Stas,You mean, if SS_AUTODISARM was previously used, right?
I have attempted to document the SS_AUTODISARM feature that you added
in Linux 4.7.
Could you please take a look at the SS_AUTODISARM pieces in the
sigaltstack() man page below? There is also one FIXME that I would
like help with.
It seems to me that the API has become rather odd now. It is no longer
possible to simply check whether code is executing on an alternative
stack by using
sigaltstack(NULL, &old_ss);
if (old_ss.ss_flags & SS_ONSTACK)
ss.ss_flagsIs this correct?
This field contains either 0, or the following flag:
âââââââââââââââââââââââââââââââââââââââââââââââââââââââMy memory may be wrong here, but I think setting
âFIXME â
âââââââââââââââââââââââââââââââââââââââââââââââââââââââ
âWas it intended that one can set up a different â
âalternative signal stack in this scenario? (In passâ â
âing, if one does this, the sigaltstack(NULL, â
â&old_ss) now returns old_ss.ss_flags==SS_AUTODISARM â
ârather than old_ss.ss_flags==SS_DISABLE. The API â
âdesign here seems confusing... â
âââââââââââââââââââââââââââââââââââââââââââââââââââââââ
SS_AUTODISARMInitially this flag was supposed to be ORed with
The alternate signal stack has been marked to be
autodisarmed as described above.