On 06/27/2020 12:48 PM, Christophe Leroy wrote:

Le 15/06/2020 à 05:37, Anshuman Khandual a écrit :

quoted

This adds new tests validating for these following arch advanced page table
helpers. These tests create and test specific mapping types at various page
table levels.

1. pxxp_set_wrprotect()
2. pxxp_get_and_clear()
3. pxxp_set_access_flags()
4. pxxp_get_and_clear_full()
5. pxxp_test_and_clear_young()
6. pxx_leaf()
7. pxx_set_huge()
8. pxx_(clear|mk)_savedwrite()
9. huge_pxxp_xxx()

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Mike Rapoport <redacted>
Cc: Vineet Gupta <redacted>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <redacted>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Heiko Carstens <redacted>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <redacted>
Cc: Thomas Gleixner <redacted>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kirill A. Shutemov <redacted>
Cc: Paul Walmsley <redacted>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: linux-snps-arc@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-s390@vger.kernel.org
Cc: linux-riscv@lists.infradead.org
Cc: x86@kernel.org
Cc: linux-mm@kvack.org
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Anshuman Khandual <redacted>
---
  mm/debug_vm_pgtable.c | 306 ++++++++++++++++++++++++++++++++++++++++++
  1 file changed, 306 insertions(+)

diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index ffa163d4c63c..e3f9f8317a98 100644
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c

@@ -21,6 +21,7 @@

  #include <linux/module.h>
  #include <linux/pfn_t.h>
  #include <linux/printk.h>
+#include <linux/pgtable.h>
  #include <linux/random.h>
  #include <linux/spinlock.h>
  #include <linux/swap.h>

@@ -28,6 +29,7 @@

  #include <linux/start_kernel.h>
  #include <linux/sched/mm.h>
  #include <asm/pgalloc.h>
+#include <asm/tlbflush.h>
    #define VMFLAGS    (VM_READ|VM_WRITE|VM_EXEC)
  @@ -55,6 +57,54 @@ static void __init pte_basic_tests(unsigned long pfn, pgprot_t prot)
      WARN_ON(pte_write(pte_wrprotect(pte_mkwrite(pte))));
  }
  +static void __init pte_advanced_tests(struct mm_struct *mm,
+            struct vm_area_struct *vma, pte_t *ptep,
+            unsigned long pfn, unsigned long vaddr, pgprot_t prot)
+{
+    pte_t pte = pfn_pte(pfn, prot);
+
+    pte = pfn_pte(pfn, prot);
+    set_pte_at(mm, vaddr, ptep, pte);
+    ptep_set_wrprotect(mm, vaddr, ptep);
+    pte = READ_ONCE(*ptep);

same

quoted

+    WARN_ON(pte_write(pte));
+
+    pte = pfn_pte(pfn, prot);
+    set_pte_at(mm, vaddr, ptep, pte);
+    ptep_get_and_clear(mm, vaddr, ptep);
+    pte = READ_ONCE(*ptep);

same

quoted

+    WARN_ON(!pte_none(pte));
+
+    pte = pfn_pte(pfn, prot);
+    pte = pte_wrprotect(pte);
+    pte = pte_mkclean(pte);
+    set_pte_at(mm, vaddr, ptep, pte);
+    pte = pte_mkwrite(pte);
+    pte = pte_mkdirty(pte);
+    ptep_set_access_flags(vma, vaddr, ptep, pte, 1);
+    pte = READ_ONCE(*ptep);

same

quoted

+    WARN_ON(!(pte_write(pte) && pte_dirty(pte)));
+
+    pte = pfn_pte(pfn, prot);
+    set_pte_at(mm, vaddr, ptep, pte);
+    ptep_get_and_clear_full(mm, vaddr, ptep, 1);
+    pte = READ_ONCE(*ptep);

same

quoted

+    WARN_ON(!pte_none(pte));
+
+    pte = pte_mkyoung(pte);
+    set_pte_at(mm, vaddr, ptep, pte);
+    ptep_test_and_clear_young(vma, vaddr, ptep);
+    pte = READ_ONCE(*ptep);

same

quoted

+    WARN_ON(pte_young(pte));
+}
+
+static void __init pte_savedwrite_tests(unsigned long pfn, pgprot_t prot)
+{
+    pte_t pte = pfn_pte(pfn, prot);
+
+    WARN_ON(!pte_savedwrite(pte_mk_savedwrite(pte_clear_savedwrite(pte))));
+    WARN_ON(pte_savedwrite(pte_clear_savedwrite(pte_mk_savedwrite(pte))));
+}
  #ifdef CONFIG_TRANSPARENT_HUGEPAGE
  static void __init pmd_basic_tests(unsigned long pfn, pgprot_t prot)
  {

@@ -77,6 +127,89 @@ static void __init pmd_basic_tests(unsigned long pfn, pgprot_t prot)

