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2019-08-15arm64: unexport set_memory_x and set_memory_nxChristoph Hellwig
No module currently messed with clearing or setting the execute permission of kernel memory, and none really should. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Will Deacon <will@kernel.org>
2019-07-12mm/pgtable: drop pgtable_t variable from pte_fn_t functionsAnshuman Khandual
Drop the pgtable_t variable from all implementation for pte_fn_t as none of them use it. apply_to_pte_range() should stop computing it as well. Should help us save some cycles. Link: http://lkml.kernel.org/r/1556803126-26596-1-git-send-email-anshuman.khandual@arm.com Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Acked-by: Matthew Wilcox <willy@infradead.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Logan Gunthorpe <logang@deltatee.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: <jglisse@redhat.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-08Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: - arm64 support for syscall emulation via PTRACE_SYSEMU{,_SINGLESTEP} - Wire up VM_FLUSH_RESET_PERMS for arm64, allowing the core code to manage the permissions of executable vmalloc regions more strictly - Slight performance improvement by keeping softirqs enabled while touching the FPSIMD/SVE state (kernel_neon_begin/end) - Expose a couple of ARMv8.5 features to user (HWCAP): CondM (new XAFLAG and AXFLAG instructions for floating point comparison flags manipulation) and FRINT (rounding floating point numbers to integers) - Re-instate ARM64_PSEUDO_NMI support which was previously marked as BROKEN due to some bugs (now fixed) - Improve parking of stopped CPUs and implement an arm64-specific panic_smp_self_stop() to avoid warning on not being able to stop secondary CPUs during panic - perf: enable the ARM Statistical Profiling Extensions (SPE) on ACPI platforms - perf: DDR performance monitor support for iMX8QXP - cache_line_size() can now be set from DT or ACPI/PPTT if provided to cope with a system cache info not exposed via the CPUID registers - Avoid warning on hardware cache line size greater than ARCH_DMA_MINALIGN if the system is fully coherent - arm64 do_page_fault() and hugetlb cleanups - Refactor set_pte_at() to avoid redundant READ_ONCE(*ptep) - Ignore ACPI 5.1 FADTs reported as 5.0 (infer from the 'arm_boot_flags' introduced in 5.1) - CONFIG_RANDOMIZE_BASE now enabled in defconfig - Allow the selection of ARM64_MODULE_PLTS, currently only done via RANDOMIZE_BASE (and an erratum workaround), allowing modules to spill over into the vmalloc area - Make ZONE_DMA32 configurable * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (54 commits) perf: arm_spe: Enable ACPI/Platform automatic module loading arm_pmu: acpi: spe: Add initial MADT/SPE probing ACPI/PPTT: Add function to return ACPI 6.3 Identical tokens ACPI/PPTT: Modify node flag detection to find last IDENTICAL x86/entry: Simplify _TIF_SYSCALL_EMU handling arm64: rename dump_instr as dump_kernel_instr arm64/mm: Drop [PTE|PMD]_TYPE_FAULT arm64: Implement panic_smp_self_stop() arm64: Improve parking of stopped CPUs arm64: Expose FRINT capabilities to userspace arm64: Expose ARMv8.5 CondM capability to userspace arm64: defconfig: enable CONFIG_RANDOMIZE_BASE arm64: ARM64_MODULES_PLTS must depend on MODULES arm64: bpf: do not allocate executable memory arm64/kprobes: set VM_FLUSH_RESET_PERMS on kprobe instruction pages arm64/mm: wire up CONFIG_ARCH_HAS_SET_DIRECT_MAP arm64: module: create module allocations without exec permissions arm64: Allow user selection of ARM64_MODULE_PLTS acpi/arm64: ignore 5.1 FADTs that are reported as 5.0 arm64: Allow selecting Pseudo-NMI again ...
