[Qemu-devel] latest qemu with gdb remote not working

[Qemu-devel] latest qemu with gdb remote not working

[Peter Cheung]

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i start my qemu by this
~/qemu/bin/qemu-system-x86_64 -hda hd10meg.img -gdb tcp::1234 -k en-us -S -m 256m
it was working before, but not for the latest code. When i use GDB to connect to it, it show up a warning message and i was unable to start qemu. Please take a look the attachment.
thanks 		 	   		  

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Re: [Qemu-devel] latest qemu with gdb remote not working

[Peter Crosthwaite]

Hi Peter,

On Sun, Jun 2, 2013 at 6:09 AM, Peter Cheung <mcheung63@hotmail.com> wrote:
> i start my qemu by this
>
> ~/qemu/bin/qemu-system-x86_64 -hda hd10meg.img -gdb tcp::1234 -k en-us -S -m
> 256m
>
> it was working before, but not for the latest code.

When was "before" and are you able to git bisect it?

Regards,
Peter

> When i use GDB to
> connect to it, it show up a warning message and i was unable to start qemu.
> Please take a look the attachment.
>
> thanks

Re: [Qemu-devel] latest qemu with gdb remote not working

[Peter Maydell]

On 1 June 2013 23:57, Peter Crosthwaite <peter.crosthwaite@xilinx.com> wrote:
> On Sun, Jun 2, 2013 at 6:09 AM, Peter Cheung <mcheung63@hotmail.com> wrote:
>> i start my qemu by this
>>
>> ~/qemu/bin/qemu-system-x86_64 -hda hd10meg.img -gdb tcp::1234 -k en-us -S -m
>> 256m
>>
>> it was working before, but not for the latest code.
>
> When was "before" and are you able to git bisect it?

The other important question is: can you reproduce
on something other than MacOSX host?

(Also, please don't attach screenshots for error messages:
you can just cut-and-paste them into your email.)

thanks
-- PMM

Re: [Qemu-devel] latest qemu with gdb remote not working

[Peter Cheung]

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Dear Maydell    I just tried to compile the latest qemu on Fedora 18 64 bits, it is also fail. When i press "c" in gdb, the qemu won't start running.But one thing fedora is different than mac, when i connect gdb to qemu, it won't say "warning: Error 268435459 getting port names from mach_port_names"
In my mac, i use gcc from mac port, here is the version detail:
/Users/peter>gcc -vUsing built-in specs.Target: i686-apple-darwin11Configured with: /private/var/tmp/llvmgcc42/llvmgcc42-2336.1~22/src/configure --disable-checking --enable-werror --prefix=/Developer/usr/llvm-gcc-4.2 --mandir=/share/man --enable-languages=c,objc,c++,obj-c++ --program-prefix=llvm- --program-transform-name=/^[cg][^.-]*$/s/$/-4.2/ --with-slibdir=/usr/lib --build=i686-apple-darwin11 --enable-llvm=/private/var/tmp/llvmgcc42/llvmgcc42-2336.1~22/dst-llvmCore/Developer/usr/local --program-prefix=i686-apple-darwin11- --host=x86_64-apple-darwin11 --target=i686-apple-darwin11 --with-gxx-include-dir=/usr/include/c++/4.2.1Thread model: posixgcc version 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2336.1.00)
/Users/peter>ld -v@(#)PROGRAM:ld  PROJECT:ld64-134.9configured to support archs: i386 x86_64LTO support using: llvm version 3.0
Thanksfrom Peter

> From: peter.maydell@linaro.org
> Date: Sun, 2 Jun 2013 00:09:38 +0100
> Subject: Re: [Qemu-devel] latest qemu with gdb remote not working
> To: peter.crosthwaite@xilinx.com
> CC: mcheung63@hotmail.com; qemu-devel@nongnu.org
> 
> On 1 June 2013 23:57, Peter Crosthwaite <peter.crosthwaite@xilinx.com> wrote:
> > On Sun, Jun 2, 2013 at 6:09 AM, Peter Cheung <mcheung63@hotmail.com> wrote:
> >> i start my qemu by this
> >>
> >> ~/qemu/bin/qemu-system-x86_64 -hda hd10meg.img -gdb tcp::1234 -k en-us -S -m
> >> 256m
> >>
> >> it was working before, but not for the latest code.
> >
> > When was "before" and are you able to git bisect it?
> 
> The other important question is: can you reproduce
> on something other than MacOSX host?
> 
> (Also, please don't attach screenshots for error messages:
> you can just cut-and-paste them into your email.)
> 
> thanks
> -- PMM
 		 	   		  

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Re: [Qemu-devel] latest qemu with gdb remote not working

[Peter Maydell]

On 2 June 2013 06:46, Peter Cheung <mcheung63@hotmail.com> wrote:
>     I just tried to compile the latest qemu on Fedora 18 64 bits,
> it is also fail. When i press "c" in gdb, the qemu won't start
> running.

