On Thu, 29 Sep 2011, Rob Herring wrote:

Nicolas,

On 09/23/2011 08:32 AM, Nicolas Pitre wrote:

quoted

Russell, please pull

	git://git.linaro.org/people/nico/linux vmalloc

This patch series removes all instances of mach/vmalloc.h in order to
have a more unified memory map across all ARM architectures.  To do so,
the static mappings are moved inside the vmalloc area.  And finally this
allows for a generic optimization to ioremap where static mappings are
reused whenever possible, using common code instead of having this
duplicated in a couple places.

I've found that this breaks on versatile (ab and pb) under QEMU. The
commit causing it is:

commit e0438e2f333005c217a2f65aacab23a39261c64c
Author: Nicolas Pitre [off-list ref]
Date:   Thu Aug 25 00:35:59 2011 -0400

    ARM: move iotable mappings within the vmalloc region

    In order to remove the build time variation between different SOCs with
    regards to VMALLOC_END, the iotable mappings are now allocated inside
    the vmalloc region.  This allows for VMALLOC_END to be identical across
    all machines.

    The value for VMALLOC_END is now set to 0xff000000 which is right where
    the consistent DMA area starts.

    To accommodate all static mappings on machines with possible highmem
usage,
    the default vmalloc area size is changed to 240 MB so that VMALLOC_START
    is no higher than 0xf0000000 by default in that case.

    Signed-off-by: Nicolas Pitre [off-list ref]


It dies after "Data cache writeback" with BUG at vmalloc.c:1139.

Interesting.  Looks like Versatile might have overlapping map_desc 
entries.

Could you add the following line at the top of vm_area_add_early() in 
mm/vmalloc.c to display the area being added:

  printk("%s: called with addr=%p size=0x%lx\n", __func__, vm->addr, vm->size);

This should help determine which entry is wrong.


Nicolas