==================================================================
BUG: KCSAN: data-race in rtc_dev_poll / rtc_pie_update_irq

read-write to 0xffff888103e31398 of 8 bytes by interrupt on cpu 1:
 rtc_handle_legacy_irq drivers/rtc/interface.c:651 [inline]
 rtc_pie_update_irq+0x7b/0xd0 drivers/rtc/interface.c:699
 __run_hrtimer kernel/time/hrtimer.c:1785 [inline]
 __hrtimer_run_queues+0x218/0x4f0 kernel/time/hrtimer.c:1849
 hrtimer_interrupt+0x269/0x810 kernel/time/hrtimer.c:1911
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
 __sysvec_apic_timer_interrupt+0x5f/0x1f0 arch/x86/kernel/apic/apic.c:1062
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0x32/0x80 arch/x86/kernel/apic/apic.c:1056
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697

read to 0xffff888103e31398 of 8 bytes by task 9789 on cpu 0:
 rtc_dev_poll+0x78/0xb0 drivers/rtc/dev.c:198
 vfs_poll include/linux/poll.h:82 [inline]
 io_poll_check_events io_uring/poll.c:281 [inline]
 io_poll_task_func+0x13b/0x800 io_uring/poll.c:341
 io_handle_tw_list+0x121/0x230 io_uring/tw.c:72
 tctx_task_work_run+0x42/0x170 io_uring/tw.c:132
 tctx_task_work+0x3f/0x80 io_uring/tw.c:150
 task_work_run+0x130/0x1a0 kernel/task_work.c:233
 get_signal+0xe0e/0xf60 kernel/signal.c:2807
 arch_do_signal_or_restart+0x96/0x450 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop+0x6a/0x6f0 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
 do_syscall_64+0x249/0x370 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x000000000002c3c0 -> 0x000000000002c4c0

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 9789 Comm: syz.8.1337 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
==================================================================
==================================================================
BUG: KCSAN: data-race in rtc_dev_poll / rtc_pie_update_irq

read-write to 0xffff888103e31398 of 8 bytes by interrupt on cpu 1:
 rtc_handle_legacy_irq drivers/rtc/interface.c:651 [inline]
 rtc_pie_update_irq+0x7b/0xd0 drivers/rtc/interface.c:699
 __run_hrtimer kernel/time/hrtimer.c:1785 [inline]
 __hrtimer_run_queues+0x218/0x4f0 kernel/time/hrtimer.c:1849
 hrtimer_interrupt+0x269/0x810 kernel/time/hrtimer.c:1911
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
 __sysvec_apic_timer_interrupt+0x5f/0x1f0 arch/x86/kernel/apic/apic.c:1062
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0x6f/0x80 arch/x86/kernel/apic/apic.c:1056
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
 pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:62
 arch_safe_halt arch/x86/kernel/process.c:766 [inline]
 default_idle+0x9/0x20 arch/x86/kernel/process.c:767
 default_idle_call+0x3b/0x60 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:199 [inline]
 do_idle+0x17f/0x2b0 kernel/sched/idle.c:352
 cpu_startup_entry+0x24/0x30 kernel/sched/idle.c:451
 start_secondary+0x95/0xa0 arch/x86/kernel/smpboot.c:312
 common_startup_64+0x13e/0x147

read to 0xffff888103e31398 of 8 bytes by task 9789 on cpu 0:
 rtc_dev_poll+0x78/0xb0 drivers/rtc/dev.c:198
 vfs_poll include/linux/poll.h:82 [inline]
 io_poll_check_events io_uring/poll.c:281 [inline]
 io_poll_task_func+0x13b/0x800 io_uring/poll.c:341
 io_handle_tw_list+0x121/0x230 io_uring/tw.c:72
 tctx_task_work_run+0x42/0x170 io_uring/tw.c:132
 tctx_task_work+0x3f/0x80 io_uring/tw.c:150
 task_work_run+0x130/0x1a0 kernel/task_work.c:233
 get_signal+0xe0e/0xf60 kernel/signal.c:2807
 arch_do_signal_or_restart+0x96/0x450 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop+0x6a/0x6f0 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
 do_syscall_64+0x249/0x370 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000000000ef1c0 -> 0x00000000000ef2c0

