• T
    arm: mm: fix DMA pool affiliation check · f3d87524
    Thomas Petazzoni 提交于
    The __free_from_pool() function was changed in
    e9da6e99. Unfortunately, the test that
    checks whether the provided (start,size) is within the DMA pool has
    been improperly modified. It used to be:
    
      if (start < coherent_head.vm_start || end > coherent_head.vm_end)
    
    Where coherent_head.vm_end was non-inclusive (i.e, it did not include
    the first byte after the pool). The test has been changed to:
    
      if (start < pool->vaddr || start > pool->vaddr + pool->size)
    
    So now pool->vaddr + pool->size is inclusive (i.e, it includes the
    first byte after the pool), so the test should be >= instead of >.
    
    This bug causes the following message when freeing the *first* DMA
    coherent buffer that has been allocated, because its virtual address
    is exactly equal to pool->vaddr + pool->size :
    
    WARNING: at /home/thomas/projets/linux-2.6/arch/arm/mm/dma-mapping.c:463 __free_from_pool+0xa4/0xc0()
    freeing wrong coherent size from pool
    Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
    Cc: Marek Szyprowski <m.szyprowski@samsung.com>
    Cc: Russell King <linux@arm.linux.org.uk>
    Cc: Lior Amsalem <alior@marvell.com>
    Cc: Maen Suleiman <maen@marvell.com>
    Cc: Tawfik Bayouk <tawfik@marvell.com>
    Cc: Shadi Ammouri <shadi@marvell.com>
    Cc: Eran Ben-Avi <benavi@marvell.com>
    Cc: Yehuda Yitschak <yehuday@marvell.com>
    Cc: Nadav Haklai <nadavh@marvell.com>
    [m.szyprowski: rebased onto v3.6-rc5 and resolved conflict]
    Signed-off-by: NMarek Szyprowski <m.szyprowski@samsung.com>
    f3d87524
dma-mapping.c 43.5 KB