Re: [BUG] XEN 4.3.3 - segfault in xl create for HVM with PCI passthrough

[Ian Campbell <Ian.Campbell@citrix.com>]

On Tue, 2014-11-04 at 18:30 +0100, Atom2 wrote:
> Am 04.11.14 um 17:31 schrieb Ian Campbell:
> > On Tue, 2014-11-04 at 17:14 +0100, Atom2 wrote:
> >> Am 04.11.14 um 16:44 schrieb Ian Campbell:
> >>> On Tue, 2014-11-04 at 16:13 +0100, Atom2 wrote:
> >>> You could try running the xl command under valgrind, you may find "xl
> >>> create -F" (which keeps xl in the foreground) handy if you try this.
> >>> That might help catch any heap corruption etc.
> >> I don't know what valgrind is, but I'll have a look and see how to deal
> >> with that ...
> >
> > Valgrind is a totally awesome memory allocation debugger ;-)
> >
> In the attached file named 'valgrind 'please find the output of
> 	# valgrind xl create -F -c pfsense

Sadly it looks like your version of valgrind doesn't know how to handle
the hypercalls made by the Xen toolstack, which means it produces a lot
of unrelated noise.

You seem to be using valgrind 3.9.0, which lacked knowledge of some of
the HVM related hypercalls that weren't added until 3.10.0. It's
probably not worth pursuing this angle any further (unless it is utterly
trivial to pull in the new version).

Apart from the valgrind output there is a new message from libxl:
        libxl: error: libxl_pci.c:1045:libxl__device_pci_add: PCI device 0000:04:00.0 cannot be assigned - no IOMMU?
which suggests that it isn't passing things through (this might be
fallout from valgrind not understanding things) and no segfault.

OOI what does "xl create -F ..." do without valgrind (I'm wondering if
-F is responsible for the change in behaviour).

> There's a lot of information in that file which is above my current 
> level of expertise, but I am sure you are able to make sense out of it.
> 
> BTW the stuff at lines 6 and 111 to 119 is the usual output of the xl 
> command before it segfaults.
> 
> Thanks Atom2