Re: current xen/stable 2.6.32.9 failed upgrade from 2.6.31.6

[Josip Rodin <joy@entuzijast.net>]

On Fri, Mar 12, 2010 at 01:09:14PM +0100, Josip Rodin wrote:
> On Fri, Mar 12, 2010 at 12:41:39PM +0100, Josip Rodin wrote:
> > And now here goes the whole output preceding the 2.6.32 crash:
> [...]
> > In the meantime there was another update to the stable branch, I'll go
> > compile that...
> 
> The symptoms remained the same, only the CPU MHz calculation and some memory
> offsets are different.
> 
> (XEN) mm.c:720:d0 Bad L1 flags 800000
> (XEN) mm.c:4221:d0 ptwr_emulate: could not get_page_from_l1e()
> (XEN) d0:v0: unhandled page fault (ec=0003)
> (XEN) Pagetable walk from ffff8800014fdfd8:
> (XEN)  L4[0x110] = 0000000115002067 0000000000001002
> (XEN)  L3[0x000] = 0000000115006067 0000000000001006
> (XEN)  L2[0x00a] = 0000000116c8a067 0000000000002c8a 
> (XEN)  L1[0x0fd] = 00100001154fd065 00000000000014fd
> (XEN) domain_crash_sync called from entry.S
> (XEN) Domain 0 (vcpu#0) crashed on cpu#0:
> (XEN) ----[ Xen-3.4  x86_64  debug=n  Not tainted ]----

FWIW I tried to git bisect this in the last couple of days, but the result
turned out to be fairly obvious and useless as after 14 bisections
I only came to this:

commit 18ecfad3aaeead019b0e07078f643deaa7d10d44
    x86: make /dev/mem mappings _PAGE_IOMAP
commit 56f27a6d47275f6dc94adf3ecc5fe958cdcdebee
    xen/dom0: add XEN_DOM0 config option

I didn't follow through with the last bisection, it had seemed increasingly
futile for a while now... :)

I saw a peculiar side effect at one point, when I went back to a random
working 2.6.31.1 dom0, all userland processes started crashing with Illegal
instruction. One iLO reset later, it's all good again. I'm guessing it was
a transient broken state.

And then when I gave up and updated to latest xen/stable for one last try,
that was the biggest d'oh moment - it's fixed :) Was it de67ec8b?

-- 
     2. That which causes joy or happiness.