From 59f9415ffb9759e950d775f4c400f747b332cc02 Mon Sep 17 00:00:00 2001 From: Arjan van de Ven Date: Wed, 30 Jul 2008 12:49:02 -0700 Subject: modules: extend initcall_debug functionality to the module loader The kernel has this really nice facility where if you put "initcall_debug" on the kernel commandline, it'll print which function it's going to execute just before calling an initcall, and then after the call completes it will 1) print if it had an error code 2) checks for a few simple bugs (like leaving irqs off) and 3) print how long the init call took in milliseconds. While trying to optimize the boot speed of my laptop, I have been loving number 3 to figure out what to optimize... ... and then I wished that the same thing was done for module loading. This patch makes the module loader use this exact same functionality; it's a logical extension in my view (since modules are just sort of late binding initcalls anyway) and so far I've found it quite useful in finding where things are too slow in my boot. Signed-off-by: Arjan van de Ven Signed-off-by: Andrew Morton Signed-off-by: Rusty Russell --- kernel/module.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/module.c') diff --git a/kernel/module.c b/kernel/module.c index 61d212120df..08864d257eb 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -2288,7 +2288,7 @@ sys_init_module(void __user *umod, /* Start the module */ if (mod->init != NULL) - ret = mod->init(); + ret = do_one_initcall(mod->init); if (ret < 0) { /* Init routine failed: abort. Try to protect us from buggy refcounters. */ -- cgit v1.2.3-70-g09d2 From ffb4ba76a25ab6c9deeec33e4f58395586ca747c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Mon, 25 Aug 2008 11:10:26 -0700 Subject: [module] Don't let gcc inline load_module() 'load_module()' is a complex function that contains all the ELF section logic, and inlining it is utterly insane. But gcc will do it, simply because there is only one call-site. As a result, all the stack space that is allocated for all the work to load the module will still be active when we actually call the module init sequence, and the deep call chain makes stack overflows happen. And stack overflows are really hard to debug, because they not only corrupt random pages below the stack, but also corrupt the thread_info structure that is allocated under the stack. In this case, Alan Brunelle reported some crazy oopses at bootup, after loading the processor module that ends up doing complex ACPI stuff and has quite a deep callchain. This should fix it, and is the sane thing to do regardless. Cc: Alan D. Brunelle Cc: Arjan van de Ven Cc: Rusty Russell Signed-off-by: Linus Torvalds --- kernel/module.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/module.c') diff --git a/kernel/module.c b/kernel/module.c index 08864d257eb..9db11911e04 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1799,7 +1799,7 @@ static void *module_alloc_update_bounds(unsigned long size) /* Allocate and load the module: note that size of section 0 is always zero, and we rely on this for optional sections. */ -static struct module *load_module(void __user *umod, +static noinline struct module *load_module(void __user *umod, unsigned long len, const char __user *uargs) { -- cgit v1.2.3-70-g09d2