Hi, Xen is getting stuck just before booting into Dom0. I dont see any unexpected messages. Anyone has faced this problem earlier. Help me to resolve this issue. <logs> (XEN) Dom0 has maximum 2 VCPUs (XEN) elf_load_binary: phdr 0 at 0xc1000000 -> 0xc12d347c (XEN) elf_load_binary: phdr 1 at 0xc12d4000 -> 0xc1347b64 (XEN) Initrd len 0x6e2400, start at 0xc1401000 (XEN) Scrubbing Free RAM: .done. (XEN) Xen trace buffers: disabled (XEN) Std. Loglevel: Errors and warnings (XEN) Guest Loglevel: Nothing (Rate-limited: Errors and warnings) (XEN) ********************************************** (XEN) ******* WARNING: CONSOLE OUTPUT IS SYNCHRONOUS (XEN) ******* This option is intended to aid debugging of Xen by ensuring (XEN) ******* that all output is synchronously delivered on the serial line. (XEN) ******* However it can introduce SIGNIFICANT latencies and affect (XEN) ******* timekeeping. It is NOT recommended for production use! (XEN) ********************************************** (XEN) 3... 2... 1... (XEN) Xen is relinquishing VGA console. (XEN) *** Serial input -> DOM0 (type ''CTRL-a'' three times to switch input to Xen). <<<<<<<<<< Nothing happens after this message </logs> Thanks, Bhaskar _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Mark Williamson
2008-Apr-02 10:46 UTC
Re: [Xen-users] Getting stuck just before booting Dom0
Hi there,> > (XEN) ******* WARNING: CONSOLE OUTPUT IS SYNCHRONOUSDid you set console output as synchronous whilst you were trying to debug this? It shouldn''t do this by default...> (XEN) Xen is relinquishing VGA console. > > (XEN) *** Serial input -> DOM0 (type ''CTRL-a'' three times to switch input > to Xen). <<<<<<<<<< Nothing happens after this message > > </logs>What''s your configuration here? I assume you''ve built your own Xen rather than using a distro-provided one? (distros usually arrange for the configuration to Just Work, which makes them the most straightforward option for most people). What versions of Xen / XenLinux are you using? How did you get them? My guess is that dom0 just isn''t sending its console output to the right place - you''re probably booting OK, you just can''t see it... Are you actually logging into this system using the serial line? Probably dom0''s console is appearing on the physical terminal but not on the serial line :-) Try adding console=xvc0 (or possibly just xvc, I can''t remember) to your *Linux* kernel command line in your grub config (adding it to the Xen line won''t work!). I think this should at least get you boot output. You''ll probably need to add "xvc0" to /etc/securetty[s ] and add a line to /etc/inittab if you want this to actually be useful for root login. Alternatively, if you already have a serial line setup for vanilla Linux, try passing "xencons=ttyS" to the Linux kernel command line, which will make the Xen console appear like a serial device (so your existing configuration should work). Cheers, Mark -- Push Me Pull You - Distributed SCM tool (http://www.cl.cam.ac.uk/~maw48/pmpu/) _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Bhaskar Muppana
2008-Apr-02 11:19 UTC
Re: [Xen-users] Getting stuck just before booting Dom0
Hi Mark,
Thanks for your reply.
I havent logged onto the machine through serial port. I am working on the
machine directly. Just to grab the xen boot messages i am using serial
console. I think problem is not with serial console. Because, i am getting
the same problem even if i dont redirect Xen to serial console. Please find
the grub configuration i am using to boot it.
title Fedora (2.6.21.7-2.fc8xen-from-srpm)
root (hd0,0)
kernel /boot/xen.gz-2.6.21.7-2.fc8 com1=115200,8n1 sync_console
noapic nolapic
module /boot/vmlinuz-2.6.21.7-2.fc8xen ro root=LABEL=/ rhgb quiet
console=ttyS0 console=tty pnpacpi=off noapic nolapic
module /boot/initrd-2.6.21.7-2.fc8xen.img
I will try to explain the problem in detail..
I am trying to boot Xen on top of a simulator. I found that there are few
issues with APIC module of that simulator. Still, Linux is able to boot
without any issues. Xen is failing to get ccr value from APIC while
booting. So, I have hardcoded this value. Now, booting is going through
without any errors, but it is getting stuck just before booting into Dom0 as
I mentioned in my previous mail.
Thanks,
Bhaskar
On 4/2/08, Mark Williamson <mark.williamson@cl.cam.ac.uk>
wrote:>
> Hi there,
>
> >
> > (XEN) ******* WARNING: CONSOLE OUTPUT IS SYNCHRONOUS
>
> Did you set console output as synchronous whilst you were trying to debug
> this? It shouldn''t do this by default...
>
> > (XEN) Xen is relinquishing VGA console.
> >
> > (XEN) *** Serial input -> DOM0 (type ''CTRL-a''
three times to switch
> input
> > to Xen). <<<<<<<<<< Nothing happens
after this message
> >
> > </logs>
>
> What''s your configuration here?
>
> I assume you''ve built your own Xen rather than using a
distro-provided
> one?
> (distros usually arrange for the configuration to Just Work, which makes
> them
> the most straightforward option for most people).
>
> What versions of Xen / XenLinux are you using? How did you get them?
