kernel.git/arch/s390/lib, branch linux-6.15.y

Merge tag 's390-6.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

2025-03-29T18:59:43Z

Pull s390 updates from Vasily Gorbik: - Add sorting of mcount locations at build time - Rework uaccess functions with C exception handling to shorten inline assembly size and enable full inlining. This yields near-optimal code for small constant copies with a ~40kb kernel size increase - Add support for a configurable STRICT_MM_TYPECHECKS which allows to generate better code, but also allows to have type checking for debug builds - Optimize get_lowcore() for common callers with alternatives that nearly revert to the pre-relocated lowcore code, while also slightly reducing syscall entry and exit time - Convert MACHINE_HAS_* checks for single facility tests into cpu_has_* style macros that call test_facility(), and for features with additional conditions, add a new ALT_TYPE_FEATURE alternative to provide a static branch via alternative patching. Also, move machine feature detection to the decompressor for early patching and add debugging functionality to easily show which alternatives are patched - Add exception table support to early boot / startup code to get rid of the open coded exception handling - Use asm_inline for all inline assemblies with EX_TABLE or ALTERNATIVE to ensure correct inlining and unrolling decisions - Remove 2k page table leftovers now that s390 has been switched to always allocate 4k page tables - Split kfence pool into 4k mappings in arch_kfence_init_pool() and remove the architecture-specific kfence_split_mapping() - Use READ_ONCE_NOCHECK() in regs_get_kernel_stack_nth() to silence spurious KASAN warnings from opportunistic ftrace argument tracing - Force __atomic_add_const() variants on s390 to always return void, ensuring compile errors for improper usage - Remove s390's ioremap_wt() and pgprot_writethrough() due to mismatched semantics and lack of known users, relying on asm-generic fallbacks - Signal eventfd in vfio-ap to notify userspace when the guest AP configuration changes, including during mdev removal - Convert mdev_types from an array to a pointer in vfio-ccw and vfio-ap drivers to avoid fake flex array confusion - Cleanup trap code - Remove references to the outdated linux390@de.ibm.com address - Other various small fixes and improvements all over the code * tag 's390-6.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (78 commits) s390: Use inline qualifier for all EX_TABLE and ALTERNATIVE inline assemblies s390/kfence: Split kfence pool into 4k mappings in arch_kfence_init_pool() s390/ptrace: Avoid KASAN false positives in regs_get_kernel_stack_nth() s390/boot: Ignore vmlinux.map s390/sysctl: Remove "vm/allocate_pgste" sysctl s390: Remove 2k vs 4k page table leftovers s390/tlb: Use mm_has_pgste() instead of mm_alloc_pgste() s390/lowcore: Use lghi instead llilh to clear register s390/syscall: Merge __do_syscall() and do_syscall() s390/spinlock: Implement SPINLOCK_LOCKVAL with inline assembly s390/smp: Implement raw_smp_processor_id() with inline assembly s390/current: Implement current with inline assembly s390/lowcore: Use inline qualifier for get_lowcore() inline assembly s390: Move s390 sysctls into their own file under arch/s390 s390/syscall: Simplify syscall_get_arguments() s390/vfio-ap: Notify userspace that guest's AP config changed when mdev removed s390: Remove ioremap_wt() and pgprot_writethrough() s390/mm: Add configurable STRICT_MM_TYPECHECKS s390/mm: Convert pgste_val() into function s390/mm: Convert pgprot_val() into function ...

s390/spinlock: Implement SPINLOCK_LOCKVAL with inline assembly

2025-03-18T16:13:04Z

Implement SPINLOCK_LOCKVAL with an inline assembly, which makes use of the ALTERNATIVE macro, to read spinlock_lockval from lowcore. Provide an alternative instruction with a different offset in case lowcore is relocated. This replaces sequences of two instructions with one instruction. Before: 10602a: a7 78 00 00 lhi %r7,0 10602e: a5 8e 00 00 llilh %r8,0 106032: 58 d0 83 ac l %r13,940(%r8) 106036: ba 7d b5 80 cs %r7,%r13,1408(%r11) After: 10602a: a7 88 00 00 lhi %r8,0 10602e: e3 70 03 ac 00 58 ly %r7,940 106034: ba 87 b5 80 cs %r8,%r7,1408(%r11) Kernel image size change: add/remove: 756/750 grow/shrink: 646/3435 up/down: 30778/-46326 (-15548) Acked-by: Vasily Gorbik Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390: Move s390 sysctls into their own file under arch/s390

