From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0DF43A41 for ; Fri, 16 Jan 2026 00:25:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768523147; cv=none; b=Bp1RPBHy8q5VOYQRQNUH6mkAx1K6XS/OK0Y8yJ29a2Nrv07KVepUkVd/Ty0UAHeDFeYqTQzNYRFtzE7fd622GHj681ZQM80+0MJ0QY9kub63dHH0T2PMdO5DbDQdvBvhUpfj+V8yp2wzLt4qlDxuO4PsVw2Ikt4H7Q2l24YWmbc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768523147; c=relaxed/simple; bh=I9cxJty8RoIhNYDjthPyCwZNo0Rg3jnD/vsBbNLTgWc=; h=Date:To:From:Subject:Message-Id; b=tLlZI46VzS1N2U9aDousaHWHGLYBzbFX00m3Pq6EeRdrYW+ob3tQUb81e524SAxvSjnfsF7omZPRezNPgLmYH71GmqhLZKffV5/gqCLnuW1HdUwMEsPHSx5MRIy0xZ41JM4rn9FzxT0jwqcbDDM/8rAOzK01yuorsEr/mqO72oU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=DOY/8Ni8; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="DOY/8Ni8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CFA3FC116D0; Fri, 16 Jan 2026 00:25:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1768523146; bh=I9cxJty8RoIhNYDjthPyCwZNo0Rg3jnD/vsBbNLTgWc=; h=Date:To:From:Subject:From; b=DOY/8Ni8qYuyPCRbCbOrOqAmM5Wz/lHfg7vuKgEu8d+ZnNe+TJBWcTwDwODycIISj 0E6Wc2gCKTysreAsDIIzYW9oivr2DqL4vipp17ULGN0gVCrEVqeZljDLhEZEmiejdR BRgoWMHXZVZIeCGxaqVL4/Y9i+UFRfHSzzmBoD40= Date: Thu, 15 Jan 2026 16:25:46 -0800 To: mm-commits@vger.kernel.org,ziy@nvidia.com,zhengqi.arch@bytedance.com,willy@infradead.org,vishal.moola@gmail.com,thuth@redhat.com,sweettea-kernel@dorminy.me,ritesh.list@gmail.com,paulus@ozlabs.org,pasha.tatashin@soleen.com,npiggin@gmail.com,nicholas@linux.ibm.com,mpe@ellerman.id.au,mingo@kernel.org,maddy@linux.ibm.com,linmag7@gmail.com,kevin.brodsky@arm.com,jgg@ziepe.ca,guoweikang.kernel@gmail.com,donettom@linux.ibm.com,david@kernel.org,christophe.leroy@csgroup.eu,chleroy@kernel.org,apopple@nvidia.com,alexghiti@rivosinc.com,alex@ghiti.fr,ajd@linux.ibm.com,agordeev@linux.ibm.com,rmclure@linux.ibm.com,akpm@linux-foundation.org From: Andrew Morton Subject: + powerpc-mm-support-page-table-check.patch added to mm-new branch Message-Id: <20260116002546.CFA3FC116D0@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: powerpc/mm: support page table check has been added to the -mm mm-new branch. Its filename is powerpc-mm-support-page-table-check.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/powerpc-mm-support-page-table-check.patch This patch will later appear in the mm-new branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Note, mm-new is a provisional staging ground for work-in-progress patches, and acceptance into mm-new is a notification for others take notice and to finish up reviews. Please do not hesitate to respond to review feedback and post updated versions to replace or incrementally fixup patches in mm-new. The mm-new branch of mm.git is not included in linux-next Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via various branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there most days ------------------------------------------------------ From: Rohan McLure Subject: powerpc/mm: support page table check Date: Fri, 19 Dec 2025 04:09:44 +1100 On creation and clearing of a page table mapping, instrument such calls by invoking page_table_check_pte_set and page_table_check_pte_clear respectively. These calls serve