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Date: Fri, 26 Jul 2013 12:23:25 +1000
From: Anton Blanchard <anton@samba.org>
To: Michael Neuling <mikey@neuling.org>, Alan Modra <amodra@gmail.com>, Ryan
 Arnold <ryanarn@us.ibm.com>
Subject: SIGSTKSZ/MINSIGSTKSZ too small on 64bit
Message-ID: <20130726122325.10b900e4@kryten>
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Hi,

Alan has been looking at a glibc test fail. His analysis shows SEGVs
in signal handlers using sigaltstack, and that MINSIGSTKSZ and SIGSTKSZ
are too small.

We increased the size of rt_sigframe in commit 2b0a576d15e0
(powerpc: Add new transactional memory state to the signal context) but
didn't bump either SIGSTKSZ and MINSIGSTKSZ. We need to do that in both
the kernel and glibc, but I'm a bit worried we could have broken
existing applications that use sigaltstack.

Anton