2025-03-18T16:13:04Z

Move s390 sysctls (spin_retry and userprocess_debug) into their own files under arch/s390. Create two new sysctl tables (2390_{fault,spin}_sysctl_table) which will be initialized with arch_initcall placing them after their original place in proc_root_init. This is part of a greater effort to move ctl tables into their respective subsystems which will reduce the merge conflicts in kernel/sysctl.c. Signed-off-by: joel granados Acked-by: Heiko Carstens Link: https://lore.kernel.org/r/20250306-jag-mv_ctltables-v2-6-71b243c8d3f8@kernel.org Signed-off-by: Vasily Gorbik

s390: Convert MACHINE_IS_[LPAR|VM|KVM], etc, machine_is_[lpar|vm|kvm]()

2025-03-04T16:18:07Z

Move machine type detection to the decompressor and use static branches to implement and use machine_is_[lpar|vm|kvm]() instead of a runtime check via MACHINE_IS_[LPAR|VM|KVM]. Reviewed-by: Vasily Gorbik Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390/uaccess: Inline __clear_user()

2025-03-04T16:18:04Z

Rework __clear_user() similar to raw_copy_from_user() / raw_copy_to_user() and inline the function saving the overhead of branches. Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390/uaccess: Separate key uaccess functions

2025-03-04T16:18:03Z

Implement separate raw_copy_to_user_key() and raw_copy_from_user_key() functions, which allows to remove the open-coded operand access control handling from the normal raw_copy_to_user() / raw_copy_from_user() functions - they are simplified to use immediate instructions to load hard-coded operand access control values into register zero, which saves one instruction. Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik

lib/crc32: remove "_le" from crc32c base and arch functions

2025-02-09T04:06:30Z

Following the standardization on crc32c() as the lib entry point for the Castagnoli CRC32 instead of the previous mix of crc32c(), crc32c_le(), and __crc32c_le(), make the same change to the underlying base and arch functions that implement it. Reviewed-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20250208024911.14936-7-ebiggers@kernel.org Signed-off-by: Eric Biggers

Merge tag 's390-6.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

2025-01-30T18:48:17Z

Pull more s390 updates from Alexander Gordeev: - The rework that uncoupled physical and virtual address spaces inadvertently prevented KASAN shadow mappings from using large pages. Restore large page mappings for KASAN shadows - Add decompressor routine physmem_alloc() that may fail, unlike physmem_alloc_or_die(). This allows callers to implement fallback paths - Allow falling back from large pages to smaller pages (1MB or 4KB) if the allocation of 2GB pages in the decompressor can not be fulfilled - Add to the decompressor boot print support of "%%" format string, width and padding hadnling, length modifiers and decimal conversion specifiers - Add to the decompressor message severity levels similar to kernel ones. Support command-line options that control console output verbosity - Replaces boot_printk() calls with appropriate loglevel- specific helpers such as boot_emerg(), boot_warn(), and boot_debug(). - Collect all boot messages into a ring buffer independent of the current log level. This is particularly useful for early crash analysis - If 'earlyprintk' command line parameter is not specified, store decompressor boot messages in a ring buffer to be printed later by the kernel, once the console driver is registered - Add 'bootdebug' command line parameter to enable printing of decompressor debug messages when needed. That parameters allows message suppressing and filtering - Dump boot messages on a decompressor crash, but only if 'bootdebug' command line parameter is enabled - When CONFIG_PRINTK_TIME is enabled, add timestamps to boot messages in the same format as regular printk() - Dump physical memory tracking information on boot: online ranges, reserved areas and vmem allocations - Dump virtual memory layout and randomization details - Improve decompression error reporting and dump the message ring buffer in case the boot failed and system halted - Add an exception handler which handles exceptions when FPU control register is attempted to be set to an invalid value. Remove '.fixup' section as result of this change - Use 'A', 'O', and 'R' inline assembly format flags, which allows recent Clang compilers to generate better FPU code - Rework uaccess code so it reads better and generates more efficient code - Cleanup futex inline assembly code - Disable KMSAN instrumention for futex inline assemblies, which contain dereferenced user pointers. Otherwise, shadows for the user pointers would be accessed - PFs which are not initially configured but in standby create only a single-function PCI domain. If they are configured later on, sibling PFs and their child VFs will not be added to their PCI domain breaking SR-IOV expectations. Fix that by allowing initially configured but in standby PFs create multi-function PCI domains - Add '-std=gnu11' to decompressor and purgatory CFLAGS to avoid compile errors caused by kernel's own definitions of 'bool', 'false', and 'true' conflicting with the C23 reserved keywords - Fix sclp subsystem failure when a sclp console is not present - Fix misuse of non-NULL terminated strings in vmlogrdr driver - Various other small improvements, cleanups and fixes * tag 's390-6.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (53 commits) s390/vmlogrdr: Use array instead of string initializer s390/vmlogrdr: Use internal_name for error messages s390/sclp: Initialize sclp subsystem via arch_cpu_finalize_init() s390/tools: Use array instead of string initializer s390/vmem: Fix null-pointer-arithmetic warning in vmem_map_init() s390: Add '-std=gnu11' to decompressor and purgatory CFLAGS s390/bitops: Use correct constraint for arch_test_bit() inline assembly s390/pci: Fix SR-IOV for PFs initially in standby s390/futex: Avoid KMSAN instrumention for user pointers s390/uaccess: Rename get_put_user_noinstr_attributes to uaccess_kmsan_or_inline s390/futex: Cleanup futex_atomic_cmpxchg_inatomic() s390/futex: Generate futex atomic op functions s390/uaccess: Remove INLINE_COPY_FROM_USER and INLINE_COPY_TO_USER s390/uaccess: Use asm goto for put_user()/get_user() s390/uaccess: Remove usage of the oac specifier s390/uaccess: Replace EX_TABLE_UA_LOAD_MEM exception handling s390/uaccess: Cleanup noinstr __put_user()/__get_user() inline assembly constraints s390/uaccess: Remove __put_user_fn()/__get_user_fn() wrappers s390/uaccess: Move put_user() / __put_user() close to put_user() asm code s390/uaccess: Use asm goto for __mvc_kernel_nofault() ...

