arm64: Initialise high_memory global variable earlier

The high_memory global variable is used by
cma_declare_contiguous(.) before it is defined.

We don't notice this as we compute __pa(high_memory - 1), and it looks
like we're processing a VA from the direct linear map.

This problem becomes apparent when we flip the kernel virtual address
space and the linear map is moved to the bottom of the kernel VA space.

This patch moves the initialisation of high_memory before it used.

Cc: <stable@vger.kernel.org>
Fixes: f7426b983a6a ("mm: cma: adjust address limit to avoid hitting low/high memory boundary")
Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 5960bef0170df85916d0c1ac3b65f570f0af67ea..00e7b900ca4193e83dfa7de7dd506984afe90bce 100644 (file)
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -476,6 +476,8 @@ void __init arm64_memblock_init(void)
 
        reserve_elfcorehdr();
 
+       high_memory = __va(memblock_end_of_DRAM() - 1) + 1;
+
        dma_contiguous_reserve(arm64_dma_phys_limit);
 
        memblock_allow_resize();
@@ -502,7 +504,6 @@ void __init bootmem_init(void)
        sparse_init();
        zone_sizes_init(min, max);
 
-       high_memory = __va((max << PAGE_SHIFT) - 1) + 1;
        memblock_dump_all();
 }