| From 541e886f7972cc647804dbb4909189e67987a945 Mon Sep 17 00:00:00 2001 |
| From: Wanpeng Li <wanpengli@tencent.com> |
| Date: Fri, 17 May 2019 16:49:50 +0800 |
| Subject: KVM: nVMX: Fix using __this_cpu_read() in preemptible context |
| MIME-Version: 1.0 |
| Content-Type: text/plain; charset=UTF-8 |
| Content-Transfer-Encoding: 8bit |
| |
| From: Wanpeng Li <wanpengli@tencent.com> |
| |
| commit 541e886f7972cc647804dbb4909189e67987a945 upstream. |
| |
| 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> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| arch/x86/kvm/vmx/nested.c | 4 ++-- |
| 1 file changed, 2 insertions(+), 2 deletions(-) |
| |
| --- a/arch/x86/kvm/vmx/nested.c |
| +++ b/arch/x86/kvm/vmx/nested.c |
| @@ -2792,14 +2792,13 @@ static int nested_vmx_check_vmentry_hw(s |
| : "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; |
| @@ -2811,6 +2810,7 @@ static int nested_vmx_check_vmentry_hw(s |
| 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 |