      WARN_ON(!pmd_bad(pmd_mkhuge(pmd)));
  }
  +static void __init pmd_advanced_tests(struct mm_struct *mm,
+        struct vm_area_struct *vma, pmd_t *pmdp,
+        unsigned long pfn, unsigned long vaddr, pgprot_t prot)
+{
+    pmd_t pmd = pfn_pmd(pfn, prot);
+
+    if (!has_transparent_hugepage())
+        return;
+
+    /* Align the address wrt HPAGE_PMD_SIZE */
+    vaddr = (vaddr & HPAGE_PMD_MASK) + HPAGE_PMD_SIZE;
+
+    pmd = pfn_pmd(pfn, prot);
+    set_pmd_at(mm, vaddr, pmdp, pmd);
+    pmdp_set_wrprotect(mm, vaddr, pmdp);
+    pmd = READ_ONCE(*pmdp);
+    WARN_ON(pmd_write(pmd));
+
+    pmd = pfn_pmd(pfn, prot);
+    set_pmd_at(mm, vaddr, pmdp, pmd);
+    pmdp_huge_get_and_clear(mm, vaddr, pmdp);
+    pmd = READ_ONCE(*pmdp);
+    WARN_ON(!pmd_none(pmd));
+
+    pmd = pfn_pmd(pfn, prot);
+    pmd = pmd_wrprotect(pmd);
+    pmd = pmd_mkclean(pmd);
+    set_pmd_at(mm, vaddr, pmdp, pmd);
+    pmd = pmd_mkwrite(pmd);
+    pmd = pmd_mkdirty(pmd);
+    pmdp_set_access_flags(vma, vaddr, pmdp, pmd, 1);
+    pmd = READ_ONCE(*pmdp);
+    WARN_ON(!(pmd_write(pmd) && pmd_dirty(pmd)));
+
+    pmd = pmd_mkhuge(pfn_pmd(pfn, prot));
+    set_pmd_at(mm, vaddr, pmdp, pmd);
+    pmdp_huge_get_and_clear_full(vma, vaddr, pmdp, 1);
+    pmd = READ_ONCE(*pmdp);
+    WARN_ON(!pmd_none(pmd));
+
+    pmd = pmd_mkyoung(pmd);
+    set_pmd_at(mm, vaddr, pmdp, pmd);
+    pmdp_test_and_clear_young(vma, vaddr, pmdp);
+    pmd = READ_ONCE(*pmdp);
+    WARN_ON(pmd_young(pmd));
+}
+
+static void __init pmd_leaf_tests(unsigned long pfn, pgprot_t prot)
+{
+    pmd_t pmd = pfn_pmd(pfn, prot);
+
+    /*
+     * PMD based THP is a leaf entry.
+     */
+    pmd = pmd_mkhuge(pmd);
+    WARN_ON(!pmd_leaf(pmd));
+}
+
+static void __init pmd_huge_tests(pmd_t *pmdp, unsigned long pfn, pgprot_t prot)
+{
+    pmd_t pmd;
+
+    if (!IS_ENABLED(CONFIG_HAVE_ARCH_HUGE_VMAP))
+        return;
+    /*
+     * X86 defined pmd_set_huge() verifies that the given
+     * PMD is not a populated non-leaf entry.
+     */
+    WRITE_ONCE(*pmdp, __pmd(0));
+    WARN_ON(!pmd_set_huge(pmdp, __pfn_to_phys(pfn), prot));
+    WARN_ON(!pmd_clear_huge(pmdp));
+    pmd = READ_ONCE(*pmdp);
+    WARN_ON(!pmd_none(pmd));
+}
+
+static void __init pmd_savedwrite_tests(unsigned long pfn, pgprot_t prot)
+{
+    pmd_t pmd = pfn_pmd(pfn, prot);
+
+    WARN_ON(!pmd_savedwrite(pmd_mk_savedwrite(pmd_clear_savedwrite(pmd))));
+    WARN_ON(pmd_savedwrite(pmd_clear_savedwrite(pmd_mk_savedwrite(pmd))));
+}
+
  #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
  static void __init pud_basic_tests(unsigned long pfn, pgprot_t prot)
  {

@@ -100,12 +233,115 @@ static void __init pud_basic_tests(unsigned long pfn, pgprot_t prot)

