[PATCH] memory: emif: Remove const from min_tck allocation type

[PATCH] memory: emif: Remove const from min_tck allocation type

[Kees Cook]

From: Kees Cook <kees+treewide@kernel.org>

In preparation for making the devm_kmalloc family of allocators type
aware, we need to make sure that the returned type from the allocation
matches the type of the variable being assigned. (Before, the allocator
would always return "void *", which can be implicitly cast to any
pointer type.)

The size was taken from "*pd->min_tck", so the converted allocation type
would be "const struct lpddr2_min_tck *", as "pd->min_tck" points to
const. The allocation is a writable copy assigned to a "void *" and then
memcpy()ed into, so name the unqualified type directly, for a converted
allocation type of "struct lpddr2_min_tck *". As there is no general way
to remove const qualifiers, this keeps the allocation type matching how
the memory is used. No change in allocation size results.

Build tested ARCH=x86_64 allmodconfig with GCC 16.2.0:
drivers/memory/emif.o

Assisted-by: LLM coccinelle
Signed-off-by: Kees Cook <kees+treewide@kernel.org>
---
Cc: Santosh Shilimkar <ssantosh@kernel.org>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
---
 drivers/memory/emif.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/memory/emif.c b/drivers/memory/emif.c
index 2fadad0666b1..1be543a5b1e5 100644
--- a/drivers/memory/emif.c
+++ b/drivers/memory/emif.c
@@ -1062,7 +1062,8 @@ static struct emif_data *get_device_details(
 	}
 
 	if (pd->min_tck) {
-		temp = devm_kzalloc(dev, sizeof(*pd->min_tck), GFP_KERNEL);
+		temp = devm_kzalloc(dev, sizeof(struct lpddr2_min_tck),
+				    GFP_KERNEL);
 		if (temp) {
 			memcpy(temp, pd->min_tck, sizeof(*pd->min_tck));
 			pd->min_tck = temp;
-- 
2.34.1

Re: [PATCH] memory: emif: Remove const from min_tck allocation type

[Krzysztof Kozlowski]

On Thu, 17 Sep 2026 14:12:54 -0700, Kees Cook wrote:
> In preparation for making the devm_kmalloc family of allocators type
> aware, we need to make sure that the returned type from the allocation
> matches the type of the variable being assigned. (Before, the allocator
> would always return "void *", which can be implicitly cast to any
> pointer type.)
> 
> The size was taken from "*pd->min_tck", so the converted allocation type
> would be "const struct lpddr2_min_tck *", as "pd->min_tck" points to
> const. The allocation is a writable copy assigned to a "void *" and then
> memcpy()ed into, so name the unqualified type directly, for a converted
> allocation type of "struct lpddr2_min_tck *". As there is no general way
> to remove const qualifiers, this keeps the allocation type matching how
> the memory is used. No change in allocation size results.
> 
> [...]

Applied, thanks!

[1/1] memory: emif: Remove const from min_tck allocation type
      https://git.kernel.org/krzk/linux-mem-ctrl/c/e3049c9edd4181e5ce4f83bbac4b611d921f45ff

Best regards,
-- 
Krzysztof Kozlowski <krzk@kernel.org>