linux-rng/include/asm-generic, branch master

Merge tag 'core-rseq-2025-11-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2025-12-02T16:48:53Z

Pull rseq updates from Thomas Gleixner: "A large overhaul of the restartable sequences and CID management: The recent enablement of RSEQ in glibc resulted in regressions which are caused by the related overhead. It turned out that the decision to invoke the exit to user work was not really a decision. More or less each context switch caused that. There is a long list of small issues which sums up nicely and results in a 3-4% regression in I/O benchmarks. The other detail which caused issues due to extra work in context switch and task migration is the CID (memory context ID) management. It also requires to use a task work to consolidate the CID space, which is executed in the context of an arbitrary task and results in sporadic uncontrolled exit latencies. The rewrite addresses this by: - Removing deprecated and long unsupported functionality - Moving the related data into dedicated data structures which are optimized for fast path processing. - Caching values so actual decisions can be made - Replacing the current implementation with a optimized inlined variant. - Separating fast and slow path for architectures which use the generic entry code, so that only fault and error handling goes into the TIF_NOTIFY_RESUME handler. - Rewriting the CID management so that it becomes mostly invisible in the context switch path. That moves the work of switching modes into the fork/exit path, which is a reasonable tradeoff. That work is only required when a process creates more threads than the cpuset it is allowed to run on or when enough threads exit after that. An artificial thread pool benchmarks which triggers this did not degrade, it actually improved significantly. The main effect in migration heavy scenarios is that runqueue lock held time and therefore contention goes down significantly" * tag 'core-rseq-2025-11-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits) sched/mmcid: Switch over to the new mechanism sched/mmcid: Implement deferred mode change irqwork: Move data struct to a types header sched/mmcid: Provide CID ownership mode fixup functions sched/mmcid: Provide new scheduler CID mechanism sched/mmcid: Introduce per task/CPU ownership infrastructure sched/mmcid: Serialize sched_mm_cid_fork()/exit() with a mutex sched/mmcid: Provide precomputed maximal value sched/mmcid: Move initialization out of line signal: Move MMCID exit out of sighand lock sched/mmcid: Convert mm CID mask to a bitmap cpumask: Cache num_possible_cpus() sched/mmcid: Use cpumask_weighted_or() cpumask: Introduce cpumask_weighted_or() sched/mmcid: Prevent pointless work in mm_update_cpus_allowed() sched/mmcid: Move scheduler code out of global header sched: Fixup whitespace damage sched/mmcid: Cacheline align MM CID storage sched/mmcid: Use proper data structures sched/mmcid: Revert the complex CID management ...

Merge tag 'core-bugs-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2025-12-02T05:33:01Z

Pull bug handling infrastructure updates from Ingo Molnar: "Core updates: - Improve WARN(), which has vararg printf like arguments, to work with the x86 #UD based WARN-optimizing infrastructure by hiding the format in the bug_table and replacing this first argument with the address of the bug-table entry, while making the actual function that's called a UD1 instruction (Peter Zijlstra) - Introduce the CONFIG_DEBUG_BUGVERBOSE_DETAILED Kconfig switch (Ingo Molnar, s390 support by Heiko Carstens) Fixes and cleanups: - bugs/s390: Remove private WARN_ON() implementation (Heiko Carstens) - : Make i386 use GENERIC_BUG_RELATIVE_POINTERS (Peter Zijlstra)" * tag 'core-bugs-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (31 commits) x86/bugs: Make i386 use GENERIC_BUG_RELATIVE_POINTERS x86/bug: Fix BUG_FORMAT vs KASLR x86_64/bug: Inline the UD1 x86/bug: Implement WARN_ONCE() x86_64/bug: Implement __WARN_printf() x86/bug: Use BUG_FORMAT for DEBUG_BUGVERBOSE_DETAILED x86/bug: Add BUG_FORMAT basics bug: Allow architectures to provide __WARN_printf() bug: Implement WARN_ON() using __WARN_FLAGS() bug: Add report_bug_entry() bug: Add BUG_FORMAT_ARGS infrastructure bug: Clean up CONFIG_GENERIC_BUG_RELATIVE_POINTERS bug: Add BUG_FORMAT infrastructure x86: Rework __bug_table helpers bugs/s390: Remove private WARN_ON() implementation bugs/core: Reorganize fields in the first line of WARNING output, add ->comm[] output bugs/sh: Concatenate 'cond_str' with '__FILE__' in __WARN_FLAGS(), to extend WARN_ON/BUG_ON output bugs/parisc: Concatenate 'cond_str' with '__FILE__' in __WARN_FLAGS(), to extend WARN_ON/BUG_ON output bugs/riscv: Concatenate 'cond_str' with '__FILE__' in __BUG_FLAGS(), to extend WARN_ON/BUG_ON output bugs/riscv: Pass in 'cond_str' to __BUG_FLAGS() ...

