Re: -tip tree resume fail, bisect to 5bd5a45(x86: Add NX protection for kernel data)

[Peter Zijlstra <peterz@infradead.org>]

On Mon, 2010-11-22 at 15:23 +0800, Lin Ming wrote:
> Hi, all
> 
> Current -tip tree(92c883a) fail to resume after suspend to mem.
> Bisect to commit 5bd5a45(x86: Add NX protection for kernel data).

Drad, if only I'd looked at LKML before I did the bisection myself..

> commit 5bd5a452662bc37c54fb6828db1a3faf87e6511c
> Author: Matthieu Castet <castet.matthieu@free.fr>
> Date:   Tue Nov 16 22:31:26 2010 +0100
> 
>     x86: Add NX protection for kernel data
> 
> 
> I did some debug and found the regression is caused by below line.
> 
> -       set_memory_nx(rodata_start, (end - rodata_start) >> PAGE_SHIFT);
> +       set_memory_nx(rodata_start, (kernel_end - rodata_start) >> PAGE_SHIFT);


Confirmed, with that hunk reverted my machine works again..

---
 arch/x86/mm/init_64.c |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index ce59c05..71a5929 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -788,7 +788,6 @@ void mark_rodata_ro(void)
 	unsigned long rodata_start =
 		((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK;
 	unsigned long end = (unsigned long) &__end_rodata_hpage_align;
-	unsigned long kernel_end = (((unsigned long)&__init_end + HPAGE_SIZE) & HPAGE_MASK);
 	unsigned long text_end = PAGE_ALIGN((unsigned long) &__stop___ex_table);
 	unsigned long rodata_end = PAGE_ALIGN((unsigned long) &__end_rodata);
 	unsigned long data_start = (unsigned long) &_sdata;
@@ -803,7 +802,7 @@ void mark_rodata_ro(void)
 	 * The rodata section (but not the kernel text!) should also be
 	 * not-executable.
 	 */
-	set_memory_nx(rodata_start, (kernel_end - rodata_start) >> PAGE_SHIFT);
+	set_memory_nx(rodata_start, (end - rodata_start) >> PAGE_SHIFT);
 
 	rodata_test();