as a sanity check against illegal mappings. Enable ARCH_SUPPORTS_PAGE_TABLE_CHECK on powerpc, except when HUGETLB_PAGE is enabled (powerpc has some weirdness in how it implements set_huge_pte_at(), which may require some further work). See also: riscv support in commit 3fee229a8eb9 ("riscv/mm: enable ARCH_SUPPORTS_PAGE_TABLE_CHECK") arm64 in commit 42b2547137f5 ("arm64/mm: enable ARCH_SUPPORTS_PAGE_TABLE_CHECK") x86_64 in commit d283d422c6c4 ("x86: mm: add x86_64 support for page table check") [ajd@linux.ibm.com: rebase, add additional instrumentation, misc fixes] Link: https://lkml.kernel.org/r/20251219-pgtable_check_v18rebase-v18-12-755bc151a50b@linux.ibm.com Reviewed-by: Christophe Leroy Signed-off-by: Rohan McLure Reviewed-by: Pasha Tatashin Signed-off-by: Andrew Donnellan Acked-by: Madhavan Srinivasan Cc: Alexander Gordeev Cc: Alexandre Ghiti Cc: Alexandre Ghiti Cc: Alistair Popple Cc: "Christophe Leroy (CS GROUP)" Cc: David Hildenbrand Cc: Donet Tom Cc: Guo Weikang Cc: Ingo Molnar Cc: Jason Gunthorpe Cc: Kevin Brodsky Cc: Magnus Lindholm Cc: "Matthew Wilcox (Oracle)" Cc: Michael Ellerman Cc: Nicholas Miehlbradt Cc: Nicholas Piggin Cc: Paul Mackerras Cc: Qi Zheng Cc: "Ritesh Harjani (IBM)" Cc: Sweet Tea Dorminy Cc: Thomas Huth Cc: "Vishal Moola (Oracle)" Cc: Zi Yan Signed-off-by: Andrew Morton --- arch/powerpc/Kconfig | 1 arch/powerpc/include/asm/book3s/32/pgtable.h | 7 ++ arch/powerpc/include/asm/book3s/64/pgtable.h | 45 +++++++++++++---- arch/powerpc/include/asm/nohash/pgtable.h | 8 ++- arch/powerpc/mm/book3s64/hash_pgtable.c | 4 + arch/powerpc/mm/book3s64/pgtable.c | 19 ++++--- arch/powerpc/mm/book3s64/radix_pgtable.c | 3 + arch/powerpc/mm/pgtable.c | 4 + 8 files changed, 73 insertions(+), 18 deletions(-) --- a/arch/powerpc/include/asm/book3s/32/pgtable.h~powerpc-mm-support-page-table-check +++ a/arch/powerpc/include/asm/book3s/32/pgtable.h @@ -202,6 +202,7 @@ void unmap_kernel_page(unsigned long va) #ifndef __ASSEMBLER__ #include #include +#include /* Bits to mask out from a PGD to get to the PUD page */ #define PGD_MASKED_BITS 0 @@ -315,7 +316,11 @@ static inline int __ptep_test_and_clear_ static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - return __pte(pte_update(mm, addr, ptep, ~_PAGE_HASHPTE, 0, 0)); + pte_t old_pte = __pte(pte_update(mm, addr, ptep, ~_PAGE_HASHPTE, 0, 0)); + + page_table_check_pte_clear(mm, addr, old_pte); + + return old_pte; } #define __HAVE_ARCH_PTEP_SET_WRPROTECT --- a/arch/powerpc/include/asm/book3s/64/pgtable.h~powerpc-mm-support-page-table-check +++ a/arch/powerpc/include/asm/book3s/64/pgtable.h @@ -144,6 +144,8 @@ #define PAGE_KERNEL_ROX __pgprot(_PAGE_BASE | _PAGE_KERNEL_ROX) #ifndef __ASSEMBLER__ +#include + /* * page table defines */ @@ -416,8 +418,11 @@ static inline void huge_ptep_set_wrprote static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - unsigned long old = pte_update(mm, addr, ptep, ~0UL, 0, 0); - return __pte(old); + pte_t old_pte = __pte(pte_update(mm, addr, ptep, ~0UL, 0, 0)); + + page_table_check_pte_clear(mm, addr, old_pte); + + return old_pte; } #define __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL @@ -426,11 +431,16 @@ static inline pte_t ptep_get_and_clear_f pte_t *ptep, int full) { if (full && radix_enabled()) { + pte_t old_pte; + /* * We know that this is a full mm pte clear and * hence can be sure there is no parallel set_pte. */ - return radix__ptep_get_and_clear_full(mm, addr, ptep, full); + old_pte = radix__ptep_get_and_clear_full(mm, addr, ptep, full); + page_table_check_pte_clear(mm, addr, old_pte); + + return old_pte; } return ptep_get_and_clear(mm, addr, ptep); } @@ -1301,19 +1311,34 @@ extern int pudp_test_and_clear_young(str static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm, unsigned long addr, pmd_t *pmdp) { - if (radix_enabled()) - return radix__pmdp_huge_get_and_clear(mm, addr, pmdp); - return hash__pmdp_huge_get_and_clear(mm, addr, pmdp); + pmd_t old_pmd; + + if (radix_enabled()) { + old_pmd = radix__pmdp_huge_get_and_clear(mm, addr, pmdp); + } else { + old_pmd = hash__pmdp_huge_get_and_clear(mm, addr, pmdp); + } + + page_table_check_pmd_clear(mm, addr, old_pmd); + + return old_pmd; } #define __HAVE_ARCH_PUDP_HUGE_GET_AND_CLEAR static inline pud_t pudp_huge_get_and_clear(struct mm_struct *mm, unsigned long addr, pud_t *pudp) { - if (radix_enabled()) - return radix__pudp_huge_get_and_clear(mm, addr, pudp); - BUG(); - return *pudp; + pud_t old_pud; + + if (radix_enabled()) { + old_pud = radix__pudp_huge_get_and_clear(mm, addr, pudp); + } else { + BUG(); + } + + page_table_check_pud_clear(mm, addr, old_pud); + + return old_pud; } static inline pmd_t pmdp_collapse_flush(struct vm_area_struct *vma, --- a/arch/powerpc/include/asm/nohash/pgtable.h~powerpc-mm-support-page-table-check +++ a/arch/powerpc/include/asm/nohash/pgtable.h @@ -29,6 +29,8 @@ static inline pte_basic_t pte_update(str #ifndef __ASSEMBLER__ +#include + extern int icache_44x_need_flush; #ifndef pte_huge_size @@ -122,7 +124,11 @@ static inline void ptep_set_wrprotect(st static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - return __pte(pte_update(mm, addr, ptep, ~0UL, 0, 0)); + pte_t old_pte = __pte(pte_update(mm, addr, ptep, ~0UL, 0, 0)); + + page_table_check_pte_clear(mm, addr, old_pte); + + return old_pte; } #define __HAVE_ARCH_PTEP_GET_AND_CLEAR --- a/arch/powerpc/Kconfig~powerpc-mm-support-page-table-check +++ a/arch/powerpc/Kconfig @@ -172,6 +172,7 @@ config PPC select ARCH_STACKWALK select ARCH_SUPPORTS_ATOMIC_RMW select ARCH_SUPPORTS_DEBUG_PAGEALLOC if PPC_BOOK3S || PPC_8xx + select ARCH_SUPPORTS_PAGE_TABLE_CHECK if !HUGETLB_PAGE select ARCH_SUPPORTS_SCHED_MC if SMP select ARCH_SUPPORTS_SCHED_SMT if PPC64 && SMP select SCHED_MC if ARCH_SUPPORTS_SCHED_MC --- a/arch/powerpc/mm/book3s64/hash_pgtable.c~powerpc-mm-support-page-table-check +++ a/arch/powerpc/mm/book3s64/hash_pgtable.c @@ -8,6 +8,7 @@ #include #include #include +#include #include #include @@ -230,6 +231,9 @@ pmd_t hash__pmdp_collapse_flush(struct v pmd = *pmdp; pmd_clear(pmdp); + + page_table_check_pmd_clear(vma->vm_mm, address, pmd); + /* * Wait for all pending hash_page to finish. This is needed * in case of subpage collapse. When we collapse normal pages --- a/arch/powerpc/mm/book3s64/pgtable.c~powerpc-mm-support-page-table-check +++ a/arch/powerpc/mm/book3s64/pgtable.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include @@ -127,6 +128,7 @@ void set_pmd_at(struct mm_struct *mm, un WARN_ON(!