================================================================== BUG: KCSAN: data-race in expire_timers / try_to_del_timer_sync write to 0xffff888237d376c8 of 8 bytes by interrupt on cpu 1: expire_timers+0x17f/0x250 kernel/time/timer.c:1458 __run_timers+0x358/0x420 kernel/time/timer.c:1731 run_timer_softirq+0x19/0x30 kernel/time/timer.c:1744 __do_softirq+0x12c/0x26e kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x9a/0xb0 kernel/softirq.c:636 sysvec_apic_timer_interrupt+0x69/0x80 arch/x86/kernel/apic/apic.c:1100 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 isolate_lru_page+0x30b/0x370 mm/vmscan.c:1983 mlock_vma_page+0x135/0x190 mm/mlock.c:104 follow_page_pte mm/gup.c:611 [inline] follow_pmd_mask mm/gup.c:682 [inline] follow_pud_mask mm/gup.c:765 [inline] follow_p4d_mask mm/gup.c:791 [inline] follow_page_mask+0xdd3/0x1040 mm/gup.c:850 __get_user_pages+0x2e6/0xbc0 mm/gup.c:1171 populate_vma_page_range mm/gup.c:1506 [inline] __mm_populate+0x24d/0x380 mm/gup.c:1612 mm_populate include/linux/mm.h:2623 [inline] __do_sys_mlockall+0x246/0x2c0 mm/mlock.c:799 __se_sys_mlockall mm/mlock.c:775 [inline] __x64_sys_mlockall+0x1a/0x20 mm/mlock.c:775 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff888237d376c8 of 8 bytes by task 11 on cpu 0: try_to_del_timer_sync+0xe3/0x290 kernel/time/timer.c:1231 del_timer_sync kernel/time/timer.c:1378 [inline] schedule_timeout+0x108/0x240 kernel/time/timer.c:1879 rcu_gp_fqs_loop kernel/rcu/tree.c:1996 [inline] rcu_gp_kthread+0xbf7/0xec0 kernel/rcu/tree.c:2169 kthread+0x262/0x280 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 value changed: 0xffffffff8375f600 -> 0x0000000000000000 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 11 Comm: rcu_sched Tainted: G W 5.14.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================