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BUG: KCSAN: data-race in serial8250_do_startup / serial8250_handle_irq

write to 0xffffffff8917bdf6 of 1 bytes by task 6536 on cpu 1:
 serial8250_do_startup+0x169b/0x1dd0 drivers/tty/serial/8250/8250_port.c:2327
 serial8250_startup+0x41/0x50 drivers/tty/serial/8250/8250_port.c:2347
 uart_port_startup drivers/tty/serial/serial_core.c:321 [inline]
 uart_startup+0x464/0xae0 drivers/tty/serial/serial_core.c:365
 uart_port_activate+0x67/0xc0 drivers/tty/serial/serial_core.c:1946
 tty_port_open+0x196/0x270 drivers/tty/tty_port.c:747
 uart_open+0x30/0x40 drivers/tty/serial/serial_core.c:1926
 tty_open+0x3d4/0xaf0 drivers/tty/tty_io.c:2137
 chrdev_open+0x2eb/0x3a0 fs/char_dev.c:414
 do_dentry_open+0x54b/0xa60 fs/open.c:962
 vfs_open+0x37/0x1e0 fs/open.c:1094
 do_open fs/namei.c:4637 [inline]
 path_openat+0x1de9/0x23c0 fs/namei.c:4796
 do_filp_open+0x15d/0x280 fs/namei.c:4823
 do_sys_openat2+0xa6/0x150 fs/open.c:1430
 do_sys_open fs/open.c:1436 [inline]
 __do_sys_openat fs/open.c:1452 [inline]
 __se_sys_openat fs/open.c:1447 [inline]
 __x64_sys_openat+0xf2/0x120 fs/open.c:1447
 x64_sys_call+0x2b07/0x3000 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc0/0x2a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff8917bdf6 of 1 bytes by interrupt on cpu 0:
 serial8250_handle_irq+0x3f9/0x660 drivers/tty/serial/8250/8250_port.c:1825
 serial8250_default_handle_irq+0x8e/0x170 drivers/tty/serial/8250/8250_port.c:1846
 serial8250_interrupt+0x63/0x130 drivers/tty/serial/8250/8250_core.c:86
 __handle_irq_event_percpu+0x8b/0x4c0 kernel/irq/handle.c:211
 handle_irq_event_percpu kernel/irq/handle.c:248 [inline]
 handle_irq_event+0x64/0xf0 kernel/irq/handle.c:265
 handle_edge_irq+0x154/0x470 kernel/irq/chip.c:855
 generic_handle_irq_desc include/linux/irqdesc.h:172 [inline]
 handle_irq arch/x86/kernel/irq.c:255 [inline]
 call_irq_handler arch/x86/kernel/irq.c:-1 [inline]
 __common_interrupt+0x60/0xb0 arch/x86/kernel/irq.c:326
 common_interrupt+0x7e/0x90 arch/x86/kernel/irq.c:319
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:688
 crng_make_state+0xc1/0x200 drivers/char/random.c:394
 _get_random_bytes+0x85/0x1b0 drivers/char/random.c:406
 get_random_bytes+0x1d/0x30 drivers/char/random.c:438
 eth_random_addr include/linux/etherdevice.h:238 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:826 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:875 [inline]
 nsim_dev_trap_report_work+0x23c/0x630 drivers/net/netdevsim/dev.c:921
 process_one_work kernel/workqueue.c:3257 [inline]
 process_scheduled_works+0x4cd/0x9d0 kernel/workqueue.c:3340
 worker_thread+0x6bc/0x8b0 kernel/workqueue.c:3421
 kthread+0x488/0x510 kernel/kthread.c:463
 ret_from_fork+0x148/0x280 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

value changed: 0x00 -> 0x05

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 11095 Comm: kworker/u8:31 Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events_unbound nsim_dev_trap_report_work
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