================================================================== BUG: KCSAN: data-race in device_del / mm_update_next_owner write to 0xffff88801edbb02c of 4 bytes by task 8398 on cpu 0: memalloc_noio_restore include/linux/sched/mm.h:228 [inline] device_del+0x8a0/0x8f0 drivers/base/core.c:3435 device_unregister+0x11/0x30 drivers/base/core.c:3454 bdi_unregister+0x2b9/0x350 mm/backing-dev.c:876 release_bdi mm/backing-dev.c:892 [inline] kref_put include/linux/kref.h:65 [inline] bdi_put+0x8d/0x190 mm/backing-dev.c:900 generic_shutdown_super+0x1c4/0x210 fs/super.c:478 kill_anon_super+0x23/0x40 fs/super.c:1056 fuse_kill_sb_anon+0xfa/0x110 fs/fuse/inode.c:1574 deactivate_locked_super+0x6a/0xb0 fs/super.c:335 deactivate_super+0x85/0x90 fs/super.c:366 cleanup_mnt+0x277/0x2e0 fs/namespace.c:1136 __cleanup_mnt+0x15/0x20 fs/namespace.c:1143 task_work_run+0x8e/0x110 kernel/task_work.c:140 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:174 [inline] exit_to_user_mode_prepare+0x17c/0x1b0 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:301 do_syscall_64+0x45/0x80 arch/x86/entry/common.c:56 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff88801edbb02c of 4 bytes by task 24593 on cpu 1: mm_update_next_owner+0x1d9/0x4b0 kernel/exit.c:388 exit_mm+0x33c/0x430 kernel/exit.c:500 do_exit+0x3fc/0x15e0 kernel/exit.c:812 do_group_exit+0x17d/0x180 kernel/exit.c:922 __do_sys_exit_group+0xb/0x10 kernel/exit.c:933 __se_sys_exit_group+0x5/0x10 kernel/exit.c:931 __x64_sys_exit_group+0x16/0x20 kernel/exit.c:931 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 24593 Comm: syz-executor.5 Not tainted 5.12.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================