From b40680220b13f79eeb900aca436270b86a9623bb Mon Sep 17 00:00:00 2001
From: "Isaac J. Manjarres" <isaacmanjarres@google.com>
Date: Tue, 24 Jan 2023 15:02:54 -0800
Subject: [PATCH] Revert "mm: kmemleak: alloc gray object for reserved region
 with direct map"

commit 8ef852f1cb426a5812aee700d3b4297aaa426acc upstream.

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>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Calvin Zhang <calvinzhang.cool@gmail.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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/of/fdt.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index f08b25195ae79..d1a68b6d03b3f 100644
--- a/drivers/of/fdt.c
+++ b/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_reg(unsigned long node,
 		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));
-- 
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