gdbserver using serial port

gdbserver using serial port

[Yoriko Komatsuzaki]

Hello, 

I would like to ask you about gdbserver in case of using serial port.
In gdb-6.6, if I run gdbserver using serial port, the following messages
continue and it can't establish the connection to host gdb.

% gdbserver /dev/ttyS0 a.out
...
Remote debugging using /dev/ttyS0
readchar: Socket operation on non-socket
Remote side has terminated connection.  GDBserver will reopen the connection.
Remote debugging using /dev/ttyS0
readchar: Socket operation on non-socket
Remote side has terminated connection.  GDBserver will reopen the connection.
Remote debugging using /dev/ttyS0
readchar: Socket operation on non-socket
...

And then in gdb-6.7, the following messages are displayed. 

% gdbserver /dev/ttyS0 a.out
Process a.out created; pid = 10696
Remote debugging using /dev/ttyS0

So I ran the host gdb and tried to establish the connection between host
and target, but couldn't establish the connections channel.

In the both cases, if I use the network as the debug channel, 
I can use the gdb/gdbserver without any problems.

Do you have any ideas or comments ?

Thank you.

---
Yoriko Komatsuzaki (yoriko@sm.sony.co.jp)

Re: gdbserver using serial port

[Daniel Jacobowitz]

On Fri, Nov 02, 2007 at 11:14:13AM +0900, Yoriko Komatsuzaki wrote:
> Hello, 
> 
> I would like to ask you about gdbserver in case of using serial port.
> In gdb-6.6, if I run gdbserver using serial port, the following messages
> continue and it can't establish the connection to host gdb.

Yes, serial support was broken in gdbserver 6.6.

> % gdbserver /dev/ttyS0 a.out
> Process a.out created; pid = 10696
> Remote debugging using /dev/ttyS0
> 
> So I ran the host gdb and tried to establish the connection between host
> and target, but couldn't establish the connections channel.

Please be more specific.  What does "set debug serial 1" and "set
debug remote 1" before connecting show?

If your console is /dev/ttyS0 and a.out writes to the terminal, you
will need to redirect it, or it will interfere with communication.

-- 
Daniel Jacobowitz
CodeSourcery

Re: gdbserver using serial port

[Yoriko Komatsuzaki]

Thank you for your answer.

My environment is a littel special.

On target (gdbserver run), the serial (/dev/ttyS0) is used as the
channel. But on host (gdb run), the usb (/dev/ttyUSB0) is used.
And the host and the target is connected by "the serial/usb
transimission cable". 

So I guess that this special hardware environment might affects this
problem.

% gdb
(gdb) set debug remote 1
(gdb) set debug serial 1
(gdb) target remote /dev/ttyUSB0
Remote debugging using /dev/ttyUSB0
Sending packet: $qSupported#37...


Thank you.
---
Yoriko Komatsuzaki (yoriko@sm.sony.co.jp)

> On Fri, Nov 02, 2007 at 11:14:13AM +0900, Yoriko Komatsuzaki wrote:
> > Hello, 
> > 
> > I would like to ask you about gdbserver in case of using serial port.
> > In gdb-6.6, if I run gdbserver using serial port, the following messages
> > continue and it can't establish the connection to host gdb.
> 
> Yes, serial support was broken in gdbserver 6.6.
> 
> > % gdbserver /dev/ttyS0 a.out
> > Process a.out created; pid = 10696
> > Remote debugging using /dev/ttyS0
> > 
> > So I ran the host gdb and tried to establish the connection between host
> > and target, but couldn't establish the connections channel.
> 
> Please be more specific.  What does "set debug serial 1" and "set
> debug remote 1" before connecting show?
> 
> If your console is /dev/ttyS0 and a.out writes to the terminal, you
> will need to redirect it, or it will interfere with communication.
> 
> -- 
> Daniel Jacobowitz
> CodeSourcery

Re: gdbserver using serial port

[Daniel Jacobowitz]

On Fri, Nov 02, 2007 at 01:11:47PM +0900, Yoriko Komatsuzaki wrote:
> 
> Thank you for your answer.
> 
> My environment is a littel special.
> 
> On target (gdbserver run), the serial (/dev/ttyS0) is used as the
> channel. But on host (gdb run), the usb (/dev/ttyUSB0) is used.
> And the host and the target is connected by "the serial/usb
> transimission cable". 
> 
> So I guess that this special hardware environment might affects this
> problem.
> 
> % gdb
> (gdb) set debug remote 1
> (gdb) set debug serial 1
> (gdb) target remote /dev/ttyUSB0
> Remote debugging using /dev/ttyUSB0
> Sending packet: $qSupported#37...

