From patchwork Tue Apr 8 09:52:11 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Brodsky X-Patchwork-Id: 14042673 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id AA3D8C369A1 for ; Tue, 8 Apr 2025 10:26:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=H3XPZUFeB3j0oUqZhyoJ7SKF30TvT5YWB8oVd5GbDSs=; b=IJkLcx2TezM21H5fNAqvmp9JwE 2K6XReealkamblwC0p1pvNY599pRQuDwZdQo83HJMGjJvHlvghbhL2p/WWSU+E1Qzuo+s9Gz1MwRl V3Ytj386UOT+Tkf6bEv6I5KQuvGL/RSSRy2dEeV+N5qbK1fNxkv9FFOspgffcN+Gu22rrGFPf7wzj stUq9VMp12OZJAlu675DMS/jvZXA3fTGRxd0ft8rJc3Uw2d3IjRYVKEON5EFksnt2pBCwjbCdX3vb vQ66ElknrLBrEjllSqPSGNAcGIyUbnbqrs7n8PCbamgmGhaQTK13K3XwqsT+6YsVk0PG6UxwX5UdC 6uTtPFHA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u26A3-00000003eYD-3O2F; Tue, 08 Apr 2025 10:26:31 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u25dr-00000003WS6-2SnB; Tue, 08 Apr 2025 09:53:21 +0000 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 021EA1691; Tue, 8 Apr 2025 02:53:16 -0700 (PDT) Received: from e123572-lin.arm.com (e123572-lin.cambridge.arm.com [10.1.194.54]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 98B8B3F6A8; Tue, 8 Apr 2025 02:53:10 -0700 (PDT) From: Kevin Brodsky To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Kevin Brodsky , Albert Ou , Andreas Larsson , Andrew Morton , Catalin Marinas , Dave Hansen , "David S. Miller" , Geert Uytterhoeven , Linus Walleij , Madhavan Srinivasan , Mark Rutland , Matthew Wilcox , Michael Ellerman , "Mike Rapoport (IBM)" , Palmer Dabbelt , Paul Walmsley , Peter Zijlstra , Qi Zheng , Ryan Roberts , Will Deacon , Yang Shi , linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-openrisc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, x86@kernel.org Subject: [PATCH v2 01/12] mm: Pass mm down to pagetable_{pte,pmd}_ctor Date: Tue, 8 Apr 2025 10:52:11 +0100 Message-ID: <20250408095222.860601-2-kevin.brodsky@arm.com> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20250408095222.860601-1-kevin.brodsky@arm.com> References: <20250408095222.860601-1-kevin.brodsky@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250408_025315_719943_2A491462 X-CRM114-Status: GOOD ( 20.83 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org In preparation for calling constructors for all kernel page tables while eliding unnecessary ptlock initialisation, let's pass down the associated mm to the PTE/PMD level ctors. (These are the two levels where ptlocks are used.) In most cases the mm is already around at the point of calling the ctor so we simply pass it down. This is however not the case for special page table allocators: * arch/arm/mm/mmu.c * arch/arm64/mm/mmu.c * arch/riscv/mm/init.c In those cases, the page tables being allocated are either for standard kernel memory (init_mm) or special page directories, which may not be associated to any mm. For now let's pass NULL as mm; this will be refined where possible in future patches. No functional change in this patch. Signed-off-by: Kevin Brodsky --- arch/arm/mm/mmu.c | 2 +- arch/arm64/mm/mmu.c | 4 ++-- arch/loongarch/include/asm/pgalloc.h | 2 +- arch/m68k/include/asm/mcf_pgalloc.h | 2 +- arch/m68k/include/asm/motorola_pgalloc.h | 10 +++++----- arch/m68k/mm/motorola.c | 6 +++--- arch/mips/include/asm/pgalloc.h | 2 +- arch/parisc/include/asm/pgalloc.h | 2 +- arch/powerpc/mm/book3s64/pgtable.c | 2 +- arch/powerpc/mm/pgtable-frag.c | 2 +- arch/riscv/mm/init.c | 4 ++-- arch/s390/include/asm/pgalloc.h | 2 +- arch/s390/mm/pgalloc.c | 2 +- arch/sparc/mm/init_64.c | 2 +- arch/sparc/mm/srmmu.c | 2 +- arch/x86/mm/pgtable.c | 2 +- include/asm-generic/pgalloc.h | 4 ++-- include/linux/mm.h | 6 ++++-- 18 files changed, 30 insertions(+), 28 deletions(-) diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c index f02f872ea8a9..edb7f56b7c91 100644 --- a/arch/arm/mm/mmu.c +++ b/arch/arm/mm/mmu.c @@ -735,7 +735,7 @@ static void *__init late_alloc(unsigned long sz) void *ptdesc = pagetable_alloc(GFP_PGTABLE_KERNEL & ~__GFP_HIGHMEM, get_order(sz)); - if (!ptdesc || !pagetable_pte_ctor(ptdesc)) + if (!ptdesc || !pagetable_pte_ctor(NULL, ptdesc)) BUG(); return ptdesc_to_virt(ptdesc); } diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index ea6695d53fb9..8c5c471cfb06 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -494,9 +494,9 @@ static phys_addr_t pgd_pgtable_alloc(int shift) * folded, and if so pagetable_pte_ctor() becomes nop. */ if (shift == PAGE_SHIFT) - BUG_ON(!pagetable_pte_ctor(ptdesc)); + BUG_ON(!pagetable_pte_ctor(NULL, ptdesc)); else if (shift == PMD_SHIFT) - BUG_ON(!pagetable_pmd_ctor(ptdesc)); + BUG_ON(!pagetable_pmd_ctor(NULL, ptdesc)); return pa; } diff --git a/arch/loongarch/include/asm/pgalloc.h b/arch/loongarch/include/asm/pgalloc.h index b58f587f0f0a..1c63a9d9a6d3 100644 --- a/arch/loongarch/include/asm/pgalloc.h +++ b/arch/loongarch/include/asm/pgalloc.h @@ -69,7 +69,7 @@ static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address) if (!ptdesc) return NULL; - if (!pagetable_pmd_ctor(ptdesc)) { + if (!pagetable_pmd_ctor(mm, ptdesc)) { pagetable_free(ptdesc); return NULL; } diff --git a/arch/m68k/include/asm/mcf_pgalloc.h b/arch/m68k/include/asm/mcf_pgalloc.h index 4c648b51e7fd..465a71101b7d 100644 --- a/arch/m68k/include/asm/mcf_pgalloc.h +++ b/arch/m68k/include/asm/mcf_pgalloc.h @@ -48,7 +48,7 @@ static inline pgtable_t pte_alloc_one(struct mm_struct *mm) if (!ptdesc) return NULL; - if (!pagetable_pte_ctor(ptdesc)) { + if (!pagetable_pte_ctor(mm, ptdesc)) { pagetable_free(ptdesc); return NULL; } diff --git a/arch/m68k/include/asm/motorola_pgalloc.h b/arch/m68k/include/asm/motorola_pgalloc.h index 5abe7da8ac5a..1091fb0affbe 100644 --- a/arch/m68k/include/asm/motorola_pgalloc.h +++ b/arch/m68k/include/asm/motorola_pgalloc.h @@ -15,7 +15,7 @@ enum m68k_table_types { }; extern void init_pointer_table(void *table, int type); -extern void *get_pointer_table(int type); +extern void *get_pointer_table(struct mm_struct *mm, int type); extern int free_pointer_table(void *table, int type); /* @@ -26,7 +26,7 @@ extern int free_pointer_table(void *table, int type); static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm) { - return get_pointer_table(TABLE_PTE); + return get_pointer_table(mm, TABLE_PTE); } static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte) @@ -36,7 +36,7 @@ static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte) static inline pgtable_t pte_alloc_one(struct mm_struct *mm) { - return get_pointer_table(TABLE_PTE); + return get_pointer_table(mm, TABLE_PTE); } static inline void pte_free(struct mm_struct *mm, pgtable_t pgtable) @@ -53,7 +53,7 @@ static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pgtable, static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address) { - return get_pointer_table(TABLE_PMD); + return get_pointer_table(mm, TABLE_PMD); } static inline int pmd_free(struct mm_struct *mm, pmd_t *pmd) @@ -75,7 +75,7 @@ static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd) static inline pgd_t *pgd_alloc(struct mm_struct *mm) { - return get_pointer_table(TABLE_PGD); + return get_pointer_table(mm, TABLE_PGD); } diff --git a/arch/m68k/mm/motorola.c b/arch/m68k/mm/motorola.c index 73651e093c4d..6ab3ef39ba7a 100644 --- a/arch/m68k/mm/motorola.c +++ b/arch/m68k/mm/motorola.c @@ -139,7 +139,7 @@ void __init init_pointer_table(void *table, int type) return; } -void *get_pointer_table(int type) +void *get_pointer_table(struct mm_struct *mm, int type) { ptable_desc *dp = ptable_list[type].next; unsigned int mask = list_empty(&ptable_list[type]) ? 