2019-06-24arm64/mm: wire up CONFIG_ARCH_HAS_SET_DIRECT_MAPArd Biesheuvel
Wire up the special helper functions to manipulate aliases of vmalloc regions in the linear map. Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 284Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 and only version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 294 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141900.825281744@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-20arm64: mm: apply r/o permissions of VM areas to its linear alias as wellArd Biesheuvel
On arm64, we use block mappings and contiguous hints to map the linear region, to minimize the TLB footprint. However, this means that the entire region is mapped using read/write permissions, which we cannot modify at page granularity without having to take intrusive measures to prevent TLB conflicts. This means the linear aliases of pages belonging to read-only mappings (executable or otherwise) in the vmalloc region are also mapped read/write, and could potentially be abused to modify things like module code, bpf JIT code or other read-only data. So let's fix this, by extending the set_memory_ro/rw routines to take the linear alias into account. The consequence of enabling this is that we can no longer use block mappings or contiguous hints, so in cases where the TLB footprint of the linear region is a bottleneck, performance may be affected. Therefore, allow this feature to be runtime en/disabled, by setting rodata=full (or 'on' to disable just this enhancement, or 'off' to disable read-only mappings for code and r/o data entirely) on the kernel command line. Also, allow the default value to be set via a Kconfig option. Tested-by: Laura Abbott <labbott@redhat.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-11-20arm64: mm: purge lazily unmapped vm regions before changing permissionsArd Biesheuvel
Call vm_unmap_aliases() every time we apply any changes to permission attributes of mappings in the vmalloc region. This avoids any potential issues resulting from lingering writable or executable aliases of mappings that should be read-only or non-executable, respectively. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-02-16arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tablesWill Deacon
In many cases, page tables can be accessed concurrently by either another CPU (due to things like fast gup) or by the hardware page table walker itself, which may set access/dirty bits. In such cases, it is important to use READ_ONCE/WRITE_ONCE when accessing page table entries so that entries cannot be torn, merged or subject to apparent loss of coherence due to compiler transformations. Whilst there are some scenarios where this cannot happen (e.g. pinned kernel mappings for the linear region), the overhead of using READ_ONCE /WRITE_ONCE everywhere is minimal and makes the code an awful lot easier to reason about. This patch consistently uses these macros in the arch code, as well as explicitly namespacing pointers to page table entries from the entries themselves by using adopting a 'p' suffix for the former (as is sometimes used elsewhere in the kernel source). Tested-by: Yury Norov <ynorov@caviumnetworks.com> Tested-by: Richard Ruigrok <rruigrok@codeaurora.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-05-08arm64: use set_memory.h headerLaura Abbott
The set_memory_* functions have moved to set_memory.h. Use that header explicitly. Link: http://lkml.kernel.org/r/1488920133-27229-4-git-send-email-labbott@redhat.com Signed-off-by: Laura Abbott <labbott@redhat.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-04-05arm64: mm: add set_memory_valid()AKASHI Takahiro
This function validates and invalidates PTE entries, and will be utilized in kdump to protect loaded crash dump kernel image. Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-08-25arm64: hibernate: Support DEBUG_PAGEALLOCJames Morse
DEBUG_PAGEALLOC removes the valid bit of page table entries to prevent any access to unallocated memory. Hibernate uses this as a hint that those pages don't need to be saved/restored. This patch adds the kernel_page_present() function it uses. hibernate.c copies the resume kernel's linear map for use during restore. Add _copy_pte() to fill-in the holes made by DEBUG_PAGEALLOC in the resume kernel, so we can restore data the original kernel had at these addresses. Finally, DEBUG_PAGEALLOC means the linear-map alias of KERNEL_START to KERNEL_END may have holes in it, so we can't lazily clean this whole area to the PoC. Only clean the new mmuoff region, and the kernel/kvm idmaps. This reverts commit da24eb1f3f9e2c7b75c5f8c40d8e48e2c4789596. Reported-by: Will Deacon <will.deacon@arm.com> Signed-off-by: James Morse <james.morse@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-02-16arm64: Add support for ARCH_SUPPORTS_DEBUG_PAGEALLOCLaura Abbott
