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From: Anshuman Khandual <anshuman.khandual@arm.com>
To: linux-mm@kvack.org
Cc: christophe.leroy@c-s.fr,
	Anshuman Khandual <anshuman.khandual@arm.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Mike Rapoport <rppt@linux.ibm.com>,
	Vineet Gupta <vgupta@synopsys.com>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will@kernel.org>,
	Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	Paul Mackerras <paulus@samba.org>,
	Michael Ellerman <mpe@ellerman.id.au>,
	Heiko Carstens <heiko.carstens@de.ibm.com>,
	Vasily Gorbik <gor@linux.ibm.com>,
	Christian Borntraeger <borntraeger@de.ibm.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	"H. Peter Anvin" <hpa@zytor.com>,
	"Kirill A . Shutemov" <kirill@shutemov.name>,
	Paul Walmsley <paul.walmsley@sifive.com>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	linux-snps-arc@lists.infradead.org,
	linux-arm-kernel@lists.infradead.org,
	linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org,
	linux-riscv@lists.infradead.org, x86@kernel.org,
	linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH V2 2/3] mm/debug: Add tests validating arch advanced page table helpers
Date: Tue, 24 Mar 2020 10:52:54 +0530	[thread overview]
Message-ID: <1585027375-9997-3-git-send-email-anshuman.khandual@arm.com> (raw)
In-Reply-To: <1585027375-9997-1-git-send-email-anshuman.khandual@arm.com>

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 <rppt@linux.ibm.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
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-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
---
 mm/debug_vm_pgtable.c | 290 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 290 insertions(+)

diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index 15055a8f6478..87b4b495333b 100644
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c
@@ -29,6 +29,7 @@
 #include <linux/sched/mm.h>
 #include <asm/pgalloc.h>
 #include <asm/pgtable.h>
+#include <asm/tlbflush.h>
 
 /*
  * Basic operations
@@ -68,6 +69,54 @@ 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);
+	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);
+	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);
+	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);
+	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);
+	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)
 {
@@ -87,6 +136,83 @@ 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);
+
+	/* 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(mm, 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;
+
+	/*
+	 * 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)
 {
@@ -107,12 +233,110 @@ 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);
+
+	/* 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
+	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;
+
+	/*
+	 * 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
 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
 #else
 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
 
 static void __init p4d_basic_tests(unsigned long pfn, pgprot_t prot)
@@ -500,8 +724,52 @@ static void __init hugetlb_basic_tests(unsigned long pfn, pgprot_t prot)
 	WARN_ON(!pte_huge(pte_mkhuge(pte)));
 #endif
 }
+
+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);
+
+	pte = __pte(pte_val(pte) | RANDOM_ORVALUE);
+	set_huge_pte_at(mm, vaddr, ptep, pte);
+	barrier();
+	WARN_ON(!pte_same(pte, huge_ptep_get(ptep)));
+	huge_pte_clear(mm, vaddr, ptep, PMD_SIZE);
+	pte = READ_ONCE(*ptep);
+	WARN_ON(!huge_pte_none(pte));
+
+	pte = mk_huge_pte(page, prot);
+	set_huge_pte_at(mm, vaddr, ptep, pte);
+	huge_ptep_set_wrprotect(mm, vaddr, ptep);
+	pte = READ_ONCE(*ptep);
+	WARN_ON(huge_pte_write(pte));
+
+	pte = mk_huge_pte(page, prot);
+	set_huge_pte_at(mm, vaddr, ptep, pte);
+	huge_ptep_get_and_clear(mm, vaddr, ptep);
+	pte = READ_ONCE(*ptep);
+	WARN_ON(!huge_pte_none(pte));
+
+	pte = mk_huge_pte(page, prot);
+	pte = huge_pte_wrprotect(pte);
+	set_huge_pte_at(mm, vaddr, ptep, pte);
+	pte = huge_pte_mkwrite(pte);
+	pte = huge_pte_mkdirty(pte);
+	huge_ptep_set_access_flags(vma, vaddr, ptep, pte, 1);
+	pte = READ_ONCE(*ptep);
+	WARN_ON(!(huge_pte_write(pte) && huge_pte_dirty(pte)));
+}
 #else
 static void __init hugetlb_basic_tests(unsigned long pfn, pgprot_t prot) { }
+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)
+{
+}
 #endif
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
@@ -564,6 +832,7 @@ static unsigned long __init get_random_vaddr(void)
 
