kernel/linux.git/lib/crc, branch master

Merge tag 'loongarch-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson

2026-04-24T16:54:45+00:00

Pull LoongArch updates from Huacai Chen: - Adjust build infrastructure for 32BIT/64BIT - Add HIGHMEM (PKMAP and FIX_KMAP) support - Show and handle CPU vulnerabilites correctly - Batch the icache maintenance for jump_label - Add more atomic instructions support for BPF JIT - Add more features (e.g. fsession) support for BPF trampoline - Some bug fixes and other small changes * tag 'loongarch-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: (21 commits) selftests/bpf: Enable CAN_USE_LOAD_ACQ_STORE_REL for LoongArch LoongArch: BPF: Add fsession support for trampolines LoongArch: BPF: Introduce emit_store_stack_imm64() helper LoongArch: BPF: Support up to 12 function arguments for trampoline LoongArch: BPF: Support small struct arguments for trampoline LoongArch: BPF: Open code and remove invoke_bpf_mod_ret() LoongArch: BPF: Support load-acquire and store-release instructions LoongArch: BPF: Support 8 and 16 bit read-modify-write instructions LoongArch: BPF: Add the default case in emit_atomic() and rename it LoongArch: Define instruction formats for AM{SWAP/ADD}.{B/H} and DBAR LoongArch: Batch the icache maintenance for jump_label LoongArch: Add flush_icache_all()/local_flush_icache_all() LoongArch: Add spectre boundry for syscall dispatch table LoongArch: Show CPU vulnerabilites correctly LoongArch: Make arch_irq_work_has_interrupt() true only if IPI HW exist LoongArch: Use get_random_canary() for stack canary init LoongArch: Improve the logging of disabling KASLR LoongArch: Align FPU register state to 32 bytes LoongArch: Handle CONFIG_32BIT in syscall_get_arch() LoongArch: Add HIGHMEM (PKMAP and FIX_KMAP) support ...

LoongArch: Adjust build infrastructure for 32BIT/64BIT

2026-04-22T07:44:26+00:00

Adjust build infrastructure (Kconfig, Makefile and ld scripts) to let us enable both 32BIT/64BIT kernel build. Reviewed-by: Arnd Bergmann Signed-off-by: Jiaxun Yang Signed-off-by: Huacai Chen

lib/crc: arm64: Simplify intrinsics implementation

2026-04-02T23:14:53+00:00

NEON intrinsics are useful because they remove the need for manual register allocation, and the resulting code can be re-compiled and optimized for different micro-architectures, and shared between arm64 and 32-bit ARM. However, the strong typing of the vector variables can lead to incomprehensible gibberish, as is the case with the new CRC64 implementation. To address this, let's repaint all variables as uint64x2_t to minimize the number of vreinterpretq_xxx() calls, and to be able to rely on the ^ operator for exclusive OR operations. This makes the code much more concise and readable. While at it, wrap the calls to vmull_p64() et al in order to have a more consistent calling convention, and encapsulate any remaining vreinterpret() calls that are still needed. Signed-off-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20260330144630.33026-11-ardb@kernel.org Signed-off-by: Eric Biggers

lib/crc: arm64: Use existing macros for kernel-mode FPU cflags

2026-04-02T23:14:53+00:00

Use the existing CC_FPU_CFLAGS and CC_NO_FPU_CFLAGS to pass the appropriate compiler command line options for building kernel mode NEON intrinsics code. This is tidier, and will make it easier to reuse the code for 32-bit ARM. Signed-off-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20260330144630.33026-9-ardb@kernel.org Signed-off-by: Eric Biggers

lib/crc: arm64: Drop unnecessary chunking logic from crc64

2026-04-02T23:14:53+00:00

On arm64, kernel mode NEON executes with preemption enabled, so there is no need to chunk the input by hand. Signed-off-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20260330144630.33026-8-ardb@kernel.org Signed-off-by: Eric Biggers

lib/crc: arm64: Assume a little-endian kernel

2026-04-02T23:13:18+00:00

Since support for big-endian arm64 kernels was removed, the CPU_LE() macro now unconditionally emits the code it is passed, and the CPU_BE() macro now unconditionally discards the code it is passed. Simplify the assembly code in lib/crc/arm64/ accordingly. Reviewed-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20260401004431.151432-1-ebiggers@kernel.org Signed-off-by: Eric Biggers

lib/crc: arm64: add NEON accelerated CRC64-NVMe implementation

2026-03-29T20:22:13+00:00

Implement an optimized CRC64 (NVMe) algorithm for ARM64 using NEON Polynomial Multiply Long (PMULL) instructions. The generic shift-and-XOR software implementation is slow, which creates a bottleneck in NVMe and other storage subsystems. The acceleration is implemented using C intrinsics () rather than raw assembly for better readability and maintainability. Key highlights of this implementation: - Uses 4KB chunking inside scoped_ksimd() to avoid preemption latency spikes on large buffers. - Pre-calculates and loads fold constants via vld1q_u64() to minimize register spilling. - Benchmarks show the break-even point against the generic implementation is around 128 bytes. The PMULL path is enabled only for len >= 128. Performance results (kunit crc_benchmark on Cortex-A72): - Generic (len=4096): ~268 MB/s - PMULL (len=4096): ~1556 MB/s (nearly 6x improvement) Signed-off-by: Demian Shulhan Link: https://lore.kernel.org/r/20260329074338.1053550-1-demyansh@gmail.com Signed-off-by: Eric Biggers

lib/crc: arm64: Drop check for CONFIG_KERNEL_MODE_NEON

2026-03-17T16:29:28+00:00

CONFIG_KERNEL_MODE_NEON is always enabled on arm64, and it always has been since its introduction in 2013. Given that and the fact that the usefulness of kernel-mode NEON has only been increasing over time, checking for this option in arm64-specific code is unnecessary. Remove this check from lib/crc/ to simplify the code and prevent any future bugs where e.g. code gets disabled due to a typo in this logic. Acked-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20260314175744.30620-1-ebiggers@kernel.org Signed-off-by: Eric Biggers

lib/crc: tests: Add a .kunitconfig file

2026-03-09T20:29:47+00:00

Add a .kunitconfig file to the lib/crc/ directory so that the CRC library tests can be run more easily using kunit.py. Example with UML: tools/testing/kunit/kunit.py run --kunitconfig=lib/crc Example with QEMU: tools/testing/kunit/kunit.py run --kunitconfig=lib/crc --arch=arm64 --make_options LLVM=1 Link: https://lore.kernel.org/r/20260306033557.250499-4-ebiggers@kernel.org Signed-off-by: Eric Biggers

lib/crc: tests: Add CRC_ENABLE_ALL_FOR_KUNIT

2026-03-09T20:29:46+00:00

Now that crc_kunit uses the standard "depends on" pattern, enabling the full set of CRC tests is a bit difficult, mainly due to CRC7 being rarely used. Add a kconfig option to make it easier. It is visible only when KUNIT, so hopefully the extra prompt won't be too annoying. Link: https://lore.kernel.org/r/20260306033557.250499-3-ebiggers@kernel.org Signed-off-by: Eric Biggers