[moderation] [kernel?] KCSAN: data-race in hrtimer_interrupt / print_tickdevice (14)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 7ec462100ef9 Merge tag 'pull-work.unaligned' of git://git...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11e92b9f980000
kernel config: https://syzkaller.appspot.com/x/.config?x=95098faba89c70c9
dashboard link: https://syzkaller.appspot.com/bug?extid=d4c53363703843fd81af
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [anna-...@linutronix.de fred...@kernel.org linux-...@vger.kernel.org tg...@linutronix.de]

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/9d1f2ee143e9/disk-7ec46210.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/45db6207b31a/vmlinux-7ec46210.xz
kernel image: https://storage.googleapis.com/syzbot-assets/be2fe8d55fcc/bzImage-7ec46210.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+d4c533...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in hrtimer_interrupt / print_tickdevice

write to 0xffff888237c1c218 of 8 bytes by interrupt on cpu 0:
hrtimer_interrupt+0x80/0x7b0 kernel/time/hrtimer.c:1796
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1026 [inline]
__sysvec_apic_timer_interrupt+0x5c/0x1a0 arch/x86/kernel/apic/apic.c:1043
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline]
sysvec_apic_timer_interrupt+0x6e/0x80 arch/x86/kernel/apic/apic.c:1037
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline]
acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:111
acpi_idle_do_entry+0x1d/0x30 drivers/acpi/processor_idle.c:568
acpi_idle_enter+0x96/0xb0 drivers/acpi/processor_idle.c:702
cpuidle_enter_state+0xc5/0x260 drivers/cpuidle/cpuidle.c:264
cpuidle_enter+0x40/0x70 drivers/cpuidle/cpuidle.c:385
call_cpuidle kernel/sched/idle.c:155 [inline]
cpuidle_idle_call kernel/sched/idle.c:230 [inline]
do_idle+0x195/0x230 kernel/sched/idle.c:326
cpu_startup_entry+0x25/0x30 kernel/sched/idle.c:424
rest_init+0xef/0xf0 init/main.c:747
start_kernel+0x586/0x5e0 init/main.c:1105
x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:507
x86_64_start_kernel+0x9a/0xa0 arch/x86/kernel/head64.c:488
common_startup_64+0x12c/0x137

read to 0xffff888237c1c218 of 8 bytes by task 4355 on cpu 1:
print_tickdevice+0x144/0x340 kernel/time/timer_list.c:208
timer_list_show+0x79/0x180 kernel/time/timer_list.c:300
seq_read_iter+0x2d1/0x930 fs/seq_file.c:230
proc_reg_read_iter+0x118/0x190 fs/proc/inode.c:299
copy_splice_read+0x3a0/0x5d0 fs/splice.c:365
do_splice_read fs/splice.c:985 [inline]
splice_direct_to_actor+0x269/0x670 fs/splice.c:1089
do_splice_direct_actor fs/splice.c:1207 [inline]
do_splice_direct+0xd7/0x150 fs/splice.c:1233
do_sendfile+0x39b/0x970 fs/read_write.c:1388
__do_sys_sendfile64 fs/read_write.c:1455 [inline]
__se_sys_sendfile64 fs/read_write.c:1441 [inline]
__x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1441
x64_sys_call+0xed5/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:41
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000b978d2d98 -> 0x7fffffffffffffff

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 4355 Comm: syz.2.358 Not tainted 6.12.0-rc1-syzkaller-00046-g7ec462100ef9 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
==================================================================


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