On Mon, Oct 09, 2023 at 10:26:35AM +0530, Joey Jiao wrote: > When modprobe cmds are executed one by one, the final loaded modules > are not in fixed sequence as expected. > > Add the option to make sure modules are in fixed sequence across reboot. > > Signed-off-by: Joey Jiao <quic_jiangenj@xxxxxxxxxxx> > --- > kernel/module/Kconfig | 11 +++++++++++ > kernel/module/main.c | 6 ++++++ > 2 files changed, 17 insertions(+) > > diff --git a/kernel/module/Kconfig b/kernel/module/Kconfig > index 33a2e991f608..b45a45f31d6d 100644 > --- a/kernel/module/Kconfig > +++ b/kernel/module/Kconfig > @@ -389,4 +389,15 @@ config MODULES_TREE_LOOKUP > def_bool y > depends on PERF_EVENTS || TRACING || CFI_CLANG > > +config MODULE_LOAD_IN_SEQUENCE > + bool "Load module in sequence" > + default n > + help > + By default, modules are loaded in random sequence depending on when modprobe > + is executed. > + > + This option allows modules to be loaded in sequence if modprobe cmds are > + executed one by one in sequence. This option is helpful during syzkaller fuzzing > + to make sure module is loaded into fixed address across device reboot. > + > endif # MODULES > diff --git a/kernel/module/main.c b/kernel/module/main.c > index 98fedfdb8db5..587fd84083ae 100644 > --- a/kernel/module/main.c > +++ b/kernel/module/main.c > @@ -2593,11 +2593,17 @@ static noinline int do_init_module(struct module *mod) > * be cleaned up needs to sync with the queued work - ie > * rcu_barrier() > */ > +#ifdef CONFIG_MODULE_LOAD_IN_SEQUENCE > + llist_add(&freeinit->node, &init_free_list); > +#else > if (llist_add(&freeinit->node, &init_free_list)) > schedule_work(&init_free_wq); > +#endif How is ignoring an error ensuring ordering? > mutex_unlock(&module_mutex); > +#ifdef CONFIG_MODULE_LOAD_IN_SEQUENCE > wake_up_all(&module_wq); > +#endif Why are you making this only now be called with this new kconfig option? Luis
