================================================================== BUG: KCSAN: data-race in data_alloc / data_push_tail write to 0xffffffff86dc37b0 of 8 bytes by task 28932 on cpu 1: data_alloc+0x205/0x2b0 kernel/printk/printk_ringbuffer.c:1071 prb_reserve+0x920/0xbf0 kernel/printk/printk_ringbuffer.c:1549 vprintk_store+0x560/0xbb0 kernel/printk/printk.c:2176 vprintk_emit+0xac/0x3c0 kernel/printk/printk.c:2229 vprintk_default+0x22/0x30 kernel/printk/printk.c:2256 vprintk+0x7f/0x90 kernel/printk/printk_safe.c:50 _printk+0x76/0x97 kernel/printk/printk.c:2266 __ext4_msg+0x117/0x180 fs/ext4/super.c:946 ext4_check_opt_consistency+0x175/0x8c0 fs/ext4/super.c:2796 __ext4_fill_super+0x11c1/0x59b0 fs/ext4/super.c:4605 ext4_fill_super+0xfd/0x2f0 fs/ext4/super.c:5554 get_tree_bdev+0x2c2/0x3d0 fs/super.c:1292 vfs_get_tree+0x4a/0x1a0 fs/super.c:1497 do_new_mount fs/namespace.c:2994 [inline] path_mount+0x11cf/0x1c40 fs/namespace.c:3324 do_mount fs/namespace.c:3337 [inline] __do_sys_mount fs/namespace.c:3545 [inline] __se_sys_mount+0x24b/0x2f0 fs/namespace.c:3522 __x64_sys_mount+0x63/0x70 fs/namespace.c:3522 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffffffff86dc37b0 of 8 bytes by task 28933 on cpu 0: data_make_reusable kernel/printk/printk_ringbuffer.c:587 [inline] data_push_tail+0x138/0x470 kernel/printk/printk_ringbuffer.c:672 data_alloc+0xbc/0x2b0 kernel/printk/printk_ringbuffer.c:1043 prb_reserve+0x920/0xbf0 kernel/printk/printk_ringbuffer.c:1549 vprintk_store+0x560/0xbb0 kernel/printk/printk.c:2176 vprintk_emit+0xac/0x3c0 kernel/printk/printk.c:2229 vprintk_default+0x22/0x30 kernel/printk/printk.c:2256 vprintk+0x7f/0x90 kernel/printk/printk_safe.c:50 _printk+0x76/0x97 kernel/printk/printk.c:2266 __ext4_msg+0x16d/0x180 fs/ext4/super.c:944 __ext4_fill_super+0xa1a/0x59b0 ext4_fill_super+0xfd/0x2f0 fs/ext4/super.c:5554 get_tree_bdev+0x2c2/0x3d0 fs/super.c:1292 vfs_get_tree+0x4a/0x1a0 fs/super.c:1497 do_new_mount fs/namespace.c:2994 [inline] path_mount+0x11cf/0x1c40 fs/namespace.c:3324 do_mount fs/namespace.c:3337 [inline] __do_sys_mount fs/namespace.c:3545 [inline] __se_sys_mount+0x24b/0x2f0 fs/namespace.c:3522 __x64_sys_mount+0x63/0x70 fs/namespace.c:3522 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae value changed: 0x00000001000082c5 -> 0x0000000100009020 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 28933 Comm: syz-executor.4 Not tainted 5.17.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================