[Lguest] lguest: mapping switcher would thwack fixmap

[Paul Bolle]

On Wed, 2013-04-17 at 11:38 +0930, Rusty Russell wrote:
> OK, I did some cleanups along the way, but this seems to work for me.
> 
> You can either grab my pending-rebases branch from git.kernel.org (which
> has all my pending patches in it), or apply the following mega-patch
> which should be equivalent.
> 
> Please report back if this fixes the problem for you...

0) The mega-patch applied cleanly on top of v3.8.8-rc1 (which I'm
running now).

1) After updating (the relevant copy of) arch/x86/include/asm/lguest.h
in /usr/src/kernels it sufficed to rebuilt the lg module (as all other
changes were in drivers/lguest).

2) Th lg module now loads without incident:
    lguest: mapped switcher at ffd31000

And running the lguest tool doesn't reboot the system anymore:
    sudo ./lguest -v 128 [...]/vmlinux
    Guest base is at 0xaf613000
    Virtqueue page 0x8001000
    Virtqueue page 0x8004000
    device 1: console
    Section 0: size 8052736 addr 0x400000
    Section 1: size 3411968 addr 0xbae000
    Guest: 0xaf613000 - 0xb761a000 (0x8007000)
    lguest: unhandled trap 13 at 0x400062 (0x0)
    Resetting device console

3) I'll search the mailing list archive for the "unhandled trap" error.
That looks familiar. I'm guessing it's not introduced by this patch.

Thanks!


Paul Bolle