Merge tag 'objtool-core-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2025-12-02T04:18:59Z

Pull objtool updates from Ingo Molnar: - klp-build livepatch module generation (Josh Poimboeuf) Introduce new objtool features and a klp-build script to generate livepatch modules using a source .patch as input. This builds on concepts from the longstanding out-of-tree kpatch project which began in 2012 and has been used for many years to generate livepatch modules for production kernels. However, this is a complete rewrite which incorporates hard-earned lessons from 12+ years of maintaining kpatch. Key improvements compared to kpatch-build: - Integrated with objtool: Leverages objtool's existing control-flow graph analysis to help detect changed functions. - Works on vmlinux.o: Supports late-linked objects, making it compatible with LTO, IBT, and similar. - Simplified code base: ~3k fewer lines of code. - Upstream: No more out-of-tree #ifdef hacks, far less cruft. - Cleaner internals: Vastly simplified logic for symbol/section/reloc inclusion and special section extraction. - Robust __LINE__ macro handling: Avoids false positive binary diffs caused by the __LINE__ macro by introducing a fix-patch-lines script which injects #line directives into the source .patch to preserve the original line numbers at compile time. - Disassemble code with libopcodes instead of running objdump (Alexandre Chartre) - Disassemble support (-d option to objtool) by Alexandre Chartre, which supports the decoding of various Linux kernel code generation specials such as alternatives: 17ef: sched_balance_find_dst_group+0x62f mov 0x34(%r9),%edx 17f3: sched_balance_find_dst_group+0x633 | | X86_FEATURE_POPCNT 17f3: sched_balance_find_dst_group+0x633 | call 0x17f8 <__sw_hweight64> | popcnt %rdi,%rax 17f8: sched_balance_find_dst_group+0x638 cmp %eax,%edx ... jump table alternatives: 1895: sched_use_asym_prio+0x5 test $0x8,%ch 1898: sched_use_asym_prio+0x8 je 0x18a9 189a: sched_use_asym_prio+0xa | | JUMP 189a: sched_use_asym_prio+0xa | jmp 0x18ae | nop2 189c: sched_use_asym_prio+0xc mov $0x1,%eax 18a1: sched_use_asym_prio+0x11 and $0x80,%ecx ... exception table alternatives: native_read_msr: 5b80: native_read_msr+0x0 mov %edi,%ecx 5b82: native_read_msr+0x2 | | EXCEPTION 5b82: native_read_msr+0x2 | rdmsr | resume at 0x5b84 5b84: native_read_msr+0x4 shl $0x20,%rdx .... x86 feature flag decoding (also see the X86_FEATURE_POPCNT example in sched_balance_find_dst_group() above): 2faaf: start_thread_common.constprop.0+0x1f jne 0x2fba4 2fab5: start_thread_common.constprop.0+0x25 | | X86_FEATURE_ALWAYS | X86_BUG_NULL_SEG 2fab5: start_thread_common.constprop.0+0x25 | jmp 0x2faba <.altinstr_aux+0x2f4> | jmp 0x4b0 | nop5 2faba: start_thread_common.constprop.0+0x2a mov $0x2b,%eax ... NOP sequence shortening: 1048e2: snapshot_write_finalize+0xc2 je 0x104917 1048e4: snapshot_write_finalize+0xc4 nop6 1048ea: snapshot_write_finalize+0xca nop11 1048f5: snapshot_write_finalize+0xd5 nop11 104900: snapshot_write_finalize+0xe0 mov %rax,%rcx 104903: snapshot_write_finalize+0xe3 mov 0x10(%rdx),%rax ... and much more. - Function validation tracing support (Alexandre Chartre) - Various -ffunction-sections fixes (Josh Poimboeuf) - Clang AutoFDO (Automated Feedback-Directed Optimizations) support (Josh Poimboeuf) - Misc fixes and cleanups (Borislav Petkov, Chen Ni, Dylan Hatch, Ingo Molnar, John Wang, Josh Poimboeuf, Pankaj Raghav, Peter Zijlstra, Thorsten Blum) * tag 'objtool-core-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (129 commits) objtool: Fix segfault on unknown alternatives objtool: Build with disassembly can fail when including bdf.h objtool: Trim trailing NOPs in alternative objtool: Add wide output for disassembly objtool: Compact output for alternatives with one instruction objtool: Improve naming of group alternatives objtool: Add Function to get the name of a CPU feature objtool: Provide access to feature and flags of group alternatives objtool: Fix address references in alternatives objtool: Disassemble jump table alternatives objtool: Disassemble exception table alternatives objtool: Print addresses with alternative instructions objtool: Disassemble group alternatives objtool: Print headers for alternatives objtool: Preserve alternatives order objtool: Add the --disas= action objtool: Do not validate IBT for .return_sites and .call_sites objtool: Improve tracing of alternative instructions objtool: Add functions to better name alternatives objtool: Identify the different types of alternatives ...

