INFO: task syz-executor.2:10413 can't die for more than 143 seconds.
task:syz-executor.2  state:R  running task     stack:25824 pid:10413 ppid:  8459 flags:0x00004006
Call Trace:
 context_switch kernel/sched/core.c:4373 [inline]
 __schedule+0x90c/0x21a0 kernel/sched/core.c:5124
 preempt_schedule_irq+0x4e/0x90 kernel/sched/core.c:5386
 irqentry_exit_cond_resched kernel/entry/common.c:403 [inline]
 irqentry_exit_cond_resched kernel/entry/common.c:395 [inline]
 irqentry_exit+0x7a/0xa0 kernel/entry/common.c:433
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:628
==================================================================
BUG: KASAN: stack-out-of-bounds in deref_stack_regs arch/x86/kernel/unwind_orc.c:370 [inline]
BUG: KASAN: stack-out-of-bounds in unwind_next_frame+0x19f8/0x1f90 arch/x86/kernel/unwind_orc.c:544
Read of size 8 at addr ffffc9000243fa88 by task khungtaskd/1663

CPU: 0 PID: 1663 Comm: khungtaskd Not tainted 5.11.0-rc3-next-20210118-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x107/0x163 lib/dump_stack.c:120
 print_address_description.constprop.0.cold+0x5/0x2f8 mm/kasan/report.c:230
 __kasan_report mm/kasan/report.c:397 [inline]
 kasan_report.cold+0x79/0xd5 mm/kasan/report.c:414
 deref_stack_regs arch/x86/kernel/unwind_orc.c:370 [inline]
 unwind_next_frame+0x19f8/0x1f90 arch/x86/kernel/unwind_orc.c:544
 show_trace_log_lvl+0x1dd/0x2ba arch/x86/kernel/dumpstack.c:293
 sched_show_task kernel/sched/core.c:7168 [inline]
 sched_show_task+0x443/0x590 kernel/sched/core.c:7142
 check_killed_task kernel/hung_task.c:183 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:241 [inline]
 watchdog.cold+0xd8/0x248 kernel/hung_task.c:338
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296


Memory state around the buggy address:
 ffffc9000243f980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc9000243fa00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f1
>ffffc9000243fa80: f1 f1 f1 00 00 f3 f3 00 00 00 00 00 00 00 00 00
                      ^
 ffffc9000243fb00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc9000243fb80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f1
==================================================================