diff options
| author | Wanpeng Li <wanpeng.li@linux.intel.com> | 2014-10-09 14:30:08 +0400 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2014-10-24 15:30:47 +0400 |
| commit | 571ee1b6859869a09ed718d390aac2b9414646a2 (patch) | |
| tree | b3e2e7d8ecd05091642e00fa24d616dc41733856 /virt | |
| parent | 1715d0dcb0d4231983f1580e265c748cd3371f55 (diff) | |
| download | linux-571ee1b6859869a09ed718d390aac2b9414646a2.tar.xz | |
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: 3c3c29fd0d7cddc32862c350d0700ce69953e3bd
Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'virt')
| -rw-r--r-- | virt/kvm/kvm_main.c | 7 | ||||
| -rw-r--r-- | virt/kvm/vfio.c | 5 | ||||
| -rw-r--r-- | virt/kvm/vfio.h | 4 |
3 files changed, 16 insertions, 0 deletions
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 384eaa7b02fa..25ffac9e947d 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2354,6 +2354,12 @@ int kvm_register_device_ops(struct kvm_device_ops *ops, u32 type) return 0; } +void kvm_unregister_device_ops(u32 type) +{ + if (kvm_device_ops_table[type] != NULL) + kvm_device_ops_table[type] = NULL; +} + static int kvm_ioctl_create_device(struct kvm *kvm, struct kvm_create_device *cd) { @@ -3328,5 +3334,6 @@ void kvm_exit(void) kvm_arch_exit(); kvm_irqfd_exit(); free_cpumask_var(cpus_hardware_enabled); + kvm_vfio_ops_exit(); } EXPORT_SYMBOL_GPL(kvm_exit); diff --git a/virt/kvm/vfio.c b/virt/kvm/vfio.c index 281e7cf2b8e5..620e37f741b8 100644 --- a/virt/kvm/vfio.c +++ b/virt/kvm/vfio.c @@ -283,3 +283,8 @@ int kvm_vfio_ops_init(void) { return kvm_register_device_ops(&kvm_vfio_ops, KVM_DEV_TYPE_VFIO); } + +void kvm_vfio_ops_exit(void) +{ + kvm_unregister_device_ops(KVM_DEV_TYPE_VFIO); +} diff --git a/virt/kvm/vfio.h b/virt/kvm/vfio.h index 92eac75d6b62..ab88c7dc0514 100644 --- a/virt/kvm/vfio.h +++ b/virt/kvm/vfio.h @@ -3,11 +3,15 @@ #ifdef CONFIG_KVM_VFIO int kvm_vfio_ops_init(void); +void kvm_vfio_ops_exit(void); #else static inline int kvm_vfio_ops_init(void) { return 0; } +static inline void kvm_vfio_ops_exit(void) +{ +} #endif #endif |