>
> My guess is that dom0 just isn''t sending its console output to the
right
> place - you''re probably booting OK, you just can''t see
it...
>
> Are you actually logging into this system using the serial line? Probably
> dom0''s console is appearing on the physical terminal but not on
the serial
> line :-)
>
> Try adding console=xvc0 (or possibly just xvc, I can''t remember)
to your
> *Linux* kernel command line in your grub config (adding it to the Xen line
> won''t work!). I think this should at least get you boot output.
You''ll
> probably need to add "xvc0" to /etc/securetty[s ] and add a line
> to /etc/inittab if you want this to actually be useful for root login.
>
> Alternatively, if you already have a serial line setup for vanilla Linux,
> try
> passing "xencons=ttyS" to the Linux kernel command line, which
will make
> the
> Xen console appear like a serial device (so your existing configuration
> should work).
>
> Cheers,
> Mark
>
> --
> Push Me Pull You - Distributed SCM tool (
> http://www.cl.cam.ac.uk/~maw48/pmpu/)
>
_______________________________________________
Xen-users mailing list
Xen-users@lists.xensource.com
http://lists.xensource.com/xen-users
Mark Williamson
2008-Apr-06 20:10 UTC
Re: [Xen-users] Getting stuck just before booting Dom0
Hi Bhaskar, Sorry for the delay in getting back to you.> I havent logged onto the machine through serial port. I am working on the > machine directly. Just to grab the xen boot messages i am using serial > console. I think problem is not with serial console. Because, i am getting > the same problem even if i dont redirect Xen to serial console. Please find > the grub configuration i am using to boot it. > > title Fedora (2.6.21.7-2.fc8xen-from-srpm) > root (hd0,0) > kernel /boot/xen.gz-2.6.21.7-2.fc8 com1=115200,8n1 sync_console > noapic nolapic > module /boot/vmlinuz-2.6.21.7-2.fc8xen ro root=LABEL=/ rhgb quiet > console=ttyS0 console=tty pnpacpi=off noapic nolapic > module /boot/initrd-2.6.21.7-2.fc8xen.img > > I will try to explain the problem in detail..Well, for a start you could try getting rid of "rhgb quiet" and see if that encourages the kernel to give you any more boot output. I still think you should try redirecting kernel output directly to the Xen console and see if that comes out of the serial line (adding xencons=ttyS to your current kernel line should do the trick, I think).> I am trying to boot Xen on top of a simulator. I found that there are few > issues with APIC module of that simulator. Still, Linux is able to boot > without any issues. Xen is failing to get ccr value from APIC while > booting. So, I have hardcoded this value. Now, booting is going through > without any errors, but it is getting stuck just before booting into Dom0 > as I mentioned in my previous mail.Hmmmm. So you''re logged into the emulated serial line of the simulator, I guess? What simulator are you using? I''m not terribly familiar with this code. Xen sort-of requires an APIC. Which is to say, you''re really *supposed* to have one if you run Xen. Early versions of Xen didn''t *need* one but didn''t run as well without. I don''t know if it''s actually a supported configuration - I doubt anybody tests on non-APIC systems, so it''s quite possible that it doesn''t work :-( I realise that doesn''t help much... You might want to ask some questions on xen-devel, explaining what you''re trying to do and see if anybody has hints about what might work. Cheers, Mark> Thanks, > Bhaskar > > On 4/2/08, Mark Williamson <mark.williamson@cl.cam.ac.uk> wrote: > > Hi there, > > > > > (XEN) ******* WARNING: CONSOLE OUTPUT IS SYNCHRONOUS > > > > Did you set console output as synchronous whilst you were trying to debug > > this? It shouldn''t do this by default... > > > > > (XEN) Xen is relinquishing VGA console. > > > > > > (XEN) *** Serial input -> DOM0 (type ''CTRL-a'' three times to switch > > > > input > > > > > to Xen). <<<<<<<<<< Nothing happens after this message > > > > > > </logs> > > > > What''s your configuration here? > > > > I assume you''ve built your own Xen rather than using a distro-provided > > one? > > (distros usually arrange for the configuration to Just Work, which makes > > them > > the most straightforward option for most people). > > > > What versions of Xen / XenLinux are you using? How did you get them? > > > > My guess is that dom0 just isn''t sending its console output to the right > > place - you''re probably booting OK, you just can''t see it... > > > > Are you actually logging into this system using the serial line? > > Probably dom0''s console is appearing on the physical terminal but not on > > the serial line :-) > > > > Try adding console=xvc0 (or possibly just xvc, I can''t remember) to your > > *Linux* kernel command line in your grub config (adding it to the Xen > > line won''t work!). I think this should at least get you boot output. > > You''ll probably need to add "xvc0" to /etc/securetty[s ] and add a line > > to /etc/inittab if you want this to actually be useful for root login. > > > > Alternatively, if you already have a serial line setup for vanilla Linux, > > try > > passing "xencons=ttyS" to the Linux kernel command line, which will make > > the > > Xen console appear like a serial device (so your existing configuration > > should work). > > > > Cheers, > > Mark > > > > -- > > Push Me Pull You - Distributed SCM tool ( > > http://www.cl.cam.ac.uk/~maw48/pmpu/)-- Push Me Pull You - Distributed SCM tool (http://www.cl.cam.ac.uk/~maw48/pmpu/) _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users