On Wed, Nov 06, 2013 at 09:42:15PM -0400, Konrad Rzeszutek Wilk wrote: > On Wed, Nov 06, 2013 at 04:51:52PM -0700, Bjorn Helgaas wrote: > > [+cc Thomas, Ingo, Peter, x86 list] > > > > On Wed, Nov 6, 2013 at 2:16 PM, Konrad Rzeszutek Wilk > > <konrad.w...@oracle.com> wrote: > > > Certain platforms do not allow writes in the MSI-X bars > > > to setup or tear down vector values. To combat against > > > the generic code trying to write to that and either silently > > > being ignored or crashing due to the pagetables being marked r/o > > > this patch introduces a platform over-write. > > > > > > Note that we keep two separate, non-weak, functions > > > default_mask_msi_irqs() and default_mask_msix_irqs() for the > > > behavior of the arch_mask_msi_irqs() and arch_mask_msix_irqs(), > > > as the default behavior is needed by x86 PCI code. > > > > > > For Xen, which does not allow the guest to write to MSI-X > > > tables - as the hypervisor is solely responsible for setting > > > the vector values - we implement two nops. > > > > > > CC: Bjorn Helgaas <bhelg...@google.com> > > > CC: Sucheta Chakraborty <sucheta.chakrabo...@qlogic.com> > > > CC: Zhenzhong Duan <zhenzhong.d...@oracle.com> > > > Signed-off-by: Konrad Rzeszutek Wilk <konrad.w...@oracle.com> > > > > I think this is safe, and I'd like to squeeze it into the v3.13 merge > > window next week, since it supersedes three patches Zhenzhong has been > > trying to get in since July [1], and this patch is much simpler to > > understand. > > > > I *think* this also fixes an actual bug on Xen. Konrad, is there a > > bugzilla or any kind of email problem description that we can include > > here as a reference? I think there's a lost interrupt with qlcnic, > > but I don't know the details or what the failure looks like to a user. > > It is pretty catastrophic. Here is the console log when I pass in > a PCI device (with MSI-X) to the guest:
Perfect, thanks! I put the log info in https://bugzilla.kernel.org/show_bug.cgi?id=64581 and put this in my pci/misc branch for v3.13. I added the following to the changelog: This fixes a Xen guest crash when passing a PCI device with MSI-X to the guest. See the bugzilla for more details. [bhelgaas: add bugzilla info] Reference: https://bugzilla.kernel.org/show_bug.cgi?id=64581 Let me know if this needs any tweaking. Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
