On Mon, Aug 14, 2017 at 05:44:00AM -0600, Jan Beulich wrote: > >>> On 14.08.17 at 13:31, <h...@posteo.de> wrote: > > On Mon, 31 Jul 2017 12:12:45 +0200, Jan Beulich <jbeul...@suse.com> wrote: > >>>>> "Andreas Kinzler" <ml...@hfp.de> 07/17/17 6:32 PM >>> > >>>>> Jan, I still have access to the hardware so perhaps we can finally > >>>>> solve > >>>>> this problem. > >>>> Feel free to go ahead; I'll be on vacation for the next three weeks. > >>> Perhaps we can shortcut debugging a bit because I looked through the > >>> patches of XenServer 7.2 and found the attached patch. Now I tried it > >>> and > >>> it seems to solve all the problems. Does that patch look good to you, > >>> too? > >> Iirc the patch had even been submitted once, and rejected as being not > >> generally correct (i.e. it cures a symptom rather than the cause). What > >> we'd need to know is the order of actions the guest takes which ought to > >> result in the vector getting unmasked, but doesn't in reality. > > > > I defined XEN_PT_LOGGING_ENABLED in xen_pt.h as requested without the > > "hack" patch. Log is attached. Does it help? > > It tells me that there's nothing unexpected on that side. As I think I > had indicated before, we really need to see both sides (qemu and > hypervisor), as part of the MSI-X handling lives in Xen. And for the > hypervisor side it is unlikely that we'll be able to get away without > a debugging patch. I am intending to make such available to you in > case you can't do so yourself, but I can't currently predict when I'll > get to it.
I think the problem is that pci_msi_conf_write_intercept is failing to unmask the entries when MSI-X is enabled with entries already configured, but this will require some debugging patch as Jan said. Following the MSI-X code is quite complicated, this split brain between Xen and QEMU makes it quite hard. I can try to come up with a patch later. Roger. _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org https://lists.xen.org/xen-devel