diff options
| author | Arjan van de Ven <arjan@infradead.org> | 2006-01-06 00:12:02 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-01-06 08:33:36 -0800 |
| commit | 63aaf3086baea7b94c218053af8237f9dbac5d05 (patch) | |
| tree | dc32bf8878d01a25a321eb6412f27bce7ec7c5b7 /arch/i386/mm/init.c | |
| parent | 37b73c828185731f6236a6387c02d7b08c150810 (diff) | |
[PATCH] x86/x86_64: mark rodata section read only: x86 parts
x86 specific parts to make the .rodata section read only
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch/i386/mm/init.c')
| -rw-r--r-- | arch/i386/mm/init.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/arch/i386/mm/init.c b/arch/i386/mm/init.c index 06e26f006238..7df494b51a5b 100644 --- a/arch/i386/mm/init.c +++ b/arch/i386/mm/init.c @@ -735,6 +735,30 @@ void free_initmem(void) printk (KERN_INFO "Freeing unused kernel memory: %dk freed\n", (__init_end - __init_begin) >> 10); } +#ifdef CONFIG_DEBUG_RODATA + +extern char __start_rodata, __end_rodata; +void mark_rodata_ro(void) +{ + unsigned long addr = (unsigned long)&__start_rodata; + + for (; addr < (unsigned long)&__end_rodata; addr += PAGE_SIZE) + change_page_attr(virt_to_page(addr), 1, PAGE_KERNEL_RO); + + printk ("Write protecting the kernel read-only data: %luk\n", + (unsigned long)(&__end_rodata - &__start_rodata) >> 10); + + /* + * change_page_attr() requires a global_flush_tlb() call after it. + * We do this after the printk so that if something went wrong in the + * change, the printk gets out at least to give a better debug hint + * of who is the culprit. + */ + global_flush_tlb(); +} +#endif + + #ifdef CONFIG_BLK_DEV_INITRD void free_initrd_mem(unsigned long start, unsigned long end) { |