kernel/linux.git/arch/microblaze/mm, branch v6.18.22

mm: call ctor/dtor for kernel PTEs

2025-05-12T00:48:21+00:00

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/ Link: https://lkml.kernel.org/r/20250408095222.860601-4-kevin.brodsky@arm.com Signed-off-by: Kevin Brodsky Reviewed-by: Alexander Gordeev # s390 Cc: Albert Ou Cc: Andreas Larsson Cc: Catalin Marinas Cc: David S. Miller Cc: Geert Uytterhoeven Cc: Linus Waleij Cc: Madhavan Srinivasan Cc: Mark Rutland Cc: Matthew Wilcox (Oracle) Cc: Michael Ellerman Cc: Mike Rapoport Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Qi Zheng Cc: Ryan Roberts Cc: Will Deacon Cc: Cc: Yang Shi Cc: Dave Hansen Signed-off-by: Andrew Morton

microblaze/mm: put mm_cmdline_setup() in .init.text section

2025-04-01T22:17:13+00:00

As reported by lkp, there is a section mismatch of mm_cmdline_setup() and memblock. The reason is we don't specify the section of mm_cmdline_setup() and gcc put it into .text.unlikely. As mm_cmdline_setup() is only used in mmu_init(), which is in .init.text section, put mm_cmdline_setup() into it too. Link: https://lkml.kernel.org/r/20250328010136.13139-1-richard.weiyang@gmail.com Signed-off-by: Wei Yang Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202503241259.kJV3U7Xj-lkp@intel.com/ Reviewed-by: Oscar Salvador Cc: Masahiro Yamada Cc: Michal Simek Cc: Wei Yang Signed-off-by: Andrew Morton

arch, mm: make releasing of memory to page allocator more explicit

2025-03-18T05:06:53+00:00

The point where the memory is released from memblock to the buddy allocator is hidden inside arch-specific mem_init()s and the call to memblock_free_all() is needlessly duplicated in every artiste cure and after introduction of arch_mm_preinit() hook, mem_init() implementation on many architecture only contains the call to memblock_free_all(). Pull memblock_free_all() call into mm_core_init() and drop mem_init() on relevant architectures to make it more explicit where the free memory is released from memblock to the buddy allocator and to reduce code duplication in architecture specific code. Link: https://lkml.kernel.org/r/20250313135003.836600-14-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) Acked-by: Dave Hansen [x86] Acked-by: Geert Uytterhoeven [m68k] Tested-by: Mark Brown Cc: Alexander Gordeev Cc: Andreas Larsson Cc: Andy Lutomirski Cc: Ard Biesheuvel Cc: Arnd Bergmann Cc: Borislav Betkov Cc: Catalin Marinas Cc: David S. Miller Cc: Dinh Nguyen Cc: Gerald Schaefer Cc: Guo Ren (csky) Cc: Heiko Carstens Cc: Helge Deller Cc: Huacai Chen Cc: Ingo Molnar Cc: Jiaxun Yang Cc: Johannes Berg Cc: John Paul Adrian Glaubitz Cc: Madhavan Srinivasan Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Michal Simek Cc: Palmer Dabbelt Cc: Richard Weinberger Cc: Russel King Cc: Stafford Horne Cc: Thomas Bogendoerfer Cc: Thomas Gleinxer Cc: Vasily Gorbik Cc: Vineet Gupta Cc: Will Deacon Signed-off-by: Andrew Morton

arch, mm: streamline HIGHMEM freeing

2025-03-18T05:06:53+00:00

All architectures that support HIGHMEM have their code that frees high memory pages to the buddy allocator while __free_memory_core() is limited to freeing only low memory. There is no actual reason for that. The memory map is completely ready by the time memblock_free_all() is called and high pages can be released to the buddy allocator along with low memory. Remove low memory limit from __free_memory_core() and drop per-architecture code that frees high memory pages. Link: https://lkml.kernel.org/r/20250313135003.836600-12-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) Acked-by: Dave Hansen [x86] Tested-by: Mark Brown Cc: Alexander Gordeev Cc: Andreas Larsson Cc: Andy Lutomirski Cc: Ard Biesheuvel Cc: Arnd Bergmann Cc: Borislav Betkov Cc: Catalin Marinas Cc: David S. Miller Cc: Dinh Nguyen Cc: Geert Uytterhoeven Cc: Gerald Schaefer Cc: Guo Ren (csky) Cc: Heiko Carstens Cc: Helge Deller Cc: Huacai Chen Cc: Ingo Molnar Cc: Jiaxun Yang Cc: Johannes Berg Cc: John Paul Adrian Glaubitz Cc: Madhavan Srinivasan Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Michal Simek Cc: Palmer Dabbelt Cc: Richard Weinberger Cc: Russel King Cc: Stafford Horne Cc: Thomas Bogendoerfer Cc: Thomas Gleinxer Cc: Vasily Gorbik Cc: Vineet Gupta Cc: Will Deacon Signed-off-by: Andrew Morton

arch, mm: set high_memory in free_area_init()

2025-03-18T05:06:52+00:00

high_memory defines upper bound on the directly mapped memory. This bound is defined by the beginning of ZONE_HIGHMEM when a system has high memory and by the end of memory otherwise. All this is known to generic memory management initialization code that can set high_memory while initializing core mm structures. Add a generic calculation of high_memory to free_area_init() and remove per-architecture calculation except for the architectures that set and use high_memory earlier than that. Link: https://lkml.kernel.org/r/20250313135003.836600-11-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) Acked-by: Dave Hansen [x86] Tested-by: Mark Brown Cc: Alexander Gordeev Cc: Andreas Larsson Cc: Andy Lutomirski Cc: Ard Biesheuvel Cc: Arnd Bergmann Cc: Borislav Betkov Cc: Catalin Marinas Cc: David S. Miller Cc: Dinh Nguyen Cc: Geert Uytterhoeven Cc: Gerald Schaefer Cc: Guo Ren (csky) Cc: Heiko Carstens Cc: Helge Deller Cc: Huacai Chen Cc: Ingo Molnar Cc: Jiaxun Yang Cc: Johannes Berg Cc: John Paul Adrian Glaubitz Cc: Madhavan Srinivasan Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Michal Simek Cc: Palmer Dabbelt Cc: Richard Weinberger Cc: Russel King Cc: Stafford Horne Cc: Thomas Bogendoerfer Cc: Thomas Gleinxer Cc: Vasily Gorbik Cc: Vineet Gupta Cc: Will Deacon Signed-off-by: Andrew Morton

arch, mm: set max_mapnr when allocating memory map for FLATMEM

2025-03-18T05:06:52+00:00

max_mapnr is essentially the size of the memory map for systems that use FLATMEM. There is no reason to calculate it in each and every architecture when it's anyway calculated in alloc_node_mem_map(). Drop setting of max_mapnr from architecture code and set it once in alloc_node_mem_map(). While on it, move definition of mem_map and max_mapnr to mm/mm_init.c so there won't be two copies for MMU and !MMU variants. Link: https://lkml.kernel.org/r/20250313135003.836600-10-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) Acked-by: Dave Hansen [x86] Tested-by: Mark Brown Cc: Alexander Gordeev Cc: Andreas Larsson Cc: Andy Lutomirski Cc: Ard Biesheuvel Cc: Arnd Bergmann Cc: Borislav Betkov Cc: Catalin Marinas Cc: David S. Miller Cc: Dinh Nguyen Cc: Geert Uytterhoeven Cc: Gerald Schaefer Cc: Guo Ren (csky) Cc: Heiko Carstens Cc: Helge Deller Cc: Huacai Chen Cc: Ingo Molnar Cc: Jiaxun Yang Cc: Johannes Berg Cc: John Paul Adrian Glaubitz Cc: Madhavan Srinivasan Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Michal Simek Cc: Palmer Dabbelt Cc: Richard Weinberger Cc: Russel King Cc: Stafford Horne Cc: Thomas Bogendoerfer Cc: Thomas Gleinxer Cc: Vasily Gorbik Cc: Vineet Gupta Cc: Will Deacon Signed-off-by: Andrew Morton

microblaze: don't treat zero reserved memory regions as error

2024-08-25T22:26:30+00:00

Before commit 721f4a6526da ("mm/memblock: remove empty dummy entry") the check for non-zero of memblock.reserved.cnt in mmu_init() would always be true either because memblock.reserved.cnt is initialized to 1 or because there were memory reservations earlier. The removal of dummy empty entry in memblock caused this check to fail because now memblock.reserved.cnt is initialized to 0. Remove the check for non-zero of memblock.reserved.cnt because it's perfectly fine to have an empty memblock.reserved array that early in boot. Reported-by: Guenter Roeck Signed-off-by: Mike Rapoport Reviewed-by: Wei Yang Tested-by: Guenter Roeck Link: https://lore.kernel.org/r/20240729053327.4091459-1-rppt@kernel.org Signed-off-by: Guenter Roeck

microblaze: Remove zalloc_maybe_bootmem()

2023-08-23T07:35:22+00:00

Last user of zalloc_maybe_bootmem() was removed by commit 4308e3c9e1ea ("microblaze/PCI: Remove unused allocation & free of PCI host bridge structure") Remove it. Signed-off-by: Christophe Leroy Link: https://lore.kernel.org/r/bfb1601cac24d7ef8e741c83f9301e4a5a87a0b5.1692124505.git.christophe.leroy@csgroup.eu Signed-off-by: Michal Simek

mm: always expand the stack with the mmap write lock held

2023-06-27T16:41:30+00:00

This finishes the job of always holding the mmap write lock when extending the user stack vma, and removes the 'write_locked' argument from the vm helper functions again. For some cases, we just avoid expanding the stack at all: drivers and page pinning really shouldn't be extending any stacks. Let's see if any strange users really wanted that. It's worth noting that architectures that weren't converted to the new lock_mm_and_find_vma() helper function are left using the legacy "expand_stack()" function, but it has been changed to drop the mmap_lock and take it for writing while expanding the vma. This makes it fairly straightforward to convert the remaining architectures. As a result of dropping and re-taking the lock, the calling conventions for this function have also changed, since the old vma may no longer be valid. So it will now return the new vma if successful, and NULL - and the lock dropped - if the area could not be extended. Tested-by: Vegard Nossum Tested-by: John Paul Adrian Glaubitz # ia64 Tested-by: Frank Scheiner # ia64 Signed-off-by: Linus Torvalds

microblaze: fix livelock in uaccess

2023-03-02T17:32:31+00:00

microblaze equivalent of 26178ec11ef3 "x86: mm: consolidate VM_FAULT_RETRY handling" If e.g. get_user() triggers a page fault and a fatal signal is caught, we might end up with handle_mm_fault() returning VM_FAULT_RETRY and not doing anything to page tables. In such case we must *not* return to the faulting insn - that would repeat the entire thing without making any progress; what we need instead is to treat that as failed (user) memory access. Signed-off-by: Al Viro