On Fri, Jun 15, 2012 at 5:28 PM, Greg Pearson <greg.pearson@xxxxxx> wrote: > The __alloc_memory_core_early() routine will ask memblock for a range > of memory then try to reserve it. If the reserved region array lacks > space for the new range, memblock_double_array() is called to allocate > more space for the array. If memblock is used to allocate memory for > the new array it can end up using a range that overlaps with the range > originally allocated in __alloc_memory_core_early(), leading to possible > data corruption. > > With this patch memblock_double_array() now calls memblock_find_in_range() > with a narrowed candidate range so any memory allocated will not overlap > with the original range that was being reserved. The range is narrowed by > passing in both the starting and ending address of the previously allocated > range. Then the range above the ending address is searched and if a candidate > is not found, the range below the starting address is searched. > > Changes from v1: (based on comments from Yinghai Lu) > - use obase instead of base in memblock_add_region() for exclude start address > - pass in both the starting and ending address of the exclude range to > memblock_double_array() > - have memblock_double_array() search above the exclude ending address > and below the exclude starting address for a free range > > Signed-off-by: Greg Pearson <greg.pearson@xxxxxx> found more problem, please check -v3 also add cc to Ben. Thanks Yinghai
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memblock_double_array_fix.patch
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