       */
      WARN_ON(!pud_bad(pud_mkhuge(pud)));
  }
+
+static void pud_advanced_tests(struct mm_struct *mm,
+        struct vm_area_struct *vma, pud_t *pudp,
+        unsigned long pfn, unsigned long vaddr, pgprot_t prot)
+{
+    pud_t pud = pfn_pud(pfn, prot);
+
+    if (!has_transparent_hugepage())
+        return;
+
+    /* Align the address wrt HPAGE_PUD_SIZE */
+    vaddr = (vaddr & HPAGE_PUD_MASK) + HPAGE_PUD_SIZE;
+
+    set_pud_at(mm, vaddr, pudp, pud);
+    pudp_set_wrprotect(mm, vaddr, pudp);
+    pud = READ_ONCE(*pudp);
+    WARN_ON(pud_write(pud));
+
+#ifndef __PAGETABLE_PMD_FOLDED
+    pud = pfn_pud(pfn, prot);
+    set_pud_at(mm, vaddr, pudp, pud);
+    pudp_huge_get_and_clear(mm, vaddr, pudp);
+    pud = READ_ONCE(*pudp);
+    WARN_ON(!pud_none(pud));
+
+    pud = pfn_pud(pfn, prot);
+    set_pud_at(mm, vaddr, pudp, pud);
+    pudp_huge_get_and_clear_full(mm, vaddr, pudp, 1);
+    pud = READ_ONCE(*pudp);
+    WARN_ON(!pud_none(pud));
+#endif /* __PAGETABLE_PMD_FOLDED */
+    pud = pfn_pud(pfn, prot);
+    pud = pud_wrprotect(pud);
+    pud = pud_mkclean(pud);
+    set_pud_at(mm, vaddr, pudp, pud);
+    pud = pud_mkwrite(pud);
+    pud = pud_mkdirty(pud);
+    pudp_set_access_flags(vma, vaddr, pudp, pud, 1);
+    pud = READ_ONCE(*pudp);
+    WARN_ON(!(pud_write(pud) && pud_dirty(pud)));
+
+    pud = pud_mkyoung(pud);
+    set_pud_at(mm, vaddr, pudp, pud);
+    pudp_test_and_clear_young(vma, vaddr, pudp);
+    pud = READ_ONCE(*pudp);
+    WARN_ON(pud_young(pud));
+}
+
+static void __init pud_leaf_tests(unsigned long pfn, pgprot_t prot)
+{
+    pud_t pud = pfn_pud(pfn, prot);
+
+    /*
+     * PUD based THP is a leaf entry.
+     */
+    pud = pud_mkhuge(pud);
+    WARN_ON(!pud_leaf(pud));
+}
+
+static void __init pud_huge_tests(pud_t *pudp, unsigned long pfn, pgprot_t prot)
+{
+    pud_t pud;
+
+    if (!IS_ENABLED(CONFIG_HAVE_ARCH_HUGE_VMAP))
+        return;
+    /*
+     * X86 defined pud_set_huge() verifies that the given
+     * PUD is not a populated non-leaf entry.
+     */
+    WRITE_ONCE(*pudp, __pud(0));
+    WARN_ON(!pud_set_huge(pudp, __pfn_to_phys(pfn), prot));
+    WARN_ON(!pud_clear_huge(pudp));
+    pud = READ_ONCE(*pudp);
+    WARN_ON(!pud_none(pud));
+}
  #else  /* !CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */
  static void __init pud_basic_tests(unsigned long pfn, pgprot_t prot) { }
+static void pud_advanced_tests(struct mm_struct *mm,
+        struct vm_area_struct *vma, pud_t *pudp,
+        unsigned long pfn, unsigned long vaddr, pgprot_t prot)
+{
+}
+static void __init pud_leaf_tests(unsigned long pfn, pgprot_t prot) { }
+static void __init pud_huge_tests(pud_t *pudp, unsigned long pfn, pgprot_t prot)
+{
+}
  #endif /* CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */
  #else  /* !CONFIG_TRANSPARENT_HUGEPAGE */
  static void __init pmd_basic_tests(unsigned long pfn, pgprot_t prot) { }
  static void __init pud_basic_tests(unsigned long pfn, pgprot_t prot) { }
+static void __init pmd_advanced_tests(struct mm_struct *mm,
+        struct vm_area_struct *vma, pmd_t *pmdp,
+        unsigned long pfn, unsigned long vaddr, pgprot_t prot)
+{
+}
+static void __init pud_advanced_tests(struct mm_struct *mm,
+        struct vm_area_struct *vma, pud_t *pudp,
+        unsigned long pfn, unsigned long vaddr, pgprot_t prot)
+{
+}
+static void __init pmd_leaf_tests(unsigned long pfn, pgprot_t prot) { }
+static void __init pud_leaf_tests(unsigned long pfn, pgprot_t prot) { }
+static void __init pmd_huge_tests(pmd_t *pmdp, unsigned long pfn, pgprot_t prot)
+{
+}
+static void __init pud_huge_tests(pud_t *pudp, unsigned long pfn, pgprot_t prot)
+{
+}
+static void __init pmd_savedwrite_tests(unsigned long pfn, pgprot_t prot) { }
  #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
    static void __init p4d_basic_tests(unsigned long pfn, pgprot_t prot)

@@ -495,8 +731,56 @@ static void __init hugetlb_basic_tests(unsigned long pfn, pgprot_t prot)

      WARN_ON(!pte_huge(pte_mkhuge(pte)));
  #endif /* CONFIG_ARCH_WANT_GENERAL_HUGETLB */
  }
+
+static void __init hugetlb_advanced_tests(struct mm_struct *mm,
+                      struct vm_area_struct *vma,
+                      pte_t *ptep, unsigned long pfn,
+                      unsigned long vaddr, pgprot_t prot)
+{
+    struct page *page = pfn_to_page(pfn);
+    pte_t pte = READ_ONCE(*ptep);

Remplace with ptep_get() to avoid build failure on powerpc 8xx.

Sure, will replace all open PTE pointer accesses with ptep_get().