Changbin Du 6a3d4afc54 modules: wait do_free_init correctly ... [ Upstream commit 8f8cd6c0a43ed637e620bbe45a8d0e0c2f4d5130 ] The synchronization here is to ensure the ordering of freeing of a module init so that it happens before W+X checking. It is worth noting it is not that the freeing was not happening, it is just that our sanity checkers raced against the permission checkers which assume init memory is already gone. Commit 1a7b7d9220 ("modules: Use vmalloc special flag") moved calling do_free_init() into a global workqueue instead of relying on it being called through call_rcu(..., do_free_init), which used to allowed us call do_free_init() asynchronously after the end of a subsequent grace period. The move to a global workqueue broke the gaurantees for code which needed to be sure the do_free_init() would complete with rcu_barrier(). To fix this callers which used to rely on rcu_barrier() must now instead use flush_work(&init_free_wq). Without this fix, we still could encounter false positive reports in W+X checking since the rcu_barrier() here can not ensure the ordering now. Even worse, the rcu_barrier() can introduce significant delay. Eric Chanudet reported that the rcu_barrier introduces ~0.1s delay on a PREEMPT_RT kernel. [ 0.291444] Freeing unused kernel memory: 5568K [ 0.402442] Run /sbin/init as init process With this fix, the above delay can be eliminated. Link: https://lkml.kernel.org/r/20240227023546.2490667-1-changbin.du@huawei.com Fixes: 1a7b7d9220 ("modules: Use vmalloc special flag") Signed-off-by: Changbin Du <changbin.du@huawei.com> Tested-by: Eric Chanudet <echanude@redhat.com> Acked-by: Luis Chamberlain <mcgrof@kernel.org> Cc: Xiaoyi Su <suxiaoyi@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2024-03-26 18:21:31 -04:00
..
bpf	bpf: Fix stackmap overflow check on 32-bit arches	2024-03-26 18:21:22 -04:00
cgroup	cgroup: Remove duplicates in cgroup v1 tasks file	2023-10-19 23:05:37 +02:00
configs	drivers/char: remove /dev/kmem for good	2021-05-07 00:26:34 -07:00
debug	kdb: Fix a potential buffer overflow in kdb_local()	2024-01-25 14:52:54 -08:00
dma	dma-mapping: clear dev->dma_mem to NULL after freeing it	2024-01-25 14:52:38 -08:00
entry	entry/rcu: Check TIF_RESCHED _after_ delayed RCU wake-up	2023-03-30 12:47:51 +02:00
events	perf: Fix the nr_addr_filters fix	2024-02-23 08:54:52 +01:00
futex	futex: Don't include process MM in futex key on no-MMU	2023-11-20 11:08:13 +01:00
gcov	gcov: add support for checksum field	2022-12-31 13:14:47 +01:00
irq	genirq/generic_chip: Make irq_remove_generic_chip() irqdomain aware	2023-11-28 16:56:30 +00:00
kcsan	kcsan: Don't expect 64 bits atomic builtins from 32 bits architectures	2023-07-23 13:47:12 +02:00
livepatch	livepatch: Fix missing newline character in klp_resolve_symbols()	2023-11-20 11:08:25 +01:00
locking	lockdep: Fix block chain corruption	2023-12-03 07:31:23 +01:00
power	PM: hibernate: Enforce ordering during image compression/decompression	2024-02-23 08:54:23 +01:00
printk	printk: Consolidate console deferred printing	2023-09-23 11:09:59 +02:00
rcu	rcu-tasks: Provide rcu_trace_implies_rcu_gp()	2024-03-26 18:21:11 -04:00
sched	sched/fair: Take the scheduling domain into account in select_idle_core()	2024-03-26 18:21:15 -04:00
time	timekeeping: Fix cross-timestamp interpolation for non-x86	2024-03-26 18:21:15 -04:00
trace	bpf: Remove trace_printk_lock	2024-03-01 13:21:43 +01:00
.gitignore	.gitignore: prefix local generated files with a slash	2021-05-02 00:43:35 +09:00
Kconfig.freezer	…
Kconfig.hz	…
Kconfig.locks	locking/rwlock: Provide RT variant	2021-08-17 17:50:51 +02:00
Kconfig.preempt	sched/core: Disable CONFIG_SCHED_CORE by default	2021-06-28 22:43:05 +02:00
Makefile	futex: Move to kernel/futex/	2022-12-31 13:14:04 +01:00
acct.c	acct: fix potential integer overflow in encode_comp_t()	2022-12-31 13:14:40 +01:00
async.c	async: Introduce async_schedule_dev_nocall()	2024-02-23 08:54:25 +01:00
