Description of problem:

+ sudo perf record --call-graph dwarf -p 657298 /home/rjones/d/libnbd/run nbdcopy nbd://localhost null:
[ perf record: Woken up 2516 times to write data ]
[ perf record: Captured and wrote 630.839 MB perf.data (78032 samples) ]
+ sudo perf script > out.perf
perf: util/unwind-libdw.c:30: __find_debuginfo: Assertion `dso' failed.

Version-Release number of selected component (if applicable):

perf-5.11.0-1.fc35.x86_64
libdwarves1-1.20-1.fc34.x86_64

How reproducible:

100% (for me)

Steps to Reproduce:
1. I cannot reproduce this except with the single perf session I am running.

Core was generated by `perf script'.
Program terminated with signal SIGABRT, Aborted.
#0  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:49
49	  return ret;

(gdb) bt
#0  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:49
#1  0x00007fab96b838a4 in __GI_abort () at abort.c:79
#2  0x00007fab96b83789 in __assert_fail_base (fmt=<optimized out>, 
    assertion=<optimized out>, file=<optimized out>, line=<optimized out>, 
    function=<optimized out>) at assert.c:92
#3  0x00007fab96b92a16 in __GI___assert_fail (
    assertion=assertion@entry=0x5645cdc1ad2d "dso", 
    file=file@entry=0x5645cdc25089 "util/unwind-libdw.c", line=line@entry=30, 
    function=function@entry=0x5645cdc10750 <__PRETTY_FUNCTION__.0> "__find_debuginfo") at assert.c:101
#4  0x00005645cdaba36c in __find_debuginfo (mod=<optimized out>, 
    userdata=<optimized out>, modname=<optimized out>, base=<optimized out>, 
    file_name=<optimized out>, debuglink_file=<optimized out>, 
    debuglink_crc=482130406, debuginfo_file_name=0x5645d0902d88)
    at util/unwind-libdw.c:30
#5  __find_debuginfo (mod=<optimized out>, userdata=<optimized out>, 
    modname=<optimized out>, base=<optimized out>, file_name=<optimized out>, 
    debuglink_file=<optimized out>, debuglink_crc=482130406, 
    debuginfo_file_name=0x5645d0902d88) at util/unwind-libdw.c:23
#6  0x00007fab973e1d7c in find_debuginfo.part () from /lib64/libdw.so.1
#7  0x00007fab973e2b3b in dwfl_module_getdwarf () from /lib64/libdw.so.1
#8  0x00007fab973e8eb5 in dwfl_module_dwarf_cfi () from /lib64/libdw.so.1
#9  0x00007fab973f19f1 in __libdwfl_frame_unwind () from /lib64/libdw.so.1
#10 0x00007fab973f1bd0 in dwfl_frame_pc () from /lib64/libdw.so.1
#11 0x00005645cdab9ff0 in frame_callback (state=0x5645d09029f0, 
    arg=0x5645d065a060) at util/unwind-libdw.c:205
#12 0x00007fab973efe33 in dwfl_thread_getframes () from /lib64/libdw.so.1
#13 0x00007fab973ef93b in get_one_thread_cb () from /lib64/libdw.so.1
#14 0x00007fab973efc72 in dwfl_getthreads () from /lib64/libdw.so.1
#15 0x00007fab973f01b7 in dwfl_getthread_frames () from /lib64/libdw.so.1
#16 0x00005645cdaba514 in unwind__get_entries (
    cb=cb@entry=0x5645cda1f1b0 <unwind_entry>, arg=arg@entry=0x7fab961bbc98, 
    thread=0x5645d0663c40, data=data@entry=0x7ffd348d8410, max_stack=127, 
    max_stack@entry=22085) at util/unwind-libdw.c:258
#17 0x00005645cda25a97 in thread__resolve_callchain_unwind (
    evsel=0x5645cf78b1c0, max_stack=22085, sample=0x7ffd348d8410, 
    cursor=0x7fab961bbc98, thread=<optimized out>) at util/machine.c:2890
#18 0x00005645cd96a14c in process_event (machine=<optimized out>, 
    al=0x7ffd348d81e0, evsel=0x5645cf78b1c0, sample=<optimized out>, 
    script=<optimized out>) at builtin-script.c:2007
#19 process_sample_event (machine=<optimized out>, evsel=0x5645cf78b1c0, 
    sample=<optimized out>, event=<optimized out>, tool=<optimized out>)
    at builtin-script.c:2171
#20 process_sample_event (tool=<optimized out>, event=<optimized out>, 
    sample=<optimized out>, evsel=0x5645cf78b1c0, machine=<optimized out>)
    at builtin-script.c:2131
#21 0x00005645cda2c1ee in perf_session__deliver_event (session=0x5645cf79ff50, 
    event=0x7fab70b7fe10, tool=0x7ffd348d9190, file_offset=44219920)
    at util/session.c:1546
#22 0x00005645cda2fed1 in do_flush (show_progress=false, oe=0x5645cf7a6b00)
    at util/ordered-events.c:244
#23 __ordered_events__flush (oe=0x5645cf7a6b00, how=OE_FLUSH__ROUND, 
    timestamp=<optimized out>) at util/ordered-events.c:323
#24 0x00005645cda2c5ad in perf_session__process_user_event (
    session=session@entry=0x5645cf79ff50, event=event@entry=0x7fab70bf8268, 
    file_offset=file_offset@entry=44712552) at util/session.c:1598
#25 0x00005645cda2cddb in perf_session__process_event (file_offset=44712552, 
    event=0x7fab70bf8268, session=0x5645cf79ff50) at util/session.c:1758
#26 0x00005645cda2e6ba in reader__process_events (prog=0x7ffd348d9030, 
    session=0x5645cf79ff50, rd=<synthetic pointer>) at util/session.c:2221
#27 __perf_session__process_events (session=0x5645cf79ff50)
    at util/session.c:2278
#28 perf_session__process_events (session=0x5645cf79ff50)
    at util/session.c:2311
#29 0x00005645cd96ece7 in __cmd_script (script=0x7ffd348d9190)
    at builtin-script.c:2558
#30 cmd_script (argc=<optimized out>, argv=<optimized out>)
    at builtin-script.c:3957
#31 0x00005645cd9cb930 in run_builtin (p=0x5645cdf67e98 <commands+408>, 
    argc=1, argv=0x7ffd348db030) at perf.c:312
#32 0x00005645cd93715f in handle_internal_command (argv=0x7ffd348db030, argc=1)
    at perf.c:364
#33 run_argv (argv=<synthetic pointer>, argcp=<synthetic pointer>)
    at perf.c:408
#34 main (argc=1, argv=0x7ffd348db030) at perf.c:538