This looks like either a baud rate problem, or some other complete
failure of serial support on your host.  GDB can't read even a single
byte from your target.

-- 
Daniel Jacobowitz
CodeSourcery

Re: gdbserver using serial port

[Yoriko Komatsuzaki]

Thank you for your Reply.

I checked the setting details, and I retried.
(I checked that the target serial baud-rate is 115200.)
Then I got the follwing result. But the target program does'nt execute.
I'm sorry, but could you tell me what causes like this result ?

...
(gdb) set remotebaud 115200
(gdb) set debug remote 1
(gdb) set debug serial 1
(gdb) target remote /dev/ttyUSB0
Remote debugging using /dev/ttyUSB0
Sending packet: $qSupported#37...[
r <Timeout: 2 seconds>]Sending packet: $qSupported#37...[q]putpkt: Junk: q[S]S[u]u[p]p[p]p[o]o[r]r[t]t[e]e[d]d[#]#[3]3[7]7[<Timeout: 2 seconds>]
Sending packet: $qSupported#37...[$]Packet instead of Ack, ignoring it
[q][S][u][p][p][o][r][t][e][d][#][3][7][+]Ack
[<Timeout: 2 seconds>]Timed out.
[-][<Timeout: 2 seconds>]Timed out.
[-][<Timeout: 2 seconds>]Timed out.
Ignoring packet error, continuing...
Packet qSupported (supported-packets) is supported
warning: unrecognized item "timeout" in "qSupported" response
Sending packet: $Hc-1#09...[-]Nak
Sending packet: $Hc-1#09...[+]Ack
[+][$][H][c][-][1][#][0][9]Packet received: Hc-1
Sending packet: $qC#b4...[$]Packet instead of Ack, ignoring it
[H][c][-][1][#][0][9][+]Ack
[$][q][C][#][b][4]Packet received: qC
Sending packet: $qOffsets#4b...[+]Ack
[+][$][q][O][f][f][s][e][t][s][#][4][b]Packet received: qOffsets
Malformed response to offset query, qOffsets
(gdb)


Thank you, 
Yoriko Komatsuzaki

> On Fri, Nov 02, 2007 at 01:11:47PM +0900, Yoriko Komatsuzaki wrote:
> > 
> > Thank you for your answer.
> > 
> > My environment is a littel special.
> > 
> > On target (gdbserver run), the serial (/dev/ttyS0) is used as the
> > channel. But on host (gdb run), the usb (/dev/ttyUSB0) is used.
> > And the host and the target is connected by "the serial/usb
> > transimission cable". 
> > 
> > So I guess that this special hardware environment might affects this
> > problem.
> > 
> > % gdb
> > (gdb) set debug remote 1
> > (gdb) set debug serial 1
> > (gdb) target remote /dev/ttyUSB0
> > Remote debugging using /dev/ttyUSB0
> > Sending packet: $qSupported#37...
> 
> This looks like either a baud rate problem, or some other complete
> failure of serial support on your host.  GDB can't read even a single
> byte from your target.
> 
> -- 
> Daniel Jacobowitz
> CodeSourcery

---
Yoriko Komatsuzaki (yoriko@sm.sony.co.jp)

Re: gdbserver using serial port

[Daniel Jacobowitz]

On Mon, Nov 05, 2007 at 06:53:23PM +0900, Yoriko Komatsuzaki wrote:
> (gdb) target remote /dev/ttyUSB0
> Remote debugging using /dev/ttyUSB0
> Sending packet: $qSupported#37...[
> r <Timeout: 2 seconds>]Sending packet: $qSupported#37...[q]putpkt: Junk: q[S]S[u]u[p]p[p]p[o]o[r]r[t]t[e]e[d]d[#]#[3]3[7]7[<Timeout: 2 seconds>]

Your serial port appears to be echoing what GDB sent.  Maybe the port
setup is wrong.

-- 
Daniel Jacobowitz
CodeSourcery