user/sven/linux.git/kernel/locking, branch v6.12.8

Merge tag 'locking-urgent-2024-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2024-09-29T15:51:30Z

Pull locking updates from Ingo Molnar: "lockdep: - Fix potential deadlock between lockdep and RCU (Zhiguo Niu) - Use str_plural() to address Coccinelle warning (Thorsten Blum) - Add debuggability enhancement (Luis Claudio R. Goncalves) static keys & calls: - Fix static_key_slow_dec() yet again (Peter Zijlstra) - Handle module init failure correctly in static_call_del_module() (Thomas Gleixner) - Replace pointless WARN_ON() in static_call_module_notify() (Thomas Gleixner) : - Add usage and style documentation (Dan Williams) rwsems: - Move is_rwsem_reader_owned() and rwsem_owner() under CONFIG_DEBUG_RWSEMS (Waiman Long) atomic ops, x86: - Redeclare x86_32 arch_atomic64_{add,sub}() as void (Uros Bizjak) - Introduce the read64_nonatomic macro to x86_32 with cx8 (Uros Bizjak)" Signed-off-by: Ingo Molnar * tag 'locking-urgent-2024-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/rwsem: Move is_rwsem_reader_owned() and rwsem_owner() under CONFIG_DEBUG_RWSEMS jump_label: Fix static_key_slow_dec() yet again static_call: Replace pointless WARN_ON() in static_call_module_notify() static_call: Handle module init failure correctly in static_call_del_module() locking/lockdep: Simplify character output in seq_line() lockdep: fix deadlock issue between lockdep and rcu lockdep: Use str_plural() to fix Coccinelle warning cleanup: Add usage and style documentation lockdep: suggest the fix for "lockdep bfs error:-1" on print_bfs_bug locking/atomic/x86: Redeclare x86_32 arch_atomic64_{add,sub}() as void locking/atomic/x86: Introduce the read64_nonatomic macro to x86_32 with cx8

Merge branch 'locking/core' into locking/urgent, to pick up pending commits

2024-09-29T06:57:18Z

Merge all pending locking commits into a single branch. Signed-off-by: Ingo Molnar

Merge tag 'mm-nonmm-stable-2024-09-21-07-52' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2024-09-21T15:20:50Z

Pull non-MM updates from Andrew Morton: "Many singleton patches - please see the various changelogs for details. Quite a lot of nilfs2 work this time around. Notable patch series in this pull request are: - "mul_u64_u64_div_u64: new implementation" by Nicolas Pitre, with assistance from Uwe Kleine-König. Reimplement mul_u64_u64_div_u64() to provide (much) more accurate results. The current implementation was causing Uwe some issues in the PWM drivers. - "xz: Updates to license, filters, and compression options" from Lasse Collin. Miscellaneous maintenance and kinor feature work to the xz decompressor. - "Fix some GDB command error and add some GDB commands" from Kuan-Ying Lee. Fixes and enhancements to the gdb scripts. - "treewide: add missing MODULE_DESCRIPTION() macros" from Jeff Johnson. Adds lots of MODULE_DESCRIPTIONs, thus fixing lots of warnings about this. - "nilfs2: add support for some common ioctls" from Ryusuke Konishi. Adds various commonly-available ioctls to nilfs2. - "This series fixes a number of formatting issues in kernel doc comments" from Ryusuke Konishi does that. - "nilfs2: prevent unexpected ENOENT propagation" from Ryusuke Konishi. Fix issues where -ENOENT was being unintentionally and inappropriately returned to userspace. - "nilfs2: assorted cleanups" from Huang Xiaojia. - "nilfs2: fix potential issues with empty b-tree nodes" from Ryusuke Konishi fixes some issues which can occur on corrupted nilfs2 filesystems. - "scripts/decode_stacktrace.sh: improve error reporting and usability" from Luca Ceresoli does those things" * tag 'mm-nonmm-stable-2024-09-21-07-52' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (103 commits) list: test: increase coverage of list_test_list_replace*() list: test: fix tests for list_cut_position() proc: use __auto_type more treewide: correct the typo 'retun' ocfs2: cleanup return value and mlog in ocfs2_global_read_info() nilfs2: remove duplicate 'unlikely()' usage nilfs2: fix potential oob read in nilfs_btree_check_delete() nilfs2: determine empty node blocks as corrupted nilfs2: fix potential null-ptr-deref in nilfs_btree_insert() user_namespace: use kmemdup_array() instead of kmemdup() for multiple allocation tools/mm: rm thp_swap_allocator_test when make clean squashfs: fix percpu address space issues in decompressor_multi_percpu.c lib: glob.c: added null check for character class nilfs2: refactor nilfs_segctor_thread() nilfs2: use kthread_create and kthread_stop for the log writer thread nilfs2: remove sc_timer_task nilfs2: do not repair reserved inode bitmap in nilfs_new_inode() nilfs2: eliminate the shared counter and spinlock for i_generation nilfs2: separate inode type information from i_state field nilfs2: use the BITS_PER_LONG macro ...

