assertion failed: !profiler_queue

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: d8ea787e 9ns: don't pass user pointers for 'spec'
git tree: akaros
console output: https://syzkaller.appspot.com/x/log.txt?x=16315c58a00000
kernel config: https://syzkaller.appspot.com/x/.config?x=bc709c3b83482973
dashboard link: https://syzkaller.appspot.com/bug?extid=e8998ed113c341947438

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

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+e8998e...@syzkaller.appspotmail.com

kernel panic at kern/src/profiler.c:416, from core 3: assertion
failed: !profiler_queue
Stack Backtrace on Core 3:
#01 [<0xffffffffc200a42c>] in backtrace at src/kdebug.c:235
#02 [<0xffffffffc2009bc5>] in _panic at src/init.c:268
#03 [<0xffffffffc204624b>] in profiler_setup at src/profiler.c:416
#04 [<0xffffffffc207c4ca>] in kprof_open at drivers/dev/kprof.c:230
#05 [<0xffffffffc2033ba0>] in __namec_from at src/ns/chan.c:1268
#06 [<0xffffffffc2034393>] in namec at src/ns/chan.c:1562
#07 [<0xffffffffc20417e6>] in sysopenat at src/ns/sysfile.c:572
#08 [<0xffffffffc20592bf>] in sys_openat at src/syscall.c:1806
#09 [<0xffffffffc2059f49>] in syscall at src/syscall.c:2578
#10 [<0xffffffffc205aaf8>] in run_local_syscall at src/syscall.c:2615
#11 [<0xffffffffc205b039>] in prep_syscalls at src/syscall.c:2635
#12 [<0xffffffffc20ac812>] in sysenter_callwrapper at arch/x86/trap.c:877


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