================================================================== BUG: KCSAN: data-race in do_syslog / log_store write to 0xffffffff89513200 of 8 bytes by task 29877 on cpu 1: log_store+0x7a2/0x7d0 kernel/printk/printk.c:672 log_output kernel/printk/printk.c:1932 [inline] vprintk_store+0x5ba/0x700 kernel/printk/printk.c:1983 vprintk_emit+0x114/0x4f0 kernel/printk/printk.c:2011 vprintk_default+0x24/0x30 kernel/printk/printk.c:2047 vprintk_func+0x13d/0x140 kernel/printk/printk_safe.c:393 printk+0x62/0x82 kernel/printk/printk.c:2078 __dev_set_promiscuity+0x18c/0x390 net/core/dev.c:8076 __dev_set_rx_mode+0x13c/0x180 net/core/dev.c:8200 dev_uc_del+0x1ee/0x210 net/core/dev_addr_lists.c:614 macvlan_stop+0x1ab/0x260 drivers/net/macvlan.c:693 __dev_close_many+0x1f6/0x2c0 net/core/dev.c:1605 dev_close_many+0x114/0x310 net/core/dev.c:1630 rollback_registered_many+0x262/0xd20 net/core/dev.c:9261 unregister_netdevice_many net/core/dev.c:10429 [inline] default_device_exit_batch+0x250/0x3e0 net/core/dev.c:10912 ops_exit_list net/core/net_namespace.c:189 [inline] cleanup_net+0x4dc/0x8c0 net/core/net_namespace.c:603 process_one_work+0x3e1/0x9a0 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:294 read to 0xffffffff89513200 of 8 bytes by task 8335 on cpu 0: do_syslog+0x2e4/0x1480 kernel/printk/printk.c:1561 kmsg_read+0x7a/0xa0 fs/proc/kmsg.c:40 pde_read fs/proc/inode.c:306 [inline] proc_reg_read+0xde/0x1a0 fs/proc/inode.c:316 vfs_read+0x16d/0x5e0 fs/read_write.c:479 ksys_read+0xce/0x180 fs/read_write.c:607 __do_sys_read fs/read_write.c:617 [inline] __se_sys_read fs/read_write.c:615 [inline] __x64_sys_read+0x3e/0x50 fs/read_write.c:615 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: 0 PID: 8335 Comm: in:imklog Not tainted 5.9.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================