0 : PD_MARKBITS(dp); @@ -164,10 +164,10 @@ void *get_pointer_table(int type) * m68k doesn't have SPLIT_PTE_PTLOCKS for not having * SMP. */ - pagetable_pte_ctor(virt_to_ptdesc(page)); + pagetable_pte_ctor(mm, virt_to_ptdesc(page)); break; case TABLE_PMD: - pagetable_pmd_ctor(virt_to_ptdesc(page)); + pagetable_pmd_ctor(mm, virt_to_ptdesc(page)); break; case TABLE_PGD: pagetable_pgd_ctor(virt_to_ptdesc(page)); diff --git a/arch/mips/include/asm/pgalloc.h b/arch/mips/include/asm/pgalloc.h index bbca420c96d3..942af87f1cdd 100644 --- a/arch/mips/include/asm/pgalloc.h +++ b/arch/mips/include/asm/pgalloc.h @@ -62,7 +62,7 @@ static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address) if (!ptdesc) return NULL; - if (!pagetable_pmd_ctor(ptdesc)) { + if (!pagetable_pmd_ctor(mm, ptdesc)) { pagetable_free(ptdesc); return NULL; } diff --git a/arch/parisc/include/asm/pgalloc.h b/arch/parisc/include/asm/pgalloc.h index 2ca74a56415c..3b84ee93edaa 100644 --- a/arch/parisc/include/asm/pgalloc.h +++ b/arch/parisc/include/asm/pgalloc.h @@ -39,7 +39,7 @@ static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address) ptdesc = pagetable_alloc(gfp, PMD_TABLE_ORDER); if (!ptdesc) return NULL; - if (!pagetable_pmd_ctor(ptdesc)) { + if (!pagetable_pmd_ctor(mm, ptdesc)) { pagetable_free(ptdesc); return NULL; } diff --git a/arch/powerpc/mm/book3s64/pgtable.c b/arch/powerpc/mm/book3s64/pgtable.c index 8f7d41ce2ca1..a282233c8785 100644 --- a/arch/powerpc/mm/book3s64/pgtable.c +++ b/arch/powerpc/mm/book3s64/pgtable.c @@ -422,7 +422,7 @@ static pmd_t *__alloc_for_pmdcache(struct mm_struct *mm) ptdesc = pagetable_alloc(gfp, 0); if (!ptdesc) return NULL; - if (!pagetable_pmd_ctor(ptdesc)) { + if (!pagetable_pmd_ctor(mm, ptdesc)) { pagetable_free(ptdesc); return NULL; } diff --git a/arch/powerpc/mm/pgtable-frag.c b/arch/powerpc/mm/pgtable-frag.c index 713268ccb1a0..387e9b1fe12c 100644 --- a/arch/powerpc/mm/pgtable-frag.c +++ b/arch/powerpc/mm/pgtable-frag.c @@ -61,7 +61,7 @@ static pte_t *__alloc_for_ptecache(struct mm_struct *mm, int kernel) ptdesc = pagetable_alloc(PGALLOC_GFP | __GFP_ACCOUNT, 0); if (!ptdesc) return NULL; - if (!pagetable_pte_ctor(ptdesc)) { + if (!pagetable_pte_ctor(mm, ptdesc)) { pagetable_free(ptdesc); return NULL; } diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index ab475ec6ca42..e5ef693fc778 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -442,7 +442,7 @@ static phys_addr_t __meminit alloc_pte_late(uintptr_t va) { struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0); - BUG_ON(!ptdesc || !pagetable_pte_ctor(ptdesc)); + BUG_ON(!ptdesc || !pagetable_pte_ctor(NULL, ptdesc)); return __pa((pte_t *)ptdesc_address(ptdesc)); } @@ -522,7 +522,7 @@ static phys_addr_t __meminit alloc_pmd_late(uintptr_t va) { struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0); - BUG_ON(!ptdesc || !pagetable_pmd_ctor(ptdesc)); + BUG_ON(!ptdesc || !pagetable_pmd_ctor(NULL, ptdesc)); return __pa((pmd_t *)ptdesc_address(ptdesc)); } diff --git a/arch/s390/include/asm/pgalloc.h b/arch/s390/include/asm/pgalloc.h index 005497ffebda..5345398df653 100644 --- a/arch/s390/include/asm/pgalloc.h +++ b/arch/s390/include/asm/pgalloc.h @@ -97,7 +97,7 @@ static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long vmaddr) if (!table) return NULL; crst_table_init(table, _SEGMENT_ENTRY_EMPTY); - if (!pagetable_pmd_ctor(virt_to_ptdesc(table))) { + if (!pagetable_pmd_ctor(mm, virt_to_ptdesc(table))) { crst_table_free(mm, table); return NULL; } diff --git a/arch/s390/mm/pgalloc.c b/arch/s390/mm/pgalloc.c index e3a6f8ae156c..619d6917e3b7 100644 --- a/arch/s390/mm/pgalloc.c +++ b/arch/s390/mm/pgalloc.c @@ -145,7 +145,7 @@ unsigned long *page_table_alloc(struct mm_struct *mm) ptdesc = pagetable_alloc(GFP_KERNEL, 0); if (!ptdesc) return NULL; - if (!pagetable_pte_ctor(ptdesc)) { + if (!pagetable_pte_ctor(mm, ptdesc)) { pagetable_free(ptdesc); return NULL; } diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c index 760818950464..5c8eabda1d17 100644 --- a/arch/sparc/mm/init_64.c +++ b/arch/sparc/mm/init_64.c @@ -2895,7 +2895,7 @@ pgtable_t pte_alloc_one(struct mm_struct *mm) if (!ptdesc) return NULL; - if (!pagetable_pte_ctor(ptdesc)) { + if (!pagetable_pte_ctor(mm, ptdesc)) { pagetable_free(ptdesc); return NULL; } diff --git a/arch/sparc/mm/srmmu.c b/arch/sparc/mm/srmmu.c index dd32711022f5..f8fb4911d360 100644 --- a/arch/sparc/mm/srmmu.c +++ b/arch/sparc/mm/srmmu.c @@ -350,7 +350,7 @@ pgtable_t pte_alloc_one(struct mm_struct *mm) page = pfn_to_page(__nocache_pa((unsigned long)ptep) >> PAGE_SHIFT); spin_lock(&mm->page_table_lock); if (page_ref_inc_return(page) == 2 && - !pagetable_pte_ctor(page_ptdesc(page))) { + !pagetable_pte_ctor(mm, page_ptdesc(page))) { page_ref_dec(page); ptep = NULL; } diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c index a05fcddfc811..7930f234c5f6 100644 --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -205,7 +205,7 @@ static int preallocate_pmds(struct mm_struct *mm, pmd_t *pmds[], int count) if (!ptdesc) failed = true; - if (ptdesc && !pagetable_pmd_ctor(ptdesc)) { + if (ptdesc && !pagetable_pmd_ctor(mm, ptdesc)) { pagetable_free(ptdesc); ptdesc = NULL; failed = true; diff --git a/include/asm-generic/pgalloc.h b/include/asm-generic/pgalloc.h index 892ece4558a2..e164ca66f0f6 100644 --- a/include/asm-generic/pgalloc.h +++ b/include/asm-generic/pgalloc.h @@ -70,7 +70,7 @@ static inline pgtable_t __pte_alloc_one_noprof(struct mm_struct *mm, gfp_t gfp) ptdesc = pagetable_alloc_noprof(gfp, 0); if (!ptdesc) return NULL; - if (!pagetable_pte_ctor(ptdesc)) { + if (!pagetable_pte_ctor(mm, ptdesc)) { pagetable_free(ptdesc); return NULL; } @@ -137,7 +137,7 @@ static inline pmd_t *pmd_alloc_one_noprof(struct mm_struct *mm, unsigned long ad ptdesc = pagetable_alloc_noprof(gfp, 0); if (!ptdesc) return NULL; - if (!pagetable_pmd_ctor(ptdesc)) { + if (!pagetable_pmd_ctor(mm, ptdesc)) { pagetable_free(ptdesc); return NULL; } diff --git a/include/linux/mm.h b/include/linux/mm.h index b7f13f087954..f9b793cce2c1 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3100,7 +3100,8 @@ static inline void pagetable_dtor_free(struct ptdesc *ptdesc) pagetable_free(ptdesc); } -static inline bool pagetable_pte_ctor(struct ptdesc *ptdesc) +static inline bool pagetable_pte_ctor(struct mm_struct *mm, + struct ptdesc *ptdesc) { if (!ptlock_init(ptdesc)) return false; @@ -3206,7 +3207,8 @@ static inline spinlock_t *pmd_lock(struct mm_struct *mm, pmd_t *pmd) return ptl; } -static inline bool pagetable_pmd_ctor(struct ptdesc *ptdesc) +static inline bool pagetable_pmd_ctor(struct mm_struct *mm, + struct ptdesc *ptdesc) { if (!pmd_ptlock_init(ptdesc)) return false; From patchwork Tue Apr 8 09:52:12 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Brodsky X-Patchwork-Id: 14042674 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 079A1C369A1 for ; 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Tue, 08 Apr 2025 10:28:23 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u25dw-00000003WV4-1DPL; Tue, 08 Apr 2025 09:53:25 +0000 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 AE8B616A3; Tue, 8 Apr 2025 02:53:20 -0700 (PDT) Received: from e123572-lin.arm.com (e123572-lin.cambridge.arm.com [10.1.194.54]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 6F7EA3F6A8; Tue, 8 Apr 2025 02:53:15 -0700 (PDT) From: Kevin Brodsky To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Kevin Brodsky , Albert Ou , Andreas Larsson , Andrew Morton , Catalin Marinas , Dave Hansen , "David S. Miller" , Geert Uytterhoeven , Linus Walleij , Madhavan Srinivasan , Mark Rutland , Matthew Wilcox , Michael Ellerman , "Mike Rapoport (IBM)" , Palmer Dabbelt , Paul Walmsley , Peter Zijlstra , Qi Zheng , Ryan Roberts , Will Deacon , Yang Shi , linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-openrisc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, x86@kernel.org Subject: [PATCH v2 02/12] x86: pgtable: Always use pte_free_kernel() Date: Tue, 8 Apr 2025 10:52:12 +0100 Message-ID: <20250408095222.860601-3-kevin.brodsky@arm.com> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20250408095222.860601-1-kevin.brodsky@arm.com> References: <20250408095222.860601-1-kevin.brodsky@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250408_025320_373080_A7C66AF6 X-CRM114-Status: GOOD ( 12.04 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Page table pages are normally freed using the appropriate helper for the given page table level. On x86, pud_free_pmd_page() and pmd_free_pte_page() are an exception to the rule: they call free_page() directly. Constructor/destructor calls are about to be introduced for kernel PTEs. To avoid missing dtor calls in those helpers, free the PTE pages using pte_free_kernel() instead of free_page(). While at it also use pmd_free() instead of calling pagetable_dtor() explicitly at the PMD level. Signed-off-by: Kevin Brodsky Acked-by: Dave Hansen --- arch/x86/mm/pgtable.