================================================================== BUG: KCSAN: data-race in rcu_gp_fqs_check_wake / rcu_note_context_switch write to 0xffffffff85c7d190 of 8 bytes by task 8832 on cpu 1: rcu_preempt_ctxt_queue kernel/rcu/tree_plugin.h:223 [inline] rcu_note_context_switch+0x6f6/0x760 kernel/rcu/tree_plugin.h:315 __schedule+0xa4/0x690 kernel/sched/core.c:4019 preempt_schedule_irq+0x57/0x90 kernel/sched/core.c:4338 restore_regs_and_return_to_kernel+0x0/0x25 arch_local_irq_restore arch/x86/include/asm/paravirt.h:752 [inline] kcsan_setup_watchpoint+0x1d4/0x460 kernel/kcsan/core.c:429 check_access kernel/kcsan/core.c:459 [inline] __tsan_read8+0xc6/0x100 kernel/kcsan/core.c:589 arch_local_save_flags arch/x86/include/asm/paravirt.h:747 [inline] arch_local_irq_save arch/x86/include/asm/paravirt.h:769 [inline] count_memcg_events include/linux/memcontrol.h:748 [inline] count_memcg_event_mm include/linux/memcontrol.h:771 [inline] handle_mm_fault+0xbf/0x530 mm/memory.c:4092 do_user_addr_fault arch/x86/mm/fault.c:1441 [inline] __do_page_fault+0x456/0x8d0 arch/x86/mm/fault.c:1506 do_page_fault+0x38/0x194 arch/x86/mm/fault.c:1530 page_fault+0x34/0x40 arch/x86/entry/entry_64.S:1203 copy_user_enhanced_fast_string+0xe/0x30 arch/x86/lib/copy_user_64.S:204 copy_page_to_iter_iovec lib/iov_iter.c:211 [inline] copy_page_to_iter+0x252/0x8d0 lib/iov_iter.c:920 generic_file_buffered_read mm/filemap.c:2144 [inline] generic_file_read_iter+0x978/0x1440 mm/filemap.c:2324 blkdev_read_iter+0xb2/0xe0 fs/block_dev.c:2039 call_read_iter include/linux/fs.h:1896 [inline] do_iter_readv_writev+0x54b/0x5b0 fs/read_write.c:691 do_iter_read+0x1fc/0x3d0 fs/read_write.c:933 vfs_readv+0x9c/0xf0 fs/read_write.c:997 do_preadv+0x131/0x1d0 fs/read_write.c:1089 __do_sys_preadv fs/read_write.c:1139 [inline] __se_sys_preadv fs/read_write.c:1134 [inline] __x64_sys_preadv+0x61/0x80 fs/read_write.c:1134 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffffffff85c7d190 of 8 bytes by task 10 on cpu 0: rcu_gp_fqs_check_wake kernel/rcu/tree.c:1606 [inline] rcu_gp_fqs_check_wake+0x93/0xd0 kernel/rcu/tree.c:1596 rcu_gp_fqs_loop+0x1df/0x580 kernel/rcu/tree.c:1661 rcu_gp_kthread+0x143/0x230 kernel/rcu/tree.c:1821 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 10 Comm: rcu_preempt Not tainted 5.5.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================