Re: [RFC PATCH v9 for 4.15 01/14] Restartable sequences system call
From: Greg KH
Date: Wed Oct 18 2017 - 02:22:26 EST
On Tue, Oct 17, 2017 at 04:19:41PM +0000, Ben Maurer wrote:
> Hey,
>
> > So far the restrictions I see for libraries using this symbol are:
> > - They should never be unloaded,
> > - They should never be loaded with dlopen RTLD_LOCAL flag.
>
> We talked a bit about this off-list but I wanted to state publicly
> that I think this model works well for our use case. Specifically,
>
> (1) It reduces complexity by focusing on the common case -- long term
> we expect glibc to manage the process of using this feature and
> registering/deregistering threads for rseq. Unloading isn't a
> challenge in these situations, so why add the complexity for it?
You never install a new version of glibc on a running system, and expect
everything to keep running successfully? Breaking that would not be
good...
thanks,
greg k-h