user/sven/linux.git/kernel/locking/lockdep.c, branch v5.15.87

lockdep: Fix -Wunused-parameter for _THIS_IP_

2022-09-20T10:39:42Z

[ Upstream commit 8b023accc8df70e72f7704d29fead7ca914d6837 ] While looking into a bug related to the compiler's handling of addresses of labels, I noticed some uses of _THIS_IP_ seemed unused in lockdep. Drive by cleanup. -Wunused-parameter: kernel/locking/lockdep.c:1383:22: warning: unused parameter 'ip' kernel/locking/lockdep.c:4246:48: warning: unused parameter 'ip' kernel/locking/lockdep.c:4844:19: warning: unused parameter 'ip' Signed-off-by: Nick Desaulniers Signed-off-by: Peter Zijlstra (Intel) Acked-by: Waiman Long Link: https://lore.kernel.org/r/20220314221909.2027027-1-ndesaulniers@google.com Stable-dep-of: 54c3931957f6 ("tracing: hold caller_addr to hardirq_{enable,disable}_ip") Signed-off-by: Sasha Levin

locking/lockdep: Fix lockdep_init_map_*() confusion

2022-08-17T12:23:08Z

[ Upstream commit eae6d58d67d9739be5f7ae2dbead1d0ef6528243 ] Commit dfd5e3f5fe27 ("locking/lockdep: Mark local_lock_t") added yet another lockdep_init_map_*() variant, but forgot to update all the existing users of the most complicated version. This could lead to a loss of lock_type and hence an incorrect report. Given the relative rarity of both local_lock and these annotations, this is unlikely to happen in practise, still, best fix things. Fixes: dfd5e3f5fe27 ("locking/lockdep: Mark local_lock_t") Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/YqyEDtoan20K0CVD@worktop.programming.kicks-ass.net Signed-off-by: Sasha Levin

locking/lockdep: Iterate lock_classes directly when reading lockdep files

2022-04-08T12:23:57Z

[ Upstream commit fb7275acd6fb988313dddd8d3d19efa70d9015ad ] When dumping lock_classes information via /proc/lockdep, we can't take the lockdep lock as the lock hold time is indeterminate. Iterating over all_lock_classes without holding lock can be dangerous as there is a slight chance that it may branch off to other lists leading to infinite loop or even access invalid memory if changes are made to all_lock_classes list in parallel. To avoid this problem, iteration of lock classes is now done directly on the lock_classes array itself. The lock_classes_in_use bitmap is checked to see if the lock class is being used. To avoid iterating the full array all the times, a new max_lock_class_idx value is added to track the maximum lock_class index that is currently being used. We can theoretically take the lockdep lock for iterating all_lock_classes when other lockdep files (lockdep_stats and lock_stat) are accessed as the lock hold time will be shorter for them. For consistency, they are also modified to iterate the lock_classes array directly. Signed-off-by: Waiman Long Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20220211035526.1329503-2-longman@redhat.com Signed-off-by: Sasha Levin

locking/lockdep: Avoid potential access of invalid memory in lock_class

2022-04-08T12:22:48Z

commit 61cc4534b6550997c97a03759ab46b29d44c0017 upstream. It was found that reading /proc/lockdep after a lockdep splat may potentially cause an access to freed memory if lockdep_unregister_key() is called after the splat but before access to /proc/lockdep [1]. This is due to the fact that graph_lock() call in lockdep_unregister_key() fails after the clearing of debug_locks by the splat process. After lockdep_unregister_key() is called, the lock_name may be freed but the corresponding lock_class structure still have a reference to it. That invalid memory pointer will then be accessed when /proc/lockdep is read by a user and a use-after-free (UAF) error will be reported if KASAN is enabled. To fix this problem, lockdep_unregister_key() is now modified to always search for a matching key irrespective of the debug_locks state and zap the corresponding lock class if a matching one is found. [1] https://lore.kernel.org/lkml/77f05c15-81b6-bddd-9650-80d5f23fe330@i-love.sakura.ne.jp/ Fixes: 8b39adbee805 ("locking/lockdep: Make lockdep_unregister_key() honor 'debug_locks' again") Reported-by: Tetsuo Handa Signed-off-by: Waiman Long Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Bart Van Assche Cc: Cheng-Jui Wang Link: https://lkml.kernel.org/r/20220103023558.1377055-1-longman@redhat.com Signed-off-by: Greg Kroah-Hartman

