Merge tag 'x86_mm_for_v6.0_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git...

Pull x86 mm updates from Borislav Petkov:

 - Rename a PKRU macro to make more sense when reading the code

 - Update pkeys documentation

 - Avoid reading contended mm's TLB generation var if not absolutely
   necessary along with fixing a case where arch_tlbbatch_flush()
   doesn't adhere to the generation scheme and thus violates the
   conditions for the above avoidance.

* tag 'x86_mm_for_v6.0_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm/tlb: Ignore f->new_tlb_gen when zero
  x86/pkeys: Clarify PKRU_AD_KEY macro
  Documentation/protection-keys: Clean up documentation for User Space pkeys
  x86/mm/tlb: Avoid reading mm_tlb_gen when possible

diff --combined arch/x86/include/asm/tlbflush.h
index 4af5579c7ef7c6a8399469909b74223b2d94d8b2,21bf105d54f2f250ec69dc4ea4f2b3b739269dfd..cda3118f3b27d2228f6e9eeb1e7fb85a65fc0f9e
--- 1/arch/x86/include/asm/tlbflush.h
--- 2/arch/x86/include/asm/tlbflush.h
+++ b/arch/x86/include/asm/tlbflush.h
@@@ -16,6 -16,7 +16,7 @@@
  void __flush_tlb_all(void);
  
  #define TLB_FLUSH_ALL -1UL
+ #define TLB_GENERATION_INVALID        0
  
  void cr4_update_irqsoff(unsigned long set, unsigned long clear);
  unsigned long cr4_read_shadow(void);
@@@ -259,103 -260,6 +260,103 @@@ static inline void arch_tlbbatch_add_mm
  
  extern void arch_tlbbatch_flush(struct arch_tlbflush_unmap_batch *batch);
  
 +static inline bool pte_flags_need_flush(unsigned long oldflags,
 +                                      unsigned long newflags,
 +                                      bool ignore_access)
 +{
 +      /*
 +       * Flags that require a flush when cleared but not when they are set.
 +       * Only include flags that would not trigger spurious page-faults.
 +       * Non-present entries are not cached. Hardware would set the
 +       * dirty/access bit if needed without a fault.
 +       */
 +      const pteval_t flush_on_clear = _PAGE_DIRTY | _PAGE_PRESENT |
 +                                      _PAGE_ACCESSED;
 +      const pteval_t software_flags = _PAGE_SOFTW1 | _PAGE_SOFTW2 |
 +                                      _PAGE_SOFTW3 | _PAGE_SOFTW4;
 +      const pteval_t flush_on_change = _PAGE_RW | _PAGE_USER | _PAGE_PWT |
 +                        _PAGE_PCD | _PAGE_PSE | _PAGE_GLOBAL | _PAGE_PAT |
 +                        _PAGE_PAT_LARGE | _PAGE_PKEY_BIT0 | _PAGE_PKEY_BIT1 |
 +                        _PAGE_PKEY_BIT2 | _PAGE_PKEY_BIT3 | _PAGE_NX;
 +      unsigned long diff = oldflags ^ newflags;
 +
 +      BUILD_BUG_ON(flush_on_clear & software_flags);
 +      BUILD_BUG_ON(flush_on_clear & flush_on_change);
 +      BUILD_BUG_ON(flush_on_change & software_flags);
 +
 +      /* Ignore software flags */
 +      diff &= ~software_flags;
 +
 +      if (ignore_access)
 +              diff &= ~_PAGE_ACCESSED;
 +
 +      /*
 +       * Did any of the 'flush_on_clear' flags was clleared set from between
 +       * 'oldflags' and 'newflags'?
 +       */
 +      if (diff & oldflags & flush_on_clear)
 +              return true;
 +
 +      /* Flush on modified flags. */
 +      if (diff & flush_on_change)
 +              return true;
 +
 +      /* Ensure there are no flags that were left behind */
 +      if (IS_ENABLED(CONFIG_DEBUG_VM) &&
 +          (diff & ~(flush_on_clear | software_flags | flush_on_change))) {
 +              VM_WARN_ON_ONCE(1);
 +              return true;
 +      }
 +
 +      return false;
 +}
 +
 +/*
 + * pte_needs_flush() checks whether permissions were demoted and require a
 + * flush. It should only be used for userspace PTEs.
 + */
 +static inline bool pte_needs_flush(pte_t oldpte, pte_t newpte)
 +{
 +      /* !PRESENT -> * ; no need for flush */
 +      if (!(pte_flags(oldpte) & _PAGE_PRESENT))
 +              return false;
 +
 +      /* PFN changed ; needs flush */
 +      if (pte_pfn(oldpte) != pte_pfn(newpte))
 +              return true;
 +
 +      /*
 +       * check PTE flags; ignore access-bit; see comment in
 +       * ptep_clear_flush_young().
 +       */
 +      return pte_flags_need_flush(pte_flags(oldpte), pte_flags(newpte),
 +                                  true);
 +}
 +#define pte_needs_flush pte_needs_flush
 +
 +/*
 + * huge_pmd_needs_flush() checks whether permissions were demoted and require a
 + * flush. It should only be used for userspace huge PMDs.
 + */
 +static inline bool huge_pmd_needs_flush(pmd_t oldpmd, pmd_t newpmd)
 +{
 +      /* !PRESENT -> * ; no need for flush */
 +      if (!(pmd_flags(oldpmd) & _PAGE_PRESENT))
 +              return false;
 +
 +      /* PFN changed ; needs flush */
 +      if (pmd_pfn(oldpmd) != pmd_pfn(newpmd))
 +              return true;
 +
 +      /*
 +       * check PMD flags; do not ignore access-bit; see
 +       * pmdp_clear_flush_young().
 +       */
 +      return pte_flags_need_flush(pmd_flags(oldpmd), pmd_flags(newpmd),
 +                                  false);
 +}
 +#define huge_pmd_needs_flush huge_pmd_needs_flush
 +
  #endif /* !MODULE */
  
  static inline void __native_tlb_flush_global(unsigned long cr4)