* Chris Kennelly: > When glibc provides registration, is the anticipated use case that a > library would unregister and reregister each thread to "upgrade" it to > the most modern version of interface it knows about provided by the > kernel? Absolutely not, that is likely to break other consumers because an expected rseq area becomes dormant instead. > There, I could assume an all-or-nothing registration of the new > feature--limited only by kernel availability for thread > homogeneity--but inconsistencies across early adopter libraries would > mean each thread would have to examine its own TLS to determine if a > feature were available. Exactly. Certain uses of seccomp can also have this effect, presenting a non-homogeneous view.