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c index 7930f234c5f6..1dee9bdbeea5 100644 --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -809,14 +809,13 @@ int pud_free_pmd_page(pud_t *pud, unsigned long addr) for (i = 0; i < PTRS_PER_PMD; i++) { if (!pmd_none(pmd_sv[i])) { pte = (pte_t *)pmd_page_vaddr(pmd_sv[i]); - free_page((unsigned long)pte); + pte_free_kernel(&init_mm, pte); } } free_page((unsigned long)pmd_sv); - pagetable_dtor(virt_to_ptdesc(pmd)); - free_page((unsigned long)pmd); + pmd_free(&init_mm, pmd); return 1; } @@ -839,7 +838,7 @@ int pmd_free_pte_page(pmd_t *pmd, unsigned long addr) /* INVLPG to clear all paging-structure caches */ flush_tlb_kernel_range(addr, addr + PAGE_SIZE-1); - free_page((unsigned long)pte); + pte_free_kernel(&init_mm, pte); return 1; } From patchwork Tue Apr 8 09:52:13 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Brodsky X-Patchwork-Id: 14042691 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id F07BBC3600C for ; Tue, 8 Apr 2025 10:30:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=EU3IKg5gNWi8e73Hj4jkz8q3EV56066wj6qzlOZeFZQ=; b=XZeBTeypzXFW1t2zliNJUEekKU s/x6y9anxf31XntmVNMba+IHHMYBAfNIqt2btHqVToNZsp90nneQx88WmXs1LZmVF8756+8F4YQmV ag1DJ9+0TmWsgThsct+8aNLBlvH0FIxofBZnf5IbT0rPn2dy1CURt2qK75JPK9D55ZQDK5E+pbov5 311Xit3+ZP18tZ0A3UqoiCbRj+ysESCM8RgkPUbCXRkhQK+vLXmLSis20+GYgSJx5T5NHf7YWZF1z OCUclV3N76EfXJ8g/DJPHiXksOKjYlCyIwU9A3577fyK2fG6rl0t6V6LpBIEhgn88JoyaaaaG14IK MzGLDGxQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u26Df-00000003fgB-3aaD; Tue, 08 Apr 2025 10:30:15 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u25e0-00000003WXc-3nz5; Tue, 08 Apr 2025 09:53:26 +0000 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 66F6A22FA; Tue, 8 Apr 2025 02:53:25 -0700 (PDT) Received: from e123572-lin.arm.com (e123572-lin.cambridge.arm.com [10.1.194.54]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 27BC83F6A8; Tue, 8 Apr 2025 02:53:20 -0700 (PDT) From: Kevin Brodsky To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Kevin Brodsky , Albert Ou , Andreas Larsson , Andrew Morton , Catalin Marinas , Dave Hansen , "David S. Miller" , Geert Uytterhoeven , Linus Walleij , Madhavan Srinivasan , Mark Rutland , Matthew Wilcox , Michael Ellerman , "Mike Rapoport (IBM)" , Palmer Dabbelt , Paul Walmsley , Peter Zijlstra , Qi Zheng , Ryan Roberts , Will Deacon , Yang Shi , linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-openrisc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, x86@kernel.org Subject: [PATCH v2 03/12] mm: Call ctor/dtor for kernel PTEs Date: Tue, 8 Apr 2025 10:52:13 +0100 Message-ID: <20250408095222.860601-4-kevin.brodsky@arm.com> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20250408095222.860601-1-kevin.brodsky@arm.com> References: <20250408095222.860601-1-kevin.brodsky@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250408_025325_035828_D8D9081B X-CRM114-Status: GOOD ( 19.23 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Since [1], constructors/destructors are expected to be called for all page table pages, at all levels and for both user and kernel pgtables. There is however one glaring exception: kernel PTEs are managed via separate helpers (pte_alloc_kernel/pte_free_kernel), which do not call the [cd]tor, at least not in the generic implementation. The most obvious reason for this anomaly is that init_mm is special-cased not to use split page table locks. As a result calling ptlock_init() for PTEs associated with init_mm would be wasteful, potentially resulting in dynamic memory allocation. However, pgtable [cd]tors perform other actions - currently related to accounting/statistics, and potentially more functionally significant in the future. Now that pagetable_pte_ctor() is passed the associated mm, we can make it skip the call to ptlock_init() for init_mm; this allows us to call the ctor from pte_alloc_one_kernel() too. This is matched by a call to the pgtable destructor in pte_free_kernel(); no special-casing is needed on that path, as ptlock_free() is already called unconditionally. (ptlock_free() is a no-op unless a ptlock was allocated for the given PTP.) This patch ensures that all architectures that rely on call the [cd]tor for kernel PTEs. pte_free_kernel() cannot be overridden so changing the generic implementation is sufficient. pte_alloc_one_kernel() can be overridden using __HAVE_ARCH_PTE_ALLOC_ONE_KERNEL, and a few architectures implement it by calling the page allocator directly. We amend those so that they call the generic __pte_alloc_one_kernel() instead, if possible, ensuring that the ctor is called. A few architectures do not use ; those will be taken care of separately. [1] https://lore.kernel.org/linux-mm/20250103184415.2744423-1-kevin.brodsky@arm.com/ Signed-off-by: Kevin Brodsky --- arch/csky/include/asm/pgalloc.h | 2 +- arch/microblaze/mm/pgtable.c | 2 +- arch/openrisc/mm/ioremap.c | 2 +- include/asm-generic/pgalloc.h | 7 ++++++- include/linux/mm.h | 2 +- 5 files changed, 10 insertions(+), 5 deletions(-) diff --git a/arch/csky/include/asm/pgalloc.h b/arch/csky/include/asm/pgalloc.h index 11055c574968..9ed2b15ffd94 100644 --- a/arch/csky/include/asm/pgalloc.h +++ b/arch/csky/include/asm/pgalloc.h @@ -29,7 +29,7 @@ static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm) pte_t *pte; unsigned long i; - pte = (pte_t *) __get_free_page(GFP_KERNEL); + pte = __pte_alloc_one_kernel(mm); if (!pte) return NULL; diff --git a/arch/microblaze/mm/pgtable.c b/arch/microblaze/mm/pgtable.c index 9f73265aad4e..e96dd1b7aba4 100644 --- a/arch/microblaze/mm/pgtable.c +++ b/arch/microblaze/mm/pgtable.c @@ -245,7 +245,7 @@ unsigned long iopa(unsigned long addr) __ref pte_t *pte_alloc_one_kernel(struct mm_struct *mm) { if (mem_init_done) - return (pte_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO); + return __pte_alloc_one_kernel(mm); else return memblock_alloc_try_nid(PAGE_SIZE, PAGE_SIZE, MEMBLOCK_LOW_LIMIT, diff --git a/arch/openrisc/mm/ioremap.c b/arch/openrisc/mm/ioremap.c index 8e63e86251ca..3b352f97fecb 100644 --- a/arch/openrisc/mm/ioremap.c +++ b/arch/openrisc/mm/ioremap.c @@ -36,7 +36,7 @@ pte_t __ref *pte_alloc_one_kernel(struct mm_struct *mm) pte_t *pte; if (likely(mem_init_done)) { - pte = (pte_t *)get_zeroed_page(GFP_KERNEL); + pte = __pte_alloc_one_kernel(mm); } else { pte = memblock_alloc_or_panic(PAGE_SIZE, PAGE_SIZE); } diff --git a/include/asm-generic/pgalloc.h b/include/asm-generic/pgalloc.h index e164ca66f0f6..3c8ec3bfea44 100644 --- a/include/asm-generic/pgalloc.h +++ b/include/asm-generic/pgalloc.h @@ -23,6 +23,11 @@ static inline pte_t *__pte_alloc_one_kernel_noprof(struct mm_struct *mm) if (!ptdesc) return NULL; + if (!pagetable_pte_ctor(mm, ptdesc)) { + pagetable_free(ptdesc); + return NULL; + } + return ptdesc_address(ptdesc); } #define __pte_alloc_one_kernel(...) alloc_hooks(__pte_alloc_one_kernel_noprof(__VA_ARGS__)) @@ -48,7 +53,7 @@ static inline pte_t *pte_alloc_one_kernel_noprof(struct mm_struct *mm) */ static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte) { - pagetable_free(virt_to_ptdesc(pte)); + pagetable_dtor_free(virt_to_ptdesc(pte)); } /** diff --git a/include/linux/mm.h b/include/linux/mm.h index f9b793cce2c1..3f48e449574a 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3103,7 +3103,7 @@ static inline void pagetable_dtor_free(struct ptdesc *ptdesc) static inline bool pagetable_pte_ctor(struct mm_struct *mm, struct ptdesc *ptdesc) { - if (!ptlock_init(ptdesc)) + if (mm != &init_mm && !ptlock_init(ptdesc)) return false; __pagetable_ctor(ptdesc); return true; From patchwork Tue Apr 8 09:52:14 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Brodsky X-Patchwork-Id: 14042692 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2384EC3600C for ; 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Tue, 08 Apr 2025 10:32:08 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u25e5-00000003WZS-37cx; Tue, 08 Apr 2025 09:53:30 +0000 