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Date: Wed, 18 Oct 2017 08:22:26 +0200
From: Greg KH <gregkh@linuxfoundation.org>
To: Ben Maurer <bmaurer@fb.com>
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Subject: Re: [RFC PATCH v9 for 4.15 01/14] Restartable sequences system call
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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