From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 8B20B43F8AF; Tue, 14 Jul 2026 14:05:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784037943; cv=none; b=U2LZVYzX8NTONM3RVmMYQNPC0l6uhs0s/5BbQ1gsBUrk8QC0hdCynQiAZ+uiVd5nnKvFYMkqJH1t21FR7hq9qJ+8Umzp2jJOY9bKtfcAZlcpJc4r6ZMrsWGOWrX+M/wi4i4s8EzEfC5jwbOdJ97ne4Y50FVBbbUA7WZju6ozDQw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784037943; c=relaxed/simple; bh=5/MiBpHs0ErPi8rhCKmMSpm6ldHtuokM4yv1ELNR2HE=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=n+mCVUpCMgUpnKl1aBQg+DD6lLXdV9ykO0AmAqYvs5SJTo/5/y/aS1Gkrm98iVX+4W3wdabYlNHGpjwZ1YQHpQT/6j9f65IcnagCSS6Zn1+0kyHnt1SF8nyQxxxef11TFzT1hO7a2oiDUc3bpHW3IQlZJqYXsEYhofpHcTZnyfE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=KYO9cDN7; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="KYO9cDN7" Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id CDF1F1516; Tue, 14 Jul 2026 07:05:36 -0700 (PDT) Received: from localhost.localdomain (e123572-lin.cambridge.arm.com [10.2.208.46]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id A8C023F7B4; Tue, 14 Jul 2026 07:05:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1784037941; bh=5/MiBpHs0ErPi8rhCKmMSpm6ldHtuokM4yv1ELNR2HE=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=KYO9cDN7rDizxe3v/je6cSxNCJeEVFPUnXsSWSe2BPhKaPCn7aqwcwGf5Fv/X2xeM fJX9X0ToA3Vm5csdSfShGsy263erMfQnPGfY2VsiME2prC8a3J844A9rhhh46ZY371 B0aQM0b2gjQo2R4Q0Ts/ynPMN9wstMhZsk8mylek= From: Kevin Brodsky Date: Tue, 14 Jul 2026 15:03:53 +0100 Subject: [PATCH 04/22] mm: use mm_is_kernel() in generic page table code Precedence: bulk X-Mailing-List: linux-efi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260714-remove_pgtable_cdtor-v1-4-44be8a7685d7@arm.com> References: <20260714-remove_pgtable_cdtor-v1-0-44be8a7685d7@arm.com> In-Reply-To: <20260714-remove_pgtable_cdtor-v1-0-44be8a7685d7@arm.com> To: linux-mm@kvack.org Cc: Kevin Brodsky , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Pasha Tatashin , Russell King , Catalin Marinas , Will Deacon , Ryan Roberts , linux-arm-kernel@lists.infradead.org, Huacai Chen , loongarch@lists.linux.dev, "James E.J. Bottomley" , Helge Deller , linux-parisc@vger.kernel.org, Madhavan Srinivasan , Michael Ellerman , linuxppc-dev@lists.ozlabs.org, Paul Walmsley , Palmer Dabbelt , Albert Ou , linux-riscv@lists.infradead.org, Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Gerald Schaefer , linux-s390@vger.kernel.org, "David S. Miller" , Andreas Larsson , sparclinux@vger.kernel.org, Richard Weinberger , Anton Ivanov , Johannes Berg , linux-um@lists.infradead.org, Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Andy Lutomirski , Peter Zijlstra , Ning Sun , x86@kernel.org, tboot-devel@lists.sourceforge.net, Ard Biesheuvel , Ilias Apalodimas , linux-efi@vger.kernel.org, Vishal Moola , Alistair Popple , "Matthew Wilcox (Oracle)" , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org X-Mailer: b4 0.15.2 X-Developer-Signature: v=1; a=ed25519-sha256; t=1784037902; l=7589; i=kevin.brodsky@arm.com; s=20260427; h=from:subject:message-id; bh=5/MiBpHs0ErPi8rhCKmMSpm6ldHtuokM4yv1ELNR2HE=; b=uo2OhW6qUc5pqzt9VsrUNdo1IYgeBBnT6lqfK5Ys8RZJ6rVRF5aIis0fNbkhks1ozPQyi/VUC pyQWphyWV1oCOOAp4DOjVmApiSewKKEeH9vCDbxc96BlDrMTGs1NvYU X-Developer-Key: i=kevin.brodsky@arm.com; a=ed25519; pk=N2QG+eJKrvkNovwhhwJhnJ4+ScVfsGCHldmqLfcMTFs= Generic page-table allocation, constructor and walker code uses init_mm