Changes in vdso.c

0061b6e1 - mseal sysmap: enable arm64

Wed, 05 Mar 2025 02:17:08 +0000

mseal sysmap: enable arm64Provide support for CONFIG_MSEAL_SYSTEM_MAPPINGS on arm64, covering thevdso, vvar, and compat-mode vectors and sigpage mappings.Production release testing passes on Android and Chrome OS.Link: https://lkml.kernel.org/r/20250305021711.3867874-5-jeffxu@google.comSigned-off-by: Jeff Xu Reviewed-by: Lorenzo Stoakes Reviewed-by: Liam R. Howlett Reviewed-by: Kees Cook Cc: Adhemerval Zanella Cc: Alexander Mikhalitsyn Cc: Alexey Dobriyan Cc: Andrei Vagin Cc: Anna-Maria Behnsen Cc: Ard Biesheuvel Cc: Benjamin Berg Cc: Christoph Hellwig Cc: Dave Hansen Cc: David Rientjes Cc: David S. Miller Cc: Elliot Hughes Cc: Florian Faineli Cc: Greg Ungerer Cc: Guenter Roeck Cc: Heiko Carstens Cc: Helge Deller Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>Cc: Ingo Molnar Cc: Jann Horn Cc: Jason A. Donenfeld Cc: Johannes Berg Cc: Jorge Lucangeli Obes Cc: Linus Waleij Cc: Mark Rutland Cc: Matthew Wilcow (Oracle) Cc: Michael Ellerman Cc: Michal Hocko Cc: Miguel Ojeda Cc: Mike Rapoport Cc: Oleg Nesterov Cc: Pedro Falcato Cc: Peter Xu Cc: Randy Dunlap Cc: Stephen Röttger Cc: Thomas Weißschuh Cc: Vlastimil Babka Signed-off-by: Andrew Morton List of files: /linux-6.15/arch/arm64/kernel/vdso.c

0b3bc335 - arm64: vdso: Switch to generic storage implementation

Tue, 04 Feb 2025 12:05:40 +0000

arm64: vdso: Switch to generic storage implementationThe generic storage implementation provides the same features as thecustom one. However it can be shared between architectures, makingmaintenance easier.This switch also moves the random state data out of the time data page.The currently used hardcoded __VDSO_RND_DATA_OFFSET does not take intoaccount changes to the time data page layout.Co-developed-by: Nam Cao Signed-off-by: Nam Cao Signed-off-by: Thomas Weißschuh Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/20250204-vdso-store-rng-v3-8-13a4669dfc8c@linutronix.de List of files: /linux-6.15/arch/arm64/kernel/vdso.c

461c9668 - arm64: vdso: Use only one single vvar mapping

Thu, 10 Oct 2024 07:01:07 +0000

arm64: vdso: Use only one single vvar mappingThe vvar mapping is the same for all processes. Use a single mapping tosimplify the logic and align it with the other architectures.In addition this will enable the move of the vvar handling into generic code.Signed-off-by: Thomas Weißschuh Signed-off-by: Thomas Gleixner Tested-by: Will Deacon Acked-by: Will Deacon Link: https://lore.kernel.org/all/20241010-vdso-generic-base-v1-5-b64f0842d512@linutronix.de List of files: /linux-6.15/arch/arm64/kernel/vdso.c

86036525 - arm64: vdso: Remove timekeeper include

Thu, 10 Oct 2024 15:44:46 +0000

arm64: vdso: Remove timekeeper includeSince the generic VDSO clock mode storage is used, this header file isunused and can be removed.Signed-off-by: Thomas Weißschuh Signed-off-by: Thomas Gleixner Acked-by: Will Deacon Link: https://lore.kernel.org/all/20241010-vdso-generic-arch_update_vsyscall-v1-3-7fe5a3ea4382@linutronix.de List of files: /linux-6.15/arch/arm64/kernel/vdso.c

712676ea - arm64: vDSO: Wire up getrandom() vDSO implementation

Tue, 03 Sep 2024 12:09:17 +0000

arm64: vDSO: Wire up getrandom() vDSO implementationHook up the generic vDSO implementation to the aarch64 vDSO data page.The _vdso_rng_data required data is placed within the _vdso_data vvarpage, by using a offset larger than the vdso_data.The vDSO function requires a ChaCha20 implementation that does not writeto the stack, and that can do an entire ChaCha20 permutation. The oneprovided uses NEON on the permute operation, with a fallback to thesyscall for chips that do not support AdvSIMD.This also passes the vdso_test_chacha test along withvdso_test_getrandom. The vdso_test_getrandom bench-single result onNeoverse-N1 shows: vdso: 25000000 times in 0.783884250 seconds libc: 25000000 times in 8.780275399 secondssyscall: 25000000 times in 8.786581518 secondsA small fixup to arch/arm64/include/asm/mman.h was required to avoidpulling kernel code into the vDSO, similar to what's already done inarch/arm64/include/asm/rwonce.h.Signed-off-by: Adhemerval Zanella Reviewed-by: Ard Biesheuvel Acked-by: Will Deacon Signed-off-by: Jason A. Donenfeld List of files: /linux-6.15/arch/arm64/kernel/vdso.c

