syzbot

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BUG: KMSAN: uninit-value in sched_clock_local kernel/sched/clock.c:272 [inline]
BUG: KMSAN: uninit-value in sched_clock_cpu+0x181/0x9c0 kernel/sched/clock.c:362
CPU: 0 PID: 4495 Comm: syz-executor1 Not tainted 4.17.0+ #9
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x188/0x2a0 mm/kmsan/kmsan.c:1125
 __msan_warning_32+0x70/0xc0 mm/kmsan/kmsan_instr.c:620
 sched_clock_local kernel/sched/clock.c:272 [inline]
 sched_clock_cpu+0x181/0x9c0 kernel/sched/clock.c:362
 update_rq_clock+0xb3/0x270 kernel/sched/core.c:206
 __schedule+0xe5/0x770 kernel/sched/core.c:3467
 schedule+0x1cc/0x2f0 kernel/sched/core.c:3568
 freezable_schedule include/linux/freezer.h:172 [inline]
 do_nanosleep+0x2c3/0x9c0 kernel/time/hrtimer.c:1689
 hrtimer_nanosleep kernel/time/hrtimer.c:1743 [inline]
 __do_sys_nanosleep kernel/time/hrtimer.c:1775 [inline]
 __se_sys_nanosleep+0x4b3/0x6a0 kernel/time/hrtimer.c:1762
 __x64_sys_nanosleep+0x92/0xc0 kernel/time/hrtimer.c:1762
 do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x4811a0
RSP: 002b:0000000000a3ea98 EFLAGS: 00000246 ORIG_RAX: 0000000000000023
RAX: ffffffffffffffda RBX: 000000000009f833 RCX: 00000000004811a0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000a3eaa0
RBP: 0000000000000000 R08: 0000000000000001 R09: 00000000018f2940
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006
R13: 0000000000000ae5 R14: 0000000000a3f160 R15: 000000000009f7cd

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:282 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:297 [inline]
 kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:689
 __msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:464
 __scd_stamp kernel/sched/clock.c:118 [inline]
 sched_clock_tick+0x3dc/0x410 kernel/sched/clock.c:382
 scheduler_tick+0x84/0x490 kernel/sched/core.c:3100
 update_process_times+0x157/0x1a0 kernel/time/timer.c:1641
 tick_sched_handle kernel/time/tick-sched.c:164 [inline]
 tick_sched_timer+0x3ba/0x520 kernel/time/tick-sched.c:1274
 __run_hrtimer kernel/time/hrtimer.c:1398 [inline]
 __hrtimer_run_queues+0xc54/0x1630 kernel/time/hrtimer.c:1460
 hrtimer_interrupt+0x451/0x13c0 kernel/time/hrtimer.c:1518
 local_apic_timer_interrupt+0x6b/0x250 arch/x86/kernel/apic/apic.c:1025
 smp_apic_timer_interrupt+0x5a/0x90 arch/x86/kernel/apic/apic.c:1053

Local variable description: ----oldbit.i@cpumask_test_cpu
Variable was created at:
 cpumask_test_cpu+0x3f/0xb0 include/linux/cpumask.h:331
 profile_tick+0x63/0xb0 kernel/profile.c:407
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