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BUG: KCSAN: data-race in serial8250_do_startup / serial8250_handle_irq

write to 0xffffffff88ec1e66 of 1 bytes by task 10599 on cpu 1:
 serial8250_do_startup+0x1491/0x1c10 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+0x468/0x8e0 drivers/tty/serial/serial_core.c:365
 uart_port_activate+0x67/0xc0 drivers/tty/serial/serial_core.c:1974
 tty_port_open+0x196/0x270 drivers/tty/tty_port.c:747
 uart_open+0x30/0x40 drivers/tty/serial/serial_core.c:1954
 tty_open+0x3d4/0xaf0 drivers/tty/tty_io.c:2137
 chrdev_open+0x2eb/0x3a0 fs/char_dev.c:414
 do_dentry_open+0x649/0xa20 fs/open.c:965
 vfs_open+0x37/0x1e0 fs/open.c:1097
 do_open fs/namei.c:3975 [inline]
 path_openat+0x1c5e/0x2170 fs/namei.c:4134
 do_filp_open+0x109/0x230 fs/namei.c:4161
 do_sys_openat2+0xa6/0x110 fs/open.c:1437
 do_sys_open fs/open.c:1452 [inline]
 __do_sys_openat fs/open.c:1468 [inline]
 __se_sys_openat fs/open.c:1463 [inline]
 __x64_sys_openat+0xf2/0x120 fs/open.c:1463
 x64_sys_call+0x2eab/0x3000 arch/x86/include/generated/asm/syscalls_64.h:258
 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 0xffffffff88ec1e66 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:82
 __handle_irq_event_percpu+0x9d/0x540 kernel/irq/handle.c:203
 handle_irq_event_percpu kernel/irq/handle.c:240 [inline]
 handle_irq_event+0x64/0xf0 kernel/irq/handle.c:257
 handle_edge_irq+0x154/0x470 kernel/irq/chip.c:855
 generic_handle_irq_desc include/linux/irqdesc.h:173 [inline]
 handle_irq arch/x86/kernel/irq.c:254 [inline]
 call_irq_handler arch/x86/kernel/irq.c:-1 [inline]
 __common_interrupt+0x60/0xb0 arch/x86/kernel/irq.c:325
 common_interrupt+0x7e/0x90 arch/x86/kernel/irq.c:318
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:688
 __preempt_count_dec_and_test arch/x86/include/asm/preempt.h:95 [inline]
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0x3c/0x60 kernel/locking/spinlock.c:194
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 __wake_up_common_lock kernel/sched/wait.c:127 [inline]
 __wake_up+0x88/0xb0 kernel/sched/wait.c:146
 audit_log_end+0x1e0/0x250 kernel/audit.c:2645
 common_lsm_audit+0x1ca/0x230 security/lsm_audit.c:456
 slow_avc_audit+0x104/0x140 security/selinux/avc.c:778
 avc_audit security/selinux/include/avc.h:131 [inline]
 avc_has_perm+0x13a/0x180 security/selinux/avc.c:1197
 sock_has_perm security/selinux/hooks.c:4793 [inline]
 selinux_socket_recvmsg+0x175/0x1b0 security/selinux/hooks.c:5140
 security_socket_recvmsg+0x50/0x90 security/security.c:4774
 sock_recvmsg+0x38/0x170 net/socket.c:1098
 ____sys_recvmsg+0xf5/0x280 net/socket.c:2850
 ___sys_recvmsg+0x11f/0x370 net/socket.c:2892
 __sys_recvmsg net/socket.c:2925 [inline]
 __do_sys_recvmsg net/socket.c:2931 [inline]
 __se_sys_recvmsg net/socket.c:2928 [inline]
 __x64_sys_recvmsg+0xd1/0x160 net/socket.c:2928
 x64_sys_call+0x2b46/0x3000 arch/x86/include/generated/asm/syscalls_64.h:48
 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

value changed: 0x00 -> 0x05

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3044 Comm: dhcpcd Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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