Merge patch series "nios2: Add architecture support for clone3"

Simon Schuster <schuster.simon@siemens-energy.com> says:

This series adds support for the clone3 system call to the nios2
architecture. This addresses the build-time warning "warning: clone3()
entry point is missing, please fix" introduced in 505d66d1abfb9
("clone3: drop __ARCH_WANT_SYS_CLONE3 macro"). The implementation passes
the relevant clone3 tests of kselftest when applied on top of
next-20250815:

	./run_kselftest.sh
	TAP version 13
	1..4
	# selftests: clone3: clone3
	ok 1 selftests: clone3: clone3
	# selftests: clone3: clone3_clear_sighand
	ok 2 selftests: clone3: clone3_clear_sighand
	# selftests: clone3: clone3_set_tid
	ok 3 selftests: clone3: clone3_set_tid
	# selftests: clone3: clone3_cap_checkpoint_restore
	ok 4 selftests: clone3: clone3_cap_checkpoint_restore

The series also includes a small patch to kernel/fork.c that ensures
that clone_flags are passed correctly on architectures where unsigned
long is insufficient to store the u64 clone_flags. It is marked as a fix
for stable backporting.

As requested, in v2, this series now further tries to correct this type
error throughout the whole code base. Thus, it now touches a larger
number of subsystems and all architectures.

Therefore, another test was performed for ARCH=x86_64 (as a
representative for 64-bit architectures). Here, the series builds cleanly
without warnings on defconfig with CONFIG_SECURITY_APPARMOR=y and
CONFIG_SECURITY_TOMOYO=y (to compile-check the LSM-related changes).
The build further successfully passes testing/selftests/clone3 (with the
patch from 20241105062948.1037011-1-zhouyuhang1010@163.com to prepare
clone3_cap_checkpoint_restore for compatibility with the newer libcap
version on my system).

* patches from https://lore.kernel.org/20250901-nios2-implement-clone3-v2-0-53fcf5577d57@siemens-energy.com:
  nios2: implement architecture-specific portion of sys_clone3
  arch: copy_thread: pass clone_flags as u64
  copy_process: pass clone_flags as u64 across calltree
  copy_sighand: Handle architectures where sizeof(unsigned long) < sizeof(u64)

Link: https://lore.kernel.org/20250901-nios2-implement-clone3-v2-0-53fcf5577d57@siemens-energy.com
Signed-off-by: Christian Brauner <brauner@kernel.org>

4 files changed, 4 insertions, 4 deletions

diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c
index 8e1cc229b41b..ba39cfe0cd08 100644
--- a/security/apparmor/lsm.c
+++ b/security/apparmor/lsm.c
@@ -112,7 +112,7 @@ static void apparmor_task_free(struct task_struct *task)
 }
 
 static int apparmor_task_alloc(struct task_struct *task,
-			       unsigned long clone_flags)
+			       u64 clone_flags)
 {
 	struct aa_task_ctx *new = task_ctx(task);
 
diff --git a/security/security.c b/security/security.c
index ad163f06bf7a..a769140553bc 100644
--- a/security/security.c
+++ b/security/security.c
@@ -3185,7 +3185,7 @@ int security_file_truncate(struct file *file)
  *
  * Return: Returns a zero on success, negative values on failure.
  */
-int security_task_alloc(struct task_struct *task, unsigned long clone_flags)
+int security_task_alloc(struct task_struct *task, u64 clone_flags)
 {
 	int rc = lsm_task_alloc(task);
 
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index c95a5874bf7d..bb016dd511c1 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -4144,7 +4144,7 @@ static int selinux_file_open(struct file *file)
 /* task security operations */
 
 static int selinux_task_alloc(struct task_struct *task,
-			      unsigned long clone_flags)
+			      u64 clone_flags)
 {
 	u32 sid = current_sid();
 
diff --git a/security/tomoyo/tomoyo.c b/security/tomoyo/tomoyo.c
index d6ebcd9db80a..48fc59d38ab2 100644
--- a/security/tomoyo/tomoyo.c
+++ b/security/tomoyo/tomoyo.c
@@ -514,7 +514,7 @@ struct lsm_blob_sizes tomoyo_blob_sizes __ro_after_init = {
  * Returns 0.
  */
 static int tomoyo_task_alloc(struct task_struct *task,
-			     unsigned long clone_flags)
+			     u64 clone_flags)
 {
 	struct tomoyo_task *old = tomoyo_task(current);
 	struct tomoyo_task *new = tomoyo_task(task);