=====================================================
BUG: KMSAN: uninit-value in variable_test_bit arch/x86/include/asm/bitops.h:222 [inline]
BUG: KMSAN: uninit-value in arch_test_bit arch/x86/include/asm/bitops.h:233 [inline]
BUG: KMSAN: uninit-value in _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline]
BUG: KMSAN: uninit-value in n_tty_receive_buf_standard+0xce6/0xc270 drivers/tty/n_tty.c:1579
 variable_test_bit arch/x86/include/asm/bitops.h:222 [inline]
 arch_test_bit arch/x86/include/asm/bitops.h:233 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline]
 n_tty_receive_buf_standard+0xce6/0xc270 drivers/tty/n_tty.c:1579
 __receive_buf drivers/tty/n_tty.c:1616 [inline]
 n_tty_receive_buf_common+0x1a48/0x2500 drivers/tty/n_tty.c:1715
 n_tty_receive_buf2+0x4c/0x60 drivers/tty/n_tty.c:1759
 tty_ldisc_receive_buf+0xc6/0x2c0 drivers/tty/tty_buffer.c:394
 tty_port_default_receive_buf+0xd7/0x1a0 drivers/tty/tty_port.c:37
 receive_buf drivers/tty/tty_buffer.c:452 [inline]
 flush_to_ldisc+0x482/0xe60 drivers/tty/tty_buffer.c:502
 process_one_work kernel/workqueue.c:3322 [inline]
 process_scheduled_works+0xb57/0x1e10 kernel/workqueue.c:3405
 worker_thread+0xee0/0x1580 kernel/workqueue.c:3486
 kthread+0x54f/0x610 kernel/kthread.c:436
 ret_from_fork+0x20f/0x8e0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4617 [inline]
 slab_alloc_node mm/slub.c:4939 [inline]
 __do_kmalloc_node mm/slub.c:5333 [inline]
 __kmalloc_noprof+0x47e/0x1610 mm/slub.c:5347
 _kmalloc_noprof include/linux/slab.h:973 [inline]
 tty_buffer_alloc drivers/tty/tty_buffer.c:187 [inline]
 __tty_buffer_request_room+0x3d7/0x7a0 drivers/tty/tty_buffer.c:280
 __tty_insert_flip_string_flags+0x157/0x6e0 drivers/tty/tty_buffer.c:316
 tty_insert_flip_char include/linux/tty_flip.h:77 [inline]
 uart_insert_char+0x2fe/0x920 drivers/tty/serial/serial_core.c:3431
 serial8250_read_char+0x1af/0x670 drivers/tty/serial/8250/8250_port.c:1643
 serial8250_rx_chars drivers/tty/serial/8250/8250_port.c:1660 [inline]
 serial8250_handle_irq_locked+0x6d4/0xa40 drivers/tty/serial/8250/8250_port.c:1823
 serial8250_handle_irq+0x187/0x6f0 drivers/tty/serial/8250/8250_port.c:1844
 serial8250_default_handle_irq+0x112/0x330 drivers/tty/serial/8250/8250_port.c:1858
 serial8250_interrupt+0xcb/0x3e0 drivers/tty/serial/8250/8250_core.c:86
 __handle_irq_event_percpu+0x11e/0xf10 kernel/irq/handle.c:209
 handle_irq_event_percpu kernel/irq/handle.c:246 [inline]
 handle_irq_event+0xe0/0x2a0 kernel/irq/handle.c:263
 handle_edge_irq+0x2aa/0xaf0 kernel/irq/chip.c:859
 generic_handle_irq_desc include/linux/irqdesc.h:188 [inline]
 handle_irq arch/x86/kernel/irq.c:209 [inline]
 call_irq_handler arch/x86/kernel/irq.c:-1 [inline]
 __common_interrupt+0x9d/0x180 arch/x86/kernel/irq.c:280
 common_interrupt+0x94/0xb0 arch/x86/kernel/irq.c:273
 asm_common_interrupt+0x2b/0x40 arch/x86/include/asm/idtentry.h:665

CPU: 1 UID: 0 PID: 14 Comm: kworker/u8:1 Tainted: G             L      syzkaller #0 PREEMPT(lazy) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: ttyS-serial_8250 flush_to_ldisc
=====================================================