From: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
To: linux-mm@kvack.org, akpm@linux-foundation.org
Cc: linuxppc-dev@lists.ozlabs.org,
"Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>,
Anshuman Khandual <anshuman.khandual@arm.com>
Subject: [PATCH v2 01/13] powerpc/mm: Add DEBUG_VM WARN for pmd_clear
Date: Wed, 19 Aug 2020 18:30:55 +0530 [thread overview]
Message-ID: <20200819130107.478414-2-aneesh.kumar@linux.ibm.com> (raw)
In-Reply-To: <20200819130107.478414-1-aneesh.kumar@linux.ibm.com>
With the hash page table, the kernel should not use pmd_clear for clearing
huge pte entries. Add a DEBUG_VM WARN to catch the wrong usage.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/include/asm/book3s/64/pgtable.h | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
index 6de56c3b33c4..079211968987 100644
--- a/arch/powerpc/include/asm/book3s/64/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
@@ -868,6 +868,13 @@ static inline bool pte_ci(pte_t pte)
static inline void pmd_clear(pmd_t *pmdp)
{
+ if (IS_ENABLED(CONFIG_DEBUG_VM) && !radix_enabled()) {
+ /*
+ * Don't use this if we can possibly have a hash page table
+ * entry mapping this.
+ */
+ WARN_ON((pmd_val(*pmdp) & (H_PAGE_HASHPTE | _PAGE_PTE)) == (H_PAGE_HASHPTE | _PAGE_PTE));
+ }
*pmdp = __pmd(0);
}
@@ -916,6 +923,13 @@ static inline int pmd_bad(pmd_t pmd)
static inline void pud_clear(pud_t *pudp)
{
+ if (IS_ENABLED(CONFIG_DEBUG_VM) && !radix_enabled()) {
+ /*
+ * Don't use this if we can possibly have a hash page table
+ * entry mapping this.
+ */
+ WARN_ON((pud_val(*pudp) & (H_PAGE_HASHPTE | _PAGE_PTE)) == (H_PAGE_HASHPTE | _PAGE_PTE));
+ }
*pudp = __pud(0);
}
--
2.26.2
next prev parent reply other threads:[~2020-08-19 13:06 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-19 13:00 [PATCH v2 00/13] mm/debug_vm_pgtable fixes Aneesh Kumar K.V
2020-08-19 13:00 ` Aneesh Kumar K.V [this message]
2020-08-19 13:00 ` [PATCH v2 02/13] powerpc/mm: Move setting pte specific flags to pfn_pte Aneesh Kumar K.V
2020-08-19 13:00 ` [PATCH v2 03/13] mm/debug_vm_pgtable/ppc64: Avoid setting top bits in radom value Aneesh Kumar K.V
2020-08-19 13:00 ` [PATCH v2 04/13] mm/debug_vm_pgtables/hugevmap: Use the arch helper to identify huge vmap support Aneesh Kumar K.V
2020-08-19 16:29 ` kernel test robot
2020-08-20 5:31 ` Aneesh Kumar K.V
2020-08-21 8:38 ` Anshuman Khandual
2020-08-19 13:00 ` [PATCH v2 05/13] mm/debug_vm_pgtable/savedwrite: Enable savedwrite test with CONFIG_NUMA_BALANCING Aneesh Kumar K.V
2020-08-19 13:01 ` [PATCH v2 06/13] mm/debug_vm_pgtable/THP: Mark the pte entry huge before using set_pmd/pud_at Aneesh Kumar K.V
2020-08-19 13:01 ` [PATCH v2 07/13] mm/debug_vm_pgtable/set_pte/pmd/pud: Don't use set_*_at to update an existing pte entry Aneesh Kumar K.V
2020-08-20 14:32 ` Christophe Leroy
2020-08-21 7:14 ` Aneesh Kumar K.V
2020-08-21 8:20 ` Anshuman Khandual
2020-08-19 13:01 ` [PATCH v2 08/13] mm/debug_vm_pgtable/thp: Use page table depost/withdraw with THP Aneesh Kumar K.V
2020-08-19 13:01 ` [PATCH v2 09/13] mm/debug_vm_pgtable/locks: Move non page table modifying test together Aneesh Kumar K.V
2020-08-19 13:01 ` [PATCH v2 10/13] mm/debug_vm_pgtable/locks: Take correct page table lock Aneesh Kumar K.V
2020-08-21 8:03 ` Anshuman Khandual
2020-08-21 8:08 ` Aneesh Kumar K.V
2020-08-19 13:01 ` [PATCH v2 11/13] mm/debug_vm_pgtable/pmd_clear: Don't use pmd/pud_clear on pte entries Aneesh Kumar K.V
2020-08-19 13:01 ` [PATCH v2 12/13] mm/debug_vm_pgtable/hugetlb: Disable hugetlb test on ppc64 Aneesh Kumar K.V
2020-08-19 13:01 ` [PATCH v2 13/13] mm/debug_vm_pgtable: populate a pte entry before fetching it Aneesh Kumar K.V
2020-08-19 13:45 ` [PATCH v2 00/13] mm/debug_vm_pgtable fixes Aneesh Kumar K.V
2020-08-21 3:33 ` Anshuman Khandual
2020-08-21 4:20 ` Anshuman Khandual
2020-08-21 6:53 ` Aneesh Kumar K.V
2020-08-21 8:01 ` Anshuman Khandual
2020-08-21 8:10 ` Aneesh Kumar K.V
2020-08-21 8:50 ` Aneesh Kumar K.V
2020-08-21 9:09 ` Anshuman Khandual
2020-08-21 8:51 ` Anshuman Khandual
2020-09-01 8:03 ` Christophe Leroy
2020-09-01 9:11 ` Anshuman Khandual
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