From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeremy Fitzhardinge <jeremy@goop.org>
Subject: Re: pvops DomU kernels [was Re: "Hotplug Scripts not
	working ..." error on jaunty]
Date: Fri, 23 Oct 2009 13:37:08 -0700
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To: Dulloor <dulloor@gmail.com>
Cc: Boris Derzhavets <bderzhavets@yahoo.com>, Xen-devel <xen-devel@lists.xensource.com>, "Marc - A. Dahlhaus" <mad@wol.de>, Keir Fraser <keir.fraser@eu.citrix.com>
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On 10/23/09 01:21, Dulloor wrote:
> * jeremy pvops git (with SMP) - Your patch works. I had commented out
> detect_extended_topology as a work-around.
>   

OK, good.

> * jeremy pvops git (without SMP) - Build fails at link time, since
> "register_task_migration_notifier" definition is guarded by CONFIG_SMP
> (rightly so). This function is used in pvclock_init_vsyscall. Should
> the call in pvclock_init_vsyscall be guarded by CONFIG_SMP or should
> another "dummy" version of register_task_migration_notifier be defined
> for !CONFIG_SMP.
>   

Yes, the second sounds like the right answer.

> * Linus' git - Nothing on Linux console. Crash rip [BUG()] -
> (gdb) x/i 0xffffffff818da4ee
> 0xffffffff818da4ee <xen_load_gdt_boot+272>:     ud2a
>
> Crash is because HYPERVISOR_update_va_mapping fails.
>
> I have attached the "xm dmesg", which also shows the error(in mm.c)
> leading to the crash. If you can't think of any existing problem, I
> will spend time debugging tomorrow.
>   

Its not at all clear to me what Xen is objecting to here.  There are a
few paths where it can end up at could_not_pin in get_page_from_l1e(),
but I don't know which one is happening here.  I think it's the "if (
unlikely(real_pg_owner != pg_owner) )" conditional, but I don't know
what real_pg_owner means here.

Keir?

    J