Hello, Linus, The following changes since commit fe15c26ee26efa11741a7b632e9f23b01aca4cc6: Linux 6.3-rc1 (2023-03-05 14:52:03 -0800) are available in the Git repository at: git://git.kernel.org/pub/scm/linux/kernel/git/jfern/linux.git tags/rcu.6.4.april5.2023.3 for you to fetch changes up to 8ae99857748bece993962dd8d04e096f9e76731f: Merge branches 'rcu/staging-core', 'rcu/staging-docs' and 'rcu/staging-kfree', remote-tracking branches 'paul/srcu-cf.2023.04.04a', 'fbq/rcu/lockdep.2023.03.27a' and 'fbq/rcu/rcutorture.2023.03.20a' into rcu/staging (2023-04-05 13:50:37 +0000) Highlights of RCU changes for 6.4 include: 1. Updates and additions to MAINTAINERS files, with Boqun being added to the RCU entry and Zqiang being added as an RCU reviewer. I have also transitioned from reviewer to maintainer; however, Paul will be taking over sending RCU pull-requests for the next merge window. 2. Resolution of hotplug warning in nohz code, achieved by fixing cpu_is_hotpluggable() through interaction with the nohz subsystem. Tick dependency modifications by Zqiang, focusing on fixing usage of the TICK_DEP_BIT_RCU_EXP bitmask. 3. Avoid needless calls to the rcu-lazy shrinker for CONFIG_RCU_LAZY=n kernels, fixed by Zqiang. 4. Improvements to rcu-tasks stall reporting by Neeraj. 5. Initial renaming of k[v]free_rcu() to k[v]free_rcu_mightsleep() for increased robustness, affecting several components like mac802154, drbd, vmw_vmci, tracing, and more. A report [1] by Eric Dumazet showed that the API could be unknowingly used in an atomic context, so we'd rather make sure they know what they're asking for by being explicit: [1] https://lore.kernel.org/all/20221202052847.2623997-1-edumazet@xxxxxxxxxx/ 6. Documentation updates, including corrections to spelling, clarifications in comments, and improvements to the srcu_size_state comments. 7. Better srcu_struct cache locality for readers, by adjusting the size of srcu_struct in support of SRCU usage by Christoph Hellwig. 8. Teach lockdep to detect deadlocks between srcu_read_lock() vs synchronize_srcu() contributed by Boqun. Previously lockdep could not detect such deadlocks, now it can. 9. Integration of rcutorture and rcu-related tools, targeted for v6.4 from Boqun's tree, featuring new SRCU deadlock scenarios, test_nmis module parameter, and more. 10. Miscellaneous changes, various code cleanups and comment improvements. Thank you for considering these RCU updates for the 6.4 release. ---------------------------------------------------------------- Bhaskar Chowdhury (1): tools: rcu: Add usage function and check for argument Boqun Feng (5): locking/lockdep: Introduce lock_sync() rcu: Annotate SRCU's update-side lockdep dependencies locking: Reduce the number of locks in ww_mutex stress tests locking/lockdep: Improve the deadlock scenario print for sync and read lock MAINTAINERS: Add Boqun to RCU entry Frederic Weisbecker (1): rcu: Further comment and explain the state space of GP sequences Joel Fernandes (Google) (7): srcu: Clarify comments on memory barrier "E" MAINTAINERS: Change Joel