From 378bac820be6a0ec95df8151524de73ad2b2d2ac Mon Sep 17 00:00:00 2001 From: Thomas Koeller Date: Tue, 6 Sep 2005 15:17:11 -0700 Subject: [PATCH] flush icache early when loading module Change the sequence of operations performed during module loading to flush the instruction cache before module parameters are processed. If a module has parameters of an unusual type that cannot be handled using the standard accessor functions param_set_xxx and param_get_xxx, it has to to provide a set of accessor functions for this type. This requires module code to be executed during parameter processing, which is of course only possible after the icache has been flushed. Signed-off-by: Thomas Koeller Cc: Rusty Russell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/module.c | 33 +++++++++++++++++++-------------- 1 file changed, 19 insertions(+), 14 deletions(-) (limited to 'kernel') diff --git a/kernel/module.c b/kernel/module.c index c32995fbd8fd..4b39d3793c72 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1509,6 +1509,7 @@ static struct module *load_module(void __user *umod, long err = 0; void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */ struct exception_table_entry *extable; + mm_segment_t old_fs; DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n", umod, len, uargs); @@ -1779,6 +1780,24 @@ static struct module *load_module(void __user *umod, if (err < 0) goto cleanup; + /* flush the icache in correct context */ + old_fs = get_fs(); + set_fs(KERNEL_DS); + + /* + * Flush the instruction cache, since we've played with text. + * Do it before processing of module parameters, so the module + * can provide parameter accessor functions of its own. + */ + if (mod->module_init) + flush_icache_range((unsigned long)mod->module_init, + (unsigned long)mod->module_init + + mod->init_size); + flush_icache_range((unsigned long)mod->module_core, + (unsigned long)mod->module_core + mod->core_size); + + set_fs(old_fs); + mod->args = args; if (obsparmindex) { err = obsolete_params(mod->name, mod->args, @@ -1860,7 +1879,6 @@ sys_init_module(void __user *umod, const char __user *uargs) { struct module *mod; - mm_segment_t old_fs = get_fs(); int ret = 0; /* Must have permission */ @@ -1878,19 +1896,6 @@ sys_init_module(void __user *umod, return PTR_ERR(mod); } - /* flush the icache in correct context */ - set_fs(KERNEL_DS); - - /* Flush the instruction cache, since we've played with text */ - if (mod->module_init) - flush_icache_range((unsigned long)mod->module_init, - (unsigned long)mod->module_init - + mod->init_size); - flush_icache_range((unsigned long)mod->module_core, - (unsigned long)mod->module_core + mod->core_size); - - set_fs(old_fs); - /* Now sew it into the lists. They won't access us, since strong_try_module_get() will fail. */ stop_machine_run(__link_module, mod, NR_CPUS); -- cgit v1.2.3