[uml-user] Query about core dump file generated by UML boot (uml survives and continues)

[Kieran G. <kie...@gm...>]

Hey all,

I just compiled uml of the linux-next tree (at commit
3979da72b0f2453dcf625e8ba4a8085e9562523b) using distcc, in case that
shouldn't be using for kernel builds as well as 3.8.0-rc1 without distcc
and I get a core file generated during boot process on host.

config file for both versions and start up info for linux-next of uml
processes attached.

I'm booting with an image of Debian 6.0 (straight from debootstrap with
stable, plus installed vim, and some other goodies on it, plus nginx),
it creates a core file on host, uml keeps booting and shows no message
at all about why the core file is generated.

GDB says for linux-next:

Core was generated by `./linux-3.8.0-rc1-next-20121224-uml mem=512M
ubd0=./fs eth0=tuntap,tap0'.
Program terminated with signal 11, Segmentation fault.
#0  0x00000000600371e5 in sigsuspend (set=0x7f37df50) at
kernel/signal.c:3329
3329        current->saved_sigmask = current->blocked;
(gdb) bt full
#0  0x00000000600371e5 in sigsuspend (set=0x7f37df50) at
kernel/signal.c:3329
No locals.
#1  0x0000000060015504 in winch_thread (arg=<optimised out>)
    at arch/um/drivers/chan_user.c:210
        data = <optimised out>
        sigs = {__val = {18446744067132882943,
            18446744073709551615 <repeats 15 times>}}
        pty_fd = 16
        pipe_fd = 18
        count = <optimised out>
        c = 1 '\001'
#2  0x000000006027e599 in clone ()
No symbol table info available.
#3  0x0000000000000000 in ?? ()

And for 3.8.0-rc1:
Core was generated by `./linux-3.8.0-rc1-uml mem=512M ubd0=./fs
eth0=tuntap,tap0'.
Program terminated with signal 11, Segmentation fault.
#0  0x0000000060047ba0 in sigsuspend (set=0x81291f40) at
kernel/signal.c:3329
3329        current->saved_sigmask = current->blocked;
(gdb) bt full
#0  0x0000000060047ba0 in sigsuspend (set=0x81291f40) at
kernel/signal.c:3329
No locals.
#1  0x000000006001d86e in winch_thread (arg=<optimised out>) at
arch/um/drivers/chan_user.c:210
        data = <optimised out>
        sigs = {__val = {18446744067132882943, 18446744073709551615
<repeats 15 times>}}
        pty_fd = <optimised out>
        pipe_fd = 21
        count = <optimised out>
        c = 1 '\001'
#2  0x0000000060303939 in clone ()
No symbol table info available.
#3  0x0000000000000000 in ?? ()
No symbol table info available.

Any ideas?

From,
Kieran Grant