Fernandes from R: to M: MAINTAINERS: Add Zqiang as a RCU reviewer tick/nohz: Fix cpu_is_hotpluggable() by checking with nohz subsystem mac802154: Rename kfree_rcu() to kvfree_rcu_mightsleep() checkpatch: Error out if deprecated RCU API used Merge branches 'rcu/staging-core', 'rcu/staging-docs' and 'rcu/staging-kfree', remote-tracking branches 'paul/srcu-cf.2023.04.04a', 'fbq/rcu/lockdep.2023.03.27a' and 'fbq/rcu/rcutorture.2023.03.20a' into rcu/staging Neeraj Upadhyay (1): rcu-tasks: Report stalls during synchronize_srcu() in rcu_tasks_postscan() Paul E. McKenney (35): rcutorture: Add test_nmis module parameter rcutorture: Set CONFIG_BOOTPARAM_HOTPLUG_CPU0 to offline CPU 0 rcutorture: Make scenario TREE04 enable lazy call_rcu() torture: Permit kvm-again.sh --duration to default to previous run torture: Enable clocksource watchdog with "tsc=watchdog" rcuscale: Move shutdown from wait_event() to wait_event_idle() refscale: Move shutdown from wait_event() to wait_event_idle() rcutorture: Add SRCU deadlock scenarios rcutorture: Add RCU Tasks Trace and SRCU deadlock scenarios rcutorture: Add srcu_lockdep.sh rcu-tasks: Fix warning for unused tasks_rcu_exit_srcu srcu: Add whitespace to __SRCU_STRUCT_INIT() & __DEFINE_SRCU() srcu: Use static init for statically allocated in-module srcu_struct srcu: Begin offloading srcu_struct fields to srcu_update srcu: Move ->level from srcu_struct to srcu_usage srcu: Move ->srcu_size_state from srcu_struct to srcu_usage srcu: Move ->srcu_cb_mutex from srcu_struct to srcu_usage srcu: Move ->lock initialization after srcu_usage allocation srcu: Move ->lock from srcu_struct to srcu_usage srcu: Move ->srcu_gp_mutex from srcu_struct to srcu_usage srcu: Move grace-period fields from srcu_struct to srcu_usage srcu: Move heuristics fields from srcu_struct to srcu_usage srcu: Move ->sda_is_static from srcu_struct to srcu_usage srcu: Move srcu_barrier() fields from srcu_struct to srcu_usage srcu: Move work-scheduling fields from srcu_struct to srcu_usage srcu: Check for readers at module-exit time srcu: Fix long lines in srcu_get_delay() srcu: Fix long lines in cleanup_srcu_struct() srcu: Fix long lines in srcu_gp_end() srcu: Fix long lines in srcu_funnel_gp_start() rcu: Add comment to rcu_do_batch() identifying rcuoc code path rcu: Remove CONFIG_SRCU mm: Remove "select SRCU" kvm: Remove "select SRCU" arch/x86: Remove "select SRCU" Pingfan Liu (1): srcu: Add comments for srcu_size_state Qiuxu Zhuo (1): Documentation/RCU: s/not/note/ in checklist.rst Randy Dunlap (1): Documentation: RCU: Correct spelling Uladzislau Rezki (Sony) (9): doc: Update whatisRCU.rst drbd: Rename kvfree_rcu() to kvfree_rcu_mightsleep() misc: vmw_vmci: Rename kvfree_rcu() to kvfree_rcu_mightsleep() tracing: Rename kvfree_rcu() to kvfree_rcu_mightsleep() lib/test_vmalloc.c: Rename kvfree_rcu() to kvfree_rcu_mightsleep() net/sysctl: Rename kvfree_rcu() to kvfree_rcu_mightsleep() net/mlx5: Rename kfree_rcu() to kfree_rcu_mightsleep() ext4/super: Rename kfree_rcu() to kfree_rcu_mightsleep() rcuscale: Rename kfree_rcu() to