kernel/arch/m68k/include/asm/sun3_pgalloc.h, branch linux-rolling-stable

mm: pgtable: convert some architectures to use tlb_remove_ptdesc()

2025-04-01T22:17:13Z

Now, the nine architectures of csky, hexagon, loongarch, m68k, mips, nios2, openrisc, sh and um do not select CONFIG_MMU_GATHER_RCU_TABLE_FREE, and just call pagetable_dtor() + tlb_remove_page_ptdesc() (the wrapper of tlb_remove_page()). This is the same as the implementation of tlb_remove_{ptdesc|table}() under !CONFIG_MMU_GATHER_TABLE_FREE, so convert these architectures to use tlb_remove_ptdesc(). The ultimate goal is to make the architecture only use tlb_remove_ptdesc() or tlb_remove_table() for page table pages. [zhengqi.arch@bytedance.com: v2] Link: https://lkml.kernel.org/r/20250303072603.45423-1-zhengqi.arch@bytedance.com [akpm@linux-foundation.org: remove trailing semi in arch/loongarch/include/asm/pgalloc.h] Link: https://lkml.kernel.org/r/19db3e8673b67bad2f1df1ab37f1c89d99eacfea.1740454179.git.zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng Suggested-by: Peter Zijlstra (Intel) Reviewed-by: Kevin Brodsky Acked-by: Geert Uytterhoeven [m68k] Cc: Alexandre Ghiti Cc: "Aneesh Kumar K.V" Cc: Arnd Bergmann Cc: Dave Hansen Cc: David Hildenbrand Cc: Hugh Dickens Cc: Jann Horn Cc: Matthew Wilcow (Oracle) Cc: "Mike Rapoport (IBM)" Cc: Muchun Song Cc: Nicholas Piggin Cc: Rik van Riel Cc: Vishal Moola (Oracle) Cc: Will Deacon Cc: Yu Zhao Signed-off-by: Andrew Morton

m68k: sun3: add check for __pgd_alloc()

2025-03-06T05:36:12Z

Add check for the return value of __pgd_alloc() in pgd_alloc() to prevent null pointer dereference. Link: https://lkml.kernel.org/r/20250217160017.2375536-1-haoxiang_li2024@163.com Fixes: a9b3c355c2e6 ("asm-generic: pgalloc: provide generic __pgd_{alloc,free}") Signed-off-by: Haoxiang Li Reviewed-by: Geert Uytterhoeven Acked-by: Geert Uytterhoeven Cc: Dave Hansen Cc: Kevin Brodsky Cc: Qi Zheng Cc: Sam Creasey Cc: Signed-off-by: Andrew Morton

asm-generic: pgalloc: provide generic __pgd_{alloc,free}

2025-01-26T04:22:24Z

We already have a generic implementation of alloc/free up to P4D level, as well as pgd_free(). Let's finish the work and add a generic PGD-level alloc helper as well. Unlike at lower levels, almost all architectures need some specific magic at PGD level (typically initialising PGD entries), so introducing a generic pgd_alloc() isn't worth it. Instead we introduce two new helpers, __pgd_alloc() and __pgd_free(), and make use of them in the arch-specific pgd_alloc() and pgd_free() wherever possible. To accommodate as many arch as possible, __pgd_alloc() takes a page allocation order. Because pagetable_alloc() allocates zeroed pages, explicit zeroing in pgd_alloc() becomes redundant and we can get rid of it. Some trivial implementations of pgd_free() also become unnecessary once __pgd_alloc() is used; remove them. Another small improvement is consistent accounting of PGD pages by using GFP_PGTABLE_{USER,KERNEL} as appropriate. Not all PGD allocations can be handled by the generic helpers. In particular, multiple architectures allocate PGDs from a kmem_cache, and those PGDs may not be page-sized. Link: https://lkml.kernel.org/r/20250103184415.2744423-6-kevin.brodsky@arm.com Signed-off-by: Kevin Brodsky Acked-by: Dave Hansen Acked-by: Qi Zheng Cc: Andy Lutomirski Cc: Catalin Marinas Cc: Ingo Molnar Cc: Linus Walleij Cc: Matthew Wilcox (Oracle) Cc: Mike Rapoport (Microsoft) Cc: Peter Zijlstra Cc: Ryan Roberts Cc: Thomas Gleixner Cc: Will Deacon Signed-off-by: Andrew Morton

mm: pgtable: introduce pagetable_dtor()