Merge tag 'sched-core-2024-09-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2024-09-19T13:55:58Z

Pull scheduler updates from Ingo Molnar: - Implement the SCHED_DEADLINE server infrastructure - Daniel Bristot de Oliveira's last major contribution to the kernel: "SCHED_DEADLINE servers can help fixing starvation issues of low priority tasks (e.g., SCHED_OTHER) when higher priority tasks monopolize CPU cycles. Today we have RT Throttling; DEADLINE servers should be able to replace and improve that." (Daniel Bristot de Oliveira, Peter Zijlstra, Joel Fernandes, Youssef Esmat, Huang Shijie) - Preparatory changes for sched_ext integration: - Use set_next_task(.first) where required - Fix up set_next_task() implementations - Clean up DL server vs. core sched - Split up put_prev_task_balance() - Rework pick_next_task() - Combine the last put_prev_task() and the first set_next_task() - Rework dl_server - Add put_prev_task(.next) (Peter Zijlstra, with a fix by Tejun Heo) - Complete the EEVDF transition and refine EEVDF scheduling: - Implement delayed dequeue - Allow shorter slices to wakeup-preempt - Use sched_attr::sched_runtime to set request/slice suggestion - Document the new feature flags - Remove unused and duplicate-functionality fields - Simplify & unify pick_next_task_fair() - Misc debuggability enhancements (Peter Zijlstra, with fixes/cleanups by Dietmar Eggemann, Valentin Schneider and Chuyi Zhou) - Initialize the vruntime of a new task when it is first enqueued, resulting in significant decrease in latency of newly woken tasks (Zhang Qiao) - Introduce SM_IDLE and an idle re-entry fast-path in __schedule() (K Prateek Nayak, Peter Zijlstra) - Clean up and clarify the usage of Clean up usage of rt_task() (Qais Yousef) - Preempt SCHED_IDLE entities in strict cgroup hierarchies (Tianchen Ding) - Clarify the documentation of time units for deadline scheduler parameters (Christian Loehle) - Remove the HZ_BW chicken-bit feature flag introduced a year ago, the original change seems to be working fine (Phil Auld) - Misc fixes and cleanups (Chen Yu, Dan Carpenter, Huang Shijie, Peilin He, Qais Yousefm and Vincent Guittot) * tag 'sched-core-2024-09-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (64 commits) sched/cpufreq: Use NSEC_PER_MSEC for deadline task cpufreq/cppc: Use NSEC_PER_MSEC for deadline task sched/deadline: Clarify nanoseconds in uapi sched/deadline: Convert schedtool example to chrt sched/debug: Fix the runnable tasks output sched: Fix sched_delayed vs sched_core kernel/sched: Fix util_est accounting for DELAY_DEQUEUE kthread: Fix task state in kthread worker if being frozen sched/pelt: Use rq_clock_task() for hw_pressure sched/fair: Move effective_cpu_util() and effective_cpu_util() in fair.c sched/core: Introduce SM_IDLE and an idle re-entry fast-path in __schedule() sched: Add put_prev_task(.next) sched: Rework dl_server sched: Combine the last put_prev_task() and the first set_next_task() sched: Rework pick_next_task() sched: Split up put_prev_task_balance() sched: Clean up DL server vs core sched sched: Fixup set_next_task() implementations sched: Use set_next_task(.first) where required sched/fair: Properly deactivate sched_delayed task upon class change ...