d0fba048 - arm64: vdso: Use generic union vdso_data_store

Mon, 19 Feb 2024 15:39:34 +0000

arm64: vdso: Use generic union vdso_data_storeThere is already a generic union definition for vdso_data_store in vdsodatapage header.Use this definition to prevent code duplication.Signed-off-by: Anna-Maria Behnsen Signed-off-by: Thomas Gleixner Reviewed-by: Vincenzo Frascino Reviewed-by: Kees Cook Link: https://lore.kernel.org/r/20240219153939.75719-6-anna-maria@linutronix.de List of files: /linux-6.15/arch/arm64/kernel/vdso.c

bbbb6577 - arm64: Avoid cpus_have_const_cap() for ARM64_HAS_BTI

Mon, 16 Oct 2023 10:24:39 +0000

arm64: Avoid cpus_have_const_cap() for ARM64_HAS_BTIIn system_supports_bti() we use cpus_have_const_cap() to check forARM64_HAS_BTI, but this is not necessary and alternative_has_cap_*() orcpus_have_final_*cap() would be preferable.For historical reasons, cpus_have_const_cap() is more complicated thanit needs to be. Before cpucaps are finalized, it will perform a bitmaptest of the system_cpucaps bitmap, and once cpucaps are finalized itwill use an alternative branch. This used to be necessary to handle somerace conditions in the window between cpucap detection and thesubsequent patching of alternatives and static branches, where differentbranches could be out-of-sync with one another (or w.r.t. alternativesequences). Now that we use alternative branches instead of staticbranches, these are all patched atomically w.r.t. one another, and thereare only a handful of cases that need special care in the window betweencpucap detection and alternative patching.Due to the above, it would be nice to remove cpus_have_const_cap(), andmigrate callers over to alternative_has_cap_*(), cpus_have_final_cap(),or cpus_have_cap() depending on when their requirements. This willremove redundant instructions and improve code generation, and will makeit easier to determine how each callsite will behave before, during, andafter alternative patching.When CONFIG_ARM64_BTI_KERNEL=y, the ARM64_HAS_BTI cpucap is a strictboot cpu feature which is detected and patched early on the boot cpu.All uses guarded by CONFIG_ARM64_BTI_KERNEL happen after the boot CPUhas detected ARM64_HAS_BTI and patched boot alternatives, and hence cansafely use alternative_has_cap_*() or cpus_have_final_boot_cap().Regardless of CONFIG_ARM64_BTI_KERNEL, all other uses of ARM64_HAS_BTIhappen after system capabilities have been finalized and alternativeshave been patched. Hence these can safely use alternative_has_cap_*) orcpus_have_final_cap().This patch splits system_supports_bti() into system_supports_bti() andsystem_supports_bti_kernel(), with the former handling where the cpucapaffects userspace functionality, and ther latter handling where thecpucap affects kernel functionality. The use of cpus_have_const_cap() isreplaced by cpus_have_final_cap() in cpus_have_const_cap, andcpus_have_final_boot_cap() in system_supports_bti_kernel(). This willavoid generating code to test the system_cpucaps bitmap and should bebetter for all subsequent calls at runtime. The use ofcpus_have_final_cap() and cpus_have_final_boot_cap() will make it easierto spot if code is chaanged such that these run before the ARM64_HAS_BTIcpucap is guaranteed to have been finalized.Signed-off-by: Mark Rutland Reviewed-by: Mark Brown Cc: Ard Biesheuvel Cc: Suzuki K Poulose Cc: Will Deacon Signed-off-by: Catalin Marinas List of files: /linux-6.15/arch/arm64/kernel/vdso.c

b0abde80 - arm64: vdso: Pass (void *) to virt_to_page()

