linux/virt/kvm
Wanpeng Li 571ee1b685 kvm: vfio: fix unregister kvm_device_ops of vfio
After commit 80ce163 (KVM: VFIO: register kvm_device_ops dynamically),
kvm_device_ops of vfio can be registered dynamically. Commit 3c3c29fd
(kvm-vfio: do not use module_init) move the dynamic register invoked by
kvm_init in order to fix broke unloading of the kvm module. However,
kvm_device_ops of vfio is unregistered after rmmod kvm-intel module
which lead to device type collision detection warning after kvm-intel
module reinsmod.

    WARNING: CPU: 1 PID: 10358 at /root/cathy/kvm/arch/x86/kvm/../../../virt/kvm/kvm_main.c:3289 kvm_init+0x234/0x282 [kvm]()
    Modules linked in: kvm_intel(O+) kvm(O) nfsv3 nfs_acl auth_rpcgss oid_registry nfsv4 dns_resolver nfs fscache lockd sunrpc pci_stub bridge stp llc autofs4 8021q cpufreq_ondemand ipv6 joydev microcode pcspkr igb i2c_algo_bit ehci_pci ehci_hcd e1000e i2c_i801 ixgbe ptp pps_core hwmon mdio tpm_tis tpm ipmi_si ipmi_msghandler acpi_cpufreq isci libsas scsi_transport_sas button dm_mirror dm_region_hash dm_log dm_mod [last unloaded: kvm_intel]
    CPU: 1 PID: 10358 Comm: insmod Tainted: G        W  O   3.17.0-rc1 #2
    Hardware name: Intel Corporation S2600CP/S2600CP, BIOS RMLSDP.86I.00.29.D696.1311111329 11/11/2013
     0000000000000cd9 ffff880ff08cfd18 ffffffff814a61d9 0000000000000cd9
     0000000000000000 ffff880ff08cfd58 ffffffff810417b7 ffff880ff08cfd48
     ffffffffa045bcac ffffffffa049c420 0000000000000040 00000000000000ff
    Call Trace:
     [<ffffffff814a61d9>] dump_stack+0x49/0x60
     [<ffffffff810417b7>] warn_slowpath_common+0x7c/0x96
     [<ffffffffa045bcac>] ? kvm_init+0x234/0x282 [kvm]
     [<ffffffff810417e6>] warn_slowpath_null+0x15/0x17
     [<ffffffffa045bcac>] kvm_init+0x234/0x282 [kvm]
     [<ffffffffa016e995>] vmx_init+0x1bf/0x42a [kvm_intel]
     [<ffffffffa016e7d6>] ? vmx_check_processor_compat+0x64/0x64 [kvm_intel]
     [<ffffffff810002ab>] do_one_initcall+0xe3/0x170
     [<ffffffff811168a9>] ? __vunmap+0xad/0xb8
     [<ffffffff8109c58f>] do_init_module+0x2b/0x174
     [<ffffffff8109d414>] load_module+0x43e/0x569
     [<ffffffff8109c6d8>] ? do_init_module+0x174/0x174
     [<ffffffff8109c75a>] ? copy_module_from_user+0x39/0x82
     [<ffffffff8109b7dd>] ? module_sect_show+0x20/0x20
     [<ffffffff8109d65f>] SyS_init_module+0x54/0x81
     [<ffffffff814a9a12>] system_call_fastpath+0x16/0x1b
    ---[ end trace 0626f4a3ddea56f3 ]---

The bug can be reproduced by:

    rmmod kvm_intel.ko
    insmod kvm_intel.ko

without rmmod/insmod kvm.ko
This patch fixes the bug by unregistering kvm_device_ops of vfio when the
kvm-intel module is removed.

Reported-by: Liu Rongrong <rongrongx.liu@intel.com>
Fixes: 3c3c29fd0d
Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-24 13:30:47 +02:00
..
arm arm/arm64: KVM: Fix BE accesses to GICv2 EISR and ELRSR regs 2014-10-16 10:57:41 +02:00
Kconfig KVM: Give IRQFD its own separate enabling Kconfig option 2014-08-05 14:26:28 +02:00
assigned-dev.c KVM: Use PCI device flag helper functions 2014-09-16 16:18:40 -06:00
async_pf.c kvm: Faults which trigger IO release the mmap_sem 2014-09-24 14:07:54 +02:00
async_pf.h
coalesced_mmio.c KVM: return an error code in kvm_vm_ioctl_register_coalesced_mmio() 2014-01-30 11:56:09 +01:00
coalesced_mmio.h
eventfd.c KVM: EVENTFD: Remove inclusion of irq.h 2014-09-24 12:06:25 +02:00
ioapic.c kvm: ioapic: conditionally delay irq delivery duringeoi broadcast 2014-09-16 14:44:48 +02:00
ioapic.h kvm: ioapic: conditionally delay irq delivery duringeoi broadcast 2014-09-16 14:44:48 +02:00
iodev.h
iommu.c kvm: fix excessive pages un-pinning in kvm_iommu_map error path. 2014-10-24 13:30:37 +02:00
irq_comm.c KVM: Move all accesses to kvm::irq_routing into irqchip.c 2014-08-05 14:26:20 +02:00
irqchip.c KVM: Move irq notifier implementation into eventfd.c 2014-08-05 14:26:24 +02:00
kvm_main.c kvm: vfio: fix unregister kvm_device_ops of vfio 2014-10-24 13:30:47 +02:00
vfio.c kvm: vfio: fix unregister kvm_device_ops of vfio 2014-10-24 13:30:47 +02:00
vfio.h kvm: vfio: fix unregister kvm_device_ops of vfio 2014-10-24 13:30:47 +02:00