kernel/linux.git/arch/arm/include/asm/assembler.h, branch linux-5.9.y

Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm

2020-06-01T22:36:32+00:00

Pull ARM updates from Russell King: - remove a now unnecessary usage of the KERNEL_DS for sys_oabi_epoll_ctl() - update my email address in a number of drivers - decompressor EFI updates from Ard Biesheuvel - module unwind section handling updates - sparsemem Kconfig cleanups - make act_mm macro respect THREAD_SIZE * tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: ARM: 8980/1: Allow either FLATMEM or SPARSEMEM on the multiplatform build ARM: 8979/1: Remove redundant ARCH_SPARSEMEM_DEFAULT setting ARM: 8978/1: mm: make act_mm() respect THREAD_SIZE ARM: decompressor: run decompressor in place if loaded via UEFI ARM: decompressor: move GOT into .data for EFI enabled builds ARM: decompressor: defer loading of the contents of the LC0 structure ARM: decompressor: split off _edata and stack base into separate object ARM: decompressor: move headroom variable out of LC0 ARM: 8976/1: module: allow arch overrides for .init section names ARM: 8975/1: module: fix handling of unwind init sections ARM: 8974/1: use SPARSMEM_STATIC when SPARSEMEM is enabled ARM: 8971/1: replace the sole use of a symbol with its definition ARM: 8969/1: decompressor: simplify libfdt builds Update rmk's email address in various drivers ARM: compat: remove KERNEL_DS usage in sys_oabi_epoll_ctl()

ARM: uaccess: consolidate uaccess asm to asm/uaccess-asm.h

2020-05-03T16:30:24+00:00

Consolidate the user access assembly code to asm/uaccess-asm.h. This moves the csdb, check_uaccess, uaccess_mask_range_ptr, uaccess_enable, uaccess_disable, uaccess_save, uaccess_restore macros, and creates two new ones for exception entry and exit - uaccess_entry and uaccess_exit. This makes the uaccess_save and uaccess_restore macros private to asm/uaccess-asm.h. Signed-off-by: Russell King

ARM: 8971/1: replace the sole use of a symbol with its definition

2020-04-29T12:30:20+00:00

ALT_UP_B macro sets symbol up_b_offset via .equ to an expression involving another symbol. The macro gets expanded twice when arch/arm/kernel/sleep.S is assembled, creating a scenario where up_b_offset is set to another expression involving symbols while its current value is based on symbols. LLVM integrated assembler does not allow such cases, and based on the documentation of binutils, "Values that are based on expressions involving other symbols are allowed, but some targets may restrict this to only being done once per assembly", so it may be better to avoid such cases as it is not clearly stated which targets should support or disallow them. The fix in this case is simple, as up_b_offset has only one use, so we can replace the use with the definition and get rid of up_b_offset. Link:https://github.com/ClangBuiltLinux/linux/issues/920 Reviewed-by: Stefan Agner Reviewed-by: Nick Desaulniers Signed-off-by: Jian Cai Signed-off-by: Russell King

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

2019-06-19T15:09:55+00:00

Based on 2 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 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Enrico Weigelt Reviewed-by: Kate Stewart Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman

ARM: 8843/1: use unified assembler in headers

2019-02-26T11:26:06+00:00

Use unified assembler syntax (UAL) in headers. Divided syntax is considered deprecated. This will also allow to build the kernel using LLVM's integrated assembler. Signed-off-by: Stefan Agner Acked-by: Nicolas Pitre Signed-off-by: Russell King