lockdep: Correct lock_classes index mapping

2022-02-23T11:03:22Z

commit 28df029d53a2fd80c1b8674d47895648ad26dcfb upstream. A kernel exception was hit when trying to dump /proc/lockdep_chains after lockdep report "BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!": Unable to handle kernel paging request at virtual address 00054005450e05c3 ... 00054005450e05c3] address between user and kernel address ranges ... pc : [0xffffffece769b3a8] string+0x50/0x10c lr : [0xffffffece769ac88] vsnprintf+0x468/0x69c ... Call trace: string+0x50/0x10c vsnprintf+0x468/0x69c seq_printf+0x8c/0xd8 print_name+0x64/0xf4 lc_show+0xb8/0x128 seq_read_iter+0x3cc/0x5fc proc_reg_read_iter+0xdc/0x1d4 The cause of the problem is the function lock_chain_get_class() will shift lock_classes index by 1, but the index don't need to be shifted anymore since commit 01bb6f0af992 ("locking/lockdep: Change the range of class_idx in held_lock struct") already change the index to start from 0. The lock_classes[-1] located at chain_hlocks array. When printing lock_classes[-1] after the chain_hlocks entries are modified, the exception happened. The output of lockdep_chains are incorrect due to this problem too. Fixes: f611e8cf98ec ("lockdep: Take read/write status in consideration when generate chainkey") Signed-off-by: Cheng Jui Wang Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Boqun Feng Link: https://lore.kernel.org/r/20220210105011.21712-1-cheng-jui.wang@mediatek.com Signed-off-by: Greg Kroah-Hartman

lockdep: Let lock_is_held_type() detect recursive read as read

2021-11-18T18:16:23Z

[ Upstream commit 2507003a1d10917c9158077bf6030719d02c941e ] lock_is_held_type(, 1) detects acquired read locks. It only recognized locks acquired with lock_acquire_shared(). Read locks acquired with lock_acquire_shared_recursive() are not recognized because a `2' is stored as the read value. Rework the check to additionally recognise lock's read value one and two as a read held lock. Fixes: e918188611f07 ("locking: More accurate annotations for read_lock()") Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Peter Zijlstra (Intel) Acked-by: Boqun Feng Acked-by: Waiman Long Link: https://lkml.kernel.org/r/20210903084001.lblecrvz4esl4mrr@linutronix.de Signed-off-by: Sasha Levin

locking/lockdep: Avoid RCU-induced noinstr fail

2021-11-18T18:16:09Z

[ Upstream commit ce0b9c805dd66d5e49fd53ec5415ae398f4c56e6 ] vmlinux.o: warning: objtool: look_up_lock_class()+0xc7: call to rcu_read_lock_any_held() leaves .noinstr.text section Signed-off-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/20210624095148.311980536@infradead.org Signed-off-by: Sasha Levin

Merge branch 'core-rcu-2021.07.04' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu

2021-07-04T19:58:33Z

Pull RCU updates from Paul McKenney: - Bitmap parsing support for "all" as an alias for all bits - Documentation updates - Miscellaneous fixes, including some that overlap into mm and lockdep - kvfree_rcu() updates - mem_dump_obj() updates, with acks from one of the slab-allocator maintainers - RCU NOCB CPU updates, including limited deoffloading - SRCU updates - Tasks-RCU updates - Torture-test updates * 'core-rcu-2021.07.04' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: (78 commits) tasks-rcu: Make show_rcu_tasks_gp_kthreads() be static inline rcu-tasks: Make ksoftirqd provide RCU Tasks quiescent states rcu: Add missing __releases() annotation rcu: Remove obsolete rcu_read_unlock() deadlock commentary rcu: Improve comments describing RCU read-side critical sections rcu: Create an unrcu_pointer() to remove __rcu from a pointer srcu: Early test SRCU polling start rcu: Fix various typos in comments rcu/nocb: Unify timers rcu/nocb: Prepare for fine-grained deferred wakeup rcu/nocb: Only cancel nocb timer if not polling rcu/nocb: Delete bypass_timer upon nocb_gp wakeup rcu/nocb: Cancel nocb_timer upon nocb_gp wakeup rcu/nocb: Allow de-offloading rdp leader rcu/nocb: Directly call __wake_nocb_gp() from bypass timer rcu: Don't penalize priority boosting when there is nothing to boost rcu: Point to documentation of ordering guarantees rcu: Make rcu_gp_cleanup() be noinline for tracing rcu: Restrict RCU_STRICT_GRACE_PERIOD to at most four CPUs rcu: Make show_rcu_gp_kthreads() dump rcu_node structures blocking GP ...

