There is no guarantee to CMA's placement, so allocating a zone specific
atomic pool from CMA might return memory from a completely different
memory zone. So stop using it.

Fixes: c84dc6e68a1d ("dma-pool: add additional coherent pools to map to gfp 
mask")
Reported-by: Jeremy Linton <jeremy.lin...@arm.com>
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulie...@suse.de>
---

An more costly alternative would be adding an option to
dma_alloc_from_contiguous() so it fails when the allocation doesn't fall
in a specific zone.

 kernel/dma/pool.c | 11 ++---------
 1 file changed, 2 insertions(+), 9 deletions(-)

diff --git a/kernel/dma/pool.c b/kernel/dma/pool.c
index 8cfa01243ed2..4bc1c46ae6ef 100644
--- a/kernel/dma/pool.c
+++ b/kernel/dma/pool.c
@@ -6,7 +6,6 @@
 #include <linux/debugfs.h>
 #include <linux/dma-direct.h>
 #include <linux/dma-noncoherent.h>
-#include <linux/dma-contiguous.h>
 #include <linux/init.h>
 #include <linux/genalloc.h>
 #include <linux/set_memory.h>
@@ -69,12 +68,7 @@ static int atomic_pool_expand(struct gen_pool *pool, size_t 
pool_size,
 
        do {
                pool_size = 1 << (PAGE_SHIFT + order);
-
-               if (dev_get_cma_area(NULL))
-                       page = dma_alloc_from_contiguous(NULL, 1 << order,
-                                                        order, false);
-               else
-                       page = alloc_pages(gfp, order);
+               page = alloc_pages(gfp, order);
        } while (!page && order-- > 0);
        if (!page)
                goto out;
@@ -118,8 +112,7 @@ static int atomic_pool_expand(struct gen_pool *pool, size_t 
pool_size,
        dma_common_free_remap(addr, pool_size);
 #endif
 free_page: __maybe_unused
-       if (!dma_release_from_contiguous(NULL, page, 1 << order))
-               __free_pages(page, order);
+       __free_pages(page, order);
 out:
        return ret;
 }
-- 
2.27.0

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