Good. This significantly increases the chances that somebody
will investigate.

> But one thing fedora is different than mac, when i connect gdb to qemu, it
> won't say "warning: Error 268435459 getting port names from mach_port_names"

That looks like a Mac GDB specific issue.

> In my mac, i use gcc from mac port, here is the version detail:
>
> /Users/peter>gcc -v

> gcc version 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2336.1.00)

This is pretty ancient -- I'd suggest using clang to build
QEMU instead. (It probably won't fix your problem here, though.)

What command line are you using to configure and build QEMU?

thanks
-- PMM

Re: [Qemu-devel] latest qemu with gdb remote not working

[Peter Crosthwaite]

Hi Peter and Peter :)

On Sun, Jun 2, 2013 at 7:27 PM, Peter Maydell <peter.maydell@linaro.org> wrote:
> On 2 June 2013 06:46, Peter Cheung <mcheung63@hotmail.com> wrote:
>>     I just tried to compile the latest qemu on Fedora 18 64 bits,
>> it is also fail. When i press "c" in gdb, the qemu won't start
>> running.
>
> Good. This significantly increases the chances that somebody
> will investigate.

I think I may have replicated as well. qemu-system-arm on Ubuntu 10.04 host.
And it works again for me after a revert of:

commit 87f25c12bfeaaa0c41fb857713bbc7e8a9b757dc
Author: Paolo Bonzini <pbonzini@redhat.com>
Date:   Thu May 30 13:20:40 2013 +0200

    gdbstub: do not restart crashed guest

    If a guest has crashed with an internal error or similar, detaching
    gdb (or any other debugger action) should not restart it.

    Cc: Jan Kiszka <jan.kiszka@siemens.com>
    Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
    Reviewed-by: Laszlo Ersek <lersek@redhat.com>
    Message-id: 1369912840-18577-1-git-send-email-pbonzini@redhat.com
    Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

Ill dig further before sending through minimal replication
instructions (gotta run!)
but Peter Cheung, can you please try your test case after reverting this commit,
to see if its perhaps the same bug?

$ git revert 87f25c12bfeaaa0c41fb857713bbc7e8a9b757dc

Regards,
Peter

>
>> But one thing fedora is different than mac, when i connect gdb to qemu, it
>> won't say "warning: Error 268435459 getting port names from mach_port_names"
>
> That looks like a Mac GDB specific issue.
>
>> In my mac, i use gcc from mac port, here is the version detail:
>>
>> /Users/peter>gcc -v
>
>> gcc version 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2336.1.00)
>
> This is pretty ancient -- I'd suggest using clang to build
> QEMU instead. (It probably won't fix your problem here, though.)
>
> What command line are you using to configure and build QEMU?
>
> thanks
> -- PMM
>

Re: [Qemu-devel] latest qemu with gdb remote not working

[Paolo Bonzini]

Il 03/06/2013 09:42, Peter Crosthwaite ha scritto:
> Hi Peter and Peter :)
> 
> On Sun, Jun 2, 2013 at 7:27 PM, Peter Maydell <peter.maydell@linaro.org> wrote:
>> On 2 June 2013 06:46, Peter Cheung <mcheung63@hotmail.com> wrote:
>>>     I just tried to compile the latest qemu on Fedora 18 64 bits,
>>> it is also fail. When i press "c" in gdb, the qemu won't start
>>> running.
>>
>> Good. This significantly increases the chances that somebody
>> will investigate.
> 
> I think I may have replicated as well. qemu-system-arm on Ubuntu 10.04 host.
> And it works again for me after a revert of:
> 
> commit 87f25c12bfeaaa0c41fb857713bbc7e8a9b757dc
> Author: Paolo Bonzini <pbonzini@redhat.com>
> Date:   Thu May 30 13:20:40 2013 +0200
> 
>     gdbstub: do not restart crashed guest
> 
>     If a guest has crashed with an internal error or similar, detaching
>     gdb (or any other debugger action) should not restart it.
> 
>     Cc: Jan Kiszka <jan.kiszka@siemens.com>
>     Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
>     Reviewed-by: Laszlo Ersek <lersek@redhat.com>
>     Message-id: 1369912840-18577-1-git-send-email-pbonzini@redhat.com
>     Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

Oops, indeed you need to type cont in both gdb and the monitor after
this patch.  Funny I didn't notice; the fix should be to use
!runstate_needs_reset() instead of runstate_check(RUN_STATE_DEBUG).

