syzbot

=====================================================
BUG: KMSAN: uninit-value in native_apic_mem_write+0x6e/0x90 arch/x86/include/asm/apic.h:107
CPU: 1 PID: 5201 Comm: kworker/u4:4 Not tainted 5.10.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue:  0x0 (bond2)
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x21c/0x280 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:118
 __msan_warning+0x5f/0xa0 mm/kmsan/kmsan_instr.c:197
 native_apic_mem_write+0x6e/0x90 arch/x86/include/asm/apic.h:107
 apic_eoi arch/x86/include/asm/apic.h:408 [inline]
 ack_APIC_irq arch/x86/include/asm/apic.h:454 [inline]
 __sysvec_reschedule_ipi arch/x86/kernel/smp.c:227 [inline]
 sysvec_reschedule_ipi+0x7d/0x1b0 arch/x86/kernel/smp.c:225
 asm_sysvec_reschedule_ipi+0x12/0x20 arch/x86/include/asm/idtentry.h:654
RIP: 0010:finish_lock_switch+0x2b/0x40 kernel/sched/core.c:3519
Code: 48 89 e5 53 48 89 fb e8 63 39 bf 00 8b b8 88 0c 00 00 48 8b 00 48 85 c0 75 12 48 89 df e8 dd 32 bf 00 c6 00 00 c6 03 00 fb 5b <5d> c3 e8 9e 38 bf 00 eb e7 66 90 66 2e 0f 1f 84 00 00 00 00 00 55
RSP: 0018:ffff888126dd3c80 EFLAGS: 00000282
RAX: ffff88823fdb4140 RBX: ffff888128409ec0 RCX: 000000023fd14140
RDX: ffff88823fd14140 RSI: 0000000000000270 RDI: ffff88813fd95140
RBP: ffff888126dd3c80 R08: ffffea000000000f R09: ffff88813fffa000
R10: 0000000000000000 R11: 000002e0e6ce990c R12: ffff8880abf55c40
R13: ffff88812840a8c0 R14: ffff8880abf55c40 R15: ffff88813fd95140
 finish_task_switch+0xd4/0x2e0 kernel/sched/core.c:3624
 context_switch kernel/sched/core.c:3788 [inline]
 __schedule+0x51c/0x590 kernel/sched/core.c:4540
 schedule+0x270/0x330 kernel/sched/core.c:4618
 worker_thread+0x1ed9/0x2740 kernel/workqueue.c:2439
 kthread+0x51c/0x560 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Local variable ----regs@__bpf_prog_run32 created at:
 __bpf_prog_run32+0x84/0x190 kernel/bpf/core.c:1697
 __bpf_prog_run32+0x84/0x190 kernel/bpf/core.c:1697
=====================================================