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 211432308; Tue, 8 Apr 2025 02:53:30 -0700 (PDT) Received: from e123572-lin.arm.com (e123572-lin.cambridge.arm.com [10.1.194.54]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id D3DDB3F6A8; Tue, 8 Apr 2025 02:53:24 -0700 (PDT) From: Kevin Brodsky To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Kevin Brodsky , Albert Ou , Andreas Larsson , Andrew Morton , Catalin Marinas , Dave Hansen , "David S. Miller" , Geert Uytterhoeven , Linus Walleij , Madhavan Srinivasan , Mark Rutland , Matthew Wilcox , Michael Ellerman , "Mike Rapoport (IBM)" , Palmer Dabbelt , Paul Walmsley , Peter Zijlstra , Qi Zheng , Ryan Roberts , Will Deacon , Yang Shi , linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-openrisc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, x86@kernel.org Subject: [PATCH v2 04/12] m68k: mm: Call ctor/dtor for kernel PTEs Date: Tue, 8 Apr 2025 10:52:14 +0100 Message-ID: <20250408095222.860601-5-kevin.brodsky@arm.com> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20250408095222.860601-1-kevin.brodsky@arm.com> References: <20250408095222.860601-1-kevin.brodsky@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250408_025329_825663_190200BD X-CRM114-Status: GOOD ( 11.00 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The generic implementation of pte_{alloc_one,free}_kernel now calls the [cd]tor. Align the m68k/ColdFire implementation of those functions by calling the [cd]tor explicitly. Signed-off-by: Kevin Brodsky --- arch/m68k/include/asm/mcf_pgalloc.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/m68k/include/asm/mcf_pgalloc.h b/arch/m68k/include/asm/mcf_pgalloc.h index 465a71101b7d..fc5454d37da3 100644 --- a/arch/m68k/include/asm/mcf_pgalloc.h +++ b/arch/m68k/include/asm/mcf_pgalloc.h @@ -7,7 +7,7 @@ static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte) { - pagetable_free(virt_to_ptdesc(pte)); + pagetable_dtor_free(virt_to_ptdesc(pte)); } extern const char bad_pmd_string[]; @@ -19,6 +19,10 @@ static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm) if (!ptdesc) return NULL; + if (!pagetable_pte_ctor(mm, ptdesc)) { + pagetable_free(ptdesc); + return NULL; + } return ptdesc_address(ptdesc); } From patchwork Tue Apr 8 09:52:15 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Brodsky X-Patchwork-Id: 14042712 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8AAF8C369A1 for ; Tue, 8 Apr 2025 10:34:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=/BkpJ0cTKq4ChrXalGvhAQpS6e0Bp2XA+877e60Q9Ds=; b=ypH9rh7BG0HRIai4m+sDU4bESB ChpKiVAqpq9xrhKS3t92ZSWeupz3aGabmS3hfBwnP40LhmxkkEIc5Kbh1pKaUPy+GXokHP/xX9ffH qVm99Jizvee58Dfy70gP0a7UorXDvCIUl04MEVzHOOU6DgJW7Foy830ElCG2C89P9lYBqYo00+4CW 0ybImLLp3FmiZ7NMh5g+sOHDDSAhaEBxUqT54wX8UOEC15XLF2NPjtj//Revnl2TVPP7cD9I+6U4C MqX7d1Xklmo1e9Ni2XVdBzQc9dm0chGHdXmTEBcH6qIlpJN6uInc4GbX2qfjd5maZmtWVjzHUdek5 VQndPTeA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u26HG-00000003gaU-3Ysd; Tue, 08 Apr 2025 10:33:58 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u25eA-00000003WbJ-1Hxy; Tue, 08 Apr 2025 09:53:36 +0000 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 CCE4822FC; Tue, 8 Apr 2025 02:53:34 -0700 (PDT) Received: from e123572-lin.arm.com (e123572-lin.cambridge.arm.com [10.1.194.54]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 8D5873F6A8; Tue, 8 Apr 2025 02:53:29 -0700 (PDT) From: Kevin Brodsky To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Kevin Brodsky , Albert Ou , Andreas Larsson , Andrew Morton , Catalin Marinas , Dave Hansen , "David S. Miller" , Geert Uytterhoeven , Linus Walleij , Madhavan Srinivasan , Mark Rutland , Matthew Wilcox , Michael Ellerman , "Mike Rapoport (IBM)" , Palmer Dabbelt , Paul Walmsley , Peter Zijlstra , Qi Zheng , Ryan Roberts , Will Deacon , Yang Shi , linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-openrisc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, x86@kernel.org Subject: [PATCH v2 05/12] powerpc: mm: Call ctor/dtor for kernel PTEs Date: Tue, 8 Apr 2025 10:52:15 +0100 Message-ID: <20250408095222.860601-6-kevin.brodsky@arm.com> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20250408095222.860601-1-kevin.brodsky@arm.com> References: <20250408095222.860601-1-kevin.brodsky@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250408_025334_477372_1471B2BC X-CRM114-Status: GOOD ( 13.11 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The generic implementation of pte_{alloc_one,free}_kernel now calls the [cd]tor, without initialising the ptlock needlessly as pagetable_pte_ctor() skips it for init_mm. On powerpc, all functions related to PTE allocation are implemented by common helpers, which are passed a boolean to differentiate user from kernel pgtables. This patch aligns the powerpc implementation with the generic one by calling pagetable_pte_[cd]tor() unconditionally in those helpers. Signed-off-by: Kevin Brodsky --- arch/powerpc/mm/pgtable-frag.c | 30 +++++++++++++----------------- 1 file changed, 13 insertions(+), 17 deletions(-) diff --git a/arch/powerpc/mm/pgtable-frag.c b/arch/powerpc/mm/pgtable-frag.c index 387e9b1fe12c..77e55eac16e4 100644 --- a/arch/powerpc/mm/pgtable-frag.c +++ b/arch/powerpc/mm/pgtable-frag.c @@ -56,19 +56,17 @@ static pte_t *__alloc_for_ptecache(struct mm_struct *mm, int kernel) { void *ret = NULL; struct ptdesc *ptdesc; + gfp_t gfp = PGALLOC_GFP; - if (!kernel) { - ptdesc = pagetable_alloc(PGALLOC_GFP | __GFP_ACCOUNT, 0); - if (!ptdesc) - return NULL; - if (!pagetable_pte_ctor(mm, ptdesc)) { - pagetable_free(ptdesc); - return NULL; - } - } else { - ptdesc = pagetable_alloc(PGALLOC_GFP, 0); - if (!ptdesc) - return NULL; + if (!kernel) + gfp |= __GFP_ACCOUNT; + + ptdesc = pagetable_alloc(gfp, 0); + if (!ptdesc) + return NULL; + if (!pagetable_pte_ctor(mm, ptdesc)) { + pagetable_free(ptdesc); + return NULL; } atomic_set(&ptdesc->pt_frag_refcount, 1); @@ -124,12 +122,10 @@ void pte_fragment_free(unsigned long *table, int kernel) BUG_ON(atomic_read(&ptdesc->pt_frag_refcount) <= 0); if (atomic_dec_and_test(&ptdesc->pt_frag_refcount)) { - if (kernel) - pagetable_free(ptdesc); - else if (folio_test_clear_active(ptdesc_folio(ptdesc))) - call_rcu(&ptdesc->pt_rcu_head, pte_free_now); - else + if (kernel || !folio_test_clear_active(ptdesc_folio(ptdesc))) pte_free_now(&ptdesc->pt_rcu_head); + else + call_rcu(&ptdesc->pt_rcu_head, pte_free_now); } } From patchwork Tue Apr 8 09:52:16 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Brodsky X-Patchwork-Id: 14042904 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A1134C369A4 for ; Tue, 8 Apr 2025 11:42:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=mhR2Iq+beAhq3GZKKAxztcVBqkxIucxufOP5/zFYWuY=; b=HsBQdMcZKewjjup7cX+1F5TN6Y RuieGPjHujA7g3FNw+dcx43L3wh5f0ukIlTwLPFS0yRakS5/Y+m0Qnbh3XlYwa9XX1PtA19NnF6gF bDJdXIgFIGMk38NkotHYNIdqr31jYHdQppDJAwUkg7eDglZwoxF5K3VTDTZBMXPbDdPUDW9MM1E8t VoHylzHknvC1bEkl9BSO4RpWabazz4VRRI6sqky2K1jUy/rEwpCvwO5mYYot/7Ot1X6veIZ6FBEEb xLVshJgd4KMncUgO5YdMO9zFqXEkA58HxfCqj0C1NkEYfdoy2Xyq2NxLQRuaEiJfkTRpmBvjO2CqX M8wGz+CQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u27Lp-00000003snZ-0eg5; Tue, 08 Apr 2025 11:42:45 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u25eF-00000003Wef-0Ieb; Tue, 08 Apr 2025 09:53:40 +0000 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 861E82309; Tue, 8 Apr 2025 02:53:39 -0700 (PDT) Received: from e123572-lin.arm.com (e123572-lin.cambridge.arm.com [10.1.194.54]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 4566F3F6A8; Tue, 8 Apr 2025 02:53:34 -0700 (PDT) From: Kevin Brodsky To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Kevin Brodsky , Albert Ou , Andreas Larsson , Andrew Morton , Catalin Marinas , Dave Hansen , "David S. Miller" , Geert Uytterhoeven , Linus Walleij , Madhavan Srinivasan , Mark Rutland , Matthew Wilcox , Michael Ellerman , "Mike Rapoport (IBM)" , Palmer Dabbelt , Paul Walmsley , Peter Zijlstra , Qi Zheng , Ryan Roberts , Will Deacon , Yang Shi , linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-openrisc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, x86@kernel.org Subject: [PATCH