+ kmemleak-test-drop-__init-to-get-better-backtrace.patch added to mm-unstable branch

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

The patch titled
     Subject: kmemleak-test: drop __init to get better backtrace
has been added to the -mm mm-unstable branch.  Its filename is
     kmemleak-test-drop-__init-to-get-better-backtrace.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/kmemleak-test-drop-__init-to-get-better-backtrace.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: Jim Cromie <jim.cromie@gmail.com>
Subject: kmemleak-test: drop __init to get better backtrace
Date: Thu, 25 May 2023 11:43:56 -0600

Drop the __init on kmemleak_test_init().  With it, the storage is
reclaimed, but then the symbol isn't available for "%pS" rendering,
and the backtrace gets a bare pointer where the actual leak happened.

unreferenced object 0xffff88800a2b0800 (size 1024):
  comm "modprobe", pid 413, jiffies 4294953430
  hex dump (first 32 bytes):
    73 02 00 00 75 01 00 68 02 00 00 01 00 00 00 04  s...u..h........
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<00000000fabad728>] kmalloc_trace+0x26/0x90
    [<00000000ef738764>] 0xffffffffc02350a2
    [<00000000004e5795>] do_one_initcall+0x43/0x210
    [<00000000d768905e>] do_init_module+0x4a/0x210
    [<0000000087135ab5>] __do_sys_finit_module+0x93/0xf0
    [<000000004fcb1fa2>] do_syscall_64+0x34/0x80
    [<00000000c73c8d9d>] entry_SYSCALL_64_after_hwframe+0x46/0xb0

with __init gone, that trace entry renders like:

    [<00000000ef738764>] kmemleak_test_init+<offset>/<size>

Link: https://lkml.kernel.org/r/20230525174356.69711-1-jim.cromie@gmail.com
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 samples/kmemleak/kmemleak-test.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/samples/kmemleak/kmemleak-test.c~kmemleak-test-drop-__init-to-get-better-backtrace
+++ a/samples/kmemleak/kmemleak-test.c
@@ -32,7 +32,7 @@ static DEFINE_PER_CPU(void *, kmemleak_t
  * Some very simple testing. This function needs to be extended for
  * proper testing.
  */
-static int __init kmemleak_test_init(void)
+static int kmemleak_test_init(void)
 {
 	struct test_node *elem;
 	int i;
_

Patches currently in -mm which might be from jim.cromie@gmail.com are

kmemleak-test-drop-__init-to-get-better-backtrace.patch