2025-01-26T04:22:22Z

The pagetable_p*_dtor() are exactly the same except for the handling of ptlock. If we make ptlock_free() handle the case where ptdesc->ptl is NULL and remove VM_BUG_ON_PAGE() from pmd_ptlock_free(), we can unify pagetable_p*_dtor() into one function. Let's introduce pagetable_dtor() to do this. Later, pagetable_dtor() will be moved to tlb_remove_ptdesc(), so that ptlock and page table pages can be freed together (regardless of whether RCU is used). This prevents the use-after-free problem where the ptlock is freed immediately but the page table pages is freed later via RCU. Link: https://lkml.kernel.org/r/47f44fff9dc68d9d9e9a0d6c036df275f820598a.1736317725.git.zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng Originally-by: Peter Zijlstra (Intel) Reviewed-by: Kevin Brodsky Acked-by: Alexander Gordeev [s390] Cc: Alexandre Ghiti Cc: Alexandre Ghiti Cc: Andreas Larsson Cc: Aneesh Kumar K.V (Arm) Cc: Arnd Bergmann Cc: Dave Hansen Cc: David Hildenbrand Cc: David Rientjes Cc: Hugh Dickins Cc: Jann Horn Cc: Lorenzo Stoakes Cc: Matthew Wilcox (Oracle) Cc: Mike Rapoport (Microsoft) Cc: Muchun Song Cc: Nicholas Piggin Cc: Palmer Dabbelt Cc: Ryan Roberts Cc: Thomas Gleixner Cc: Vishal Moola (Oracle) Cc: Will Deacon Cc: Yu Zhao Signed-off-by: Andrew Morton

m68k: sun3: Fix indentation by 5 or 7 spaces

2023-10-16T12:30:39Z

Indentation should use TABs, not spaces. Fix whitespace in reindented code while at it. Signed-off-by: Geert Uytterhoeven Link: https://lore.kernel.org/r/167216dfe9795056b7a69415695772887aca6d80.1696602993.git.geert@linux-m68k.org

m68k: convert various functions to use ptdescs

2023-08-21T20:37:56Z

As part of the conversions to replace pgtable constructor/destructors with ptdesc equivalents, convert various page table functions to use ptdescs. Some of the functions use the *get*page*() helper functions. Convert these to use pagetable_alloc() and ptdesc_address() instead to help standardize page tables further. Link: https://lkml.kernel.org/r/20230807230513.102486-23-vishal.moola@gmail.com Signed-off-by: Vishal Moola (Oracle) Acked-by: Mike Rapoport (IBM) Acked-by: Geert Uytterhoeven Cc: Arnd Bergmann Cc: Catalin Marinas Cc: Christophe Leroy Cc: Claudio Imbrenda Cc: Dave Hansen Cc: David Hildenbrand Cc: "David S. Miller" Cc: Dinh Nguyen Cc: Geert Uytterhoeven Cc: Guo Ren Cc: Huacai Chen Cc: Hugh Dickins Cc: John Paul Adrian Glaubitz Cc: Jonas Bonn Cc: Matthew Wilcox Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Richard Weinberger Cc: Thomas Bogendoerfer Cc: Yoshinori Sato Signed-off-by: Andrew Morton

mm/thp: define default pmd_pgtable()

2021-07-01T18:06:03Z

Currently most platforms define pmd_pgtable() as pmd_page() duplicating the same code all over. Instead just define a default value i.e pmd_page() for pmd_pgtable() and let platforms override when required via . All the existing platform that override pmd_pgtable() have been moved into their respective header in order to precede before the new generic definition. This makes it much cleaner with reduced code. Link: https://lkml.kernel.org/r/1623646133-20306-1-git-send-email-anshuman.khandual@arm.com Signed-off-by: Anshuman Khandual Acked-by: Geert Uytterhoeven Acked-by: Mike Rapoport Cc: Nick Hu Cc: Richard Henderson Cc: Vineet Gupta Cc: Catalin Marinas Cc: Will Deacon Cc: Guo Ren Cc: Brian Cain Cc: Geert Uytterhoeven Cc: Michal Simek Cc: Thomas Bogendoerfer Cc: Ley Foon Tan Cc: Jonas Bonn Cc: Stefan Kristiansson Cc: Stafford Horne Cc: "James E.J. Bottomley" Cc: Michael Ellerman Cc: Christophe Leroy Cc: Paul Walmsley Cc: Palmer Dabbelt Cc: Heiko Carstens Cc: Yoshinori Sato Cc: "David S. Miller" Cc: Jeff Dike Cc: Thomas Gleixner Cc: Chris Zankel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

asm-generic: pgalloc: provide generic pgd_free()

