Re: a13c600e15 ("x86/mm/pti: Move user W+X check into .."): WARNING: CPU: 0 PID: 1 at arch/x86/mm/dump_pagetables.c:283 note_page

From: Joerg Roedel
Date: Fri Aug 10 2018 - 04:35:09 EST


On Fri, Aug 10, 2018 at 06:33:42AM +0800, kernel test robot wrote:
> commit a13c600e15de44ccf03df28d3311ef3cb754ed9b
> Author: Joerg Roedel <jroedel@xxxxxxx>
> AuthorDate: Wed Aug 8 13:16:40 2018 +0200
> Commit: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> CommitDate: Thu Aug 9 20:42:07 2018 +0200
>
> x86/mm/pti: Move user W+X check into pti_finalize()

Okay, I found the problem and the diff below fixes it.

Ingo, Thomas, can you fold that diff into above commit or do you prefer
a separate patch?

Thanks and sorry for the hassle,


Joerg

diff --git a/arch/x86/mm/pti.c b/arch/x86/mm/pti.c
index 026a89aa16d7..d1435c78ae4f 100644
--- a/arch/x86/mm/pti.c
+++ b/arch/x86/mm/pti.c
@@ -629,5 +629,6 @@ void pti_finalize(void)
pti_clone_entry_text();
pti_clone_kernel_text();

- debug_checkwx_user();
+ if (__supported_pte_mask & _PAGE_NX)
+ debug_checkwx_user();
}