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| author | Peter Xu <peterx@redhat.com> | 2024-08-12 14:12:24 -0400 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2024-09-01 20:26:09 -0700 |
| commit | 473f24902e6a55de952e87b28450b7445a928da4 (patch) | |
| tree | d4b4beefd04c42e989216bbc5406850704eacea5 /arch/x86/mm | |
| parent | 1c399e74a97ca733d0780cc51819aa81fb292c22 (diff) | |
| download | linux-473f24902e6a55de952e87b28450b7445a928da4.tar.gz linux-473f24902e6a55de952e87b28450b7445a928da4.tar.bz2 linux-473f24902e6a55de952e87b28450b7445a928da4.zip | |
mm/x86: add missing pud helpers
Some new helpers will be needed for pud entry updates soon. Introduce
these helpers by referencing the pmd ones. Namely:
- pudp_invalidate(): this helper invalidates a huge pud before a
split happens, so that the invalidated pud entry will make sure no
race will happen (either with software, like a concurrent zap, or
hardware, like a/d bit lost).
- pud_modify(): this helper applies a new pgprot to an existing huge
pud mapping.
For more information on why we need these two helpers, please refer to the
corresponding pmd helpers in the mprotect() code path.
When at it, simplify the pud_modify()/pmd_modify() comments on shadow
stack pgtable entries to reference pte_modify() to avoid duplicating the
whole paragraph three times.
Link: https://lkml.kernel.org/r/20240812181225.1360970-7-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'arch/x86/mm')
| -rw-r--r-- | arch/x86/mm/pgtable.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c index 36e7139a61d9..5745a354a241 100644 --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -641,6 +641,18 @@ pmd_t pmdp_invalidate_ad(struct vm_area_struct *vma, unsigned long address, } #endif +#if defined(CONFIG_TRANSPARENT_HUGEPAGE) && \ + defined(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD) +pud_t pudp_invalidate(struct vm_area_struct *vma, unsigned long address, + pud_t *pudp) +{ + VM_WARN_ON_ONCE(!pud_present(*pudp)); + pud_t old = pudp_establish(vma, address, pudp, pud_mkinvalid(*pudp)); + flush_pud_tlb_range(vma, address, address + HPAGE_PUD_SIZE); + return old; +} +#endif + /** * reserve_top_address - reserves a hole in the top of kernel address space * @reserve - size of hole to reserve |