2020-08-07T18:33:26Z

Most architectures define pgd_free() as a wrapper for free_page(). Provide a generic version in asm-generic/pgalloc.h and enable its use for most architectures. Signed-off-by: Mike Rapoport Signed-off-by: Andrew Morton Reviewed-by: Pekka Enberg Acked-by: Geert Uytterhoeven [m68k] Cc: Abdul Haleem Cc: Andy Lutomirski Cc: Arnd Bergmann Cc: Christophe Leroy Cc: Joerg Roedel Cc: Joerg Roedel Cc: Max Filippov Cc: Peter Zijlstra (Intel) Cc: Satheesh Rajendran Cc: Stafford Horne Cc: Stephen Rothwell Cc: Steven Rostedt Cc: Matthew Wilcox Link: http://lkml.kernel.org/r/20200627143453.31835-7-rppt@kernel.org Signed-off-by: Linus Torvalds

m68k: mm: use pgtable-nopXd instead of 4level-fixup

2019-12-05T03:44:15Z

m68k has two or three levels of page tables and can use appropriate pgtable-nopXd and folding of the upper layers. Replace usage of include/asm-generic/4level-fixup.h and explicit definitions of __PAGETABLE_PxD_FOLDED in m68k with include/asm-generic/pgtable-nopmd.h for two-level configurations and with include/asm-generic/pgtable-nopud.h for three-lelve configurations and adjust page table manipulation macros and functions accordingly. [akpm@linux-foundation.org: fix merge glitch] [geert@linux-m68k.org: more merge glitch fixes] [akpm@linux-foundation.org: s/bad_pgd/bad_pud/, per Mike] Link: http://lkml.kernel.org/r/1572938135-31886-6-git-send-email-rppt@kernel.org Signed-off-by: Mike Rapoport Acked-by: Greg Ungerer Cc: Anatoly Pugachev Cc: Anton Ivanov Cc: Arnd Bergmann Cc: "David S. Miller" Cc: Geert Uytterhoeven Cc: Greentime Hu Cc: Helge Deller Cc: "James E.J. Bottomley" Cc: Jeff Dike Cc: "Kirill A. Shutemov" Cc: Mark Salter Cc: Matt Turner Cc: Michal Simek Cc: Peter Rosin Cc: Richard Weinberger Cc: Rolf Eike Beer Cc: Russell King Cc: Russell King Cc: Sam Creasey Cc: Vincent Chen Cc: Vineet Gupta Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: treewide: clarify pgtable_page_{ctor,dtor}() naming

2019-09-26T17:10:44Z

The naming of pgtable_page_{ctor,dtor}() seems to have confused a few people, and until recently arm64 used these erroneously/pointlessly for other levels of page table. To make it incredibly clear that these only apply to the PTE level, and to align with the naming of pgtable_pmd_page_{ctor,dtor}(), let's rename them to pgtable_pte_page_{ctor,dtor}(). These changes were generated with the following shell script: ---- git grep -lw 'pgtable_page_.tor' | while read FILE; do sed -i '{s/pgtable_page_ctor/pgtable_pte_page_ctor/}' $FILE; sed -i '{s/pgtable_page_dtor/pgtable_pte_page_dtor/}' $FILE; done ---- ... with the documentation re-flowed to remain under 80 columns, and whitespace fixed up in macros to keep backslashes aligned. There should be no functional change as a result of this patch. Link: http://lkml.kernel.org/r/20190722141133.3116-1-mark.rutland@arm.com Signed-off-by: Mark Rutland Reviewed-by: Mike Rapoport Acked-by: Geert Uytterhoeven [m68k] Cc: Anshuman Khandual Cc: Matthew Wilcox Cc: Michal Hocko Cc: Yu Zhao Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds