kernel/linux.git/arch/arm/include/asm/pgtable.h, branch v6.12.80

arm/pgtable: define PFN_PTE_SHIFT

2024-02-22T18:24:50+00:00

We want to make use of pte_next_pfn() outside of set_ptes(). Let's simply define PFN_PTE_SHIFT, required by pte_next_pfn(). Link: https://lkml.kernel.org/r/20240129124649.189745-3-david@redhat.com Signed-off-by: David Hildenbrand Tested-by: Ryan Roberts Reviewed-by: Mike Rapoport (IBM) Cc: Albert Ou Cc: Alexander Gordeev Cc: Alexandre Ghiti Cc: Aneesh Kumar K.V Cc: Catalin Marinas Cc: Christian Borntraeger Cc: Christophe Leroy Cc: David S. Miller Cc: Dinh Nguyen Cc: Gerald Schaefer Cc: Heiko Carstens Cc: Matthew Wilcox Cc: Michael Ellerman Cc: Naveen N. Rao Cc: Nicholas Piggin Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Russell King (Oracle) Cc: Sven Schnelle Cc: Vasily Gorbik Cc: Will Deacon Signed-off-by: Andrew Morton

mm: Introduce pudp/p4dp/pgdp_get() functions

2023-12-20T18:48:13+00:00

Instead of directly dereferencing page tables entries, which can cause issues (see commit 20a004e7b017 ("arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables"), let's introduce new functions to get the pud/p4d/pgd entries (the pte and pmd versions already exist). Note that arm pgd_t is actually an array so pgdp_get() is defined as a macro to avoid a build error. Those new functions will be used in subsequent commits by the riscv architecture. Signed-off-by: Alexandre Ghiti Link: https://lore.kernel.org/r/20231213203001.179237-3-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt

Merge tag 'x86_shstk_for_6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2023-08-31T19:20:12+00:00

Pull x86 shadow stack support from Dave Hansen: "This is the long awaited x86 shadow stack support, part of Intel's Control-flow Enforcement Technology (CET). CET consists of two related security features: shadow stacks and indirect branch tracking. This series implements just the shadow stack part of this feature, and just for userspace. The main use case for shadow stack is providing protection against return oriented programming attacks. It works by maintaining a secondary (shadow) stack using a special memory type that has protections against modification. When executing a CALL instruction, the processor pushes the return address to both the normal stack and to the special permission shadow stack. Upon RET, the processor pops the shadow stack copy and compares it to the normal stack copy. For more information, refer to the links below for the earlier versions of this patch set" Link: https://lore.kernel.org/lkml/20220130211838.8382-1-rick.p.edgecombe@intel.com/ Link: https://lore.kernel.org/lkml/20230613001108.3040476-1-rick.p.edgecombe@intel.com/ * tag 'x86_shstk_for_6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (47 commits) x86/shstk: Change order of __user in type x86/ibt: Convert IBT selftest to asm x86/shstk: Don't retry vm_munmap() on -EINTR x86/kbuild: Fix Documentation/ reference x86/shstk: Move arch detail comment out of core mm x86/shstk: Add ARCH_SHSTK_STATUS x86/shstk: Add ARCH_SHSTK_UNLOCK x86: Add PTRACE interface for shadow stack selftests/x86: Add shadow stack test x86/cpufeatures: Enable CET CR4 bit for shadow stack x86/shstk: Wire in shadow stack interface x86: Expose thread features in /proc/$PID/status x86/shstk: Support WRSS for userspace x86/shstk: Introduce map_shadow_stack syscall x86/shstk: Check that signal frame is shadow stack mem x86/shstk: Check that SSP is aligned on sigreturn x86/shstk: Handle signals for shadow stack x86/shstk: Introduce routines modifying shstk x86/shstk: Handle thread shadow stack x86/shstk: Add user-mode shadow stack support ...

arm: implement the new page table range API

2023-08-24T23:20:20+00:00

Add set_ptes(), update_mmu_cache_range(), flush_dcache_folio() and flush_icache_pages(). Change the PG_dcache_clear flag from being per-page to per-folio which makes __dma_page_dev_to_cpu() a bit more exciting. Also add flush_cache_pages(), even though this isn't used by generic code (yet?) [m.szyprowski@samsung.com: fix potential endless loop in __dma_page_dev_to_cpu()] Link: https://lkml.kernel.org/r/20230809172737.3574190-1-m.szyprowski@samsung.com [willy@infradead.org: fix folio conversion in __dma_page_dev_to_cpu()] Link: https://lkml.kernel.org/r/20230823191852.1556561-1-willy@infradead.org Link: https://lkml.kernel.org/r/20230802151406.3735276-10-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Marek Szyprowski Acked-by: Mike Rapoport (IBM) Reviewed-by: Russell King (Oracle) Signed-off-by: Andrew Morton

mm: Rename arch pte_mkwrite()'s to pte_mkwrite_novma()

2023-07-11T21:10:56+00:00

The x86 Shadow stack feature includes a new type of memory called shadow stack. This shadow stack memory has some unusual properties, which requires some core mm changes to function properly. One of these unusual properties is that shadow stack memory is writable, but only in limited ways. These limits are applied via a specific PTE bit combination. Nevertheless, the memory is writable, and core mm code will need to apply the writable permissions in the typical paths that call pte_mkwrite(). The goal is to make pte_mkwrite() take a VMA, so that the x86 implementation of it can know whether to create regular writable or shadow stack mappings. But there are a couple of challenges to this. Modifying the signatures of each arch pte_mkwrite() implementation would be error prone because some are generated with macros and would need to be re-implemented. Also, some pte_mkwrite() callers operate on kernel memory without a VMA. So this can be done in a three step process. First pte_mkwrite() can be renamed to pte_mkwrite_novma() in each arch, with a generic pte_mkwrite() added that just calls pte_mkwrite_novma(). Next callers without a VMA can be moved to pte_mkwrite_novma(). And lastly, pte_mkwrite() and all callers can be changed to take/pass a VMA. Start the process by renaming pte_mkwrite() to pte_mkwrite_novma() and adding the pte_mkwrite() wrapper in linux/pgtable.h. Apply the same pattern for pmd_mkwrite(). Since not all archs have a pmd_mkwrite_novma(), create a new arch config HAS_HUGE_PAGE that can be used to tell if pmd_mkwrite() should be defined. Otherwise in the !HAS_HUGE_PAGE cases the compiler would not be able to find pmd_mkwrite_novma(). No functional change. Suggested-by: Linus Torvalds Signed-off-by: Rick Edgecombe Signed-off-by: Dave Hansen Reviewed-by: Mike Rapoport (IBM) Acked-by: Geert Uytterhoeven Acked-by: David Hildenbrand Link: https://lore.kernel.org/lkml/CAHk-=wiZjSu7c9sFYZb3q04108stgHff2wfbokGCCgW7riz+8Q@mail.gmail.com/ Link: https://lore.kernel.org/all/20230613001108.3040476-2-rick.p.edgecombe%40intel.com

ARM: mm: Make virt_to_pfn() a static inline

2023-05-29T09:27:08+00:00

Making virt_to_pfn() a static inline taking a strongly typed (const void *) makes the contract of a passing a pointer of that type to the function explicit and exposes any misuse of the macro virt_to_pfn() acting polymorphic and accepting many types such as (void *), (unitptr_t) or (unsigned long) as arguments without warnings. Doing this is a bit intrusive: virt_to_pfn() requires PHYS_PFN_OFFSET and PAGE_SHIFT to be defined, and this is defined in , so this must be included *before* . The use of macros were obscuring the unclear inclusion order here, as the macros would eventually be resolved, but a static inline like this cannot be compiled with unresolved macros. The naive solution to include at the top of does not work, because sometimes includes at the end of itself, which would create a confusing inclusion loop. So instead, take the approach to always unconditionally include at the end of arch/arm uses explicitly in a lot of places, however it turns out that if we just unconditionally include into and switch all inclusions of to instead, we enforce the right order and will always have access to the definitions. Put an inclusion guard in place making it impossible to include explicitly. Link: https://lore.kernel.org/linux-mm/20220701160004.2ffff4e5ab59a55499f4c736@linux-foundation.org/ Signed-off-by: Linus Walleij

arm/mm: fix swp type masking in __swp_entry()

2023-02-10T00:51:30+00:00

We're masking with the number of type bits instead of the type mask, which is obviously wrong. Link: https://lkml.kernel.org/r/39fd91e3-c93b-23c6-afc6-cbe473bb0ca9@redhat.com Fixes: 20aae9eff5ac ("arm/mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE") Signed-off-by: David Hildenbrand Reported-by: Mark Brown Tested-by: Mark Brown Cc: Russell King (Oracle) Signed-off-by: Andrew Morton

mm: remove __HAVE_ARCH_PTE_SWP_EXCLUSIVE

2023-02-03T06:33:11+00:00

__HAVE_ARCH_PTE_SWP_EXCLUSIVE is now supported by all architectures that support swp PTEs, so let's drop it. Link: https://lkml.kernel.org/r/20230113171026.582290-27-david@redhat.com Signed-off-by: David Hildenbrand Signed-off-by: Andrew Morton

arm/mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE

2023-02-03T06:33:06+00:00

Let's support __HAVE_ARCH_PTE_SWP_EXCLUSIVE by stealing one bit from the offset. This reduces the maximum swap space per file to 64 GiB (was 128 GiB). While at it drop the PTE_TYPE_FAULT from __swp_entry_to_pte() which is defined to be 0 and is rather confusing because we should be dealing with "Linux PTEs" not "hardware PTEs". Also, properly mask the type in __swp_entry(). Link: https://lkml.kernel.org/r/20230113171026.582290-5-david@redhat.com Signed-off-by: David Hildenbrand Reviewed-by: Russell King (Oracle) Signed-off-by: Andrew Morton

Merge tag 'mm-stable-2022-12-13' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2022-12-14T03:29:45+00:00

Pull MM updates from Andrew Morton: - More userfaultfs work from Peter Xu - Several convert-to-folios series from Sidhartha Kumar and Huang Ying - Some filemap cleanups from Vishal Moola - David Hildenbrand added the ability to selftest anon memory COW handling - Some cpuset simplifications from Liu Shixin - Addition of vmalloc tracing support by Uladzislau Rezki - Some pagecache folioifications and simplifications from Matthew Wilcox - A pagemap cleanup from Kefeng Wang: we have VM_ACCESS_FLAGS, so use it - Miguel Ojeda contributed some cleanups for our use of the __no_sanitize_thread__ gcc keyword. This series should have been in the non-MM tree, my bad - Naoya Horiguchi improved the interaction between memory poisoning and memory section removal for huge pages - DAMON cleanups and tuneups from SeongJae Park - Tony Luck fixed the handling of COW faults against poisoned pages - Peter Xu utilized the PTE marker code for handling swapin errors - Hugh Dickins reworked compound page mapcount handling, simplifying it and making it more efficient - Removal of the autonuma savedwrite infrastructure from Nadav Amit and David Hildenbrand - zram support for multiple compression streams from Sergey Senozhatsky - David Hildenbrand reworked the GUP code's R/O long-term pinning so that drivers no longer need to use the FOLL_FORCE workaround which didn't work very well anyway - Mel Gorman altered the page allocator so that local IRQs can remnain enabled during per-cpu page allocations - Vishal Moola removed the try_to_release_page() wrapper - Stefan Roesch added some per-BDI sysfs tunables which are used to prevent network block devices from dirtying excessive amounts of pagecache - David Hildenbrand did some cleanup and repair work on KSM COW breaking - Nhat Pham and Johannes Weiner have implemented writeback in zswap's zsmalloc backend - Brian Foster has fixed a longstanding corner-case oddity in file[map]_write_and_wait_range() - sparse-vmemmap changes for MIPS, LoongArch and NIOS2 from Feiyang Chen - Shiyang Ruan has done some work on fsdax, to make its reflink mode work better under xfstests. Better, but still not perfect - Christoph Hellwig has removed the .writepage() method from several filesystems. They only need .writepages() - Yosry Ahmed wrote a series which fixes the memcg reclaim target beancounting - David Hildenbrand has fixed some of our MM selftests for 32-bit machines - Many singleton patches, as usual * tag 'mm-stable-2022-12-13' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (313 commits) mm/hugetlb: set head flag before setting compound_order in __prep_compound_gigantic_folio mm: mmu_gather: allow more than one batch of delayed rmaps mm: fix typo in struct pglist_data code comment kmsan: fix memcpy tests mm: add cond_resched() in swapin_walk_pmd_entry() mm: do not show fs mm pc for VM_LOCKONFAULT pages selftests/vm: ksm_functional_tests: fixes for 32bit selftests/vm: cow: fix compile warning on 32bit selftests/vm: madv_populate: fix missing MADV_POPULATE_(READ|WRITE) definitions mm/gup_test: fix PIN_LONGTERM_TEST_READ with highmem mm,thp,rmap: fix races between updates of subpages_mapcount mm: memcg: fix swapcached stat accounting mm: add nodes= arg to memory.reclaim mm: disable top-tier fallback to reclaim on proactive reclaim selftests: cgroup: make sure reclaim target memcg is unprotected selftests: cgroup: refactor proactive reclaim code to reclaim_until() mm: memcg: fix stale protection of reclaim target memcg mm/mmap: properly unaccount memory on mas_preallocate() failure omfs: remove ->writepage jfs: remove ->writepage ...