-
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:
[] dump_stack+0x49/0x60
[] warn_slowpath_common+0x7c/0x96
[] ? kvm_init+0x234/0x282 [kvm]
[] warn_slowpath_null+0x15/0x17
[] kvm_init+0x234/0x282 [kvm]
[] vmx_init+0x1bf/0x42a [kvm_intel]
[] ? vmx_check_processor_compat+0x64/0x64 [kvm_intel]
[] do_one_initcall+0xe3/0x170
[] ? __vunmap+0xad/0xb8
[] do_init_module+0x2b/0x174
[] load_module+0x43e/0x569
[] ? do_init_module+0x174/0x174
[] ? copy_module_from_user+0x39/0x82
[] ? module_sect_show+0x20/0x20
[] SyS_init_module+0x54/0x81
[] system_call_fastpath+0x16/0x1b
---[ end trace 0626f4a3ddea56f3 ]---The bug can be reproduced by:
rmmod kvm_intel.ko
insmod kvm_intel.kowithout 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
Fixes: 3c3c29fd0d7cddc32862c350d0700ce69953e3bd
Signed-off-by: Wanpeng Li
Signed-off-by: Paolo Bonzini