There is a widely known historical anecdote that Tsarina Catherine II wrote a simple Russian word of 3 letters with 4 errors. It is much less known that this error is not at all unique. Children of European expats studying Russian can easily write the word “hedgehog” in dictation as Y-O-Sh-E-G.
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[root@localhost test]# rpm -q drgn
drgn-0.0.11-2.fc35.x86_64
[root@localhost test]# drgn -s /usr/lib/debug/lib/modules/5.12.0-0.rc8.191.fc35.x86_64/vmlinux
Traceback (most recent call last):
File "/usr/bin/drgn", line 33, in
sys.exit(load_entry_point('drgn==0.0.11', 'console_scripts', 'drgn')())
File "/usr/lib64/python3.9/site-packages/drgn/internal/cli.py", line 119, in main
prog.load_debug_info(args.symbols, **args.default_symbols)
Exception: /usr/lib/debug/usr/lib/modules/5.12.0-0.rc8.191.fc35.x86_64/vmlinux: .debug_info+0x7704ab: unknown DWARF CU version 5
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[root@localhost ~]# crash -d 1 ( dwarf error )
...
Dwarf Error: wrong version in compilation unit header (is 5, should be 2, 3, or 4) [in module /usr/lib/debug/usr/lib/modules/5.11.12-300.fc34.x86_64/vmlinux]
crash: /usr/lib/debug/lib/modules/5.11.12-300.fc34.x86_64/vmlinux: no debugging data available
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