+ mm-kmemleak-check-physical-address-when-scan.patch added to mm-unstable branch

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

The patch titled
     Subject: mm: kmemleak: check physical address when scan
has been added to the -mm mm-unstable branch.  Its filename is
     mm-kmemleak-check-physical-address-when-scan.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-kmemleak-check-physical-address-when-scan.patch

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

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------------------------------------------------------
From: Patrick Wang <patrick.wang.shcn@gmail.com>
Subject: mm: kmemleak: check physical address when scan
Date: Sat, 11 Jun 2022 11:55:51 +0800

Check the physical address of objects for its boundary when scan instead
of in kmemleak_*_phys().

Link: https://lkml.kernel.org/r/20220611035551.1823303-5-patrick.wang.shcn@gmail.com
Fixes: 23c2d497de21 ("mm: kmemleak: take a full lowmem check in kmemleak_*_phys()")
Signed-off-by: Patrick Wang <patrick.wang.shcn@gmail.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Yee Lee <yee.lee@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/kmemleak.c |   17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

--- a/mm/kmemleak.c~mm-kmemleak-check-physical-address-when-scan
+++ a/mm/kmemleak.c
@@ -1184,7 +1184,7 @@ void __ref kmemleak_alloc_phys(phys_addr
 {
 	pr_debug("%s(0x%pa, %zu)\n", __func__, &phys, size);
 
-	if (PHYS_PFN(phys) >= min_low_pfn && PHYS_PFN(phys) < max_low_pfn)
+	if (kmemleak_enabled)
 		/*
 		 * Create object with OBJECT_PHYS flag and
 		 * assume min_count 0.
@@ -1204,7 +1204,7 @@ void __ref kmemleak_free_part_phys(phys_
 {
 	pr_debug("%s(0x%pa)\n", __func__, &phys);
 
-	if (PHYS_PFN(phys) >= min_low_pfn && PHYS_PFN(phys) < max_low_pfn)
+	if (kmemleak_enabled)
 		delete_object_part((unsigned long)phys, size, true);
 }
 EXPORT_SYMBOL(kmemleak_free_part_phys);
@@ -1218,7 +1218,7 @@ void __ref kmemleak_ignore_phys(phys_add
 {
 	pr_debug("%s(0x%pa)\n", __func__, &phys);
 
-	if (PHYS_PFN(phys) >= min_low_pfn && PHYS_PFN(phys) < max_low_pfn)
+	if (kmemleak_enabled)
 		make_black_object((unsigned long)phys, true);
 }
 EXPORT_SYMBOL(kmemleak_ignore_phys);
@@ -1493,6 +1493,17 @@ static void kmemleak_scan(void)
 			dump_object_info(object);
 		}
 #endif
+
+		/* ignore objects outside lowmem (paint them black) */
+		if ((object->flags & OBJECT_PHYS) &&
+		   !(object->flags & OBJECT_NO_SCAN)) {
+			unsigned long phys = object->pointer;
+
+			if (PHYS_PFN(phys) < min_low_pfn ||
+			    PHYS_PFN(phys + object->size) >= max_low_pfn)
+				__paint_it(object, KMEMLEAK_BLACK);
+		}
+
 		/* reset the reference count (whiten the object) */
 		object->count = 0;
 		if (color_gray(object) && get_object(object))
_

Patches currently in -mm which might be from patrick.wang.shcn@gmail.com are

mm-kmemleak-remove-kmemleak_not_leak_phys-and-the-min_count-argument-to-kmemleak_alloc_phys.patch
mm-kmemleak-add-object_phys-flag-for-objects-allocated-with-physical-address.patch
mm-kmemleak-add-rbtree-and-store-physical-address-for-objects-allocated-with-pa.patch
mm-kmemleak-check-physical-address-when-scan.patch