The fixed parameter to cma_declare_contiguous() tells the function whether the given base address must be honoured or should be considered as a hint only. The API considers a zero base address as meaning any base address, which must never be considered as a fixed value. Part of the implementation correctly checks both fixed and base != 0, but two locations check the fixed value only. Set fixed to false when base is 0 to fix that and simplify the code. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx> --- mm/cma.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/mm/cma.c b/mm/cma.c index 16c6650..6b14346 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -239,6 +239,9 @@ int __init cma_declare_contiguous(phys_addr_t base, size = ALIGN(size, alignment); limit &= ~(alignment - 1); + if (!base) + fixed = false; + /* size should be aligned with order_per_bit */ if (!IS_ALIGNED(size >> PAGE_SHIFT, 1 << order_per_bit)) return -EINVAL; @@ -262,7 +265,7 @@ int __init cma_declare_contiguous(phys_addr_t base, } /* Reserve memory */ - if (base && fixed) { + if (fixed) { if (memblock_is_region_reserved(base, size) || memblock_reserve(base, size) < 0) { ret = -EBUSY; -- 2.0.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>