 void __init debug_vm_pgtable(void)
 {
+	struct vm_area_struct *vma;
 	struct mm_struct *mm;
 	pgd_t *pgdp;
 	p4d_t *p4dp, *saved_p4dp;
@@ -592,6 +861,12 @@ void __init debug_vm_pgtable(void)
 	 */
 	protnone = __P000;
 
+	vma = vm_area_alloc(mm);
+	if (!vma) {
+		pr_err("vma allocation failed\n");
+		return;
+	}
+
 	/*
 	 * PFN for mapping at PTE level is determined from a standard kernel
 	 * text symbol. But pfns for higher page table levels are derived by
@@ -640,6 +915,20 @@ void __init debug_vm_pgtable(void)
 	p4d_clear_tests(mm, p4dp);
 	pgd_clear_tests(mm, pgdp);
 
+	pte_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot);
+	pmd_advanced_tests(mm, vma, pmdp, pmd_aligned, vaddr, prot);
+	pud_advanced_tests(mm, vma, pudp, pud_aligned, vaddr, prot);
+	hugetlb_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot);
+
+	pmd_leaf_tests(pmd_aligned, prot);
+	pud_leaf_tests(pud_aligned, prot);
+
+	pmd_huge_tests(pmdp, pmd_aligned, prot);
+	pud_huge_tests(pudp, pud_aligned, prot);
+
+	pte_savedwrite_tests(pte_aligned, prot);
+	pmd_savedwrite_tests(pmd_aligned, prot);
+
 	pte_unmap_unlock(ptep, ptl);
 
 	pmd_populate_tests(mm, pmdp, saved_ptep);
@@ -674,6 +963,7 @@ void __init debug_vm_pgtable(void)
 	pmd_free(mm, saved_pmdp);
 	pte_free(mm, saved_ptep);
 
+	vm_area_free(vma);
 	mm_dec_nr_puds(mm);
 	mm_dec_nr_pmds(mm);
 	mm_dec_nr_ptes(mm);
-- 
2.20.1



  parent reply	other threads:[~2020-03-24  5:23 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-24  5:22 [PATCH V2 0/3] mm/debug: Add more arch page table helper tests Anshuman Khandual
2020-03-24  5:22 ` [PATCH V2 1/3] mm/debug: Add tests validating arch page table helpers for core features Anshuman Khandual
2020-03-24 13:29   ` Zi Yan
2020-03-26  2:18     ` Anshuman Khandual
2020-03-26 17:08       ` Zi Yan
2020-03-30  8:56   ` [mm/debug] f675f2f91d: WARNING:at_mm/debug_vm_pgtable.c:#debug_vm_pgtable kernel test robot
2020-04-05 14:49     ` Anshuman Khandual
2020-03-24  5:22 ` Anshuman Khandual [this message]
2020-03-27  7:41   ` [mm/debug] d157503f6f: WARNING:at_mm/debug_vm_pgtable.c:#debug_vm_pgtable kernel test robot
2020-03-24  5:22 ` [PATCH V2 3/3] Documentation/mm: Add descriptions for arch page table helpers Anshuman Khandual
2020-03-26  2:23 ` [PATCH V2 0/3] mm/debug: Add more arch page table helper tests Anshuman Khandual
2020-03-26 15:23   ` Christophe Leroy
2020-03-27  6:46     ` Anshuman Khandual
2020-03-27  7:00       ` Christophe Leroy
2020-03-29 14:21         ` Anshuman Khandual
2020-03-31 12:30 ` Gerald Schaefer
2020-04-05 12:28   ` Anshuman Khandual
2020-04-07 15:54     ` Gerald Schaefer
2020-04-08  7:11       ` Anshuman Khandual
2020-04-08 12:15         ` Gerald Schaefer
2020-04-09  1:06           ` Anshuman Khandual

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