================================================================== BUG: KCSAN: data-race in _prb_read_valid / data_alloc write to 0xffffffff868864f0 of 8 bytes by task 8800 on cpu 1: data_alloc+0x271/0x2b0 kernel/printk/printk_ringbuffer.c:1095 prb_reserve+0x808/0xaf0 kernel/printk/printk_ringbuffer.c:1669 vprintk_store+0x56d/0x860 kernel/printk/printk.c:2326 vprintk_emit+0x178/0x650 kernel/printk/printk.c:2426 vprintk_default+0x26/0x30 kernel/printk/printk.c:2465 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82 _printk+0x79/0xa0 kernel/printk/printk.c:2475 siw_device_register drivers/infiniband/sw/siw/siw_main.c:73 [inline] siw_newlink+0x665/0x680 drivers/infiniband/sw/siw/siw_main.c:430 nldev_newlink+0x369/0x3f0 drivers/infiniband/core/nldev.c:1796 rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:195 [inline] rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline] rdma_nl_rcv+0x47c/0x5a0 drivers/infiniband/core/netlink.c:259 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x5a1/0x670 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x58b/0x6b0 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x145/0x180 net/socket.c:727 ____sys_sendmsg+0x31e/0x4e0 net/socket.c:2566 ___sys_sendmsg+0x17b/0x1d0 net/socket.c:2620 __sys_sendmsg net/socket.c:2652 [inline] __do_sys_sendmsg net/socket.c:2657 [inline] __se_sys_sendmsg net/socket.c:2655 [inline] __x64_sys_sendmsg+0xd4/0x160 net/socket.c:2655 x64_sys_call+0x2999/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffffffff868864f0 of 16 bytes by task 8776 on cpu 0: desc_read kernel/printk/printk_ringbuffer.c:482 [inline] desc_read_finalized_seq kernel/printk/printk_ringbuffer.c:1874 [inline] prb_read kernel/printk/printk_ringbuffer.c:1922 [inline] _prb_read_valid+0x1bc/0x920 kernel/printk/printk_ringbuffer.c:2113 prb_read_valid+0x3c/0x60 kernel/printk/printk_ringbuffer.c:2185 __console_flush_and_unlock kernel/printk/printk.c:3304 [inline] console_unlock+0x164/0x330 kernel/printk/printk.c:3325 con_flush_chars+0xb2/0x1b0 drivers/tty/vt/vt.c:3587 n_tty_write+0x8e3/0xb10 drivers/tty/n_tty.c:2393 iterate_tty_write drivers/tty/tty_io.c:1006 [inline] file_tty_write+0x38c/0x670 drivers/tty/tty_io.c:1081 tty_write+0x25/0x30 drivers/tty/tty_io.c:1102 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x4a0/0x8e0 fs/read_write.c:686 ksys_write+0xda/0x1a0 fs/read_write.c:738 __do_sys_write fs/read_write.c:749 [inline] __se_sys_write fs/read_write.c:746 [inline] __x64_sys_write+0x40/0x50 fs/read_write.c:746 x64_sys_call+0x2cdd/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:2 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Reported by Kernel Concurrency Sanitizer on: CPU: 0 UID: 0 PID: 8776 Comm: syz.8.24853 Tainted: G W 6.16.0-rc2-syzkaller-00087-g24770983ccfe #0 PREEMPT(voluntary) Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 ==================================================================