ARCH_SUPPORTS_DEBUG_PAGEALLOC provides a hook to map and unmap pages for debugging purposes. This requires memory be mapped with PAGE_SIZE mappings since breaking down larger mappings at runtime will lead to TLB conflicts. Check if debug_pagealloc is enabled at runtime and if so, map everyting with PAGE_SIZE pages. Implement the functions to actually map/unmap the pages at runtime. Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Laura Abbott <labbott@fedoraproject.org> [catalin.marinas@arm.com: static annotation block_mappings_allowed() and #ifdef] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-02arm64: allow vmalloc regions to be set with set_memory_*Ard Biesheuvel
The range of set_memory_* is currently restricted to the module address range because of difficulties in breaking down larger block sizes. vmalloc maps PAGE_SIZE pages so it is safe to use as well. Update the function ranges and add a comment explaining why the range is restricted the way it is. Suggested-by: Laura Abbott <labbott@fedoraproject.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-01-26arm64: mm: avoid calling apply_to_page_range on empty rangeMika Penttilä
Calling apply_to_page_range with an empty range results in a BUG_ON from the core code. This can be triggered by trying to load the st_drv module with CONFIG_DEBUG_SET_MODULE_RONX enabled: kernel BUG at mm/memory.c:1874! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP Modules linked in: CPU: 3 PID: 1764 Comm: insmod Not tainted 4.5.0-rc1+ #2 Hardware name: ARM Juno development board (r0) (DT) task: ffffffc9763b8000 ti: ffffffc975af8000 task.ti: ffffffc975af8000 PC is at apply_to_page_range+0x2cc/0x2d0 LR is at change_memory_common+0x80/0x108 This patch fixes the issue by making change_memory_common (called by the set_memory_* functions) a NOP when numpages == 0, therefore avoiding the erroneous call to apply_to_page_range and bringing us into line with x86 and s390. Cc: <stable@vger.kernel.org> Reviewed-by: Laura Abbott <labbott@redhat.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Mika Penttilä <mika.penttila@nextfour.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-10-28arm64/mm: use PAGE_ALIGNED instead of IS_ALIGNEDAlexander Kuleshov
The <linux/mm.h> already provides the PAGE_ALIGNED macro. Let's use this macro instead of IS_ALIGNED and passing PAGE_SIZE directly. Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com> Acked-by: Laura Abbott <laura@labbott.name> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-03-19arm64: mm: unexport set_memory_ro and set_memory_rwDaniel Borkmann
This effectively unexports set_memory_ro and set_memory_rw functions from commit 11d91a770f1f ("arm64: Add CONFIG_DEBUG_SET_MODULE_RONX support"). No module user of those is in mainline kernel and we explicitly do not want modules to use these functions, as they i.e. RO-protect eBPF (interpreted and JIT'ed) images from malicious modifications/bugs. Outside of eBPF scope, I believe also other set_memory_* functions should be unexported on arm64 due to non-existant mainline module user. Laura mentioned that they have some uses for modules doing set_memory_*, but none that are in mainline and it's unclear if they would ever get there. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Laura Abbott <lauraa@codeaurora.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-06arm64: Don't use is_module_addr in setting page attributesLaura Abbott
The set_memory_* functions currently only support module addresses. The addresses are validated using is_module_addr. That function is special though and relies on internal state in the module subsystem to work properly. At the time of module initialization and calling set_memory_*, it's too early for is_module_addr to work properly so it always returns false. Rather than be subject to the whims of the module state, just bounds check against the module virtual address range. Signed-off-by: Laura Abbott <lauraa@codeaurora.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-09-12arm64: pageattr: Correctly adjust unaligned start addressesLaura Abbott
The start address needs to be actually updated after it is detected to be unaligned. Adjust it and the end address properly. Reported-by: Zi Shen Lim <zlim.lnx@gmail.com> Reviewed-by: Zi Shen Lim <zlim.lnx@gmail.com> Signed-off-by: Laura Abbott <lauraa@codeaurora.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-09-08arm64: Add CONFIG_DEBUG_SET_MODULE_RONX supportLaura Abbott
In a similar fashion to other architecture, add the infrastructure and Kconfig to enable DEBUG_SET_MODULE_RONX support. When enabled, module ranges will be marked read-only/no-execute as appropriate. Signed-off-by: Laura Abbott <lauraa@codeaurora.org> [will: fixed off-by-one in module end check] Signed-off-by: Will Deacon <will.deacon@arm.com>