kfree_rcu_mightsleep() Xu Panda (1): rcu/trace: use strscpy() to instead of strncpy() Yue Hu (1): rcutorture: Eliminate variable n_rcu_torture_boost_rterror Zheng Yejian (1): rcu: Avoid stack overflow due to __rcu_irq_enter_check_tick() being kprobe-ed Zqiang (7): rcutorture: Create nocb kthreads only when testing rcu in CONFIG_RCU_NOCB_CPU=y kernels rcu: Fix set/clear TICK_DEP_BIT_RCU_EXP bitmask race rcu: Fix missing TICK_DEP_MASK_RCU_EXP dependency check rcu: Register rcu-lazy shrinker only for CONFIG_RCU_LAZY=y kernels rcu: Remove never-set needwake assignment from rcu_report_qs_rdp() rcu: Permit start_poll_synchronize_rcu_expedited() to be invoked early rcu: Protect rcu_print_task_exp_stall() ->exp_tasks access .../Expedited-Grace-Periods.rst | 6 +- .../Memory-Ordering/Tree-RCU-Memory-Ordering.rst | 2 +- Documentation/RCU/RTFP.txt | 10 +- Documentation/RCU/UP.rst | 4 +- Documentation/RCU/checklist.rst | 2 +- Documentation/RCU/lockdep.rst | 2 +- Documentation/RCU/torture.rst | 4 +- Documentation/RCU/whatisRCU.rst | 6 +- MAINTAINERS | 4 +- arch/arm64/kvm/Kconfig | 1 - arch/mips/kvm/Kconfig | 1 - arch/powerpc/kvm/Kconfig | 1 - arch/riscv/kvm/Kconfig | 1 - arch/s390/kvm/Kconfig | 1 - arch/x86/Kconfig | 2 - arch/x86/kvm/Kconfig | 1 - drivers/base/cpu.c | 3 +- drivers/block/drbd/drbd_nl.c | 6 +- drivers/block/drbd/drbd_receiver.c | 4 +- drivers/block/drbd/drbd_state.c | 2 +- drivers/misc/vmw_vmci/vmci_context.c | 2 +- drivers/misc/vmw_vmci/vmci_event.c | 2 +- .../ethernet/mellanox/mlx5/core/en/tc/int_port.c | 2 +- .../ethernet/mellanox/mlx5/core/en_accel/macsec.c | 4 +- fs/ext4/super.c | 2 +- include/linux/lockdep.h | 8 +- include/linux/notifier.h | 5 +- include/linux/srcu.h | 34 +- include/linux/srcutiny.h | 6 +- include/linux/srcutree.h | 94 +++-- include/linux/tick.h | 2 + include/trace/events/rcu.h | 4 +- include/trace/events/timer.h | 3 +- kernel/locking/lockdep.c | 64 ++- kernel/locking/test-ww_mutex.c | 2 +- kernel/rcu/Kconfig | 3 - kernel/rcu/rcu.h | 43 +- kernel/rcu/rcuscale.c | 9 +- kernel/rcu/rcutorture.c | 234 ++++++++++- kernel/rcu/refscale.c | 2 +- kernel/rcu/srcutiny.c | 2 + kernel/rcu/srcutree.c | 438 ++++++++++++--------- kernel/rcu/tasks.h | 33 ++ kernel/rcu/tree.c | 18 +- kernel/rcu/tree_exp.h | 16 +- kernel/rcu/tree_nocb.h | 4 + kernel/time/tick-sched.c | 16 +- kernel/trace/trace_osnoise.c | 2 +- kernel/trace/trace_probe.c | 2 +- lib/test_vmalloc.c | 2 +- mm/Kconfig | 1 - net/core/sysctl_net_core.c | 4 +- net/mac802154/scan.c | 4 +- scripts/checkpatch.pl | 9 + tools/rcu/extract-stall.sh | 26 +- .../testing/selftests/rcutorture/bin/kvm-again.sh | 2 +- .../selftests/rcutorture/bin/srcu_lockdep.sh | 78 ++++ tools/testing/selftests/rcutorture/bin/torture.sh | 6 +- .../selftests/rcutorture/configs/rcu/TREE01 | 1 + .../selftests/rcutorture/configs/rcu/TREE04 | 1 + .../selftests/rcutorture/doc/TREE_RCU-kconfig.txt | 4 - 61 files changed, 915 insertions(+), 342 deletions(-) mode change 100644 => 100755 tools/rcu/extract-stall.sh create mode 100755 tools/testing/selftests/rcutorture/bin/srcu_lockdep.sh
