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BUG: KCSAN: data-race in hrtimer_reprogram / print_cpu

write to 0xffff888237d1b768 of 8 bytes by task 23148 on cpu 1:
 __hrtimer_reprogram kernel/time/hrtimer.c:713 [inline]
 hrtimer_reprogram+0x183/0x290 kernel/time/hrtimer.c:899
 hrtimer_start_range_ns_user+0xfa/0x150 kernel/time/hrtimer.c:1581
 hrtimer_start_expires_user include/linux/hrtimer.h:248 [inline]
 common_hrtimer_rearm+0x85/0x90 kernel/time/posix-timers.c:296
 __posixtimer_deliver_signal kernel/time/posix-timers.c:317 [inline]
 posixtimer_deliver_signal+0x103/0x350 kernel/time/posix-timers.c:348
 dequeue_signal+0x296/0x370 kernel/signal.c:660
 get_signal+0x356/0xf10 kernel/signal.c:2926
 arch_do_signal_or_restart+0x96/0x480 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
 exit_to_user_mode_loop+0x15d/0x8c0 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x23c/0x3c0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237d1b768 of 8 bytes by task 23167 on cpu 0:
 print_cpu+0x2fb/0x5d0 kernel/time/timer_list.c:129
 timer_list_show+0x107/0x170 kernel/time/timer_list.c:287
 seq_read_iter+0x5f6/0x8f0 fs/seq_file.c:273
 proc_reg_read_iter+0x110/0x180 fs/proc/inode.c:299
 copy_splice_read+0x47a/0x6b0 fs/splice.c:362
 do_splice_read fs/splice.c:980 [inline]
 splice_direct_to_actor+0x261/0x680 fs/splice.c:1084
 do_splice_direct_actor fs/splice.c:1202 [inline]
 do_splice_direct+0x119/0x1a0 fs/splice.c:1228
 do_sendfile+0x37d/0x640 fs/read_write.c:1371
 __do_sys_sendfile64 fs/read_write.c:1432 [inline]
 __se_sys_sendfile64 fs/read_write.c:1418 [inline]
 __x64_sys_sendfile64+0x105/0x150 fs/read_write.c:1418
 x64_sys_call+0x2dc4/0x3020 arch/x86/include/generated/asm/syscalls_64.h:41
 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: 0x00000058582f75dc -> 0x00000058582bc12e

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 23167 Comm: syz.0.7065 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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