================================================================== BUG: KCSAN: data-race in __perf_event_overflow / fasync_remove_entry write to 0xffff88809b5f8ef8 of 8 bytes by task 13712 on cpu 0: fasync_remove_entry+0xba/0x120 fs/fcntl.c:882 fasync_helper+0xcf/0xdc fs/fcntl.c:981 perf_fasync+0x6c/0xa0 kernel/events/core.c:5917 __fput+0x46a/0x520 fs/file_table.c:277 ____fput+0x1f/0x30 fs/file_table.c:313 task_work_run+0xf6/0x130 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x2b4/0x2c0 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline] syscall_return_slowpath arch/x86/entry/common.c:274 [inline] do_syscall_64+0x353/0x370 arch/x86/entry/common.c:300 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffff88809b5f8ef8 of 8 bytes by interrupt on cpu 1: __perf_event_overflow+0x11d/0x200 kernel/events/core.c:8192 perf_swevent_hrtimer+0x261/0x280 kernel/events/core.c:9576 __run_hrtimer kernel/time/hrtimer.c:1514 [inline] __hrtimer_run_queues+0x274/0x5f0 kernel/time/hrtimer.c:1576 hrtimer_interrupt+0x22a/0x480 kernel/time/hrtimer.c:1638 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline] smp_apic_timer_interrupt+0xdc/0x280 arch/x86/kernel/apic/apic.c:1135 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830 preempt_count arch/x86/include/asm/preempt.h:26 [inline] get_ctx kernel/kcsan/core.c:175 [inline] is_atomic kernel/kcsan/core.c:180 [inline] should_watch kernel/kcsan/core.c:211 [inline] check_access kernel/kcsan/core.c:465 [inline] __tsan_unaligned_write8+0x6c/0x100 kernel/kcsan/core.c:596 INIT_LIST_HEAD include/linux/list.h:29 [inline] list_del_init include/linux/list.h:191 [inline] blk_mq_flush_plug_list+0x29f/0x6c0 block/blk-mq.c:1746 blk_flush_plug_list+0x271/0x2a0 block/blk-core.c:1766 blk_mq_make_request+0x65e/0xf60 block/blk-mq.c:2014 generic_make_request block/blk-core.c:1064 [inline] generic_make_request+0x196/0x740 block/blk-core.c:1006 submit_bio+0x96/0x3c0 block/blk-core.c:1190 submit_bh_wbc+0x40f/0x460 fs/buffer.c:3095 __block_write_full_page+0x4e9/0x870 fs/buffer.c:1767 block_write_full_page+0x1c0/0x1e0 fs/buffer.c:2953 fat_writepage+0x2e/0x40 fs/fat/inode.c:198 __mpage_writepage+0x837/0xe70 fs/mpage.c:678 write_cache_pages+0x47a/0xb40 mm/page-writeback.c:2238 mpage_writepages+0xab/0x180 fs/mpage.c:730 fat_writepages+0x2e/0x40 fs/fat/inode.c:204 do_writepages+0x6b/0x170 mm/page-writeback.c:2344 __filemap_fdatawrite_range+0x1c5/0x230 mm/filemap.c:421 file_write_and_wait_range+0xfd/0x160 mm/filemap.c:782 __generic_file_fsync+0x59/0x190 fs/libfs.c:1000 fat_file_fsync+0x58/0x120 fs/fat/file.c:199 vfs_fsync_range+0x82/0x150 fs/sync.c:197 generic_write_sync include/linux/fs.h:2853 [inline] generic_file_write_iter+0x318/0x390 mm/filemap.c:3470 call_write_iter include/linux/fs.h:1895 [inline] aio_write+0x1de/0x2d0 fs/aio.c:1583 __io_submit_one fs/aio.c:1815 [inline] io_submit_one+0x639/0xe70 fs/aio.c:1862 __do_sys_io_submit fs/aio.c:1921 [inline] __se_sys_io_submit fs/aio.c:1891 [inline] __x64_sys_io_submit+0x104/0x2d0 fs/aio.c:1891 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 13724 Comm: syz-executor.4 Not tainted 5.4.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================