audit.c	audit: Send netlink ACK before setting connection in auditd_set	2024-02-23 08:54:37 +01:00
audit.h	audit: log AUDIT_TIME_* records only from rules	2022-04-08 14:23:06 +02:00
audit_fsnotify.c	audit: fix potential double free on error path from fsnotify_add_inode_mark	2022-08-31 17:16:33 +02:00
audit_tree.c	audit: move put_tree() to avoid trim_trees refcount underflow and UAF	2021-08-24 18:52:36 -04:00
audit_watch.c	audit: don't WARN_ON_ONCE(!current->mm) in audit_exe_compare()	2023-11-28 16:56:27 +00:00
auditfilter.c	lsm: separate security_task_getsecid() into subjective and objective variants	2021-03-22 15:23:32 -04:00
auditsc.c	audit: fix possible soft lockup in __audit_inode_child()	2023-09-19 12:22:39 +02:00
backtracetest.c	…
bounds.c	…
capability.c	capability: handle idmapped mounts	2021-01-24 14:27:16 +01:00
cfi.c	cfi: Fix __cfi_slowpath_diag RCU usage with cpuidle	2022-06-22 14:22:04 +02:00
compat.c	sched_getaffinity: don't assume 'cpumask_size()' is fully initialized	2023-04-05 11:24:53 +02:00
configs.c	…
context_tracking.c	…
cpu.c	hrtimers: Push pending hrtimers away from outgoing CPU earlier	2023-12-13 18:36:31 +01:00
cpu_pm.c	PM: cpu: Make notifier chain use a raw_spinlock_t	2021-08-16 18:55:32 +02:00
crash_core.c	kernel/crash_core: suppress unknown crashkernel parameter warning	2021-12-29 12:28:49 +01:00
crash_dump.c	…
cred.c	cred: switch to using atomic_long_t	2023-12-20 15:17:37 +01:00
delayacct.c	delayacct: Add sysctl to enable at runtime	2021-05-12 11:43:25 +02:00
dma.c	…
exec_domain.c	…
exit.c	exit: Use READ_ONCE() for all oops/warn limit reads	2023-02-01 08:27:22 +01:00
extable.c	…
fail_function.c	kernel/fail_function: fix memory leak with using debugfs_lookup()	2023-03-11 13:57:38 +01:00
fork.c	kernel/fork: beware of __put_task_struct() calling context	2023-09-23 11:09:55 +02:00
freezer.c	sched: Add get_current_state()	2021-06-18 11:43:08 +02:00
gen_kheaders.sh	kbuild: clean up ${quiet} checks in shell scripts	2021-05-27 04:01:50 +09:00
groups.c	groups: simplify struct group_info allocation	2021-02-26 09:41:03 -08:00
hung_task.c	Merge branch 'akpm' (patches from Andrew)	2021-07-02 12:08:10 -07:00
iomem.c	…
irq_work.c	irq_work: Make irq_work_queue() NMI-safe again	2021-06-10 10:00:08 +02:00
jump_label.c	jump_label: Fix jump_label_text_reserved() vs __init	2021-07-05 10:46:20 +02:00
kallsyms.c	kallsyms: Make kallsyms_on_each_symbol generally available	2023-12-13 18:36:45 +01:00
kcmp.c	…
kcov.c	…
kexec.c	kernel: kexec: copy user-array safely	2023-11-28 16:56:16 +00:00
kexec_core.c	kexec: fix a memory leak in crash_shrink_memory()	2023-07-23 13:46:52 +02:00
kexec_elf.c	…
kexec_file.c	kexec: support purgatories with .text.hot sections	2023-06-21 15:59:14 +02:00
kexec_internal.h	panic, kexec: make __crash_kexec() NMI safe	2023-04-20 12:13:57 +02:00
kheaders.c	kheaders: Use array declaration instead of char	2023-05-11 23:00:17 +09:00
kmod.c	modules: add CONFIG_MODPROBE_PATH	2021-05-07 00:26:33 -07:00
kprobes.c	kprobes: Fix to handle forcibly unoptimized kprobes on freeing_list	2024-01-25 14:52:31 -08:00
ksysfs.c	kexec: turn all kexec_mutex acquisitions into trylocks	2023-04-20 12:13:57 +02:00
kthread.c	kthread: add the helper function kthread_run_on_cpu()	2023-03-30 12:47:42 +02:00
latencytop.c	…
module-internal.h	…
module.c	modules: wait do_free_init correctly	2024-03-26 18:21:31 -04:00
module_signature.c	module: harden ELF info handling	2021-01-19 10:24:45 +01:00
module_signing.c	module: harden ELF info handling	2021-01-19 10:24:45 +01:00
notifier.c	notifier: Remove atomic_notifier_call_chain_robust()	2021-08-16 18:55:32 +02:00
nsproxy.c	memcg: enable accounting for new namesapces and struct nsproxy	2021-09-03 09:58:12 -07:00
padata.c	crypto: pcrypt - Fix hungtask for PADATA_RESET	2023-11-28 16:56:18 +00:00
panic.c	exit: Use READ_ONCE() for all oops/warn limit reads	2023-02-01 08:27:22 +01:00
