assertion failed: b->rp

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 7a1e025a vmm: reimplement the x86 instruction decoder
git tree: akaros
console output: https://syzkaller.appspot.com/x/log.txt?x=10106158e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=9b018fab5edd31b3
dashboard link: https://syzkaller.appspot.com/bug?extid=43fdeb8a82afdbf96ce5

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+43fdeb...@syzkaller.appspotmail.com

kernel panic at kern/src/ns/qio.c:1315, from core 0: assertion failed: b->rp
Stack Backtrace on Core 0:
#01 [<0xffffffffc200a7fc>] in backtrace at src/kdebug.c:235
#02 [<0xffffffffc2009f95>] in _panic at src/init.c:275
#03 [<0xffffffffc203ac03>] in read_all_blocks at src/ns/qio.c:1315
#04 [<0xffffffffc203cf74>] in qread at src/ns/qio.c:1399
#05 [<0xffffffffc2045db1>] in profiler_read at src/profiler.c:527
#06 [< [inline] >] in kprof_profdata_read at drivers/dev/kprof.c:194
#06 [<0xffffffffc207cc4d>] in kprof_read at drivers/dev/kprof.c:337
#07 [<0xffffffffc203fc0d>] in rread at src/ns/sysfile.c:772
#08 [<0xffffffffc203ff6b>] in sysread at src/ns/sysfile.c:830
#09 [<0xffffffffc20590c9>] in sys_read at src/syscall.c:1784
#10 [<0xffffffffc2059f29>] in syscall at src/syscall.c:2580
#11 [<0xffffffffc205aad8>] in run_local_syscall at src/syscall.c:2617
#12 [<0xffffffffc205b019>] in prep_syscalls at src/syscall.c:2637
#13 [<0xffffffffc20b6282>] in sysenter_callwrapper at arch/x86/trap.c:926


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.