Re: [PATCH v3 1/4] module: Correct wake up of module_wq

From: David Hildenbrand
Date: Mon Oct 17 2022 - 03:27:08 EST


On 16.10.22 14:30, Petr Pavlu wrote:
The module_wq wait queue has only non-exclusive waiters and all waits
are interruptible, therefore for consistency use wake_up_interruptible()
to wake its waiters.

Suggested-by: Petr Mladek <pmladek@xxxxxxxx>
Reviewed-by: Petr Mladek <pmladek@xxxxxxxx>
Signed-off-by: Petr Pavlu <petr.pavlu@xxxxxxxx>
---
kernel/module/main.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/kernel/module/main.c b/kernel/module/main.c
index d02d39c7174e..a12e177ea81f 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -764,7 +764,7 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
free_module(mod);
/* someone could wait for the module in add_unformed_module() */
- wake_up_all(&module_wq);
+ wake_up_interruptible(&module_wq);
return 0;
out:
mutex_unlock(&module_mutex);
@@ -2522,7 +2522,7 @@ static noinline int do_init_module(struct module *mod)
schedule_work(&init_free_wq);
mutex_unlock(&module_mutex);
- wake_up_all(&module_wq);
+ wake_up_interruptible(&module_wq);
return 0;
@@ -2538,7 +2538,7 @@ static noinline int do_init_module(struct module *mod)
klp_module_going(mod);
ftrace_release_mod(mod);
free_module(mod);
- wake_up_all(&module_wq);
+ wake_up_interruptible(&module_wq);
return ret;
}
@@ -2879,7 +2879,7 @@ static int load_module(struct load_info *info, const char __user *uargs,
/* Unlink carefully: kallsyms could be walking list. */
list_del_rcu(&mod->list);
mod_tree_remove(mod);
- wake_up_all(&module_wq);
+ wake_up_interruptible(&module_wq);
/* Wait for RCU-sched synchronizing before releasing mod->list. */
synchronize_rcu();
mutex_unlock(&module_mutex);

Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>

--
Thanks,

David / dhildenb