v2 06/12] sparc64: mm: Call ctor/dtor for kernel PTEs Date: Tue, 8 Apr 2025 10:52:16 +0100 Message-ID: <20250408095222.860601-7-kevin.brodsky@arm.com> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20250408095222.860601-1-kevin.brodsky@arm.com> References: <20250408095222.860601-1-kevin.brodsky@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250408_025339_144426_5AE8919F X-CRM114-Status: GOOD ( 12.42 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The generic implementation of pte_{alloc_one,free}_kernel now calls the [cd]tor, without initialising the ptlock needlessly as pagetable_pte_ctor() skips it for init_mm. Align sparc64 with the generic implementation by ensuring pagetable_pte_[cd]tor() are called for kernel PTEs. As a result the kernel and user alloc/free functions have the same implementation, and since pgtable_t is defined as pte_t *, we can have both call a common helper. Signed-off-by: Kevin Brodsky --- arch/sparc/mm/init_64.c | 27 +++++++++++++-------------- 1 file changed, 13 insertions(+), 14 deletions(-) diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c index 5c8eabda1d17..25ae4c897aae 100644 --- a/arch/sparc/mm/init_64.c +++ b/arch/sparc/mm/init_64.c @@ -2878,18 +2878,7 @@ void __flush_tlb_all(void) : : "r" (pstate)); } -pte_t *pte_alloc_one_kernel(struct mm_struct *mm) -{ - struct page *page = alloc_page(GFP_KERNEL | __GFP_ZERO); - pte_t *pte = NULL; - - if (page) - pte = (pte_t *) page_address(page); - - return pte; -} - -pgtable_t pte_alloc_one(struct mm_struct *mm) +static pte_t *__pte_alloc_one(struct mm_struct *mm) { struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL | __GFP_ZERO, 0); @@ -2902,9 +2891,14 @@ pgtable_t pte_alloc_one(struct mm_struct *mm) return ptdesc_address(ptdesc); } -void pte_free_kernel(struct mm_struct *mm, pte_t *pte) +pte_t *pte_alloc_one_kernel(struct mm_struct *mm) { - free_page((unsigned long)pte); + return __pte_alloc_one(mm); +} + +pgtable_t pte_alloc_one(struct mm_struct *mm) +{ + return __pte_alloc_one(mm); } static void __pte_free(pgtable_t pte) @@ -2915,6 +2909,11 @@ static void __pte_free(pgtable_t pte) pagetable_free(ptdesc); } +void pte_free_kernel(struct mm_struct *mm, pte_t *pte) +{ + __pte_free(pte); +} + void pte_free(struct mm_struct *mm, pgtable_t pte) { __pte_free(pte); From patchwork Tue Apr 8 09:52:17 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Brodsky X-Patchwork-Id: 14042713 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 9D119C369A1 for ; Tue, 8 Apr 2025 10:37:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=AoW5uPcncPp3axMC3OLXSZhaQ2vhQ+ldUmkYdrG/FME=; b=BkGGXdVR/FaLh82WpUGi1Kchvn fryD1XyALml3zcB/AJqjhqenAD9E5w5XeJWu2A4osw/J6LkLPGg+0k/tsPk6pYRiVE59FBqL3L/5K D5sNcXB1n/cylhJmJB0kqPw0GvPiV++P5g4qFDf8Dk9ZCufMVTst1j9AKjCXDuwbHxAQOKnIdO9vv 5PiMUKlGmpGJjEJf6TYAW4C750Vwj9g9l433YlYD/UxjaYzPcWYgi50Rwd5WnozG+yKYA+hdqjyUT Kud7HrngEU2gGj91teNcGI3tKV1Vc1ekg2LUArM7sjtPUEQZK0nmdaTbqC7I6KhSNyqs4kGsPjkSc u4f3UX6Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u26Ks-00000003hEy-2DBl; Tue, 08 Apr 2025 10:37:42 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u25eJ-00000003Wh3-33AO; Tue, 08 Apr 2025 09:53:45 +0000 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 3EB2B2328; Tue, 8 Apr 2025 02:53:44 -0700 (PDT) Received: from e123572-lin.arm.com (e123572-lin.cambridge.arm.com [10.1.194.54]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id F29D83F6A8; Tue, 8 Apr 2025 02:53:38 -0700 (PDT) From: Kevin Brodsky To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Kevin Brodsky , Albert Ou , Andreas Larsson , Andrew Morton , Catalin Marinas , Dave Hansen , "David S. Miller" , Geert Uytterhoeven , Linus Walleij , Madhavan Srinivasan , Mark Rutland , Matthew Wilcox , Michael Ellerman , "Mike Rapoport (IBM)" , Palmer Dabbelt , Paul Walmsley , Peter Zijlstra , Qi Zheng , Ryan Roberts , Will Deacon , Yang Shi , linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-openrisc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, x86@kernel.org Subject: [PATCH v2 07/12] mm: Skip ptlock_init() for kernel PMDs Date: Tue, 8 Apr 2025 10:52:17 +0100 Message-ID: <20250408095222.860601-8-kevin.brodsky@arm.com> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20250408095222.860601-1-kevin.brodsky@arm.com> References: <20250408095222.860601-1-kevin.brodsky@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250408_025343_817713_5953F9AF X-CRM114-Status: GOOD ( 14.43 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Split page table locks are not used for pgtables associated to init_mm, at any level. pte_alloc_kernel() does not call ptlock_init() as a result. There is however no separate alloc/free functions for kernel PMDs, and pmd_ptlock_init() is called unconditionally. When ALLOC_SPLIT_PTLOCKS is true (e.g. 32-bit architectures or if CONFIG_PREEMPT_RT is selected), this results in unnecessary dynamic memory allocation every time a kernel PMD is allocated. Now that pagetable_pmd_ctor() is passed the associated mm, we can easily remove this overhead by skipping pmd_ptlock_init() if the pgtable is associated to init_mm. No special-casing is needed on the dtor path, as ptlock_free() is already called unconditionally for all levels. (ptlock_free() is a no-op unless a ptlock was allocated for the given PTP.) Signed-off-by: Kevin Brodsky --- include/linux/mm.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 3f48e449574a..ef420f4dc72c 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3210,7 +3210,7 @@ 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 (!pmd_ptlock_init(ptdesc)) + if (mm != &init_mm && !pmd_ptlock_init(ptdesc)) return false; ptdesc_pmd_pts_init(ptdesc); __pagetable_ctor(ptdesc); From patchwork Tue Apr 8 09:52:18 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Brodsky X-Patchwork-Id: 14042766 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D7FEBC369A1 for ; Tue, 8 Apr 2025 10:39:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=+0pYQ1qH+UpfJYLoe9vNgfctFN5Ww4sCZmrF9jkxtoc=; b=kVNRnLAAbBXGKbi+bTH4hGLQvN 4Z6iRsnE+MBrrm3G77WXL+i2jSEOjV8Wrws0V4v4KEV5KQplfN2vF87KjNpiLM057UMbJcn/uU2kW q/sG6ObCJd7aqkVI3xQrg+lAAay2EuM/5WehY2TLaPu9ZS80kO+KhlTYJP1lIDgpDjsVC+LMQd2w2 HVLDOu7Zr+zVWAps5OMZPVKcutYwgTwds3ZxKoFf9/fh3BJcZ6eJsVjoIl30ZOFZf4pQyXiCX3NH/ Q7kk/nRLqJu7Kuln5f3fbt+VbsWH9QTdCpHY6rkayj01geJSvHl1I9faId3Y/Q0h9BdYaOHpqfYK7 WvlRHhgg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u26Mf-00000003hhb-3aP5; Tue, 08 Apr 2025 10:39:33 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u25eO-00000003Wiq-1uE3; Tue, 08 Apr 2025 09:53:49 +0000 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 EC0D71688; Tue, 8 Apr 2025 02:53:48 -0700 (PDT) Received: from e123572-lin.arm.com (e123572-lin.cambridge.arm.com [10.1.194.54]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id ABBF53F6A8; Tue, 8 Apr 2025 02:53:43 -0700 (PDT) From: Kevin Brodsky To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Kevin Brodsky , Albert Ou , Andreas Larsson , Andrew Morton , Catalin Marinas , Dave Hansen , "David S. Miller" , Geert Uytterhoeven , Linus Walleij , Madhavan Srinivasan , Mark Rutland , Matthew Wilcox , Michael Ellerman , "Mike Rapoport (IBM)" , Palmer Dabbelt , Paul Walmsley , Peter Zijlstra , Qi Zheng , Ryan Roberts , Will Deacon , Yang Shi , linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-openrisc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, x86@kernel.org Subject: [PATCH v2 08/12] arm64: mm: Use enum to identify pgtable level instead of *_SHIFT Date: Tue, 8 Apr 2025 10:52:18 +0100 Message-ID: <20250408095222.860601-9-kevin.brodsky@arm.com> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20250408095222.860601-1-kevin.brodsky@arm.com> References: <20250408095222.860601-1-kevin.brodsky@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250408_025348_586630_47224507 X-CRM114-Status: GOOD ( 16.75 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Commit 90292aca9854 ("arm64: mm: use appropriate ctors for page tables") introduced pgtable ctor calls in pgd_pgtable_alloc(). To identify the pgtable level and call the appropriate ctor, the *_SHIFT value associated