diff options
Diffstat (limited to 'kernels/linux-libre-rt/module-init-wait-3.6.patch')
| -rw-r--r-- | kernels/linux-libre-rt/module-init-wait-3.6.patch | 77 |
1 files changed, 0 insertions, 77 deletions
diff --git a/kernels/linux-libre-rt/module-init-wait-3.6.patch b/kernels/linux-libre-rt/module-init-wait-3.6.patch deleted file mode 100644 index 1bcfd2491..000000000 --- a/kernels/linux-libre-rt/module-init-wait-3.6.patch +++ /dev/null @@ -1,77 +0,0 @@ -From: Rusty Russell <rusty@rustcorp.com.au> -Date: Fri, 28 Sep 2012 05:01:03 +0000 (+0930) -Subject: module: wait when loading a module which is currently initializing. -X-Git-Tag: v3.7-rc1~2^2~32 -X-Git-Url: http://git.kernel.org/?p=linux%2Fkernel%2Fgit%2Ftorvalds%2Flinux-2.6.git;a=commitdiff_plain;h=9bb9c3be568346538 - -module: wait when loading a module which is currently initializing. - -The original module-init-tools module loader used a fnctl lock on the -.ko file to avoid attempts to simultaneously load a module. -Unfortunately, you can't get an exclusive fcntl lock on a read-only -fd, making this not work for read-only mounted filesystems. -module-init-tools has a hacky sleep-and-loop for this now. - -It's not that hard to wait in the kernel, and only return -EEXIST once -the first module has finished loading (or continue loading the module -if the first one failed to initialize for some reason). It's also -consistent with what we do for dependent modules which are still loading. - -Suggested-by: Lucas De Marchi <lucas.demarchi@profusion.mobi> -Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> ---- - -diff --git a/kernel/module.c b/kernel/module.c -index 63cf6e7..74bc195 100644 ---- a/kernel/module.c -+++ b/kernel/module.c -@@ -2845,6 +2845,20 @@ static int post_relocation(struct module *mod, const struct load_info *info) - return module_finalize(info->hdr, info->sechdrs, mod); - } - -+/* Is this module of this name done loading? No locks held. */ -+static bool finished_loading(const char *name) -+{ -+ struct module *mod; -+ bool ret; -+ -+ mutex_lock(&module_mutex); -+ mod = find_module(name); -+ ret = !mod || mod->state != MODULE_STATE_COMING; -+ mutex_unlock(&module_mutex); -+ -+ return ret; -+} -+ - /* 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, -@@ -2852,7 +2866,7 @@ static struct module *load_module(void __user *umod, - const char __user *uargs) - { - struct load_info info = { NULL, }; -- struct module *mod; -+ struct module *mod, *old; - long err; - - pr_debug("load_module: umod=%p, len=%lu, uargs=%p\n", -@@ -2918,8 +2932,18 @@ static struct module *load_module(void __user *umod, - * function to insert in a way safe to concurrent readers. - * The mutex protects against concurrent writers. - */ -+again: - mutex_lock(&module_mutex); -- if (find_module(mod->name)) { -+ if ((old = find_module(mod->name)) != NULL) { -+ if (old->state == MODULE_STATE_COMING) { -+ /* Wait in case it fails to load. */ -+ mutex_unlock(&module_mutex); -+ err = wait_event_interruptible(module_wq, -+ finished_loading(mod->name)); -+ if (err) -+ goto free_arch_cleanup; -+ goto again; -+ } - err = -EEXIST; - goto unlock; - } |