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

s390: Add z17 elf platform

2025-04-09T10:12:41Z

Add detection for machine types 0x9175 and 0x9176 and set ELF platform name to z17. Reviewed-by: Heiko Carstens Signed-off-by: Vasily Gorbik Signed-off-by: Heiko Carstens

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/tx: Convert MACHINE_HAS_TE to machine_has_tx()

2025-03-04T16:18:06Z

Use static branch(es) to implement and use machine_has_tx() instead of a runtime check with MACHINE_HAS_TE. Reviewed-by: Vasily Gorbik Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390/pci: Get rid of MACHINE_HAS_PCI_MIO

2025-03-04T16:18:06Z

Remove MACHINE_FLAG_PCI_MIO/MACHINE_HAS_PCI_MIO and implement the identical functionality with set_machine_feature(), clear_machine_feature() and test_machine_feature(). Acked-by: Niklas Schnelle Tested-by: Niklas Schnelle Reviewed-by: Vasily Gorbik Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390/cpufeature: Convert MACHINE_HAS_EDAT1 to cpu_has_edat1()

2025-03-04T16:18:05Z

Convert MACHINE_HAS_... to cpu_has_...() which uses test_facility() instead of testing the machine_flags lowcore member if the feature is present. test_facility() generates better code since it results in a static branch without accessing memory. The branch is patched via alternatives by the decompressor depending on the availability of the required facility. Reviewed-by: Vasily Gorbik Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390/cpufeature: Convert MACHINE_HAS_GS to cpu_has_gs()

2025-03-04T16:18:04Z

s390: switch stop_machine_yield() to using cpumask_next_wrap()

2025-02-24T21:37:23Z

Calling cpumask_next_wrap_old() with starting CPU equal to wrapping CPU effectively means the request to find next CPU, wrapping around if needed. cpumask_next_wrap() is the proper replacement for that. Signed-off-by: Yury Norov

cpumask: deprecate cpumask_next_wrap()

2025-02-24T21:37:22Z

The next patch aligns implementation of cpumask_next_wrap() with the find_next_bit_wrap(), and it changes function signature. To make the transition smooth, this patch deprecates current implementation by adding an _old suffix. The following patches switch current users to the new implementation one by one. No functional changes were intended. Signed-off-by: Yury Norov

s390/alternatives: Move text sync functions

2024-07-23T14:02:31Z

Move all text sync functions from alternative.c to processor.c. This way there is only minimal code left in alternative.c left, which is a prerequisite to use the C file within boot code as well. Reviewed-by: Alexander Gordeev Tested-by: Sven Schnelle Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390/fpu: get rid of MACHINE_HAS_VX

2023-12-11T13:33:07Z

Get rid of MACHINE_HAS_VX and replace it with cpu_has_vx() which is a short readable wrapper for "test_facility(129)". Facility bit 129 is set if the vector facility is present. test_facility() returns also true for all bits which are set in the architecture level set of the cpu that the kernel is compiled for. This means that test_facility(129) is a compile time constant which returns true for z13 and later, since the vector facility bit is part of the z13 kernel ALS. In result the compiled code will have less runtime checks, and less code. Reviewed-by: Hendrik Brueckner Signed-off-by: Heiko Carstens Signed-off-by: Alexander Gordeev