[PATCH] flush icache in correct context

flush_icache_range() is used in two different situation - in binfmt_elf.c &
co for user space mappings and module.c for kernel modules.  On m68k
flush_icache_range() doesn't know which data to flush, as it has separate
address spaces and the pointer argument can be valid in either address
space.

First I considered splitting flush_icache_range(), but this patch is
simpler.  Setting the correct context gives flush_icache_range() enough
information to flush the correct data.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/kernel/module.c b/kernel/module.c
index 5734ab09d3f984af2e424a5b3da5fbf79f83aef2..83b3d376708c04f00fdf674622b1c1071045eada 100644 (file)
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -1758,6 +1758,7 @@ 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 */
@@ -1775,6 +1776,9 @@ 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,
@@ -1783,6 +1787,8 @@ sys_init_module(void __user *umod,
        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);