==================================================================
BUG: KCSAN: data-race in __ps2_command / ps2_interrupt

write to 0xffff888103de7248 of 8 bytes by interrupt on cpu 0:
 ps2_handle_response drivers/input/serio/libps2.c:482 [inline]
 ps2_interrupt+0x273/0x550 drivers/input/serio/libps2.c:608
 serio_interrupt+0x66/0xf0 drivers/input/serio/serio.c:967
 i8042_handle_data+0x388/0x680 drivers/input/serio/i8042.c:598
 i8042_interrupt+0x15/0x90 drivers/input/serio/i8042.c:605
 __handle_irq_event_percpu+0x8b/0x480 kernel/irq/handle.c:209
 handle_irq_event_percpu kernel/irq/handle.c:246 [inline]
 handle_irq_event+0x64/0xf0 kernel/irq/handle.c:263
 handle_edge_irq+0x155/0x440 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+0x60/0xb0 arch/x86/kernel/irq.c:280
 common_interrupt+0x7e/0x90 arch/x86/kernel/irq.c:273
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:665
 check_access kernel/kcsan/core.c:795 [inline]
 __tsan_read2+0x122/0x190 kernel/kcsan/core.c:1031
 mpol_needs_cond_ref include/linux/mempolicy.h:79 [inline]
 mpol_cond_put include/linux/mempolicy.h:84 [inline]
 vma_alloc_folio_noprof+0x1ed/0x300 mm/mempolicy.c:2541
 folio_prealloc mm/memory.c:-1 [inline]
 wp_page_copy mm/memory.c:4007 [inline]
 do_wp_page+0x64d/0x1ed0 mm/memory.c:4472
 handle_pte_fault mm/memory.c:6582 [inline]
 __handle_mm_fault mm/memory.c:6707 [inline]
 handle_mm_fault+0xe29/0x3bb0 mm/memory.c:6876
 do_user_addr_fault+0x404/0x1060 arch/x86/mm/fault.c:1394
 handle_page_fault arch/x86/mm/fault.c:1483 [inline]
 exc_page_fault+0x62/0xa0 arch/x86/mm/fault.c:1536
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595
 __put_user_nocheck_4+0x3/0x20 arch/x86/lib/putuser.S:97
 ____sys_recvmsg+0x1a1/0x280 net/socket.c:2946
 ___sys_recvmsg+0x11f/0x3a0 net/socket.c:2975
 do_recvmmsg+0x1e5/0x560 net/socket.c:3070
 __sys_recvmmsg net/socket.c:3144 [inline]
 __do_sys_recvmmsg net/socket.c:3167 [inline]
 __se_sys_recvmmsg net/socket.c:3160 [inline]
 __x64_sys_recvmmsg+0xe5/0x170 net/socket.c:3160
 x64_sys_call+0x77f/0x2550 arch/x86/include/generated/asm/syscalls_64.h:300
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888103de7248 of 8 bytes by task 11848 on cpu 1:
 __ps2_command+0x439/0xaa0 drivers/input/serio/libps2.c:341
 ps2_command+0x52/0x90 drivers/input/serio/libps2.c:403
 genius_detect+0x8b/0x250 drivers/input/mouse/psmouse-base.c:549
 psmouse_do_detect drivers/input/mouse/psmouse-base.c:995 [inline]
 psmouse_try_protocol drivers/input/mouse/psmouse-base.c:1009 [inline]
 psmouse_extensions+0x7af/0x960 drivers/input/mouse/psmouse-base.c:1158
 __psmouse_reconnect+0x3dd/0x880 drivers/input/mouse/psmouse-base.c:1685
 psmouse_reconnect+0x23/0x40 drivers/input/mouse/psmouse-base.c:1723
 serio_reconnect_driver drivers/input/serio/serio.c:52 [inline]
 serio_reconnect_port drivers/input/serio/serio.c:558 [inline]
 serio_reconnect_subtree drivers/input/serio/serio.c:578 [inline]
 drvctl_store+0x2ac/0xc20 drivers/input/serio/serio.c:364
 dev_attr_store+0x4a/0x70 drivers/base/core.c:2509
 sysfs_kf_write+0xfe/0x120 fs/sysfs/file.c:145
 kernfs_fop_write_iter+0x1d2/0x2e0 fs/kernfs/file.c:345
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x57f/0x9a0 fs/read_write.c:687
 ksys_write+0xdc/0x1a0 fs/read_write.c:739
 __do_sys_write fs/read_write.c:750 [inline]
 __se_sys_write fs/read_write.c:747 [inline]
 __x64_sys_write+0x40/0x50 fs/read_write.c:747
 x64_sys_call+0x154e/0x2550 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000006 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 11848 Comm: syz.5.2410 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
==================================================================