Merge tag 'printk-for-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux

2024-09-17T06:52:28Z

Pull printk updates from Petr Mladek: "This is the "last" part of the support for the new nbcon consoles. Where "nbcon" stays for "No Big console lock CONsoles" aka not under the console_lock. New callbacks are added to struct console: - write_thread() for flushing nbcon consoles in task context. - write_atomic() for flushing nbcon consoles in atomic context, including NMI. - con->device_lock() and device_unlock() for taking the driver specific lock, for example, port->lock. New printk-specific kthreads are created: - per-console kthreads which get responsible for flushing normal priority messages on nbcon consoles. - thread which gets responsible for flushing normal priority messages on all consoles when CONFIG_RT enabled. The new callbacks are called under a special per-console lock which has already been added back in v6.7. It allows to distinguish three severities: normal, emergency, and panic. A context with a higher priority could take over the ownership when it is safe even in the middle of handling a record. The panic context could do it even when it is not safe. But it is allowed only for the final desperate flush before entering the infinite loop. The new lock helps to flush the messages directly in emergency and panic contexts. But it is not enough in all situations: - console_lock() is still need for synchronization against boot consoles. - con->device_lock() is need for synchronization against other operations on the same HW, e.g. serial port speed setting, non-printk related read/write. The dependency on con->device_lock() is mutual. Any code taking the driver specific lock has to acquire the related nbcon console context as well. For example, see the new uart_port_lock() API. It provides the necessary synchronization against emergency and panic contexts where the messages are flushed only under the new per-console lock. Maybe surprisingly, a quite tricky part is the decision how to flush the consoles in various situations. It has to take into account: - message priority: normal, emergency, panic - scheduling context: task, atomic, deferred_legacy - registered consoles: boot, legacy, nbcon - threads are running: early boot, suspend, shutdown, panic - caller: printk(), pr_flush(), printk_flush_in_panic(), console_unlock(), console_start(), ... The primary decision is made in printk_get_console_flush_type(). It creates a hint what the caller should do: - flush nbcon consoles directly or via the kthread - call the legacy loop (console_unlock()) directly or via irq_work The existing behavior is preserved for the legacy consoles. The only exception is that they are not longer flushed directly from printk() in panic() before CPUs are stopped. But this blocking happens only when at least one nbcon console is registered. The motivation is to increase a chance to produce the crash dump. They legacy consoles might create a deadlock in compare with nbcon consoles. The nbcon console should allow to see the messages even when the crash dump fails. There are three possible ways how nbcon consoles are flushed: - The per-nbcon-console kthread is responsible for flushing messages added with the normal priority. This is the default mode. - The legacy loop, aka console_unlock(), is used when there is still a boot console registered. There is no easy way how to match an early console driver with a nbcon console driver. And the console_lock() provides the only reliable serialization at the moment. The legacy loop uses either con->write_atomic() or con->write_thread() callbacks depending on whether it is allowed to schedule. The atomic variant has to be used from printk(). - In other situations, the messages are flushed directly using write_atomic() which can be called in any context, including NMI. It is primary needed during early boot or shutdown, in emergency situations, and panic. The emergency priority is used by a code called within nbcon_cpu_emergency_enter()/exit(). At the moment, it is used in four situations: WARN(), Oops, lockdep, and RCU stall reports. Finally, there is no nbcon console at the moment. It means that the changes should _not_ modify the existing behavior. The only exception is CONFIG_RT which would force offloading the legacy loop, for normal priority context, into the dedicated kthread" * tag 'printk-for-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux: (54 commits) printk: Avoid false positive lockdep report for legacy printing printk: nbcon: Assign nice -20 for printing threads printk: Implement legacy printer kthread for PREEMPT_RT tty: sysfs: Add nbcon support for 'active' proc: Add nbcon support for /proc/consoles proc: consoles: Add notation to c_start/c_stop printk: nbcon: Show replay message on takeover printk: Provide helper for message prepending printk: nbcon: Rely on kthreads for normal operation printk: nbcon: Use thread callback if in task context for legacy printk: nbcon: Relocate nbcon_atomic_emit_one() printk: nbcon: Introduce printer kthreads printk: nbcon: Init @nbcon_seq to highest possible printk: nbcon: Add context to usable() and emit() printk: Flush console on unregister_console() printk: Fail pr_flush() if before SYSTEM_SCHEDULING printk: nbcon: Add function for printers to reacquire ownership printk: nbcon: Use raw_cpu_ptr() instead of open coding printk: Use the BITS_PER_LONG macro lockdep: Mark emergency sections in lockdep splats ...

locking/rwsem: Move is_rwsem_reader_owned() and rwsem_owner() under CONFIG_DEBUG_RWSEMS

