================================================================== 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+0x13d/0x250 kernel/time/timer.c:1463 __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 __sanitizer_cov_trace_cmp4+0x4/0xa0 kernel/kcov.c:258 get_max_io_size block/blk-merge.c:155 [inline] blk_bio_segment_split block/blk-merge.c:253 [inline] __blk_queue_split+0x551/0xc50 block/blk-merge.c:339 blk_mq_submit_bio+0xd3/0xe80 block/blk-mq.c:2190 __submit_bio_noacct_mq block/blk-core.c:1011 [inline] submit_bio_noacct+0x6f2/0x7e0 block/blk-core.c:1044 submit_bio+0x10c/0x190 include/linux/vmstat.h:81 submit_bio_wait+0x86/0xc0 block/bio.c:1155 blkdev_issue_flush+0x6c/0x90 block/blk-flush.c:445 fat_file_fsync+0xe7/0x100 fs/fat/file.c:198 vfs_fsync_range+0x107/0x120 fs/sync.c:200 generic_write_sync include/linux/fs.h:2987 [inline] generic_file_write_iter+0x103/0x130 mm/filemap.c:3819 call_write_iter include/linux/fs.h:2114 [inline] do_iter_readv_writev+0x2cb/0x360 fs/read_write.c:740 do_iter_write+0x112/0x4c0 fs/read_write.c:866 vfs_iter_write+0x4c/0x70 fs/read_write.c:907 iter_file_splice_write+0x40a/0x750 fs/splice.c:689 do_splice_from fs/splice.c:767 [inline] direct_splice_actor+0x80/0xa0 fs/splice.c:936 splice_direct_to_actor+0x345/0x650 fs/splice.c:891 do_splice_direct+0xf5/0x170 fs/splice.c:979 do_sendfile+0x773/0xda0 fs/read_write.c:1260 __do_sys_sendfile64 fs/read_write.c:1325 [inline] __se_sys_sendfile64 fs/read_write.c:1311 [inline] __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1311 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 480 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 freezable_schedule_timeout include/linux/freezer.h:192 [inline] kcompactd+0x349/0xc00 mm/compaction.c:2904 kthread+0x262/0x280 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 value changed: 0xffffc90000c53d60 -> 0x0000000000000000 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 480 Comm: kcompactd0 Not tainted 5.14.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================