[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] AW: [Xen-users] Xen, IRQ-sharing and PCI passthrough
Florian, I read already here and there that you shall not use shared interrupts in different PV DomUs, although I never found a written statement. But behaviour is exactly as you described, thus I took care that cards that share an IRQ are in the same DomU/Dom0. I also selected my motherboards accordingly. When I lately discussed lately with someone about MSI, I had the hope this could help, because in my system, one PCI slot shares IRQ with the PCIe x1 slots, so by enabling MSI for the PCIe slots, I was hoping to make the PCI slot usable to put it in some DomU. I never managed to try it out, though. I was able to enable MSI, but currently I have an old VGA card in the slot, the replacement would be an PCIe VGA that wants too much power. Anyhow, to proof the theory, please post dmesg | grep GSI, lspci, and cat /proc/interrupts of Dom0 and the used DomUs. But I think you can see on your own. Some explanation is also here (in German): http://www.neobiker.de/wiki/index.php?title=XEN-PCI BR, Carsten. ----- Originalnachricht ----- Von: Florian Wagner <f_wagner@xxxxxxxxxx> Gesendet: Fre, 26.6.2009 11:15 An: xen-users@xxxxxxxxxxxxxxxxxxx Betreff: [Xen-users] Xen, IRQ-sharing and PCI passthrough Hello, I'm seeing problems with Xen and IRQ-sharing PCI cards which are passed through to a Xen DomU. As I'm not sure whether this is a problem with Xen or with the Debian Xen Kernel (2.6.26-13 from lenny) I'm using, I'd like to ask here before posting a bug. Reproducing the problem goes as follows: 1. Put a PCI card in the machine and make sure it shares it's IRQ with another one. In my case it is a RIO Specialix card but I doubt this makes any difference. 2. Map the card to a domU and use it there. In the RIO case this requires loading a kernel module and running a "rioboot" tool. 3. Power down (either shutdown or destroy) the domU without stopping the card (here: "riostop" and "rmmod rio"). The resulting kernel stack trace is as follows: [ 337.409057] pciback 0000:04:06.0: enabling device (0000 -> 0003) [ 337.480998] ACPI: PCI Interrupt 0000:04:06.0[A] -> Link [LNEA] -> GSI 19 (level, low) -> IRQ 19 [ 361.759041] eth0: port 2(vif2.0) entering disabled state [ 361.845321] eth0: port 2(vif2.0) entering disabled state [ 362.462574] ACPI: PCI interrupt for device 0000:04:06.0 disabled [ 363.769836] irq 19: nobody cared (try booting with the "irqpoll" option) [ 363.817174] Pid: 0, comm: swapper Not tainted 2.6.26-1-xen-amd64 #1 [ 363.817174] [ 363.817174] Call Trace: [ 363.817174] <IRQ> [<ffffffff8037c9b0>] irq_ignore_unhandled+0x1c/0x32 [ 364.024802] [<ffffffff8025f9ab>] __report_bad_irq+0x30/0x72 [ 364.024802] [<ffffffff8025fc74>] note_interrupt+0x287/0x2c7 [ 364.024802] [<ffffffff8026055c>] handle_level_irq+0xc3/0x118 [ 364.024802] [<ffffffff8020e13e>] do_IRQ+0x4e/0x9a [ 364.024802] [<ffffffff8037d6c4>] evtchn_do_upcall+0x13c/0x1fc [ 364.024802] [<ffffffff8020bbde>] do_hypervisor_callback+0x1e/0x30 [ 364.024802] <EOI> [<ffffffff8037c992>] force_evtchn_callback+0xa/0xb [ 364.024802] [<ffffffff8020e795>] xen_safe_halt+0x90/0xa6 [ 364.024802] [<ffffffff8020a0c8>] xen_idle+0x2e/0x66 [ 364.024802] [<ffffffff80209cd6>] cpu_idle+0x97/0xb9 [ 364.024802] [ 364.024802] handlers: [ 364.024802] [<ffffffffa00b42ad>] (megasas_isr+0x0/0x45 [megaraid_sas]) [ 364.024802] Disabling IRQ #19 My take on this: Xen (or rather the dom0 kernel?) disables the shared IRQ, which at that time is still in use by the other card. In my case this crashes the machine, since the IRQ is shared with the RAID controller. So: Is it a kernel or a hypervisor bug? And should it be reported to the Xen or the Debian maintainers? Regards Florian ------------------------------------------ Florian Wagner Abteilung EDV Telefon: 0821 / 4201 - 453 Fax: 0821 / 4201 - 411 E-Mail: f_wagner@xxxxxxxxxx Syscomp Biochemische Dienstleistungen GmbH August-Wessels-Straße 5, 86154 Augsburg Postfach 102506, 86015 Augsburg Telefon: 0821 / 4201 - 0 Fax: 0821 / 417992 Web: http://www.syscomp.de E-Mail: syscomp@xxxxxxxxxx Geschäftsführer: Dr. med. Bernd Schottdorf Gabriele Schottdorf Registergericht Augsburg HRB 8670 _______________________________________________ Xen-users mailing list Xen-users@xxxxxxxxxxxxxxxxxxx http://lists.xensource.com/xen-users _______________________________________________ Xen-users mailing list Xen-users@xxxxxxxxxxxxxxxxxxx http://lists.xensource.com/xen-users
|
Lists.xenproject.org is hosted with RackSpace, monitoring our |