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 9789 Comm: syz.8.1337 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
==================================================================
==================================================================
BUG: KCSAN: data-race in rtc_dev_poll / rtc_pie_update_irq

read-write to 0xffff888103e31398 of 8 bytes by interrupt on cpu 1:
 rtc_handle_legacy_irq drivers/rtc/interface.c:651 [inline]
 rtc_pie_update_irq+0x7b/0xd0 drivers/rtc/interface.c:699
 __run_hrtimer kernel/time/hrtimer.c:1785 [inline]
 __hrtimer_run_queues+0x218/0x4f0 kernel/time/hrtimer.c:1849
 hrtimer_interrupt+0x269/0x810 kernel/time/hrtimer.c:1911
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
 __sysvec_apic_timer_interrupt+0x5f/0x1f0 arch/x86/kernel/apic/apic.c:1062
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0x6f/0x80 arch/x86/kernel/apic/apic.c:1056
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
 pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:62
 arch_safe_halt arch/x86/kernel/process.c:766 [inline]
 default_idle+0x9/0x20 arch/x86/kernel/process.c:767
 default_idle_call+0x3b/0x60 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:199 [inline]
 do_idle+0xe7/0x2b0 kernel/sched/idle.c:352
 cpu_startup_entry+0x24/0x30 kernel/sched/idle.c:451
 start_secondary+0x95/0xa0 arch/x86/kernel/smpboot.c:312
 common_startup_64+0x13e/0x147

read to 0xffff888103e31398 of 8 bytes by task 9789 on cpu 0:
 rtc_dev_poll+0x78/0xb0 drivers/rtc/dev.c:198
 vfs_poll include/linux/poll.h:82 [inline]
 __io_arm_poll_handler+0x1ec/0xc30 io_uring/poll.c:586
 io_poll_add+0x69/0xf0 io_uring/poll.c:904
 __io_issue_sqe+0xfd/0x2d0 io_uring/io_uring.c:1384
 io_issue_sqe+0x206/0xc00 io_uring/io_uring.c:1407
 io_queue_sqe io_uring/io_uring.c:1634 [inline]
 io_req_task_submit+0x46/0xa0 io_uring/io_uring.c:1044
 io_poll_task_func+0x60b/0x800 io_uring/poll.c:-1
 io_handle_tw_list+0x121/0x230 io_uring/tw.c:72
 tctx_task_work_run+0x42/0x170 io_uring/tw.c:132
 tctx_task_work+0x3f/0x80 io_uring/tw.c:150
 task_work_run+0x130/0x1a0 kernel/task_work.c:233
 get_signal+0xe0e/0xf60 kernel/signal.c:2807
 arch_do_signal_or_restart+0x96/0x450 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop+0x6a/0x6f0 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
 do_syscall_64+0x249/0x370 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000000001ce5c0 -> 0x00000000001ce6c0

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 9789 Comm: syz.8.1337 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
==================================================================
==================================================================
BUG: KCSAN: data-race in rtc_dev_poll / rtc_pie_update_irq

read-write to 0xffff888103e31398 of 8 bytes by interrupt on cpu 1:
 rtc_handle_legacy_irq drivers/rtc/interface.c:651 [inline]
 rtc_pie_update_irq+0x7b/0xd0 drivers/rtc/interface.c:699
 __run_hrtimer kernel/time/hrtimer.c:1785 [inline]
 __hrtimer_run_queues+0x218/0x4f0 kernel/time/hrtimer.c:1849
 hrtimer_interrupt+0x269/0x810 kernel/time/hrtimer.c:1911
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
 __sysvec_apic_timer_interrupt+0x5f/0x1f0 arch/x86/kernel/apic/apic.c:1062
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0x6f/0x80 arch/x86/kernel/apic/apic.c:1056
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
 pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:62
 arch_safe_halt arch/x86/kernel/process.c:766 [inline]
 default_idle+0x9/0x20 arch/x86/kernel/process.c:767
 default_idle_call+0x3b/0x60 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:199 [inline]
 do_idle+0x17f/0x2b0 kernel/sched/idle.c:352
 cpu_startup_entry+0x24/0x30 kernel/sched/idle.c:451
 start_secondary+0x95/0xa0 arch/x86/kernel/smpboot.c:312
 common_startup_64+0x13e/0x147

read to 0xffff888103e31398 of 8 bytes by task 9789 on cpu 0:
 rtc_dev_poll+0x78/0xb0 drivers/rtc/dev.c:198
 vfs_poll include/linux/poll.h:82 [inline]
 io_poll_check_events io_uring/poll.c:281 [inline]
 io_poll_task_func+0x13b/0x800 io_uring/poll.c:341
 io_handle_tw_list+0x121/0x230 io_uring/tw.c:72
 tctx_task_work_run+0x42/0x170 io_uring/tw.c:132
 tctx_task_work+0x3f/0x80 io_uring/tw.c:150
 task_work_run+0x130/0x1a0 kernel/task_work.c:233
 get_signal+0xe0e/0xf60 kernel/signal.c:2807
 arch_do_signal_or_restart+0x96/0x450 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop+0x6a/0x6f0 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
 do_syscall_64+0x249/0x370 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000000002951c0 -> 0x00000000002952c0

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 9789 Comm: syz.8.1337 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
==================================================================