The patch titled Subject: Revert "mm: kmemleak: alloc gray object for reserved region with direct map" has been added to the -mm mm-hotfixes-unstable branch. Its filename is revert-mm-kmemleak-alloc-gray-object-for-reserved-region-with-direct-map.patch

This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...

This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------ From: "Isaac J. Manjarres" isaacmanjarres@google.com Subject: Revert "mm: kmemleak: alloc gray object for reserved region with direct map" Date: Tue, 24 Jan 2023 15:02:54 -0800

This reverts commit 972fa3a7c17c9d60212e32ecc0205dc585b1e769.

Kmemleak operates by periodically scanning memory regions for pointers to allocated memory blocks to determine if they are leaked or not. However, reserved memory regions can be used for DMA transactions between a device and a CPU, and thus, wouldn't contain pointers to allocated memory blocks, making them inappropriate for kmemleak to scan. Thus, revert this commit.

Link: https://lkml.kernel.org/r/20230124230254.295589-1-isaacmanjarres@google.com Fixes: 972fa3a7c17c9 ("mm: kmemleak: alloc gray object for reserved region with direct map") Signed-off-by: Isaac J. Manjarres isaacmanjarres@google.com Cc: Calvin Zhang calvinzhang.cool@gmail.com Cc: Catalin Marinas catalin.marinas@arm.com Cc: Frank Rowand frowand.list@gmail.com Cc: Rob Herring robh+dt@kernel.org Cc: Saravana Kannan saravanak@google.com Cc: stable@vger.kernel.org [5.17+] Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

drivers/of/fdt.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-)

--- a/drivers/of/fdt.c~revert-mm-kmemleak-alloc-gray-object-for-reserved-region-with-direct-map +++ a/drivers/of/fdt.c @@ -26,7 +26,6 @@ #include <linux/serial_core.h> #include <linux/sysfs.h> #include <linux/random.h> -#include <linux/kmemleak.h>

#include <asm/setup.h> /* for COMMAND_LINE_SIZE */ #include <asm/page.h> @@ -525,12 +524,9 @@ static int __init __reserved_mem_reserve size = dt_mem_next_cell(dt_root_size_cells, &prop);

if (size && - early_init_dt_reserve_memory(base, size, nomap) == 0) { + early_init_dt_reserve_memory(base, size, nomap) == 0) pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %lu MiB\n", uname, &base, (unsigned long)(size / SZ_1M)); - if (!nomap) - kmemleak_alloc_phys(base, size, 0); - } else pr_err("Reserved memory: failed to reserve memory for node '%s': base %pa, size %lu MiB\n", uname, &base, (unsigned long)(size / SZ_1M)); _

Patches currently in -mm which might be from isaacmanjarres@google.com are

revert-mm-kmemleak-alloc-gray-object-for-reserved-region-with-direct-map.patch mm-cmac-make-kmemleak-aware-of-all-cma-regions.patch mm-cmac-delete-kmemleak-objects-when-freeing-cma-areas-to-buddy-at-boot.patch