with the pgtable level is used. However, those values do not unambiguously identify a level, because if a given level is folded, the *_SHIFT value will be equal to that of the upper level (e.g. PMD_SHIFT == PUD_SHIFT if PMD is folded). As things stand, there is probably not much damaged done by calling the ctor for a different level, and ARCH_ENABLE_SPLIT_PMD_PTLOCK is only selected if PMD isn't folded (so we don't needlessly initialise pmd_ptlock). Still, this is pretty confusing, and it would get even more confusing when adding ctor calls for the remaining levels. Let's simplify all this by using an enum to identify the pgtable level instead; this way folding becomes irrelevant. This is inspired by one of the m68k pgtable allocators (arch/m68k/include/asm/motorola_pgalloc.h). Signed-off-by: Kevin Brodsky --- arch/arm64/mm/mmu.c | 54 +++++++++++++++++++++++++++------------------ 1 file changed, 33 insertions(+), 21 deletions(-) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 8c5c471cfb06..eca324b3a6fc 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -46,6 +46,13 @@ #define NO_CONT_MAPPINGS BIT(1) #define NO_EXEC_MAPPINGS BIT(2) /* assumes FEAT_HPDS is not used */ +enum pgtable_type { + TABLE_PTE, + TABLE_PMD, + TABLE_PUD, + TABLE_P4D, +}; + u64 kimage_voffset __ro_after_init; EXPORT_SYMBOL(kimage_voffset); @@ -107,7 +114,7 @@ pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, } EXPORT_SYMBOL(phys_mem_access_prot); -static phys_addr_t __init early_pgtable_alloc(int shift) +static phys_addr_t __init early_pgtable_alloc(enum pgtable_type pgtable_type) { phys_addr_t phys; @@ -192,7 +199,7 @@ static void init_pte(pte_t *ptep, unsigned long addr, unsigned long end, static void alloc_init_cont_pte(pmd_t *pmdp, unsigned long addr, unsigned long end, phys_addr_t phys, pgprot_t prot, - phys_addr_t (*pgtable_alloc)(int), + phys_addr_t (*pgtable_alloc)(enum pgtable_type), int flags) { unsigned long next; @@ -207,7 +214,7 @@ static void alloc_init_cont_pte(pmd_t *pmdp, unsigned long addr, if (flags & NO_EXEC_MAPPINGS) pmdval |= PMD_TABLE_PXN; BUG_ON(!pgtable_alloc); - pte_phys = pgtable_alloc(PAGE_SHIFT); + pte_phys = pgtable_alloc(TABLE_PTE); ptep = pte_set_fixmap(pte_phys); init_clear_pgtable(ptep); ptep += pte_index(addr); @@ -243,7 +250,7 @@ static void alloc_init_cont_pte(pmd_t *pmdp, unsigned long addr, static void init_pmd(pmd_t *pmdp, unsigned long addr, unsigned long end, phys_addr_t phys, pgprot_t prot, - phys_addr_t (*pgtable_alloc)(int), int flags) + phys_addr_t (*pgtable_alloc)(enum pgtable_type), int flags) { unsigned long next; @@ -277,7 +284,8 @@ static void init_pmd(pmd_t *pmdp, unsigned long addr, unsigned long end, static void alloc_init_cont_pmd(pud_t *pudp, unsigned long addr, unsigned long end, phys_addr_t phys, pgprot_t prot, - phys_addr_t (*pgtable_alloc)(int), int flags) + phys_addr_t (*pgtable_alloc)(enum pgtable_type), + int flags) { unsigned long next; pud_t pud = READ_ONCE(*pudp); @@ -294,7 +302,7 @@ static void alloc_init_cont_pmd(pud_t *pudp, unsigned long addr, if (flags & NO_EXEC_MAPPINGS) pudval |= PUD_TABLE_PXN; BUG_ON(!pgtable_alloc); - pmd_phys = pgtable_alloc(PMD_SHIFT); + pmd_phys = pgtable_alloc(TABLE_PMD); pmdp = pmd_set_fixmap(pmd_phys); init_clear_pgtable(pmdp); pmdp += pmd_index(addr); @@ -325,7 +333,7 @@ static void alloc_init_cont_pmd(pud_t *pudp, unsigned long addr, static void alloc_init_pud(p4d_t *p4dp, unsigned long addr, unsigned long end, phys_addr_t phys, pgprot_t prot, - phys_addr_t (*pgtable_alloc)(int), + phys_addr_t (*pgtable_alloc)(enum pgtable_type), int flags) { unsigned long next; @@ -339,7 +347,7 @@ static void alloc_init_pud(p4d_t *p4dp, unsigned long addr, unsigned long end, if (flags & NO_EXEC_MAPPINGS) p4dval |= P4D_TABLE_PXN; BUG_ON(!pgtable_alloc); - pud_phys = pgtable_alloc(PUD_SHIFT); + pud_phys = pgtable_alloc(TABLE_PUD); pudp = pud_set_fixmap(pud_phys); init_clear_pgtable(pudp); pudp += pud_index(addr); @@ -383,7 +391,7 @@ static void alloc_init_pud(p4d_t *p4dp, unsigned long addr, unsigned long end, static void alloc_init_p4d(pgd_t *pgdp, unsigned long addr, unsigned long end, phys_addr_t phys, pgprot_t prot, - phys_addr_t (*pgtable_alloc)(int), + phys_addr_t (*pgtable_alloc)(enum pgtable_type), int flags) { unsigned long next; @@ -397,7 +405,7 @@ static void alloc_init_p4d(pgd_t *pgdp, unsigned long addr, unsigned long end, if (flags & NO_EXEC_MAPPINGS) pgdval |= PGD_TABLE_PXN; BUG_ON(!pgtable_alloc); - p4d_phys = pgtable_alloc(P4D_SHIFT); + p4d_phys = pgtable_alloc(TABLE_P4D); p4dp = p4d_set_fixmap(p4d_phys); init_clear_pgtable(p4dp); p4dp += p4d_index(addr); @@ -427,7 +435,7 @@ static void alloc_init_p4d(pgd_t *pgdp, unsigned long addr, unsigned long end, static void __create_pgd_mapping_locked(pgd_t *pgdir, phys_addr_t phys, unsigned long virt, phys_addr_t size, pgprot_t prot, - phys_addr_t (*pgtable_alloc)(int), + phys_addr_t (*pgtable_alloc)(enum pgtable_type), int flags) { unsigned long addr, end, next; @@ -455,7 +463,7 @@ static void __create_pgd_mapping_locked(pgd_t *pgdir, phys_addr_t phys, static void __create_pgd_mapping(pgd_t *pgdir, phys_addr_t phys, unsigned long virt, phys_addr_t size, pgprot_t prot, - phys_addr_t (*pgtable_alloc)(int), + phys_addr_t (*pgtable_alloc)(enum pgtable_type), int flags) { mutex_lock(&fixmap_lock); @@ -468,10 +476,11 @@ static void __create_pgd_mapping(pgd_t *pgdir, phys_addr_t phys, extern __alias(__create_pgd_mapping_locked) void create_kpti_ng_temp_pgd(pgd_t *pgdir, phys_addr_t phys, unsigned long virt, phys_addr_t size, pgprot_t prot, - phys_addr_t (*pgtable_alloc)(int), int flags); + phys_addr_t (*pgtable_alloc)(enum pgtable_type), + int flags); #endif -static phys_addr_t __pgd_pgtable_alloc(int shift) +static phys_addr_t __pgd_pgtable_alloc(enum pgtable_type pgtable_type) { /* Page is zeroed by init_clear_pgtable() so don't duplicate effort. */ void *ptr = (void *)__get_free_page(GFP_PGTABLE_KERNEL & ~__GFP_ZERO); @@ -480,23 +489,26 @@ static phys_addr_t __pgd_pgtable_alloc(int shift) return __pa(ptr); } -static phys_addr_t pgd_pgtable_alloc(int shift) +static phys_addr_t pgd_pgtable_alloc(enum pgtable_type pgtable_type) { - phys_addr_t pa = __pgd_pgtable_alloc(shift); + phys_addr_t pa = __pgd_pgtable_alloc(pgtable_type); struct ptdesc *ptdesc = page_ptdesc(phys_to_page(pa)); /* * Call proper page table ctor in case later we need to * call core mm functions like apply_to_page_range() on * this pre-allocated page table. - * - * We don't select ARCH_ENABLE_SPLIT_PMD_PTLOCK if pmd is - * folded, and if so pagetable_pte_ctor() becomes nop. */ - if (shift == PAGE_SHIFT) + switch (pgtable_type) { + case TABLE_PTE: BUG_ON(!pagetable_pte_ctor(NULL, ptdesc)); - else if (shift == PMD_SHIFT) + break; + case TABLE_PMD: BUG_ON(!pagetable_pmd_ctor(NULL, ptdesc)); + break; + default: + break; + } return pa; } From patchwork Tue Apr 8 09:52:19 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Brodsky X-Patchwork-Id: 14042767 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 06E60C369A4 for ; 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Tue, 08 Apr 2025 10:41:26 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u25eT-00000003WlY-0bak; Tue, 08 Apr 2025 09:53:55 +0000 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 A4D9F1691; Tue, 8 Apr 2025 02:53:53 -0700 (PDT) Received: from e123572-lin.arm.com (e123572-lin.cambridge.arm.com [10.1.194.54]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 64C983F6A8; Tue, 8 Apr 2025 02:53:48 -0700 (PDT) From: Kevin Brodsky To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Kevin Brodsky , Albert Ou , Andreas Larsson , Andrew Morton , Catalin Marinas , Dave Hansen , "David S. Miller" , Geert Uytterhoeven , Linus Walleij , Madhavan Srinivasan , Mark Rutland , Matthew Wilcox , Michael Ellerman , "Mike Rapoport (IBM)" , Palmer Dabbelt , Paul Walmsley , Peter Zijlstra , Qi Zheng , Ryan Roberts , Will Deacon , Yang Shi , linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-openrisc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, x86@kernel.org Subject: [PATCH v2 09/12] arm64: mm: Always call PTE/PMD ctor in __create_pgd_mapping() Date: Tue, 8 Apr 2025 10:52:19 +0100 Message-ID: <20250408095222.860601-10-kevin.brodsky@arm.com> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20250408095222.860601-1-kevin.brodsky@arm.com> References: <20250408095222.860601-1-kevin.brodsky@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250408_025353_311280_DA0F870D X-CRM114-Status: GOOD ( 23.31 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org TL;DR: always call the PTE/PMD ctor, passing the appropriate mm to skip ptlock_init() if unneeded. __create_pgd_mapping() is used for creating different kinds of mappings, and may allocate page table pages if passed an allocator callback. There are currently three such cases: 1. create_pgd_mapping(), which is used to create the EFI mapping 2. arch_add_memory() 3. map_entry_trampoline() 1. uses pgd_pgtable_alloc() as allocator callback, which calls the PTE/PMD ctor, while 2. and 3. use __pgd_pgtable_alloc(), which does not. The rationale is most likely that pgtables associated with init_mm do not make use of split page table locks, and it is therefore unnecessary to initialise them by calling the ctor. 2. operates on swapper_pg_dir so the allocated pgtables are clearly associated with init_mm, this is arguably the case for 3. too (the trampoline mapping is never modified so ptlocks are anyway irrelevant). 1. corresponds to efi_mm so ptlocks need to be initialised in that case. We are now moving towards calling the ctor for all page tables, even those associated with init_mm. pagetable_{pte,pmd}_ctor() have become aware of the associated mm so that the ptlock initialisation can be skipped for init_mm. This patch therefore amends the allocator callbacks so that the PTE/PMD ctor are always called, with an appropriate mm pointer to avoid unnecessary ptlock overhead. Modifying the prototype of the allocator callbacks to take the mm and propagating that pointer all the way down would be pretty invasive. Instead: * __pgd_pgtable_alloc() (cases 2. and 3. above) is replaced with pgd_pgtable_alloc_init_mm(), resulting in the ctors being called with &init_mm. This is the main functional change in this patch; the ptlock still isn't initialised, but other ctor actions (e.g. accounting-related) are now carried out for those allocated pgtables. * pgd_pgtable_alloc() (case 1. above) is replaced with pgd_pgtable_alloc_special_mm(), resulting in the ctors being called with NULL as mm. No functional change here; NULL essentially means "not init_mm", and the ptlock is still initialised. __pgd_pgtable_alloc() is now the common implementation of those two helpers. While at it we switch it to using pagetable_alloc() like standard pgtable allocator functions and remove the comment regarding ctor calls (ctors are now always expected to be called). Signed-off-by: Kevin Brodsky --- arch/arm64/mm/mmu.c | 43 +++++++++++++++++++++++-------------------- 1 file changed, 23 insertions(+), 20 deletions(-) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index eca324b3a6fc..51cfc891f6a1 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -480,31 +480,22 @@ void create_kpti_ng_temp_pgd(pgd_t *pgdir, phys_addr_t phys, unsigned long virt, int flags); #endif -static phys_addr_t __pgd_pgtable_alloc(enum pgtable_type pgtable_type) +static phys_addr_t __pgd_pgtable_alloc(struct mm_struct *mm, + enum pgtable_type pgtable_type) { /* Page is zeroed by init_clear_pgtable() so don't duplicate effort. */ - void *ptr = (void *)__get_free_page(GFP_PGTABLE_KERNEL & ~__GFP_ZERO); + struct ptdesc *ptdesc = pagetable_alloc(GFP_PGTABLE_KERNEL & ~__GFP_ZERO, 0); + phys_addr_t pa; - BUG_ON(!ptr); - return __pa(ptr); -} - -static phys_addr_t pgd_pgtable_alloc(enum pgtable_type pgtable_type) -{ - phys_addr_t pa = __pgd_pgtable_alloc(pgtable_type); - struct ptdesc *ptdesc = page_ptdesc(phys_to_page(pa)); + BUG_ON(!ptdesc); + pa = page_to_phys(ptdesc_page(ptdesc)); - /* - * Call proper page table ctor in case later we need to - * call core mm functions like apply_to_page_range() on - * this pre-allocated page table. - */ switch (pgtable_type) { case TABLE_PTE: - BUG_ON(!pagetable_pte_ctor(NULL, ptdesc)); + BUG_ON(!pagetable_pte_ctor(mm, ptdesc)); break; case TABLE_PMD: - BUG_ON(!pagetable_pmd_ctor(NULL, ptdesc)); + BUG_ON(!pagetable_pmd_ctor(mm, ptdesc)); break; default: break; @@ -513,6 +504,18 @@ static phys_addr_t pgd_pgtable_alloc(enum pgtable_type pgtable_type) return pa; } +static phys_addr_t __maybe_unused +pgd_pgtable_alloc_init_mm(enum pgtable_type pgtable_type) +{ + return __pgd_pgtable_alloc(&init_mm, pgtable_type); +} + +static phys_addr_t +pgd_pgtable_alloc_special_mm(enum pgtable_type pgtable_type) +{ + return __pgd_pgtable_alloc(NULL, pgtable_type); +} + /* * This function can only be used to modify existing table entries, * without allocating new levels of table. Note that this permits the @@ -542,7 +545,7 @@ void __init create_pgd_mapping(struct mm_struct *mm, phys_addr_t phys, flags = NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS; __create_pgd_mapping(mm->pgd, phys, virt, size, prot, - pgd_pgtable_alloc, flags); + pgd_pgtable_alloc_special_mm, flags); } static void update_mapping_prot(phys_addr_t phys, unsigned long virt, @@ -756,7 +759,7 @@ static int __init map_entry_trampoline(void) memset(tramp_pg_dir, 0, PGD_SIZE); __create_pgd_mapping(tramp_pg_dir, pa_start, TRAMP_VALIAS, entry_tramp_text_size(), prot, - __pgd_pgtable_alloc, NO_BLOCK_MAPPINGS); + pgd_pgtable_alloc_init_mm, NO_BLOCK_MAPPINGS); /* Map both the text and data into the kernel page table */ for (i = 0; i < DIV_ROUND_UP(entry_tramp_text_size(), PAGE_SIZE); i++) @@ -1362,7 +1365,7 @@ int arch_add_memory(int nid, u64 start, u64 size, flags |= NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS; __create_pgd_mapping(swapper_pg_dir, start, __phys_to_virt(start), - size, params->pgprot, __pgd_pgtable_alloc, + size, params->pgprot, pgd_pgtable_alloc_init_mm, flags); memblock_clear_nomap(start, size); From patchwork Tue Apr 8 09:52:20 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Brodsky X-Patchwork-Id: 14042921 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C6A46C36010 for ; Tue, 8 Apr 2025 11:57:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=/xCdomzVQ9UKIUqSV0nOR1Orsi3U0kam6TrHTVmoiR4=; b=X0vneST8xjO2IRzlUqS8dsNF2w xMDIQC35Y02F8jnGHat3RjHEprz/Uqycjke2C51pQWarjp0GCcDNc+dLeAvfXAFjPD1BRT6glWhkv meRyyWhmSlbiir0+VWeWfyO/Cx6nO5KW8Iz4xevoJmD/1TADfjoGipCpX1u5mYkBtAhBv4xnuCxLg FTL/sglsSit33dXnEOybV+NJs3kmzIJrln9Y1LrCnjVogAC1jN+pouu9b3vWo4IKXaweqYD8NEz3w cEUtT050iXsRvnYPPmv4zUzNjEo6RYa+AAv3W8YrMNPmGPr+vMnvQzKX7aq0/kok8M1YIzQB0d/nT bn8I6M1A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u27aN-00000003urJ-1h97; Tue, 08 Apr 2025 11:57:47 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u25eX-00000003WpA-3bGU; Tue, 08 Apr 2025 09:53:59 +0000 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 5D48D16A3; Tue, 8 Apr 2025 02:53:58 -0700 (PDT) Received: from e123572-lin.arm.com (e123572-lin.cambridge.arm.com [10.1.194.54]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 1DCDA3F6A8; Tue, 8 Apr 2025 02:53:52 -0700 (PDT) From: Kevin Brodsky To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Kevin Brodsky , Albert Ou , Andreas Larsson , Andrew Morton , Catalin Marinas , Dave Hansen , "David S. Miller" , Geert Uytterhoeven , Linus Walleij , Madhavan Srinivasan , Mark Rutland , Matthew Wilcox , Michael Ellerman , "Mike Rapoport (IBM)" , Palmer Dabbelt , Paul Walmsley , Peter Zijlstra , Qi Zheng , Ryan Roberts , Will Deacon , Yang Shi , linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-openrisc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, x86@kernel.org Subject: [PATCH v2 10/12] riscv: mm: Clarify ctor mm argument in alloc_{pte,pmd}_late Date: Tue, 8 Apr 2025 10:52:20 +0100 Message-ID: <20250408095222.860601-11-kevin.brodsky@arm.com> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20250408095222.860601-1-kevin.brodsky@arm.com> References: <20250408095222.860601-1-kevin.brodsky@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250408_025357_953760_95240E6B X-CRM114-Status: GOOD ( 15.14 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org pagetable_{pte,pmd}_ctor(mm, ptdesc) skip the ptlock initialisation if mm is &init_mm. To avoid unnecessary overhead, it is therefore preferable to pass the actual mm associated to the PTE/PMD. Unfortunately, this proves challenging for alloc_{pte,pmd}_late() as the associated mm is not available at the point where they are called - in fact not even top-level functions like create_pgd_mapping() are passed the mm. As a result they both call the ctor with NULL as mm; this is safe but potentially wasteful. This is not a new situation, but let's add a couple of comments to clarify it. Signed-off-by: Kevin Brodsky --- arch/riscv/mm/init.