comparisons to select kernel page table handling. Use mm_is_kernel() instead so kernel-owned mm's can share that handling once they are marked with MMF_KERNEL. No functional change as only init_mm has MMF_KERNEL set for now. Assisted-by: Codex:GPT-5.5 Signed-off-by: Kevin Brodsky --- include/asm-generic/pgalloc.h | 16 ++++++++-------- include/linux/mm.h | 4 ++-- mm/memory.c | 6 +++--- mm/page_table_check.c | 14 +++++++------- mm/pagewalk.c | 4 ++-- 5 files changed, 22 insertions(+), 22 deletions(-) diff --git a/include/asm-generic/pgalloc.h b/include/asm-generic/pgalloc.h index 051aa1331051..a283280e3140 100644 --- a/include/asm-generic/pgalloc.h +++ b/include/asm-generic/pgalloc.h @@ -138,7 +138,7 @@ static inline pmd_t *pmd_alloc_one_noprof(struct mm_struct *mm, unsigned long ad struct ptdesc *ptdesc; gfp_t gfp = GFP_PGTABLE_USER; - if (mm == &init_mm) + if (mm_is_kernel(mm)) gfp = GFP_PGTABLE_KERNEL; ptdesc = pagetable_alloc_noprof(gfp, 0); if (!ptdesc) @@ -148,7 +148,7 @@ static inline pmd_t *pmd_alloc_one_noprof(struct mm_struct *mm, unsigned long ad return NULL; } - if (mm == &init_mm) + if (mm_is_kernel(mm)) ptdesc_set_kernel(ptdesc); return ptdesc_address(ptdesc); @@ -175,7 +175,7 @@ static inline pud_t *__pud_alloc_one_noprof(struct mm_struct *mm, unsigned long gfp_t gfp = GFP_PGTABLE_USER; struct ptdesc *ptdesc; - if (mm == &init_mm) + if (mm_is_kernel(mm)) gfp = GFP_PGTABLE_KERNEL; ptdesc = pagetable_alloc_noprof(gfp, 0); @@ -184,7 +184,7 @@ static inline pud_t *__pud_alloc_one_noprof(struct mm_struct *mm, unsigned long pagetable_pud_ctor(ptdesc); - if (mm == &init_mm) + if (mm_is_kernel(mm)) ptdesc_set_kernel(ptdesc); return ptdesc_address(ptdesc); @@ -232,7 +232,7 @@ static inline p4d_t *__p4d_alloc_one_noprof(struct mm_struct *mm, unsigned long gfp_t gfp = GFP_PGTABLE_USER; struct ptdesc *ptdesc; - if (mm == &init_mm) + if (mm_is_kernel(mm)) gfp = GFP_PGTABLE_KERNEL; ptdesc = pagetable_alloc_noprof(gfp, 0); @@ -241,7 +241,7 @@ static inline p4d_t *__p4d_alloc_one_noprof(struct mm_struct *mm, unsigned long pagetable_p4d_ctor(ptdesc); - if (mm == &init_mm) + if (mm_is_kernel(mm)) ptdesc_set_kernel(ptdesc); return ptdesc_address(ptdesc); @@ -279,7 +279,7 @@ static inline pgd_t *__pgd_alloc_noprof(struct mm_struct *mm, unsigned int order gfp_t gfp = GFP_PGTABLE_USER; struct ptdesc *ptdesc; - if (mm == &init_mm) + if (mm_is_kernel(mm)) gfp = GFP_PGTABLE_KERNEL; ptdesc = pagetable_alloc_noprof(gfp, order); @@ -288,7 +288,7 @@ static inline pgd_t *__pgd_alloc_noprof(struct mm_struct *mm, unsigned int order pagetable_pgd_ctor(ptdesc); - if (mm == &init_mm) + if (mm_is_kernel(mm)) ptdesc_set_kernel(ptdesc); return ptdesc_address(ptdesc); diff --git a/include/linux/mm.h b/include/linux/mm.h index 7a4b8e7ac8f4..b336eb32faa0 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3818,7 +3818,7 @@ static inline void pagetable_dtor_free(struct ptdesc *ptdesc) static inline bool pagetable_pte_ctor(struct mm_struct *mm, struct ptdesc *ptdesc) { - if (mm != &init_mm && !ptlock_init(ptdesc)) + if (!mm_is_kernel(mm) && !ptlock_init(ptdesc)) return false; __pagetable_ctor(ptdesc); return true; @@ -3909,7 +3909,7 @@ static inline spinlock_t *pmd_lock(struct mm_struct *mm, pmd_t *pmd) static inline bool pagetable_pmd_ctor(struct mm_struct *mm, struct ptdesc *ptdesc) { - if (mm != &init_mm && !pmd_ptlock_init(ptdesc)) + if (!mm_is_kernel(mm) && !pmd_ptlock_init(ptdesc)) return