+ revert-mm-kmemleak-alloc-gray-object-for-reserved-region-with-direct-map.patch added to mm-hotfixes-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

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/revert-mm-kmemleak-alloc-gray-object-for-reserved-region-with-direct-map.patch

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