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index e5ef693fc778..59a982f88908 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -442,6 +442,11 @@ static phys_addr_t __meminit alloc_pte_late(uintptr_t va) { struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0); + /* + * We do not know which mm the PTE page is associated to at this point. + * Passing NULL to the ctor is the safe option, though it may result + * in unnecessary work (e.g. initialising the ptlock for init_mm). + */ BUG_ON(!ptdesc || !pagetable_pte_ctor(NULL, ptdesc)); return __pa((pte_t *)ptdesc_address(ptdesc)); } @@ -522,6 +527,7 @@ static phys_addr_t __meminit alloc_pmd_late(uintptr_t va) { struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0); + /* See comment in alloc_pte_late() regarding NULL passed the ctor */ BUG_ON(!ptdesc || !pagetable_pmd_ctor(NULL, ptdesc)); return __pa((pmd_t *)ptdesc_address(ptdesc)); } From patchwork Tue Apr 8 09:52:21 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Brodsky X-Patchwork-Id: 14042923 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 36D30C369A6 for ; Tue, 8 Apr 2025 11:57:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=zCqJ5i1RxEJN7X5dUM1nM7yZwBGmu6xdERTmZRAkVic=; b=eKIp+am7+L7NabshGfHFgu2zY2 3zxp8bNx/uDEzdHclAqw3bq76Swhp1S9f/tAOB6bZzH07GwG7ZDTWmNTkho3eKNMzkqOihdcFg/y7 zFMVAU2VxfoOpnurOeYdWhaZeU9L4HpuLxcMzSBR/Ss8CunMN/XlsDBugFepi/jQhRlawrWPO7Mhn sSNehUy3av/MQrtWkoIpBheHLOkrcy0RyDdf1FjbUaA/kG8XN4RRGu0hnJcrr4L7GZzs/Wcgj8Z6s SM5bjZgIvx030Eb/7KaVRX+i/rw5PW7JLm8i3wANn3MzwMs3FjmXdoDZPNuf24Z+arZ9tUGgP0qEo KzeOgecw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u27aO-00000003us5-2WqT; Tue, 08 Apr 2025 11:57:48 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u25ec-00000003WrW-2OZy; Tue, 08 Apr 2025 09:54:07 +0000 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 15DC122FA; Tue, 8 Apr 2025 02:54:03 -0700 (PDT) Received: from e123572-lin.arm.com (e123572-lin.cambridge.arm.com [10.1.194.54]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id CA25B3F6A8; Tue, 8 Apr 2025 02:53:57 -0700 (PDT) From: Kevin Brodsky To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Kevin Brodsky , Albert Ou , Andreas Larsson , Andrew Morton , Catalin Marinas , Dave Hansen , "David S. Miller" , Geert Uytterhoeven , Linus Walleij , Madhavan Srinivasan , Mark Rutland , Matthew Wilcox , Michael Ellerman , "Mike Rapoport (IBM)" , Palmer Dabbelt , Paul Walmsley , Peter Zijlstra , Qi Zheng , Ryan Roberts , Will Deacon , Yang Shi , linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-openrisc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, x86@kernel.org Subject: [PATCH v2 11/12] arm64: mm: Call PUD/P4D ctor in __create_pgd_mapping() Date: Tue, 8 Apr 2025 10:52:21 +0100 Message-ID: <20250408095222.860601-12-kevin.brodsky@arm.com> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20250408095222.860601-1-kevin.brodsky@arm.com> References: <20250408095222.860601-1-kevin.brodsky@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250408_025402_668929_A1998605 X-CRM114-Status: GOOD ( 10.42 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Constructors for PUD/P4D-level pgtables were recently introduced. They should be called for all pgtables; make sure they are called for special kernel mappings created by __create_pgd_mapping() too. Signed-off-by: Kevin Brodsky --- arch/arm64/mm/mmu.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 51cfc891f6a1..8fcf59ba39db 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -497,7 +497,11 @@ static phys_addr_t __pgd_pgtable_alloc(struct mm_struct *mm, case TABLE_PMD: BUG_ON(!pagetable_pmd_ctor(mm, ptdesc)); break; - default: + case TABLE_PUD: + pagetable_pud_ctor(ptdesc); + break; + case TABLE_P4D: + pagetable_p4d_ctor(ptdesc); break; } From patchwork Tue Apr 8 09:52:22 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Brodsky X-Patchwork-Id: 14042779 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id F15F9C3600C for ; Tue, 8 Apr 2025 10:47:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=08E//Tnzm4Otbmgjv5PkMZzFPCICf9ItkLK9Ykz94vQ=; b=s2NZ54WykVDNczLOvw91SJT12e 74N5DEctSBhgw9JM6y613qJm1ahvoR5MLxd2MMpzhVcckt+LGztTIiqAUegnOlX1l8GQuuMR6U//C CQl1V7+QluEM05ks6zntEnzpW95Fyw+/nt9XQVQtdteNzD/RpbFgzqksl1weHyUvbu16gAlnAcQje 1vh/jR22pMgyU96eUxRuewZ7bMT89VwMSJ2Qw0D9JkQSpm5gn+HKeqjams/BD6Px5/IdumWgTy2cN PrVbisUlyPC/9FVR8Eb9jgHhIvUzZU5uoFQtkAIOEvA0QQVU3KQ44P5V3l/TAyPmYloOJsAt7lt06 W7OWnTyQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u26Tx-00000003j9Y-1KAL; Tue, 08 Apr 2025 10:47:05 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.1 #2 (Red Hat Linux)) id 1u25eh-00000003Wty-1Leg; Tue, 08 Apr 2025 09:54:08 +0000 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 C22912308; Tue, 8 Apr 2025 02:54:07 -0700 (PDT) Received: from e123572-lin.arm.com (e123572-lin.cambridge.arm.com [10.1.194.54]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 8289A3F6A8; Tue, 8 Apr 2025 02:54:02 -0700 (PDT) From: Kevin Brodsky To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Kevin Brodsky , Albert Ou , Andreas Larsson , Andrew Morton , Catalin Marinas , Dave Hansen , "David S. Miller" , Geert Uytterhoeven , Linus Walleij , Madhavan Srinivasan , Mark Rutland , Matthew Wilcox , Michael Ellerman , "Mike Rapoport (IBM)" , Palmer Dabbelt , Paul Walmsley , Peter Zijlstra , Qi Zheng , Ryan Roberts , Will Deacon , Yang Shi , linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-openrisc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, x86@kernel.org Subject: [PATCH v2 12/12] riscv: mm: Call PUD/P4D ctor in special kernel pgtable alloc Date: Tue, 8 Apr 2025 10:52:22 +0100 Message-ID: <20250408095222.860601-13-kevin.brodsky@arm.com> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20250408095222.860601-1-kevin.brodsky@arm.com> References: <20250408095222.860601-1-kevin.brodsky@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250408_025407_416396_85117076 X-CRM114-Status: GOOD ( 11.94 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Constructors for PUD/P4D-level pgtables were recently introduced. They should be called for all pgtables; make sure they are called for special kernel mappings created by create_pgd_mapping() too. While at it also switch to using pagetable_alloc() like in alloc_{pte,pmd}_late(). Signed-off-by: Kevin Brodsky --- arch/riscv/mm/init.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index 59a982f88908..8d0374d7ce8e 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -590,11 +590,11 @@ static phys_addr_t __init alloc_pud_fixmap(uintptr_t va) static phys_addr_t __meminit alloc_pud_late(uintptr_t va) { - unsigned long vaddr; + struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL, 0); - vaddr = __get_free_page(GFP_KERNEL); - BUG_ON(!vaddr); - return __pa(vaddr); + BUG_ON(!ptdesc); + pagetable_pud_ctor(ptdesc); + return __pa((pud_t *)ptdesc_address(ptdesc)); } static p4d_t *__init get_p4d_virt_early(phys_addr_t pa) @@ -628,11 +628,11 @@ static phys_addr_t __init alloc_p4d_fixmap(uintptr_t va) static phys_addr_t __meminit alloc_p4d_late(uintptr_t va) { - unsigned long vaddr; + struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL, 0); - vaddr = __get_free_page(GFP_KERNEL); - BUG_ON(!vaddr); - return __pa(vaddr); + BUG_ON(!ptdesc); + pagetable_p4d_ctor(ptdesc); + return __pa((p4d_t *)ptdesc_address(ptdesc)); } static void __meminit create_pud_mapping(pud_t *pudp, uintptr_t va, phys_addr_t pa, phys_addr_t sz,