• Suresh Siddha's avatar
    x86, xsave: save/restore the extended state context in sigframe · c37b5efe
    Suresh Siddha authored
    On cpu's supporting xsave/xrstor, fpstate pointer in the sigcontext, will
    include the extended state information along with fpstate information. Presence
    of extended state information is indicated by the presence
    of FP_XSTATE_MAGIC1 at fpstate.sw_reserved.magic1 and FP_XSTATE_MAGIC2
    at fpstate + (fpstate.sw_reserved.extended_size - FP_XSTATE_MAGIC2_SIZE).
    
    Extended feature bit mask that is saved in the memory layout is represented
    by the fpstate.sw_reserved.xstate_bv
    
    For RT signal frames, UC_FP_XSTATE in the uc_flags also indicate the
    presence of extended state information in the sigcontext's fpstate
    pointer.
    Signed-off-by: default avatarSuresh Siddha <suresh.b.siddha@intel.com>
    Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
    Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
    c37b5efe
i387.c 14.9 KB