+ init-combine-blacklist-entry-allocations-in-initcall_blacklist.patch added to mm-nonmm-unstable branch

+ init-combine-blacklist-entry-allocations-in-initcall_blacklist.patch added to mm-nonmm-unstable branch

[Andrew Morton]

The patch titled
     Subject: init: combine blacklist entry allocations in initcall_blacklist()
has been added to the -mm mm-nonmm-unstable branch.  Its filename is
     init-combine-blacklist-entry-allocations-in-initcall_blacklist.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/init-combine-blacklist-entry-allocations-in-initcall_blacklist.patch

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

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------------------------------------------------------
From: Thorsten Blum <blum@kernel.org>
Subject: init: combine blacklist entry allocations in initcall_blacklist()
Date: Sun, 15 Nov 2026 15:23:21 +0100

Use a flexible array member for the function name and allocate it together
with the blacklist entry.  This removes the pointer and saves one
allocation call per blacklist entry.

Link: https://lore.kernel.org/20261115142321.96774-4-blum@kernel.org
Signed-off-by: Thorsten Blum <blum@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Breno Leitao <leitao@debian.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Sang-Heon Jeon <ekffu200098@gmail.com>
Cc: Wilson Felipe Pereira <wfelipe@google.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Mike Rapoport <rppt@kernel.org>

 init/main.c |    7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

--- a/init/main.c~init-combine-blacklist-entry-allocations-in-initcall_blacklist
+++ a/init/main.c
@@ -28,6 +28,7 @@
 #include <linux/init.h>
 #include <linux/initrd.h>
 #include <linux/memblock.h>
+#include <linux/overflow.h>
 #include <linux/acpi.h>
 #include <linux/bootconfig.h>
 #include <linux/console.h>
@@ -1275,7 +1276,7 @@ static void __init do_ctors(void)
 #ifdef CONFIG_KALLSYMS
 struct blacklist_entry {
 	struct list_head next;
-	char *buf;
+	char buf[];
 };
 
 static __initdata_or_module LIST_HEAD(blacklisted_initcalls);
@@ -1290,8 +1291,8 @@ static int __init initcall_blacklist(cha
 		size_t buf_size = strlen(str_entry) + 1;
 
 		pr_debug("blacklisting initcall %s\n", str_entry);
-		entry = memblock_alloc_or_panic(sizeof(*entry), SMP_CACHE_BYTES);
-		entry->buf = memblock_alloc_or_panic(buf_size, SMP_CACHE_BYTES);
+		entry = memblock_alloc_or_panic(struct_size(entry, buf, buf_size),
+						SMP_CACHE_BYTES);
 		strscpy(entry->buf, str_entry, buf_size);
 		list_add(&entry->next, &blacklisted_initcalls);
 	}
_

Patches currently in -mm which might be from blum@kernel.org are

init-reject-bare-rodata-parameter-before-architecture-parsing.patch
init-use-strscpy-in-do_initcalls.patch
init-use-kmalloc-in-do_initcalls.patch
init-remove-strlcat-and-sprintf-from-do_one_initcall.patch
init-use-strscpy-in-initcall_blacklist.patch
init-combine-blacklist-entry-allocations-in-initcall_blacklist.patch