s390/uaccess: Remove INLINE_COPY_FROM_USER and INLINE_COPY_TO_USER

2025-01-26T16:24:07Z

The s390 implementations of raw_copy_from_user() and raw_copy_to_user() are never inlined. However INLINE_COPY_FROM_USER and INLINE_COPY_TO_USER are still set. This leads to the odd situation that only the error handling (memset to zero of the not copied bytes) of copy_from_user() is inlined, while the actual fast path code is out-of-line. This would make sense if raw_copy_from_user() and raw_copy_to_user() were implemented in assembler files, where inlining is not possible. But the current s390 setup does not make any sense. Address this by moving the raw uaccess copy inline assemblies to the uaccess header file, and remove INLINE_COPY_FROM_USER and INLINE_COPY_TO_USER definitions. This way the uaccess code, but now including error handling, is still out-of-line with the common code _copy_from_user() and _copy_to_user() variants, which inline the raw uaccess functions via _inline_copy_from_user() and _inline_copy_to_user(). This reduces the size of the kernel image by ~17kb. (defconfig, gcc 14.2.0) Acked-by: Alexander Gordeev Signed-off-by: Heiko Carstens Signed-off-by: Alexander Gordeev

Merge tag 'crc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux

2025-01-23T03:55:08Z

Pull CRC updates from Eric Biggers: - Reorganize the architecture-optimized CRC32 and CRC-T10DIF code to be directly accessible via the library API, instead of requiring the crypto API. This is much simpler and more efficient. - Convert some users such as ext4 to use the CRC32 library API instead of the crypto API. More conversions like this will come later. - Add a KUnit test that tests and benchmarks multiple CRC variants. Remove older, less-comprehensive tests that are made redundant by this. - Add an entry to MAINTAINERS for the kernel's CRC library code. I'm volunteering to maintain it. I have additional cleanups and optimizations planned for future cycles. * tag 'crc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux: (31 commits) MAINTAINERS: add entry for CRC library powerpc/crc: delete obsolete crc-vpmsum_test.c lib/crc32test: delete obsolete crc32test.c lib/crc16_kunit: delete obsolete crc16_kunit.c lib/crc_kunit.c: add KUnit test suite for CRC library functions powerpc/crc-t10dif: expose CRC-T10DIF function through lib arm64/crc-t10dif: expose CRC-T10DIF function through lib arm/crc-t10dif: expose CRC-T10DIF function through lib x86/crc-t10dif: expose CRC-T10DIF function through lib crypto: crct10dif - expose arch-optimized lib function lib/crc-t10dif: add support for arch overrides lib/crc-t10dif: stop wrapping the crypto API scsi: target: iscsi: switch to using the crc32c library f2fs: switch to using the crc32 library jbd2: switch to using the crc32c library ext4: switch to using the crc32c library lib/crc32: make crc32c() go directly to lib bcachefs: Explicitly select CRYPTO from BCACHEFS_FS x86/crc32: expose CRC32 functions through lib x86/crc32: update prototype for crc32_pclmul_le_16() ...