• Linus Torvalds's avatar
    Merge branch 'x86-smap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 15385dfe
    Linus Torvalds authored
    Pull x86/smap support from Ingo Molnar:
     "This adds support for the SMAP (Supervisor Mode Access Prevention) CPU
      feature on Intel CPUs: a hardware feature that prevents unintended
      user-space data access from kernel privileged code.
    
      It's turned on automatically when possible.
    
      This, in combination with SMEP, makes it even harder to exploit kernel
      bugs such as NULL pointer dereferences."
    
    Fix up trivial conflict in arch/x86/kernel/entry_64.S due to newly added
    includes right next to each other.
    
    * 'x86-smap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
      x86, smep, smap: Make the switching functions one-way
      x86, suspend: On wakeup always initialize cr4 and EFER
      x86-32: Start out eflags and cr4 clean
      x86, smap: Do not abuse the [f][x]rstor_checking() functions for user space
      x86-32, smap: Add STAC/CLAC instructions to 32-bit kernel entry
      x86, smap: Reduce the SMAP overhead for signal handling
      x86, smap: A page fault due to SMAP is an oops
      x86, smap: Turn on Supervisor Mode Access Prevention
      x86, smap: Add STAC and CLAC instructions to control user space access
      x86, uaccess: Merge prototypes for clear_user/__clear_user
      x86, smap: Add a header file with macros for STAC/CLAC
      x86, alternative: Add header guards to <asm/alternative-asm.h>
      x86, alternative: Use .pushsection/.popsection
      x86, smap: Add CR4 bit for SMAP
      x86-32, mm: The WP test should be done on a kernel page
    15385dfe
alternative.h 8.29 KB