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authorWanpeng Li <wanpengli@tencent.com>2019-05-17 16:49:50 +0800
committerPaolo Bonzini <pbonzini@redhat.com>2019-05-24 21:27:08 +0200
commit541e886f7972cc647804dbb4909189e67987a945 (patch)
tree12643c41feec9bdf6e0fc33130bbd349eb4c8f9d
parentd30b214d1d0addb7b2c9c78178d1501cd39a01fb (diff)
KVM: nVMX: Fix using __this_cpu_read() in preemptible context
BUG: using __this_cpu_read() in preemptible [00000000] code: qemu-system-x86/4590 caller is nested_vmx_enter_non_root_mode+0xebd/0x1790 [kvm_intel] CPU: 4 PID: 4590 Comm: qemu-system-x86 Tainted: G OE 5.1.0-rc4+ #1 Call Trace: dump_stack+0x67/0x95 __this_cpu_preempt_check+0xd2/0xe0 nested_vmx_enter_non_root_mode+0xebd/0x1790 [kvm_intel] nested_vmx_run+0xda/0x2b0 [kvm_intel] handle_vmlaunch+0x13/0x20 [kvm_intel] vmx_handle_exit+0xbd/0x660 [kvm_intel] kvm_arch_vcpu_ioctl_run+0xa2c/0x1e50 [kvm] kvm_vcpu_ioctl+0x3ad/0x6d0 [kvm] do_vfs_ioctl+0xa5/0x6e0 ksys_ioctl+0x6d/0x80 __x64_sys_ioctl+0x1a/0x20 do_syscall_64+0x6f/0x6c0 entry_SYSCALL_64_after_hwframe+0x49/0xbe Accessing per-cpu variable should disable preemption, this patch extends the preemption disable region for __this_cpu_read(). Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Fixes: 52017608da33 ("KVM: nVMX: add option to perform early consistency checks via H/W") Cc: stable@vger.kernel.org Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
-rw-r--r--arch/x86/kvm/vmx/nested.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 6b450839c766..1032f068f0b9 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -2784,14 +2784,13 @@ static int nested_vmx_check_vmentry_hw(struct kvm_vcpu *vcpu)
: "cc", "memory"
);
- preempt_enable();
-
if (vmx->msr_autoload.host.nr)
vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, vmx->msr_autoload.host.nr);
if (vmx->msr_autoload.guest.nr)
vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, vmx->msr_autoload.guest.nr);
if (vm_fail) {
+ preempt_enable();
WARN_ON_ONCE(vmcs_read32(VM_INSTRUCTION_ERROR) !=
VMXERR_ENTRY_INVALID_CONTROL_FIELD);
return 1;
@@ -2803,6 +2802,7 @@ static int nested_vmx_check_vmentry_hw(struct kvm_vcpu *vcpu)
local_irq_enable();
if (hw_breakpoint_active())
set_debugreg(__this_cpu_read(cpu_dr7), 7);
+ preempt_enable();
/*
* A non-failing VMEntry means we somehow entered guest mode with