Re: [PATCHv4] arm: Preserve the user r/w register TPIDRURW on contextswitch and fork

From: André Hentschel
Date: Sat May 18 2013 - 11:02:45 EST

Am 08.05.2013 21:03, schrieb André Hentschel:
> From: =?UTF-8?q?Andr=C3=A9=20Hentschel?= <nerv@xxxxxxxxxxx>
> Since commit 6a1c53124aa1 the user writeable TLS register was zeroed to
> prevent it from being used as a covert channel between two tasks.
> There are more and more applications coming to WinRT, Wine could support them,
> but mostly they expect to have the thread environment block (TEB) in TPIDRURW.
> This patch preserves that register per thread instead of clearing it.
> Unlike the TPIDRURO, which is already switched, the TPIDRURW
> can be updated from userspace so needs careful treatment in the case that we
> modify TPIDRURW and call fork(). To avoid this we must always read
> TPIDRURW in copy_thread.
> Signed-off-by: André Hentschel <nerv@xxxxxxxxxxx>
> Signed-off-by: Will Deacon <will.deacon@xxxxxxx>
> Signed-off-by: Jonathan Austin <jonathan.austin@xxxxxxx>

I'm not yet very familiar with the development process here,
am i getting no feedback on v4 because of the mergewindow being closed?
Or is there another reason? Sry for being impatient.
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