(pmd_leaf(pmd))); #endif trace_hugepage_set_pmd(addr, pmd_val(pmd)); + page_table_check_pmd_set(mm, addr, pmdp, pmd); return set_pte_at_unchecked(mm, addr, pmdp_ptep(pmdp), pmd_pte(pmd)); } @@ -144,6 +146,7 @@ void set_pud_at(struct mm_struct *mm, un WARN_ON(!(pud_leaf(pud))); #endif trace_hugepage_set_pud(addr, pud_val(pud)); + page_table_check_pud_set(mm, addr, pudp, pud); return set_pte_at_unchecked(mm, addr, pudp_ptep(pudp), pud_pte(pud)); } @@ -179,23 +182,27 @@ void serialize_against_pte_lookup(struct pmd_t pmdp_invalidate(struct vm_area_struct *vma, unsigned long address, pmd_t *pmdp) { - unsigned long old_pmd; + pmd_t old_pmd; VM_WARN_ON_ONCE(!pmd_present(*pmdp)); - old_pmd = pmd_hugepage_update(vma->vm_mm, address, pmdp, _PAGE_PRESENT, _PAGE_INVALID); + old_pmd = __pmd(pmd_hugepage_update(vma->vm_mm, address, pmdp, _PAGE_PRESENT, _PAGE_INVALID)); flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE); - return __pmd(old_pmd); + page_table_check_pmd_clear(vma->vm_mm, address, old_pmd); + + return old_pmd; } pud_t pudp_invalidate(struct vm_area_struct *vma, unsigned long address, pud_t *pudp) { - unsigned long old_pud; + pud_t old_pud; VM_WARN_ON_ONCE(!pud_present(*pudp)); - old_pud = pud_hugepage_update(vma->vm_mm, address, pudp, _PAGE_PRESENT, _PAGE_INVALID); + old_pud = __pud(pud_hugepage_update(vma->vm_mm, address, pudp, _PAGE_PRESENT, _PAGE_INVALID)); flush_pud_tlb_range(vma, address, address + HPAGE_PUD_SIZE); - return __pud(old_pud); + page_table_check_pud_clear(vma->vm_mm, address, old_pud); + + return old_pud; } pmd_t pmdp_huge_get_and_clear_full(struct vm_area_struct *vma, --- a/arch/powerpc/mm/book3s64/radix_pgtable.c~powerpc-mm-support-page-table-check +++ a/arch/powerpc/mm/book3s64/radix_pgtable.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -1474,6 +1475,8 @@ pmd_t radix__pmdp_collapse_flush(struct pmd = *pmdp; pmd_clear(pmdp); + page_table_check_pmd_clear(vma->vm_mm, address, pmd); + radix__flush_tlb_collapsed_pmd(vma->vm_mm, address); return pmd; --- a/arch/powerpc/mm/pgtable.c~powerpc-mm-support-page-table-check +++ a/arch/powerpc/mm/pgtable.c @@ -22,6 +22,7 @@ #include #include #include +#include #include #include #include @@ -206,6 +207,9 @@ void set_ptes(struct mm_struct *mm, unsi * and not hw_valid ptes. Hence there is no translation cache flush * involved that need to be batched. */ + + page_table_check_ptes_set(mm, addr, ptep, pte, nr); + for (;;) { /* _ Patches currently in -mm which might be from rmclure@linux.ibm.com are mm-page_table_check-reinstate-address-parameter-in-page_table_check_pud_set.patch mm-page_table_check-reinstate-address-parameter-in-page_table_check_pmd_set.patch mm-page_table_check-provide-addr-parameter-to-page_table_check_ptes_set.patch mm-page_table_check-reinstate-address-parameter-in-page_table_check_pud_clear.patch mm-page_table_check-reinstate-address-parameter-in-page_table_check_pmd_clear.patch mm-page_table_check-reinstate-address-parameter-in-page_table_check_pte_clear.patch mm-provide-address-parameter-to-ptemdud_user_accessible_page.patch powerpc-mm-implement-_user_accessible_page-for-ptes.patch powerpc-mm-use-set_pte_at_unchecked-for-internal-usages.patch powerpc-mm-support-page-table-check.patch