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 - 03:30:20 EST


On Fri, Aug 10, 2018 at 06:33:42AM +0800, kernel test robot wrote:
> [ 9.635329] x86/mm: Checking user space page tables
> [ 9.636271] ------------[ cut here ]------------
> [ 9.637045] x86/mm: Found insecure W+X mapping at address (ptrval)/0xffc01000
> [ 9.638228] WARNING: CPU: 0 PID: 1 at arch/x86/mm/dump_pagetables.c:283 note_page+0x66b/0x870

Hmm, weird, this warning triggers for 32-bit non-pae. There is no
NX-bit in this mode, so the check shouldn't happen there. I'll
investigate.


Joerg