Wed, 10 May 2023 06:48:11 +0000

arm64: vdso: Pass (void *) to virt_to_page()Like the other calls in this function virt_to_page() expectsa pointer, not an integer.However since many architectures implement virt_to_pfn() asa macro, this function becomes polymorphic and accepts both a(unsigned long) and a (void *).Fix this up with an explicit cast.Signed-off-by: Linus Walleij Link: http://lists.infradead.org/pipermail/linux-arm-kernel/2023-May/832583.htmlSigned-off-by: Will Deacon List of files: /linux-6.15/arch/arm64/kernel/vdso.c

e9adcfec - mm: remove zap_page_range and create zap_vma_pages

Wed, 04 Jan 2023 00:27:32 +0000

mm: remove zap_page_range and create zap_vma_pageszap_page_range was originally designed to unmap pages within an addressrange that could span multiple vmas. While working on [1], it wasdiscovered that all callers of zap_page_range pass a range entirely withina single vma. In addition, the mmu notification call within zap_pagerange does not correctly handle ranges that span multiple vmas. Whencrossing a vma boundary, a new mmu_notifier_range_init/end call pair withthe new vma should be made.Instead of fixing zap_page_range, do the following:- Create a new routine zap_vma_pages() that will remove all pages within the passed vma. Most users of zap_page_range pass the entire vma and can use this new routine.- For callers of zap_page_range not passing the entire vma, instead call zap_page_range_single().- Remove zap_page_range.[1] https://lore.kernel.org/linux-mm/20221114235507.294320-2-mike.kravetz@oracle.com/Link: https://lkml.kernel.org/r/20230104002732.232573-1-mike.kravetz@oracle.comSigned-off-by: Mike Kravetz Suggested-by: Peter Xu Acked-by: Michal Hocko Acked-by: Peter Xu Acked-by: Heiko Carstens [s390]Reviewed-by: Christoph Hellwig Cc: Christian Borntraeger Cc: Christian Brauner Cc: Dave Hansen Cc: David Hildenbrand Cc: Eric Dumazet Cc: Matthew Wilcox Cc: Michael Ellerman Cc: Nadav Amit Cc: Palmer Dabbelt Cc: Rik van Riel Cc: Vlastimil Babka Cc: Will Deacon Signed-off-by: Andrew Morton List of files: /linux-6.15/arch/arm64/kernel/vdso.c

d6c494e8 - vdso/timens: Refactor copy-pasted find_timens_vvar_page() helper into one copy

Wed, 30 Nov 2022 11:53:20 +0000

vdso/timens: Refactor copy-pasted find_timens_vvar_page() helper into one copyfind_timens_vvar_page() is not architecture-specific, as can be seen fromhow all five per-architecture versions of it are the same.(arm64, powerpc and riscv are exactly the same; x86 and s390 have twocharacters difference inside a comment, less blank lines, and mark the!CONFIG_TIME_NS version as inline.)Refactor the five copies into a central copy in kernel/time/namespace.c.Signed-off-by: Jann Horn Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20221130115320.2918447-1-jannh@google.com List of files: /linux-6.15/arch/arm64/kernel/vdso.c

de2b84d2 - arm64: remove mmap linked list from vdso

Tue, 06 Sep 2022 19:48:53 +0000

arm64: remove mmap linked list from vdsoUse the VMA iterator instead.Link: https://lkml.kernel.org/r/20220906194824.2110408-31-Liam.Howlett@oracle.comSigned-off-by: Matthew Wilcox (Oracle) Signed-off-by: Liam R. Howlett Acked-by: Vlastimil Babka Reviewed-by: Davidlohr Bueso Tested-by: Yu Zhao Cc: Catalin Marinas Cc: David Hildenbrand Cc: David Howells Cc: SeongJae Park Cc: Sven Schnelle Cc: Will Deacon Signed-off-by: Andrew Morton List of files: /linux-6.15/arch/arm64/kernel/vdso.c

4e3bca8f - arm64: alternative: patch alternatives in the vDSO

Tue, 30 Aug 2022 10:48:32 +0000

arm64: alternative: patch alternatives in the vDSOMake it possible to use alternatives in the vDSO, so that betterimplementations can be used if possible.Signed-off-by: Joey Gouly Cc: Will Deacon Cc: Vincenzo Frascino Cc: Mark Rutland Acked-by: Mark Rutland Link: https://lore.kernel.org/r/20220830104833.34636-3-joey.gouly@arm.comSigned-off-by: Catalin Marinas List of files: /linux-6.15/arch/arm64/kernel/vdso.c

a7dcf58a - arm64: Add __init section marker to some functions

Tue, 30 Mar 2021 05:54:49 +0000

arm64: Add __init section marker to some functionsThey are not needed after booting, so mark them as __init to move themto the .init section.Signed-off-by: Jisheng Zhang Reviewed-by: Steven Price Link: https://lore.kernel.org/r/20210330135449.4dcffd7f@xhacker.debianSigned-off-by: Catalin Marinas List of files: /linux-6.15/arch/arm64/kernel/vdso.c