2024-09-10T10:02:33Z

Both is_rwsem_reader_owned() and rwsem_owner() are currently only used when CONFIG_DEBUG_RWSEMS is defined. This causes a compilation error with clang when `make W=1` and CONFIG_WERROR=y: kernel/locking/rwsem.c:187:20: error: unused function 'is_rwsem_reader_owned' [-Werror,-Wunused-function] 187 | static inline bool is_rwsem_reader_owned(struct rw_semaphore *sem) | ^~~~~~~~~~~~~~~~~~~~~ kernel/locking/rwsem.c:271:35: error: unused function 'rwsem_owner' [-Werror,-Wunused-function] 271 | static inline struct task_struct *rwsem_owner(struct rw_semaphore *sem) | ^~~~~~~~~~~ Fix this by moving these two functions under the CONFIG_DEBUG_RWSEMS define. Reported-by: Andy Shevchenko Signed-off-by: Waiman Long Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Andy Shevchenko Tested-by: Andy Shevchenko Link: https://lore.kernel.org/r/20240909182905.161156-1-longman@redhat.com

locking/ww_mutex/test: add MODULE_DESCRIPTION()

2024-09-02T03:43:31Z

Fix the 'make W=1' warning: WARNING: modpost: missing MODULE_DESCRIPTION() in kernel/locking/test-ww_mutex.o Link: https://lkml.kernel.org/r/20240730-module_description_orphans-v1-5-7094088076c8@quicinc.com Signed-off-by: Jeff Johnson Acked-by: Waiman Long Cc: Alexandre Torgue Cc: Alistar Popple Cc: Andrew Jeffery Cc: Andy Lutomirski Cc: Arnd Bergmann Cc: Boqun Feng Cc: Borislav Petkov Cc: Christophe Leroy Cc: Dave Hansen Cc: Eddie James Cc: Greg Kroah-Hartman Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: Jeremy Kerr Cc: Joel Stanley Cc: Karol Herbst Cc: Masami Hiramatsu Cc: Maxime Coquelin Cc: Michael Ellerman Cc: Naveen N Rao Cc: Nicholas Piggin Cc: Nouveau Cc: Pekka Paalanen Cc: Peter Zijlstra Cc: Rafael J. Wysocki Cc: Russell King Cc: Steven Rostedt (Google) Cc: Thomas Gleixner Cc: Viresh Kumar Cc: Will Deacon Signed-off-by: Andrew Morton

lockdep: Mark emergency sections in lockdep splats

2024-08-21T13:03:04Z

Mark emergency sections wherever multiple lines of lock debugging output are generated. In an emergency section, every printk() call will attempt to directly flush to the consoles using the EMERGENCY priority. Note that debug_show_all_locks() and lockdep_print_held_locks() rely on their callers to enter the emergency section. This is because these functions can also be called in non-emergency situations (such as sysrq). Signed-off-by: John Ogness Reviewed-by: Petr Mladek Link: https://lore.kernel.org/r/20240820063001.36405-36-john.ogness@linutronix.de Signed-off-by: Petr Mladek

rtmutex: Drop rt_mutex::wait_lock before scheduling

2024-08-15T13:38:53Z

rt_mutex_handle_deadlock() is called with rt_mutex::wait_lock held. In the good case it returns with the lock held and in the deadlock case it emits a warning and goes into an endless scheduling loop with the lock held, which triggers the 'scheduling in atomic' warning. Unlock rt_mutex::wait_lock in the dead lock case before issuing the warning and dropping into the schedule for ever loop. [ tglx: Moved unlock before the WARN(), removed the pointless comment, massaged changelog, added Fixes tag ] Fixes: 3d5c9340d194 ("rtmutex: Handle deadlock detection smarter") Signed-off-by: Roland Xu Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/ME0P300MB063599BEF0743B8FA339C2CECC802@ME0P300MB0635.AUSP300.PROD.OUTLOOK.COM

Merge tag 'bcachefs-2024-08-08' of git://evilpiepirate.org/bcachefs

2024-08-08T20:27:31Z

Pull bcachefs fixes from Kent Overstreet: "Assorted little stuff: - lockdep fixup for lockdep_set_notrack_class() - we can now remove a device when using erasure coding without deadlocking, though we still hit other issues - the 'allocator stuck' timeout is now configurable, and messages are ratelimited. The default timeout has been increased from 10 seconds to 30" * tag 'bcachefs-2024-08-08' of git://evilpiepirate.org/bcachefs: bcachefs: Use bch2_wait_on_allocator() in btree node alloc path bcachefs: Make allocator stuck timeout configurable, ratelimit messages bcachefs: Add missing path_traverse() to btree_iter_next_node() bcachefs: ec should not allocate from ro devs bcachefs: Improved allocator debugging for ec bcachefs: Add missing bch2_trans_begin() call bcachefs: Add a comment for bucket helper types bcachefs: Don't rely on implicit unsigned -> signed integer conversion lockdep: Fix lockdep_set_notrack_class() for CONFIG_LOCK_STAT bcachefs: Fix double free of ca->buckets_nouse