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| author | Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> | 2011-01-12 15:39:18 +0800 |
|---|---|---|
| committer | Marcelo Tosatti <mtosatti@redhat.com> | 2011-03-17 13:08:26 -0300 |
| commit | 63f42e023ea270fde65fa27f0ca766e13faa5608 (patch) | |
| tree | 8cad1e7f55d9c8b6db2c7dc83153b90a79b4927f /arch/x86 | |
| parent | 40712faeb84dacfcb3925a88231daa08b3624d34 (diff) | |
| download | linux-stable-63f42e023ea270fde65fa27f0ca766e13faa5608.tar.gz linux-stable-63f42e023ea270fde65fa27f0ca766e13faa5608.tar.bz2 linux-stable-63f42e023ea270fde65fa27f0ca766e13faa5608.zip | |
KVM: fix rcu usage warning in kvm_arch_vcpu_ioctl_set_sregs()
Fix:
[ 1001.499596] ===================================================
[ 1001.499599] [ INFO: suspicious rcu_dereference_check() usage. ]
[ 1001.499601] ---------------------------------------------------
[ 1001.499604] include/linux/kvm_host.h:301 invoked rcu_dereference_check() without protection!
......
[ 1001.499636] Pid: 6035, comm: qemu-system-x86 Not tainted 2.6.37-rc6+ #62
[ 1001.499638] Call Trace:
[ 1001.499644] [] lockdep_rcu_dereference+0x9d/0xa5
[ 1001.499653] [] gfn_to_memslot+0x8d/0xc8 [kvm]
[ 1001.499661] [] gfn_to_hva+0x16/0x3f [kvm]
[ 1001.499669] [] kvm_read_guest_page+0x1e/0x5e [kvm]
[ 1001.499681] [] kvm_read_guest_page_mmu+0x53/0x5e [kvm]
[ 1001.499699] [] load_pdptrs+0x3f/0x9c [kvm]
[ 1001.499705] [] ? vmx_set_cr0+0x507/0x517 [kvm_intel]
[ 1001.499717] [] kvm_arch_vcpu_ioctl_set_sregs+0x1f3/0x3c0 [kvm]
[ 1001.499727] [] kvm_vcpu_ioctl+0x6a5/0xbc5 [kvm]
Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kvm/x86.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index bcc0efce85bf..4be89e1c0147 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5574,7 +5574,7 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs) { int mmu_reset_needed = 0; - int pending_vec, max_bits; + int pending_vec, max_bits, idx; struct desc_ptr dt; dt.size = sregs->idt.limit; @@ -5603,10 +5603,13 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu, kvm_x86_ops->set_cr4(vcpu, sregs->cr4); if (sregs->cr4 & X86_CR4_OSXSAVE) update_cpuid(vcpu); + + idx = srcu_read_lock(&vcpu->kvm->srcu); if (!is_long_mode(vcpu) && is_pae(vcpu)) { load_pdptrs(vcpu, vcpu->arch.walk_mmu, kvm_read_cr3(vcpu)); mmu_reset_needed = 1; } + srcu_read_unlock(&vcpu->kvm->srcu, idx); if (mmu_reset_needed) kvm_mmu_reset_context(vcpu); |