params.c	params: lift param_set_uint_minmax to common code	2021-08-16 14:42:22 +02:00
pid.c	kernel/pid.c: implement additional checks upon pidfd_create() parameters	2021-08-10 12:53:07 +02:00
pid_namespace.c	rcu-tasks: Fix synchronize_rcu_tasks() VS zap_pid_ns_processes()	2023-03-10 09:39:09 +01:00
profile.c	profiling: fix shift too large makes kernel panic	2022-08-17 14:24:04 +02:00
ptrace.c	ptrace: Reimplement PTRACE_KILL by always sending SIGKILL	2022-06-09 10:22:29 +02:00
range.c	…
reboot.c	kernel/reboot: emergency_restart: Set correct system_state	2023-11-28 16:56:31 +00:00
regset.c	…
relay.c	relayfs: fix out-of-bounds access in relay_file_read	2023-05-11 23:00:18 +09:00
resource.c	dax/kmem: Fix leak of memory-hotplug resources	2023-03-10 09:40:08 +01:00
resource_kunit.c	…
rseq.c	rseq: Remove broken uapi field layout on 32-bit little endian	2022-04-08 14:23:10 +02:00
scftorture.c	scftorture: Forgive memory-allocation failure if KASAN	2023-09-23 11:09:55 +02:00
scs.c	scs: Release kasan vmalloc poison in scs_free process	2021-11-18 19:16:29 +01:00
seccomp.c	seccomp: Invalidate seccomp mode to catch death failures	2022-02-16 12:56:38 +01:00
signal.c	signal handling: don't use BUG_ON() for debugging	2022-07-21 21:24:42 +02:00
smp.c	locking/csd_lock: Change csdlock_debug from early_param to __setup	2022-08-17 14:24:24 +02:00
smpboot.c	smpboot: Replace deprecated CPU-hotplug functions.	2021-08-10 14:57:42 +02:00
smpboot.h	…
softirq.c	timers/nohz: Last resort update jiffies on nohz_full IRQ entry	2023-08-16 18:22:04 +02:00
stackleak.c	gcc-plugins/stackleak: Use noinstr in favor of notrace	2022-02-23 12:03:07 +01:00
stacktrace.c	stacktrace: move filter_irq_stacks() to kernel/stacktrace.c	2022-04-13 20:59:28 +02:00
static_call.c	static_call: Don't make __static_call_return0 static	2022-04-13 20:59:28 +02:00
static_call_inline.c	static_call: Don't make __static_call_return0 static	2022-04-13 20:59:28 +02:00
stop_machine.c	stop_machine: Add caller debug info to queue_stop_cpus_work	2021-03-23 16:01:58 +01:00
sys.c	getrusage: use sig->stats_lock rather than lock_task_sighand()	2024-03-15 10:48:22 -04:00
sys_ni.c	kernel/sys_ni: add compat entry for fadvise64_64	2022-08-31 17:16:33 +02:00
sysctl-test.c	kernel/sysctl-test: Remove some casts which are no-longer required	2021-06-23 16:41:24 -06:00
sysctl.c	sched/rt: Disallow writing invalid values to sched_rt_period_us	2024-03-01 13:21:43 +01:00
task_work.c	kasan: record task_work_add() call stack	2021-04-30 11:20:42 -07:00
taskstats.c	…
test_kprobes.c	…
torture.c	torture: Fix hang during kthread shutdown phase	2023-08-30 16:18:19 +02:00
tracepoint.c	tracepoint: Fix kerneldoc comments	2021-08-16 11:39:51 -04:00
tsacct.c	taskstats: Cleanup the use of task->exit_code	2022-01-27 11:05:35 +01:00
ucount.c	ucounts: Handle wrapping in is_ucounts_overlimit	2022-02-23 12:03:20 +01:00
uid16.c	…
uid16.h	…
umh.c	kernel/umh.c: fix some spelling mistakes	2021-05-07 00:26:34 -07:00
up.c	A set of locking related fixes and updates:	2021-05-09 13:07:03 -07:00
user-return-notifier.c	…
user.c	fs/epoll: use a per-cpu counter for user's watches count	2021-09-08 11:50:27 -07:00
user_namespace.c	ucounts: Fix systemd LimitNPROC with private users regression	2022-03-08 19:12:42 +01:00
usermode_driver.c	Merge branch 'work.namei' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2021-07-03 11:41:14 -07:00
utsname.c	…
utsname_sysctl.c	…
watch_queue.c	kernel: watch_queue: copy user-array safely	2023-11-28 16:56:16 +00:00
watchdog.c	watchdog: move softlockup_panic back to early_param	2023-11-28 16:56:28 +00:00
watchdog_hld.c	watchdog/perf: more properly prevent false positives with turbo modes	2023-07-23 13:46:52 +02:00
workqueue.c	Revert "workqueue: remove unused cancel_work()"	2023-12-08 08:48:03 +01:00
workqueue_internal.h	workqueue: Assign a color to barrier work items	2021-08-17 07:49:10 -10:00