================================================================== BUG: KCSAN: data-race in snd_rawmidi_transmit / snd_rawmidi_write write to 0xffff888121d0b878 of 8 bytes by task 3543 on cpu 0: __snd_rawmidi_transmit_ack sound/core/rawmidi.c:1255 [inline] snd_rawmidi_transmit+0x2e6/0x410 sound/core/rawmidi.c:1314 snd_vmidi_output_work+0xf1/0x200 sound/core/seq/seq_virmidi.c:144 process_one_work+0x3e1/0x950 kernel/workqueue.c:2269 worker_thread+0x665/0xbe0 kernel/workqueue.c:2415 kthread+0x20d/0x230 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 read to 0xffff888121d0b878 of 8 bytes by task 15604 on cpu 1: snd_rawmidi_write+0x597/0x6b0 sound/core/rawmidi.c:1475 vfs_write+0x1d7/0x6d0 fs/read_write.c:584 ksys_write+0xce/0x180 fs/read_write.c:639 __do_sys_write fs/read_write.c:651 [inline] __se_sys_write fs/read_write.c:648 [inline] __x64_sys_write+0x3e/0x50 fs/read_write.c:648 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 15604 Comm: syz-executor.3 Not tainted 5.9.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================