+ init-kconfig-make-config-init_env_arg_limit-user-configurable.patch added to mm-nonmm-unstable branch

+ init-kconfig-make-config-init_env_arg_limit-user-configurable.patch added to mm-nonmm-unstable branch

[Andrew Morton]

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The patch titled
     Subject: init/Kconfig: make config INIT_ENV_ARG_LIMIT user-configurable
has been added to the -mm mm-nonmm-unstable branch.  Its filename is
     init-kconfig-make-config-init_env_arg_limit-user-configurable.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/init-kconfig-make-config-init_env_arg_limit-user-configurable.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: Wilson Felipe Pereira <wfelipe@google.com>
Subject: init/Kconfig: make config INIT_ENV_ARG_LIMIT user-configurable
Date: Tue, 18 Aug 2026 23:16:33 +0000

Patch series "init, arch: make command line size and init arg limit
configurable", v2.

This patch series promotes COMMAND_LINE_SIZE from arch/s390/Kconfig to
init/Kconfig to be generally available to other architectures.

In some use cases, such as netboot kernels, rootfs configurations, larger
initramfs setups, require larger sizes.  While for embedded workloads, it
can be reduced to save memory.

Since COMMAND_LINE_SIZE can be larger, it also makes sense to allow
INIT_ENV_ARG_LIMIT to be configured.


This patch (of 2):

INIT_ENV_ARG_LIMIT is defined without a prompt string (`int`), making it a
hidden Kconfig symbol that defaults to 32 (or 128 for UML) and cannot be
configured in `make menuconfig`.

Now that CONFIG_COMMAND_LINE_SIZE is configurable across all
architectures, users who select larger kernel command lines (e.g., 4096
bytes) may pass more than 32 command-line arguments or environment
variables (`foo=bar`) to `/sbin/init`.  If INIT_ENV_ARG_LIMIT remains
hardcoded at 32, any argument after the 32nd sets the panic_later flag and
causes a hard kernel panic on boot.

Add a prompt string ("Maximum number of kernel command line arguments")
and a `range 32 4096` to `config INIT_ENV_ARG_LIMIT` so that users can
configure their init argument and environment variable limit when needed,
while preserving the existing default of 32 for standard builds.

Link: https://lore.kernel.org/20260818231646.804507-1-wfelipe@google.com
Link: https://lore.kernel.org/20260818231646.804507-3-wfelipe@google.com
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: Wilson Felipe Pereira <wfelipe@google.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 init/Kconfig |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/init/Kconfig~init-kconfig-make-config-init_env_arg_limit-user-configurable
+++ a/init/Kconfig
@@ -231,9 +231,10 @@ config BROKEN_ON_SMP
 	default y
 
 config INIT_ENV_ARG_LIMIT
-	int
+	int "Maximum number of kernel command line arguments"
 	default 32 if !UML
 	default 128 if UML
+	range 32 4096
 	help
 	  Maximum of each of the number of arguments and environment
 	  variables passed to init from the kernel command line.
_

Patches currently in -mm which might be from wfelipe@google.com are

selftests-cgroup-test_zswap-wait-for-cgroup-to-unpopulate-in-test_zswap_writeback.patch
selftests-cgroup-test_zswap-fix-implicit-unsigned-promotion-bug-in-test_no_kmem_bypass.patch
init-arch-make-config_command_line_size-globally-configurable.patch
init-kconfig-make-config-init_env_arg_limit-user-configurable.patch