Merge tag 'sched-core-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2021-06-28T19:14:19Z

Pull scheduler udpates from Ingo Molnar: - Changes to core scheduling facilities: - Add "Core Scheduling" via CONFIG_SCHED_CORE=y, which enables coordinated scheduling across SMT siblings. This is a much requested feature for cloud computing platforms, to allow the flexible utilization of SMT siblings, without exposing untrusted domains to information leaks & side channels, plus to ensure more deterministic computing performance on SMT systems used by heterogenous workloads. There are new prctls to set core scheduling groups, which allows more flexible management of workloads that can share siblings. - Fix task->state access anti-patterns that may result in missed wakeups and rename it to ->__state in the process to catch new abuses. - Load-balancing changes: - Tweak newidle_balance for fair-sched, to improve 'memcache'-like workloads. - "Age" (decay) average idle time, to better track & improve workloads such as 'tbench'. - Fix & improve energy-aware (EAS) balancing logic & metrics. - Fix & improve the uclamp metrics. - Fix task migration (taskset) corner case on !CONFIG_CPUSET. - Fix RT and deadline utilization tracking across policy changes - Introduce a "burstable" CFS controller via cgroups, which allows bursty CPU-bound workloads to borrow a bit against their future quota to improve overall latencies & batching. Can be tweaked via /sys/fs/cgroup/cpu//cpu.cfs_burst_us. - Rework assymetric topology/capacity detection & handling. - Scheduler statistics & tooling: - Disable delayacct by default, but add a sysctl to enable it at runtime if tooling needs it. Use static keys and other optimizations to make it more palatable. - Use sched_clock() in delayacct, instead of ktime_get_ns(). - Misc cleanups and fixes. * tag 'sched-core-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (72 commits) sched/doc: Update the CPU capacity asymmetry bits sched/topology: Rework CPU capacity asymmetry detection sched/core: Introduce SD_ASYM_CPUCAPACITY_FULL sched_domain flag psi: Fix race between psi_trigger_create/destroy sched/fair: Introduce the burstable CFS controller sched/uclamp: Fix uclamp_tg_restrict() sched/rt: Fix Deadline utilization tracking during policy change sched/rt: Fix RT utilization tracking during policy change sched: Change task_struct::state sched,arch: Remove unused TASK_STATE offsets sched,timer: Use __set_current_state() sched: Add get_current_state() sched,perf,kvm: Fix preemption condition sched: Introduce task_is_running() sched: Unbreak wakeups sched/fair: Age the average idle time sched/cpufreq: Consider reduced CPU capacity in energy calculation sched/fair: Take thermal pressure into account while estimating energy thermal/cpufreq_cooling: Update offline CPUs per-cpu thermal_pressure sched/fair: Return early from update_tg_cfs_load() if delta == 0 ...

Merge tag 'locking-core-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2021-06-28T18:45:29Z

Pull locking updates from Ingo Molnar: - Core locking & atomics: - Convert all architectures to ARCH_ATOMIC: move every architecture to ARCH_ATOMIC, then get rid of ARCH_ATOMIC and all the transitory facilities and #ifdefs. Much reduction in complexity from that series: 63 files changed, 756 insertions(+), 4094 deletions(-) - Self-test enhancements - Futexes: - Add the new FUTEX_LOCK_PI2 ABI, which is a variant that doesn't set FLAGS_CLOCKRT (.e. uses CLOCK_MONOTONIC). [ The temptation to repurpose FUTEX_LOCK_PI's implicit setting of FLAGS_CLOCKRT & invert the flag's meaning to avoid having to introduce a new variant was resisted successfully. ] - Enhance futex self-tests - Lockdep: - Fix dependency path printouts - Optimize trace saving - Broaden & fix wait-context checks - Misc cleanups and fixes. * tag 'locking-core-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits) locking/lockdep: Correct the description error for check_redundant() futex: Provide FUTEX_LOCK_PI2 to support clock selection futex: Prepare futex_lock_pi() for runtime clock selection lockdep/selftest: Remove wait-type RCU_CALLBACK tests lockdep/selftests: Fix selftests vs PROVE_RAW_LOCK_NESTING lockdep: Fix wait-type for empty stack locking/selftests: Add a selftest for check_irq_usage() lockding/lockdep: Avoid to find wrong lock dep path in check_irq_usage() locking/lockdep: Remove the unnecessary trace saving locking/lockdep: Fix the dep path printing for backwards BFS selftests: futex: Add futex compare requeue test selftests: futex: Add futex wait test seqlock: Remove trailing semicolon in macros locking/lockdep: Reduce LOCKDEP dependency list locking/lockdep,doc: Improve readability of the block matrix locking/atomics: atomic-instrumented: simplify ifdeffery locking/atomic: delete !ARCH_ATOMIC remnants locking/atomic: xtensa: move to ARCH_ATOMIC locking/atomic: sparc: move to ARCH_ATOMIC locking/atomic: sh: move to ARCH_ATOMIC ...