Re: Regarding https://sourceware.org/bugzilla/show_bug.cgi?id=22850

[Carlos O'Donell <carlos at redhat dot com>]

On 10/21/19 5:34 AM, kamlesh kumar wrote:
> I'm looking at the subjected issue and to start with we are thinking
> to move out the tcb from the thread stack

That sounds great.

> but we are not sure about like  where we can room this tcb structure
> (since we are new to libc ) and we would like to know your suggestion
> on this and did  anyone tried this implementation and would like to
> know cons and pros of this  implementation and etc .

As new contributors please review the "Contribution Checklist":
https://sourceware.org/glibc/wiki/Contribution%20checklist

Bug 22850 is a difficult bug that covers multiple subsystems and will
touch all architectures. It requires considerable skill to get all the
details right.

So far there is no attempted implementation in glibc where the TCB
and associated data is split from the thread stack.

A related bug is:
"Program with large TLS segments fail."
https://sourceware.org/bugzilla/show_bug.cgi?id=11787

Removing the struct pthread, the TCB, and TLS data from the stack
would make the stack extent computation much easier.

Someone needs to design a solution and present it to the community
with their evalution of the pros/cons of such a design.

-- 
Cheers,
Carlos.