Merge tag 'vfs-6.19-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2025-12-01T16:44:26Z

Pull misc vfs updates from Christian Brauner: "Features: - Cheaper MAY_EXEC handling for path lookup. This elides MAY_WRITE permission checks during path lookup and adds the IOP_FASTPERM_MAY_EXEC flag so filesystems like btrfs can avoid expensive permission work. - Hide dentry_cache behind runtime const machinery. - Add German Maglione as virtiofs co-maintainer. Cleanups: - Tidy up and inline step_into() and walk_component() for improved code generation. - Re-enable IOCB_NOWAIT writes to files. This refactors file timestamp update logic, fixing a layering bypass in btrfs when updating timestamps on device files and improving FMODE_NOCMTIME handling in VFS now that nfsd started using it. - Path lookup optimizations extracting slowpaths into dedicated routines and adding branch prediction hints for mntput_no_expire(), fd_install(), lookup_slow(), and various other hot paths. - Enable clang's -fms-extensions flag, requiring a JFS rename to avoid conflicts. - Remove spurious exports in fs/file_attr.c. - Stop duplicating union pipe_index declaration. This depends on the shared kbuild branch that brings in -fms-extensions support which is merged into this branch. - Use MD5 library instead of crypto_shash in ecryptfs. - Use largest_zero_folio() in iomap_dio_zero(). - Replace simple_strtol/strtoul with kstrtoint/kstrtouint in init and initrd code. - Various typo fixes. Fixes: - Fix emergency sync for btrfs. Btrfs requires an explicit sync_fs() call with wait == 1 to commit super blocks. The emergency sync path never passed this, leaving btrfs data uncommitted during emergency sync. - Use local kmap in watch_queue's post_one_notification(). - Add hint prints in sb_set_blocksize() for LBS dependency on THP" * tag 'vfs-6.19-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (35 commits) MAINTAINERS: add German Maglione as virtiofs co-maintainer fs: inline step_into() and walk_component() fs: tidy up step_into() & friends before inlining orangefs: use inode_update_timestamps directly btrfs: fix the comment on btrfs_update_time btrfs: use vfs_utimes to update file timestamps fs: export vfs_utimes fs: lift the FMODE_NOCMTIME check into file_update_time_flags fs: refactor file timestamp update logic include/linux/fs.h: trivial fix: regualr -> regular fs/splice.c: trivial fix: pipes -> pipe's fs: mark lookup_slow() as noinline fs: add predicts based on nd->depth fs: move mntput_no_expire() slowpath into a dedicated routine fs: remove spurious exports in fs/file_attr.c watch_queue: Use local kmap in post_one_notification() fs: touch up predicts in path lookup fs: move fd_install() slowpath into a dedicated routine and provide commentary fs: hide dentry_cache behind runtime const machinery fs: touch predicts in do_dentry_open() ...

x86/bug: Implement WARN_ONCE()

2025-11-24T19:23:25Z

Implement WARN_ONCE like WARN using BUGFLAG_ONCE. Signed-off-by: Peter Zijlstra (Intel) Link: https://patch.msgid.link/20251110115758.339309119@infradead.org

x86/bug: Use BUG_FORMAT for DEBUG_BUGVERBOSE_DETAILED

2025-11-24T19:22:21Z

Since we have an explicit format string, use it for the condition string instead of frobbing it in the file string. Signed-off-by: Peter Zijlstra (Intel) Link: https://patch.msgid.link/20251110115758.097401406@infradead.org

bug: Allow architectures to provide __WARN_printf()

2025-11-21T10:21:32Z

In addition to providing __WARN_FLAGS(), allow an architecture to also provide __WARN_printf(). Signed-off-by: Peter Zijlstra (Intel) Link: https://patch.msgid.link/20251110115757.807154591@infradead.org

bug: Implement WARN_ON() using __WARN_FLAGS()

2025-11-21T10:21:32Z

This completes 3bc3c9c3ab6d ("bugs/core: Pass down the condition string of WARN_ON_ONCE(cond) warnings to __WARN_FLAGS()") and makes WARN_ON() and WARN_ON_ONCE() behaviour consistent. Signed-off-by: Peter Zijlstra (Intel) Link: https://patch.msgid.link/20251110115757.690999560@infradead.org

bug: Add BUG_FORMAT_ARGS infrastructure

2025-11-21T10:21:31Z

Add BUG_FORMAT_ARGS; when an architecture is able to provide a va_list given pt_regs, use this to print format arguments. Signed-off-by: Peter Zijlstra (Intel) Link: https://patch.msgid.link/20251110115757.457339417@infradead.org

bug: Clean up CONFIG_GENERIC_BUG_RELATIVE_POINTERS

2025-11-21T10:21:31Z

Three repeated CONFIG_GENERIC_BUG_RELATIVE_POINTERS #ifdefs right after one another yields unreadable code. Add a helper. Signed-off-by: Peter Zijlstra (Intel) Link: https://patch.msgid.link/20251110115757.341703850@infradead.org