• Mukesh Rathor's avatar
    xen/pvh: Secondary VCPU bringup (non-bootup CPUs) · 5840c84b
    Mukesh Rathor authored
    The VCPU bringup protocol follows the PV with certain twists.
    From xen/include/public/arch-x86/xen.h:
    
    Also note that when calling DOMCTL_setvcpucontext and VCPU_initialise
    for HVM and PVH guests, not all information in this structure is updated:
    
     - For HVM guests, the structures read include: fpu_ctxt (if
     VGCT_I387_VALID is set), flags, user_regs, debugreg[*]
    
     - PVH guests are the same as HVM guests, but additionally use ctrlreg[3] to
     set cr3. All other fields not used should be set to 0.
    
    This is what we do. We piggyback on the 'xen_setup_gdt' - but modify
    a bit - we need to call 'load_percpu_segment' so that 'switch_to_new_gdt'
    can load per-cpu data-structures. It has no effect on the VCPU0.
    
    We also piggyback on the %rdi register to pass in the CPU number - so
    that when we bootup a new CPU, the cpu_bringup_and_idle will have
    passed as the first parameter the CPU number (via %rdi for 64-bit).
    Signed-off-by: default avatarMukesh Rathor <mukesh.rathor@oracle.com>
    Signed-off-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
    5840c84b
enlighten.c 43.5 KB