Commit 44966c44 authored by Gavin Shan's avatar Gavin Shan Committed by Linus Torvalds
Browse files

mm/debug_vm_pgtable: use struct pgtable_debug_args in PTE modifying tests 

This uses struct pgtable_debug_args in PTE modifying tests.  The allocated
page is used as set_pte_at() is used there.  The tests are skipped if the
allocated page doesn't exist.  It's notable that args->ptep need to be
mapped before the tests.  The reason why we don't map args->ptep at the
beginning is PTE entry is only mapped and accessible in atomic context
when CONFIG_HIGHPTE is enabled.  So we avoid to do that so that atomic
context is only enabled if needed.

Besides, the unused variable @pte_aligned and @ptep in debug_vm_pgtable()
are dropped.

Link: https://lkml.kernel.org/r/20210809092631.1888748-8-gshan@redhat.com


Signed-off-by: default avatarGavin Shan <gshan@redhat.com>
Reviewed-by: default avatarAnshuman Khandual <anshuman.khandual@arm.com>
Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu>	[powerpc 8xx]
Tested-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>	[s390]
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chunyu Hu <chuhu@redhat.com>
Cc: Qian Cai <cai@lca.pw>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 4878a888

mm/debug_vm_pgtable.c

+32 −35
Original line number Diff line number Diff line
@@ -117,10 +117,7 @@ static void __init pte_basic_tests(struct pgtable_debug_args *args, int idx) 
	WARN_ON(!pte_dirty(pte_wrprotect(pte_mkdirty(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)

static void __init pte_advanced_tests(struct pgtable_debug_args *args)

{

	pte_t pte;
@@ -129,35 +126,37 @@ static void __init pte_advanced_tests(struct mm_struct *mm, 
	 * This requires set_pte_at to be not used to update an

	 * existing pte entry. Clear pte before we do set_pte_at

	 */

	if (args->pte_pfn == ULONG_MAX)

		return;



	pr_debug("Validating PTE advanced\n");

	pte = pfn_pte(pfn, prot);

	set_pte_at(mm, vaddr, ptep, pte);

	ptep_set_wrprotect(mm, vaddr, ptep);

	pte = ptep_get(ptep);

	pte = pfn_pte(args->pte_pfn, args->page_prot);

	set_pte_at(args->mm, args->vaddr, args->ptep, pte);

	ptep_set_wrprotect(args->mm, args->vaddr, args->ptep);

	pte = ptep_get(args->ptep);

	WARN_ON(pte_write(pte));

	ptep_get_and_clear(mm, vaddr, ptep);

	pte = ptep_get(ptep);

	ptep_get_and_clear(args->mm, args->vaddr, args->ptep);

	pte = ptep_get(args->ptep);

	WARN_ON(!pte_none(pte));



	pte = pfn_pte(pfn, prot);

	pte = pfn_pte(args->pte_pfn, args->page_prot);

	pte = pte_wrprotect(pte);

	pte = pte_mkclean(pte);

	set_pte_at(mm, vaddr, ptep, pte);

	set_pte_at(args->mm, args->vaddr, args->ptep, pte);

	pte = pte_mkwrite(pte);

	pte = pte_mkdirty(pte);

	ptep_set_access_flags(vma, vaddr, ptep, pte, 1);

	pte = ptep_get(ptep);

	ptep_set_access_flags(args->vma, args->vaddr, args->ptep, pte, 1);

	pte = ptep_get(args->ptep);

	WARN_ON(!(pte_write(pte) && pte_dirty(pte)));

	ptep_get_and_clear_full(mm, vaddr, ptep, 1);

	pte = ptep_get(ptep);

	ptep_get_and_clear_full(args->mm, args->vaddr, args->ptep, 1);

	pte = ptep_get(args->ptep);

	WARN_ON(!pte_none(pte));



	pte = pfn_pte(pfn, prot);

	pte = pfn_pte(args->pte_pfn, args->page_prot);

	pte = pte_mkyoung(pte);

	set_pte_at(mm, vaddr, ptep, pte);

	ptep_test_and_clear_young(vma, vaddr, ptep);

	pte = ptep_get(ptep);

	set_pte_at(args->mm, args->vaddr, args->ptep, pte);

	ptep_test_and_clear_young(args->vma, args->vaddr, args->ptep);

	pte = ptep_get(args->ptep);

	WARN_ON(pte_young(pte));

}
@@ -618,20 +617,21 @@ static void __init pgd_populate_tests(struct mm_struct *mm, pgd_t *pgdp, 
}

#endif /* PAGETABLE_P4D_FOLDED */



static void __init pte_clear_tests(struct mm_struct *mm, pte_t *ptep,

				   unsigned long pfn, unsigned long vaddr,

				   pgprot_t prot)

static void __init pte_clear_tests(struct pgtable_debug_args *args)

{

	pte_t pte = pfn_pte(pfn, prot);

	pte_t pte = pfn_pte(args->pte_pfn, args->page_prot);



	if (args->pte_pfn == ULONG_MAX)

		return;



	pr_debug("Validating PTE clear\n");

#ifndef CONFIG_RISCV

	pte = __pte(pte_val(pte) | RANDOM_ORVALUE);

#endif

	set_pte_at(mm, vaddr, ptep, pte);

	set_pte_at(args->mm, args->vaddr, args->ptep, pte);

	barrier();

	pte_clear(mm, vaddr, ptep);

	pte = ptep_get(ptep);

	pte_clear(args->mm, args->vaddr, args->ptep);

	pte = ptep_get(args->ptep);

	WARN_ON(!pte_none(pte));

}
@@ -1221,11 +1221,10 @@ static int __init debug_vm_pgtable(void) 
	p4d_t *p4dp, *saved_p4dp;

	pud_t *pudp, *saved_pudp;

	pmd_t *pmdp, *saved_pmdp, pmd;

	pte_t *ptep;

	pgtable_t saved_ptep;

	pgprot_t prot;

	phys_addr_t paddr;

	unsigned long vaddr, pte_aligned, pmd_aligned;

	unsigned long vaddr, pmd_aligned;

	unsigned long pud_aligned;

	spinlock_t *ptl = NULL;

	int idx, ret;
@@ -1260,10 +1259,8 @@ static int __init debug_vm_pgtable(void) 
	 */

	paddr = __pa_symbol(&start_kernel);



	pte_aligned = (paddr & PAGE_MASK) >> PAGE_SHIFT;

	pmd_aligned = (paddr & PMD_MASK) >> PAGE_SHIFT;

	pud_aligned = (paddr & PUD_MASK) >> PAGE_SHIFT;

	WARN_ON(!pfn_valid(pte_aligned));



	pgdp = pgd_offset(mm, vaddr);

	p4dp = p4d_alloc(mm, pgdp, vaddr);
@@ -1345,10 +1342,10 @@ static int __init debug_vm_pgtable(void) 
	 * proper page table lock.

	 */



	ptep = pte_offset_map_lock(mm, pmdp, vaddr, &ptl);

	pte_clear_tests(mm, ptep, pte_aligned, vaddr, prot);

	pte_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot);

	pte_unmap_unlock(ptep, ptl);

	args.ptep = pte_offset_map_lock(args.mm, args.pmdp, args.vaddr, &ptl);

	pte_clear_tests(&args);

	pte_advanced_tests(&args);

	pte_unmap_unlock(args.ptep, ptl);



	ptl = pmd_lock(mm, pmdp);

	pmd_clear_tests(mm, pmdp);