But it is likely a different bug than the Mac OS X one.

Paolo

> Ill dig further before sending through minimal replication
> instructions (gotta run!)
> but Peter Cheung, can you please try your test case after reverting this commit,
> to see if its perhaps the same bug?
> 
> $ git revert 87f25c12bfeaaa0c41fb857713bbc7e8a9b757dc
> 
> Regards,
> Peter
> 
>>
>>> But one thing fedora is different than mac, when i connect gdb to qemu, it
>>> won't say "warning: Error 268435459 getting port names from mach_port_names"
>>
>> That looks like a Mac GDB specific issue.
>>
>>> In my mac, i use gcc from mac port, here is the version detail:
>>>
>>> /Users/peter>gcc -v
>>
>>> gcc version 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2336.1.00)
>>
>> This is pretty ancient -- I'd suggest using clang to build
>> QEMU instead. (It probably won't fix your problem here, though.)
>>
>> What command line are you using to configure and build QEMU?
>>
>> thanks
>> -- PMM
>>

Re: [Qemu-devel] latest qemu with gdb remote not working

[Peter Cheung]

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Hi Peter   I just git pull the latest code, the gdb still fail to run after sending a "c" command.

Thanksfrom Peter

> Date: Mon, 3 Jun 2013 09:47:41 +0200
> From: pbonzini@redhat.com
> To: peter.crosthwaite@xilinx.com
> CC: peter.maydell@linaro.org; qemu-devel@nongnu.org; mcheung63@hotmail.com
> Subject: Re: [Qemu-devel] latest qemu with gdb remote not working
> 
> Il 03/06/2013 09:42, Peter Crosthwaite ha scritto:
> > Hi Peter and Peter :)
> > 
> > On Sun, Jun 2, 2013 at 7:27 PM, Peter Maydell <peter.maydell@linaro.org> wrote:
> >> On 2 June 2013 06:46, Peter Cheung <mcheung63@hotmail.com> wrote:
> >>>     I just tried to compile the latest qemu on Fedora 18 64 bits,
> >>> it is also fail. When i press "c" in gdb, the qemu won't start
> >>> running.
> >>
> >> Good. This significantly increases the chances that somebody
> >> will investigate.
> > 
> > I think I may have replicated as well. qemu-system-arm on Ubuntu 10.04 host.
> > And it works again for me after a revert of:
> > 
> > commit 87f25c12bfeaaa0c41fb857713bbc7e8a9b757dc
> > Author: Paolo Bonzini <pbonzini@redhat.com>
> > Date:   Thu May 30 13:20:40 2013 +0200
> > 
> >     gdbstub: do not restart crashed guest
> > 
> >     If a guest has crashed with an internal error or similar, detaching
> >     gdb (or any other debugger action) should not restart it.
> > 
> >     Cc: Jan Kiszka <jan.kiszka@siemens.com>
> >     Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> >     Reviewed-by: Laszlo Ersek <lersek@redhat.com>
> >     Message-id: 1369912840-18577-1-git-send-email-pbonzini@redhat.com
> >     Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
> 
> Oops, indeed you need to type cont in both gdb and the monitor after
> this patch.  Funny I didn't notice; the fix should be to use
> !runstate_needs_reset() instead of runstate_check(RUN_STATE_DEBUG).
> 
> But it is likely a different bug than the Mac OS X one.
> 
> Paolo
> 
> > Ill dig further before sending through minimal replication
> > instructions (gotta run!)
> > but Peter Cheung, can you please try your test case after reverting this commit,
> > to see if its perhaps the same bug?
> > 
> > $ git revert 87f25c12bfeaaa0c41fb857713bbc7e8a9b757dc
> > 
> > Regards,
> > Peter
> > 
> >>
> >>> But one thing fedora is different than mac, when i connect gdb to qemu, it
> >>> won't say "warning: Error 268435459 getting port names from mach_port_names"
> >>
> >> That looks like a Mac GDB specific issue.
> >>
> >>> In my mac, i use gcc from mac port, here is the version detail:
> >>>
> >>> /Users/peter>gcc -v
> >>
> >>> gcc version 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2336.1.00)
> >>
> >> This is pretty ancient -- I'd suggest using clang to build
> >> QEMU instead. (It probably won't fix your problem here, though.)
> >>
> >> What command line are you using to configure and build QEMU?
> >>
> >> thanks
> >> -- PMM
> >>
> 
> 
 		 	   		  

