproduce this problem, could you please attach the
whole dmesg log with nommu debug on or
you can step into to see why errno 22 is returned, is it returned by
do_mmap_private()?

There was no other debug messages with debug turned on in nommu.c.
(I can give you the boot msgs before this if you want, but there
was no nommu.c debug in it).

But I did trace it into do_mmap_pgoff() to see what was failing.
It fails based on the return value from:

addr = file->f_op->get_unmapped_area(file, addr, len,
                                           ¡pgoff, flags);

Thanks for this information.
But it's a callback function. I still can't know what's the problem maybe.
Would you do me a favor to do more trace to see where it callback to,
fs or some driver etc..?

Its calling to romfs_get_unmapped_area() [fs/romfs/mmap-nommu.c]. It is
being called with:

   romfs_get_unmapped_area(addr=0,len=7000,pgoff=0,flags=1002)

This is failing the first size check because isize comes back
as 0x6ca8, and this is smaller then len (0x7000). Thus returning
-EINVAL.

That code is trying to map the contents of the file /bin/init
directly from the romfs filesystem (which is in RAM). The init
binary is 0x6ca8 bytes in size (that is the isize above).

Regards
Greg


------------------------------------------------------------------------
Greg Ungerer  --  Principal Engineer        EMAIL:     gerg@snapgear.com
SnapGear Group, McAfee                      PHONE:       +61 7 3435 2888
8 Gardner Close                             FAX:         +61 7 3217 5323
Milton, QLD, 4064, Australia                WEB: http://www.SnapGear.com

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