Re: bin/54029: gdb attach says "Couldn't get registers: Device busy"

[christos%zoulas.com@localhost (Christos Zoulas)]

On Mar 1,  5:00pm, gson%gson.org@localhost (Andreas Gustafsson) wrote:
-- Subject: bin/54029: gdb attach says "Couldn't get registers: Device busy"

[1:28pm] 485#ps -ax | grep getty
 1942 ttyE0 Is+     0:00.01 /usr/libexec/getty Pc ttyE0 
 1915 ttyE1 Is+     0:00.01 /usr/libexec/getty Pc ttyE1 
 1658 ttyE2 Is+     0:00.01 /usr/libexec/getty Pc ttyE2 
 1774 ttyE3 Is+     0:00.01 /usr/libexec/getty Pc ttyE3 
[1:28pm] 486#gdb /usr/libexec/getty 
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Reading symbols from /usr/libexec/getty...Reading symbols from /usr/libdata/debug//usr/libexec/getty.debug...done.
done.
(gdb) attach 1942
Attaching to program: /usr/libexec/getty, process 1942
Couldn't get registers: Device busy.
(gdb) [New LWP 1 of process 1942]
Reading symbols from /usr/lib/libutil.so.7...Reading symbols from /usr/libdata/debug//usr/lib/libutil.so.7.24.debug...done.
done.
Reading symbols from /usr/lib/libterminfo.so.1...Reading symbols from /usr/libdata/debug//usr/lib/libterminfo.so.1.0.debug...done.
done.
Reading symbols from /usr/lib/libc.so.12...Reading symbols from /usr/libdata/debug//usr/lib/libc.so.12.211.debug...done.
done.
Reading symbols from /usr/libexec/ld.elf_so...Reading symbols from /usr/libdata/debug//usr/libexec/ld.elf_so.debug...done.
done.
[Switching to LWP 1 of process 1942]
0x00007eb8aea3e98a in read () from /usr/lib/libc.so.12

(gdb) q
A debugging session is active.

        Inferior 1 [process 1942] will be detached.

Quit anyway? (y or n) y
Detaching from program: /usr/libexec/getty, process 1942
[1:28pm] 487#uname -a
NetBSD quasar.astron.com 8.99.34 NetBSD 8.99.34 (QUASAR) #12: Mon Feb 25 14:36:24 EST 2019  christos%quasar.astron.com@localhost:/usr/src/sys/arch/amd64/compile/QUASAR amd64