false; ptdesc_pmd_pts_init(ptdesc); __pagetable_ctor(ptdesc); diff --git a/mm/memory.c b/mm/memory.c index d5e87624f692..c0244c0b0756 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3394,13 +3394,13 @@ static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd, spinlock_t *ptl; if (create) { - mapped_pte = pte = (mm == &init_mm) ? + mapped_pte = pte = mm_is_kernel(mm) ? pte_alloc_kernel_track(pmd, addr, mask) : pte_alloc_map_lock(mm, pmd, addr, &ptl); if (!pte) return -ENOMEM; } else { - mapped_pte = pte = (mm == &init_mm) ? + mapped_pte = pte = mm_is_kernel(mm) ? pte_offset_kernel(pmd, addr) : pte_offset_map_lock(mm, pmd, addr, &ptl); if (!pte) @@ -3422,7 +3422,7 @@ static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd, lazy_mmu_mode_disable(); - if (mm != &init_mm) + if (!mm_is_kernel(mm)) pte_unmap_unlock(mapped_pte, ptl); return err; } diff --git a/mm/page_table_check.c b/mm/page_table_check.c index 3fb995e5d40d..a5382c245b32 100644 --- a/mm/page_table_check.c +++ b/mm/page_table_check.c @@ -148,7 +148,7 @@ void __page_table_check_zero(struct page *page, unsigned int order) void __page_table_check_pte_clear(struct mm_struct *mm, unsigned long addr, pte_t pte) { - if (&init_mm == mm) + if (mm_is_kernel(mm)) return; if (pte_user_accessible_page(mm, addr, pte)) @@ -159,7 +159,7 @@ EXPORT_SYMBOL(__page_table_check_pte_clear); void __page_table_check_pmd_clear(struct mm_struct *mm, unsigned long addr, pmd_t pmd) { - if (&init_mm == mm) + if (mm_is_kernel(mm)) return; if (pmd_user_accessible_page(mm, addr, pmd)) @@ -170,7 +170,7 @@ EXPORT_SYMBOL(__page_table_check_pmd_clear); void __page_table_check_pud_clear(struct mm_struct *mm, unsigned long addr, pud_t pud) { - if (&init_mm == mm) + if (mm_is_kernel(mm)) return; if (pud_user_accessible_page(mm, addr, pud)) @@ -201,7 +201,7 @@ void __page_table_check_ptes_set(struct mm_struct *mm, unsigned long addr, { unsigned int i; - if (&init_mm == mm) + if (mm_is_kernel(mm)) return; page_table_check_pte_flags(pte); @@ -231,7 +231,7 @@ void __page_table_check_pmds_set(struct mm_struct *mm, unsigned long addr, unsigned long stride = PMD_SIZE >> PAGE_SHIFT; unsigned int i; - if (&init_mm == mm) + if (mm_is_kernel(mm)) return; page_table_check_pmd_flags(pmd); @@ -249,7 +249,7 @@ void __page_table_check_puds_set(struct mm_struct *mm, unsigned long addr, unsigned long stride = PUD_SIZE >> PAGE_SHIFT; unsigned int i; - if (&init_mm == mm) + if (mm_is_kernel(mm)) return; for (i = 0; i < nr; i++) @@ -263,7 +263,7 @@ void __page_table_check_pte_clear_range(struct mm_struct *mm, unsigned long addr, pmd_t pmd) { - if (&init_mm == mm) + if (mm_is_kernel(mm)) return; if (!pmd_bad(pmd) && !pmd_leaf(pmd)) { diff --git a/mm/pagewalk.c b/mm/pagewalk.c index ed4860c01936..a3f47d1de3c5 100644 --- a/mm/pagewalk.c +++ b/mm/pagewalk.c @@ -72,13 +72,13 @@ static int walk_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, * fit its pmd_bad() check (_PAGE_NX set and _PAGE_RW clear), * and CONFIG_EFI_PGT_DUMP efi_mm goes so far as to walk them. */ - if (walk->mm == &init_mm || addr >= TASK_SIZE) + if (mm_is_kernel(walk->mm) || addr >= TASK_SIZE) pte = pte_offset_kernel(pmd, addr); else pte = pte_offset_map(pmd, addr); if (pte) { err = walk_pte_range_inner(pte, addr, end, walk); - if (walk->mm != &init_mm && addr < TASK_SIZE) + if (!mm_is_kernel(walk->mm) && addr < TASK_SIZE) pte_unmap(pte); } } else { -- 2.51.2