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BUG: KCSAN: data-race in hrtimer_interrupt / print_cpu

write to 0xffff888237d1ae60 of 8 bytes by interrupt on cpu 1:
 hrtimer_interrupt+0x193/0x460 kernel/time/hrtimer.c:1879
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x5c/0x1d0 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0x6f/0x80 arch/x86/kernel/apic/apic.c:1049
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
 kcsan_setup_watchpoint+0x415/0x430 kernel/kcsan/core.c:705
 bpf_net_ctx_clear include/linux/filter.h:803 [inline]
 bpf_test_run+0x209/0x490 net/bpf/test_run.c:436
 bpf_prog_test_run_skb+0x834/0xbd0 net/bpf/test_run.c:1093
 bpf_prog_test_run+0x207/0x390 kernel/bpf/syscall.c:4427
 __sys_bpf+0x3dc/0x790 kernel/bpf/syscall.c:5852
 __do_sys_bpf kernel/bpf/syscall.c:5941 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5939 [inline]
 __x64_sys_bpf+0x41/0x50 kernel/bpf/syscall.c:5939
 x64_sys_call+0x2478/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:322
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237d1ae60 of 8 bytes by task 5259 on cpu 0:
 print_cpu+0x30b/0x680 kernel/time/timer_list.c:133
 timer_list_show+0x107/0x170 kernel/time/timer_list.c:295
 seq_read_iter+0x316/0x940 fs/seq_file.c:230
 proc_reg_read_iter+0x10d/0x180 fs/proc/inode.c:299
 copy_splice_read+0x3c1/0x5f0 fs/splice.c:363
 do_splice_read fs/splice.c:979 [inline]
 splice_direct_to_actor+0x26c/0x680 fs/splice.c:1083
 do_splice_direct_actor fs/splice.c:1201 [inline]
 do_splice_direct+0xda/0x150 fs/splice.c:1227
 do_sendfile+0x380/0x640 fs/read_write.c:1368
 __do_sys_sendfile64 fs/read_write.c:1429 [inline]
 __se_sys_sendfile64 fs/read_write.c:1415 [inline]
 __x64_sys_sendfile64+0x105/0x150 fs/read_write.c:1415
 x64_sys_call+0xb39/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000fc7f2ae0c -> 0x0000000fc800b900

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 5259 Comm: syz.2.620 Not tainted 6.15.0-rc5-syzkaller-00123-g2c89c1b655c0 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
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