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Re: [Qemu-devel] latest qemu with gdb remote not working

[Peter Cheung]

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Hi Peter Crosthwaite    I haven't git pull the code for two months.

Thanksfrom Peter

> Date: Sun, 2 Jun 2013 08:57:37 +1000
> From: peter.crosthwaite@xilinx.com
> To: mcheung63@hotmail.com
> CC: qemu-devel@nongnu.org
> Subject: Re: [Qemu-devel] latest qemu with gdb remote not working
> 
> Hi Peter,
> 
> On Sun, Jun 2, 2013 at 6:09 AM, Peter Cheung <mcheung63@hotmail.com> wrote:
> > i start my qemu by this
> >
> > ~/qemu/bin/qemu-system-x86_64 -hda hd10meg.img -gdb tcp::1234 -k en-us -S -m
> > 256m
> >
> > it was working before, but not for the latest code.
> 
> When was "before" and are you able to git bisect it?
> 
> Regards,
> Peter
> 
> > When i use GDB to
> > connect to it, it show up a warning message and i was unable to start qemu.
> > Please take a look the attachment.
> >
> > thanks
> 
 		 	   		  

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Re: [Qemu-devel] latest qemu with gdb remote not working

[Eric Blake]

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On 06/01/2013 02:09 PM, Peter Cheung wrote:
> i start my qemu by this
> ~/qemu/bin/qemu-system-x86_64 -hda hd10meg.img -gdb tcp::1234 -k en-us -S -m 256m
> it was working before, but not for the latest code. When i use GDB to connect to it, it show up a warning message and i was unable to start qemu. Please take a look the attachment.
> thanks 		 	   		  

Posting 1 megabyte screenshots is considered poor netiquette - your 1M
incoming is multiplied to several hundred megabytes outgoing based on
the large number of subscribers to this list, which puts a burden on the
mail server.  Then, not everyone has cheap fast internet connections,
and downloading a megabyte message is not trivial.  And several list
readers prefer to see only plain text emails by default, where your
screenshot requires lots of extra work to even see what you are talking
about.  Please, don't send images when a copy-and-paste of the terminal
contents will do; or at a minimum consider posting the screenshot to a
website then posting only the URL to that website in your mail message.

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org


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Re: [Qemu-devel] latest qemu with gdb remote not working

[Peter Cheung]

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Sorry about that, i forgot i am in a mailing list


> Date: Mon, 3 Jun 2013 06:19:56 -0600
> From: eblake@redhat.com
> To: mcheung63@hotmail.com
> CC: qemu-devel@nongnu.org
> Subject: Re: [Qemu-devel] latest qemu with gdb remote not working
> 
> On 06/01/2013 02:09 PM, Peter Cheung wrote:
> > i start my qemu by this
> > ~/qemu/bin/qemu-system-x86_64 -hda hd10meg.img -gdb tcp::1234 -k en-us -S -m 256m
> > it was working before, but not for the latest code. When i use GDB to connect to it, it show up a warning message and i was unable to start qemu. Please take a look the attachment.
> > thanks 		 	   		  
> 
> Posting 1 megabyte screenshots is considered poor netiquette - your 1M
> incoming is multiplied to several hundred megabytes outgoing based on
> the large number of subscribers to this list, which puts a burden on the
> mail server.  Then, not everyone has cheap fast internet connections,
> and downloading a megabyte message is not trivial.  And several list
> readers prefer to see only plain text emails by default, where your
> screenshot requires lots of extra work to even see what you are talking
> about.  Please, don't send images when a copy-and-paste of the terminal
> contents will do; or at a minimum consider posting the screenshot to a
> website then posting only the URL to that website in your mail message.
> 
> -- 
> Eric Blake   eblake redhat com    +1-919-301-3266
> Libvirt virtualization library http://libvirt.org
> 
 		 	   		  

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