==================================================================
BUG: KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt

write to 0xffff888103dd4048 of 8 bytes by interrupt on cpu 0:
 ps2_interrupt+0x50d/0x550 drivers/input/serio/libps2.c:-1
 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_kcov_mode kernel/kcov.c:183 [inline]
 __sanitizer_cov_trace_pc+0x30/0x70 kernel/kcov.c:217
 cnum64_intersect_with+0x20/0x1d0 kernel/bpf/cnum_defs.h:168
 __update_reg64_bounds kernel/bpf/verifier.c:2006 [inline]
 __update_reg_bounds+0x14f/0x430 kernel/bpf/verifier.c:2039
 reg_bounds_sync+0x78/0x270 kernel/bpf/verifier.c:2079
 adjust_scalar_min_max_vals+0x1393/0x1b30 kernel/bpf/verifier.c:14742
 adjust_reg_min_max_vals+0x5b1/0x8f0 kernel/bpf/verifier.c:14858
 check_alu_op kernel/bpf/verifier.c:15098 [inline]
 do_check_insn+0x3e90/0xf4c0 kernel/bpf/verifier.c:17243
 do_check kernel/bpf/verifier.c:17466 [inline]
 do_check_common+0x267c/0x2d30 kernel/bpf/verifier.c:18497
 do_check_main+0x3c/0xd0 kernel/bpf/verifier.c:18585
 bpf_check+0x2e97/0x3250 kernel/bpf/verifier.c:19927
 bpf_prog_load+0xfaf/0x1100 kernel/bpf/syscall.c:3197
 __sys_bpf+0xbae/0xc30 kernel/bpf/syscall.c:6418
 __do_sys_bpf kernel/bpf/syscall.c:6537 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:6534 [inline]
 __x64_sys_bpf+0x69/0x80 kernel/bpf/syscall.c:6534
 x64_sys_call+0x10cb/0x3020 arch/x86/include/generated/asm/syscalls_64.h:322
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888103dd4048 of 8 bytes by task 5337 on cpu 1:
 ps2_do_sendbyte+0x17e/0x320 drivers/input/serio/libps2.c:65
 __ps2_command+0x3b7/0xaa0 drivers/input/serio/libps2.c:328
 ps2_command+0x52/0x90 drivers/input/serio/libps2.c:403
 psmouse_set_resolution+0x7d/0xd0 drivers/input/mouse/psmouse-base.c:448
 psmouse_initialize drivers/input/mouse/psmouse-base.c:1263 [inline]
 psmouse_attr_set_protocol+0x55f/0xb10 drivers/input/mouse/psmouse-base.c:1922
 psmouse_attr_set_helper+0x2aa/0x470 drivers/input/mouse/psmouse-base.c:1813
 dev_attr_store+0x4a/0x70 drivers/base/core.c:2505
 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+0x57d/0x990 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+0x27e1/0x3020 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000001 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 5337 Comm: syz.0.502 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
==================================================================
input: PS/2 Generic Explorer Mouse as /devices/platform/i8042/serio1/input/input8