6e554abd - arm64: compat: Poison the compat sigpage

Thu, 18 Mar 2021 17:07:38 +0000

arm64: compat: Poison the compat sigpageCommit 9c698bff66ab ("ARM: ensure the signal page contains defined contents")poisoned the unused portions of the signal page for 32-bit Arm.Implement the same poisoning for the compat signal page on arm64 ratherthan using __GFP_ZERO.Signed-off-by: Will Deacon Reviewed-by: Vincenzo Frascino Link: https://lore.kernel.org/r/20210318170738.7756-6-will@kernel.orgSigned-off-by: Catalin Marinas List of files: /linux-6.15/arch/arm64/kernel/vdso.c

7adbf10e - arm64: compat: Allow signal page to be remapped

Thu, 18 Mar 2021 17:07:36 +0000

arm64: compat: Allow signal page to be remappedFor compatability with 32-bit Arm, allow the compat signal page to beremapped via mremap().Signed-off-by: Will Deacon Reviewed-by: Vincenzo Frascino Link: https://lore.kernel.org/r/20210318170738.7756-4-will@kernel.orgSigned-off-by: Catalin Marinas List of files: /linux-6.15/arch/arm64/kernel/vdso.c

e9be47ea - arm64: vdso: Remove redundant calls to flush_dcache_page()

Thu, 18 Mar 2021 17:07:35 +0000

arm64: vdso: Remove redundant calls to flush_dcache_page()flush_dcache_page() ensures that the 'PG_dcache_clean' flag for its'page' argument is clear so that cache maintenance will be performedif the page is mapped into userspace with execute permissions.Newly allocated pages have this flag clear, so there is no need to callflush_dcache_page() for the compat vdso or signal pages. Remove theredundant calls.Signed-off-by: Will Deacon Reviewed-by: Vincenzo Frascino Link: https://lore.kernel.org/r/20210318170738.7756-3-will@kernel.orgSigned-off-by: Catalin Marinas List of files: /linux-6.15/arch/arm64/kernel/vdso.c

7cd6ca1d - arm64: vdso: Use GFP_KERNEL for allocating compat vdso and signal pages

Thu, 18 Mar 2021 17:07:34 +0000

arm64: vdso: Use GFP_KERNEL for allocating compat vdso and signal pagesThere's no need to allocate the compat vDSO and signal pages usingGFP_ATOMIC allocations, so use GFP_KERNEL instead.Signed-off-by: Will Deacon Reviewed-by: Vincenzo Frascino Link: https://lore.kernel.org/r/20210318170738.7756-2-will@kernel.orgSigned-off-by: Catalin Marinas List of files: /linux-6.15/arch/arm64/kernel/vdso.c

871402e0 - mm: forbid splitting special mappings

Tue, 15 Dec 2020 03:08:25 +0000

mm: forbid splitting special mappingsDon't allow splitting of vm_special_mapping's. It affects vdso/vvarareas. Uprobes have only one page in xol_area so they aren't affected.Those restrictions were enforced by checks in .mremap() callbacks.Restrict resizing with generic .split() callback.Link: https://lkml.kernel.org/r/20201013013416.390574-7-dima@arista.comSigned-off-by: Dmitry Safonov Cc: Alexander Viro Cc: Andy Lutomirski Cc: Brian Geffon Cc: Catalin Marinas Cc: Dan Carpenter Cc: Dan Williams Cc: Dave Jiang Cc: Hugh Dickins Cc: Ingo Molnar Cc: Jason Gunthorpe Cc: John Hubbard Cc: "Kirill A. Shutemov" Cc: Mike Kravetz Cc: Minchan Kim Cc: Ralph Campbell Cc: Russell King Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Vishal Verma Cc: Vlastimil Babka Cc: Will Deacon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds List of files: /linux-6.15/arch/arm64/kernel/vdso.c

2a30aca8 - arm64: vdso: Fix unusual formatting in *setup_additional_pages()

Mon, 22 Jun 2020 12:37:09 +0000

arm64: vdso: Fix unusual formatting in *setup_additional_pages()There's really no need to put every parameter on a new line when callinga function with a long name, so reformat the *setup_additional_pages()functions in the vDSO setup code to follow the usual conventions.Acked-by: Mark Rutland Reviewed-by: Vincenzo Frascino Reviewed-by: Ard Biesheuvel Signed-off-by: Will Deacon List of files: /linux-6.15/arch/arm64/kernel/vdso.c

0cbc2659 - arm64: vdso32: Remove a bunch of #ifdef CONFIG_COMPAT_VDSO guards

Mon, 22 Jun 2020 12:28:34 +0000

arm64: vdso32: Remove a bunch of #ifdef CONFIG_COMPAT_VDSO guardsMost of the compat vDSO code can be built and guarded using IS_ENABLED,so drop the unnecessary #ifdefs.Reviewed-by: Vincenzo Frascino Reviewed-by: Ard Biesheuvel Reviewed-by: Mark Rutland Signed-off-by: Will Deacon List of files: /linux-6.15/arch/arm64/kernel/vdso.c