github.com/google/syzkaller@v0.0.0-20251211124644-a066d2bc4b02/sys/linux/test/amd64-syz_kvm_setup_syzos_vm-wr_drn-soft (about)

     1  #
     2  # requires: arch=amd64 -threaded
     3  #
     4  r0 = openat$kvm(0, &AUTO='/dev/kvm\x00', 0x0, 0x0)
     5  r1 = ioctl$KVM_CREATE_VM(r0, AUTO, 0x0)
     6  r2 = syz_kvm_setup_syzos_vm$x86(r1, &(0x7f0000c00000/0x400000)=nil)
     7  
     8  # DR7.GD=1 causes further attempts to touch a debug register to result in a debug exception.
     9  #
    10  r3 = syz_kvm_add_vcpu$x86(r2, &AUTO={0x0, &AUTO=[@wr_drn={AUTO, AUTO, {0x7, 0x2000}}, @wr_drn={AUTO, AUTO, {0x0, 0x1}}], AUTO})
    11  
    12  # 0x10001 = KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP enables software breakpoints.
    13  #
    14  ioctl$KVM_SET_GUEST_DEBUG_x86(r3, AUTO, &AUTO={0x10001, 0x0, {[0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0]}})
    15  r4 = ioctl$KVM_GET_VCPU_MMAP_SIZE(r0, AUTO)
    16  r5 = mmap$KVM_VCPU(&(0x7f0000009000/0x1000)=nil, r4, 0x3, 0x1, r3, 0x0)
    17  
    18  ioctl$KVM_RUN(r3, AUTO, 0x0)
    19  
    20  # Ensure that the exception is handled by the guest, and the program finishes normally.
    21  #
    22  syz_kvm_assert_syzos_kvm_exit$x86(r5, 0x6)
    23  syz_kvm_assert_syzos_uexit$x86(r5, 0xffffffffffffffff)