devtmpfs: Unknown parameter 'devtmpfs'
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BUG: KCSAN: data-race in data_alloc / data_push_tail

write to 0xffffffff86f3fea8 of 8 bytes by task 31707 on cpu 1:
 data_alloc+0x216/0x2c0 kernel/printk/printk_ringbuffer.c:1074
 prb_reserve+0x893/0xbc0 kernel/printk/printk_ringbuffer.c:1555
 vprintk_store+0x53e/0x800 kernel/printk/printk.c:2232
 vprintk_emit+0xd0/0x430 kernel/printk/printk.c:2288
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2318
 vprintk+0x83/0x90 kernel/printk/printk_safe.c:50
 _printk+0x7a/0xa0 kernel/printk/printk.c:2328
 chnl_flowctrl_cb+0x206/0x480 net/caif/chnl_net.c:151
 caif_disconnect_client+0xe3/0x140 net/caif/cfcnfg.c:199
 chnl_net_open+0x50b/0x5b0 net/caif/chnl_net.c:326
 __dev_open+0x281/0x3a0 net/core/dev.c:1442
 __dev_change_flags+0x159/0x400 net/core/dev.c:8530
 dev_change_flags+0x59/0xd0 net/core/dev.c:8602
 do_setlink+0x9f6/0x2430 net/core/rtnetlink.c:2867
 rtnl_group_changelink net/core/rtnetlink.c:3409 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3665 [inline]
 rtnl_newlink+0xb98/0x1600 net/core/rtnetlink.c:3702
 rtnetlink_rcv_msg+0x807/0x8c0 net/core/rtnetlink.c:6424
 netlink_rcv_skb+0x126/0x220 net/netlink/af_netlink.c:2549
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:6442
 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline]
 netlink_unicast+0x56f/0x640 net/netlink/af_netlink.c:1365
 netlink_sendmsg+0x665/0x770 net/netlink/af_netlink.c:1914
 sock_sendmsg_nosec net/socket.c:725 [inline]
 sock_sendmsg net/socket.c:748 [inline]
 ____sys_sendmsg+0x37c/0x4d0 net/socket.c:2494
 ___sys_sendmsg net/socket.c:2548 [inline]
 __sys_sendmsg+0x1e9/0x270 net/socket.c:2577
 __do_sys_sendmsg net/socket.c:2586 [inline]
 __se_sys_sendmsg net/socket.c:2584 [inline]
 __x64_sys_sendmsg+0x46/0x50 net/socket.c:2584
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffffffff86f3fea8 of 8 bytes by task 31717 on cpu 0:
 data_make_reusable kernel/printk/printk_ringbuffer.c:590 [inline]
 data_push_tail+0x102/0x430 kernel/printk/printk_ringbuffer.c:675
 data_alloc+0xbe/0x2c0 kernel/printk/printk_ringbuffer.c:1046
 prb_reserve+0x893/0xbc0 kernel/printk/printk_ringbuffer.c:1555
 vprintk_store+0x53e/0x800 kernel/printk/printk.c:2232
 vprintk_emit+0xd0/0x430 kernel/printk/printk.c:2288
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2318
 vprintk+0x83/0x90 kernel/printk/printk_safe.c:50
 _printk+0x7a/0xa0 kernel/printk/printk.c:2328
 logfc+0x2cd/0x2e0
 vfs_parse_fs_param+0x1cf/0x290 fs/fs_context.c:158
 vfs_parse_fs_string+0x90/0xd0 fs/fs_context.c:184
 shmem_parse_options+0x112/0x160 mm/shmem.c:3768
 parse_monolithic_mount_data+0x42/0x50 fs/fs_context.c:668
 reconfigure_single+0x4d/0x90 fs/super.c:1460
 public_dev_mount+0x4f/0xb0 drivers/base/devtmpfs.c:74
 legacy_get_tree+0x74/0xd0 fs/fs_context.c:611
 vfs_get_tree+0x51/0x190 fs/super.c:1519
 vfs_fsconfig_locked fs/fsopen.c:232 [inline]
 __do_sys_fsconfig fs/fsopen.c:439 [inline]
 __se_sys_fsconfig+0x7b5/0xa00 fs/fsopen.c:314
 __x64_sys_fsconfig+0x67/0x80 fs/fsopen.c:314
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000000100000a84 -> 0x00000001000015aa

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 31717 Comm: syz-executor.2 Not tainted 6.5.0-rc3-syzkaller-00297-gd31e3792919e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023
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