On Wed, Oct 03, 2018 at 11:22:55PM +0200, Borislav Petkov wrote: > On Fri, Sep 28, 2018 at 04:55:19PM +0200, Thomas Gleixner wrote: > > Sorry for the delay and thanks for the data. A quick diff did not reveal > > anything obvious. I'll have a closer look and we probably need more (other) > > information to nail that down. I also triggered this when working in the PTI-x32 code. It always happens on a 32-bit PAE kernel for me. Tracking it down I ended up in (iirc) arch/x86/mm/pageattr.c function static_protections(): /* * The BIOS area between 640k and 1Mb needs to be executable for * PCI BIOS based config access (CONFIG_PCI_GOBIOS) support. */ #ifdef CONFIG_PCI_BIOS if (pcibios_enabled && within(pfn, BIOS_BEGIN >> PAGE_SHIFT, BIOS_END >> PAGE_SHIFT)) pgprot_val(forbidden) |= _PAGE_NX; #endif I think that is the reason we are seeing this in that configuration. Regards, Joerg