ARM: 8812/1: Optimise copy_{from/to}_user for !CPU_USE_DOMAINS

2018-11-12T10:51:59+00:00

ARMv6+ processors do not use CONFIG_CPU_USE_DOMAINS and use privileged ldr/str instructions in copy_{from/to}_user. They are currently unnecessarily using single ldr/str instructions and can use ldm/stm instructions instead like memcpy does (but with appropriate fixup tables). This speeds up a "dd if=foo of=bar bs=32k" on a tmpfs filesystem by about 4% on my Cortex-A9. before:134217728 bytes (128.0MB) copied, 0.543848 seconds, 235.4MB/s before:134217728 bytes (128.0MB) copied, 0.538610 seconds, 237.6MB/s before:134217728 bytes (128.0MB) copied, 0.544356 seconds, 235.1MB/s before:134217728 bytes (128.0MB) copied, 0.544364 seconds, 235.1MB/s before:134217728 bytes (128.0MB) copied, 0.537130 seconds, 238.3MB/s before:134217728 bytes (128.0MB) copied, 0.533443 seconds, 240.0MB/s before:134217728 bytes (128.0MB) copied, 0.545691 seconds, 234.6MB/s before:134217728 bytes (128.0MB) copied, 0.534695 seconds, 239.4MB/s before:134217728 bytes (128.0MB) copied, 0.540561 seconds, 236.8MB/s before:134217728 bytes (128.0MB) copied, 0.541025 seconds, 236.6MB/s after:134217728 bytes (128.0MB) copied, 0.520445 seconds, 245.9MB/s after:134217728 bytes (128.0MB) copied, 0.527846 seconds, 242.5MB/s after:134217728 bytes (128.0MB) copied, 0.519510 seconds, 246.4MB/s after:134217728 bytes (128.0MB) copied, 0.527231 seconds, 242.8MB/s after:134217728 bytes (128.0MB) copied, 0.525030 seconds, 243.8MB/s after:134217728 bytes (128.0MB) copied, 0.524236 seconds, 244.2MB/s after:134217728 bytes (128.0MB) copied, 0.523659 seconds, 244.4MB/s after:134217728 bytes (128.0MB) copied, 0.525018 seconds, 243.8MB/s after:134217728 bytes (128.0MB) copied, 0.519249 seconds, 246.5MB/s after:134217728 bytes (128.0MB) copied, 0.518527 seconds, 246.9MB/s Reviewed-by: Nicolas Pitre Signed-off-by: Vincent Whitchurch Signed-off-by: Russell King

Merge branches 'fixes', 'misc' and 'spectre' into for-next

2018-10-10T12:53:33+00:00

ARM: 8796/1: spectre-v1,v1.1: provide helpers for address sanitization

2018-10-05T09:51:15+00:00

Introduce C and asm helpers to sanitize user address, taking the address range they target into account. Use asm helper for existing sanitization in __copy_from_user(). Signed-off-by: Julien Thierry Signed-off-by: Russell King

Merge branches 'fixes', 'misc' and 'spectre' into for-linus

2018-08-13T15:28:50+00:00

Conflicts: arch/arm/include/asm/uaccess.h Signed-off-by: Russell King

ARM: spectre-v1: mitigate user accesses

2018-08-02T16:41:38+00:00

Spectre variant 1 attacks are about this sequence of pseudo-code: index = load(user-manipulated pointer); access(base + index * stride); In order for the cache side-channel to work, the access() must me made to memory which userspace can detect whether cache lines have been loaded. On 32-bit ARM, this must be either user accessible memory, or a kernel mapping of that same user accessible memory. The problem occurs when the load() speculatively loads privileged data, and the subsequent access() is made to user accessible memory. Any load() which makes use of a user-maniplated pointer is a potential problem if the data it has loaded is used in a subsequent access. This also applies for the access() if the data loaded by that access is used by a subsequent access. Harden the get_user() accessors against Spectre attacks by forcing out of bounds addresses to a NULL pointer. This prevents get_user() being used as the load() step above. As a side effect, put_user() will also be affected even though it isn't implicated. Also harden copy_from_user() by redoing the bounds check within the arm_copy_from_user() code, and NULLing the pointer if out of bounds. Acked-by: Mark Rutland Signed-off-by: Russell King