diff options
| author | Lai Jiangshan | 2010-04-19 17:41:23 +0800 |
|---|---|---|
| committer | Avi Kivity | 2010-05-17 12:18:01 +0300 |
| commit | 90d83dc3d49f5101addae962ccc1b4aff66b68d8 (patch) | |
| tree | 855aec81663eff4597ab276f13d449be9b798ec2 /include/linux/kvm_host.h | |
| parent | 9beeaa2d689842f7760aa16c512e6bb8182d38b6 (diff) | |
KVM: use the correct RCU API for PROVE_RCU=y
The RCU/SRCU API have already changed for proving RCU usage.
I got the following dmesg when PROVE_RCU=y because we used incorrect API.
This patch coverts rcu_deference() to srcu_dereference() or family API.
===================================================
[ INFO: suspicious rcu_dereference_check() usage. ]
---------------------------------------------------
arch/x86/kvm/mmu.c:3020 invoked rcu_dereference_check() without protection!
other info that might help us debug this:
rcu_scheduler_active = 1, debug_locks = 0
2 locks held by qemu-system-x86/8550:
#0: (&kvm->slots_lock){+.+.+.}, at: [<ffffffffa011a6ac>] kvm_set_memory_region+0x29/0x50 [kvm]
#1: (&(&kvm->mmu_lock)->rlock){+.+...}, at: [<ffffffffa012262d>] kvm_arch_commit_memory_region+0xa6/0xe2 [kvm]
stack backtrace:
Pid: 8550, comm: qemu-system-x86 Not tainted 2.6.34-rc4-tip-01028-g939eab1 #27
Call Trace:
[<ffffffff8106c59e>] lockdep_rcu_dereference+0xaa/0xb3
[<ffffffffa012f6c1>] kvm_mmu_calculate_mmu_pages+0x44/0x7d [kvm]
[<ffffffffa012263e>] kvm_arch_commit_memory_region+0xb7/0xe2 [kvm]
[<ffffffffa011a5d7>] __kvm_set_memory_region+0x636/0x6e2 [kvm]
[<ffffffffa011a6ba>] kvm_set_memory_region+0x37/0x50 [kvm]
[<ffffffffa015e956>] vmx_set_tss_addr+0x46/0x5a [kvm_intel]
[<ffffffffa0126592>] kvm_arch_vm_ioctl+0x17a/0xcf8 [kvm]
[<ffffffff810a8692>] ? unlock_page+0x27/0x2c
[<ffffffff810bf879>] ? __do_fault+0x3a9/0x3e1
[<ffffffffa011b12f>] kvm_vm_ioctl+0x364/0x38d [kvm]
[<ffffffff81060cfa>] ? up_read+0x23/0x3d
[<ffffffff810f3587>] vfs_ioctl+0x32/0xa6
[<ffffffff810f3b19>] do_vfs_ioctl+0x495/0x4db
[<ffffffff810e6b2f>] ? fget_light+0xc2/0x241
[<ffffffff810e416c>] ? do_sys_open+0x104/0x116
[<ffffffff81382d6d>] ? retint_swapgs+0xe/0x13
[<ffffffff810f3ba6>] sys_ioctl+0x47/0x6a
[<ffffffff810021db>] system_call_fastpath+0x16/0x1b
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Diffstat (limited to 'include/linux/kvm_host.h')
| -rw-r--r-- | include/linux/kvm_host.h | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 55830638aeb1..1ed030bad59e 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -250,6 +250,13 @@ void kvm_exit(void); void kvm_get_kvm(struct kvm *kvm); void kvm_put_kvm(struct kvm *kvm); +static inline struct kvm_memslots *kvm_memslots(struct kvm *kvm) +{ + return rcu_dereference_check(kvm->memslots, + srcu_read_lock_held(&kvm->srcu) + || lockdep_is_held(&kvm->slots_lock)); +} + #define HPA_MSB ((sizeof(hpa_t) * 8) - 1) #define HPA_ERR_MASK ((hpa_t)1 << HPA_MSB) static inline int is_error_hpa(hpa_t hpa) { return hpa >> HPA_MSB; } |