Description of problem: Try to boot a guest with pf/vf already used by another booted guest , kernel report: kernel: Uhhuh. NMI received for unknown reason 30. kernel: Do you have a strange power saving mode enabled? kernel: Dazed and confused, but trying to continue Kill this guest, every time boot a new guest with this pf/vf assigned, got: warning: at drivers/pci/msi.c:968 pci_enable_msi() kernel: Call Trace: kernel: [<ffffffff80171d7e>] pci_enable_msi+0x7e/0x315 kernel: [<ffffffff8831f842>] :kvm:kvm_free_irq+0x24/0x40 kernel: [<ffffffff8830910f>] :kvm:kvm_vm_ioctl+0x75e/0xc39 kernel: [<ffffffff8830c066>] :kvm:emulator_write_emulated_onepage+0xac/0xf9 kernel: [<ffffffff8831a333>] :kvm:x86_emulate_insn+0x3c05/0x4c89 kernel: [<ffffffff8007a7a0>] ack_edge_ioapic_vector+0x40/0x42 kernel: [<ffffffff8831bccb>] :kvm:x86_decode_insn+0x914/0xb19 kernel: [<ffffffff8006ed34>] do_gettimeofday+0x40/0x90 kernel: [<ffffffff8830721e>] :kvm:kvm_io_bus_find_dev+0x35/0x52 kernel: [<ffffffff8022ebba>] pci_conf1_read+0xcc/0xd7 kernel: [<ffffffff8016009e>] pci_user_read_config_byte+0x51/0x6d kernel: [<ffffffff80042482>] do_ioctl+0x21/0x6b kernel: [<ffffffff800304ca>] vfs_ioctl+0x457/0x4b9 kernel: [<ffffffff800bad7a>] audit_syscall_entry+0x1a8/0x1d3 kernel: [<ffffffff8004c884>] sys_ioctl+0x59/0x78 kernel: [<ffffffff8005d29e>] tracesys+0xd5/0xdf Version-Release number of selected component (if applicable): host: kernel-2.6.18-339.el5 kvm-83-262.el5 guest: kernel-2.6.18-339.el5 How reproducible: always Steps to Reproduce: 1.modprobe -r ixgbe; modprobe ixgbe max_vfs=7, unbind 1 pf and 1 vf; 2.boot a guest with the pf/vf; 3.try to boot another guest with the same pf/vf, then the task failed cli: # /usr/libexec/qemu-kvm -m 3072 -smp 4 -startdate now -name mig -k en-us -drive file=/mnt/nfs/rhel590910r2.qcow2,if=ide,format=qcow2,werror=stop,boot=on,media=disk -spice ic=on,disable-ticketing,port=9010 -qxl 1 -M rhel5.6.0 -balloon none -monitor stdio -pcidevice host=06:00.0 failure: Failed to assign device "06:00.0" : Device or resource busy Failed to deassign device "06:00.0" : Invalid argument Failed to initialize assigned device host=06:00.0 4. quit all the qemu processes, then boot a guest with the same pf/vf Actual results: for step 3, after the failure, the host's log: kernel: Uhhuh. NMI received for unknown reason 30. kernel: Do you have a strange power saving mode enabled? kernel: Dazed and confused, but trying to continue kernel: Uhhuh. NMI received for unknown reason 03. kernel: Do you have a strange power saving mode enabled? Sep 21 16:38:13 virtlab-66-84-72 kernel: Dazed and confused, but trying to continue after step 4, the host had warning: warning: at drivers/pci/msi.c:968 pci_enable_msi() kernel: Call Trace: kernel: [<ffffffff80171d7e>] pci_enable_msi+0x7e/0x315 kernel: [<ffffffff8831f842>] :kvm:kvm_free_irq+0x24/0x40 kernel: [<ffffffff8830910f>] :kvm:kvm_vm_ioctl+0x75e/0xc39 kernel: [<ffffffff8830c066>] :kvm:emulator_write_emulated_onepage+0xac/0xf9 kernel: [<ffffffff8831a333>] :kvm:x86_emulate_insn+0x3c05/0x4c89 kernel: [<ffffffff8007a7a0>] ack_edge_ioapic_vector+0x40/0x42 kernel: [<ffffffff8831bccb>] :kvm:x86_decode_insn+0x914/0xb19 kernel: [<ffffffff8006ed34>] do_gettimeofday+0x40/0x90 kernel: [<ffffffff8830721e>] :kvm:kvm_io_bus_find_dev+0x35/0x52 kernel: [<ffffffff8022ebba>] pci_conf1_read+0xcc/0xd7 kernel: [<ffffffff8016009e>] pci_user_read_config_byte+0x51/0x6d kernel: [<ffffffff80042482>] do_ioctl+0x21/0x6b kernel: [<ffffffff800304ca>] vfs_ioctl+0x457/0x4b9 kernel: [<ffffffff800bad7a>] audit_syscall_entry+0x1a8/0x1d3 kernel: [<ffffffff8004c884>] sys_ioctl+0x59/0x78 kernel: [<ffffffff8005d29e>] tracesys+0xd5/0xdf Expected results: "Uhhuh. NMI received for unknown reason 30" should not happen; and no such warning Additional info:
*** This bug has been marked as a duplicate of bug 851943 ***