Date: Wed, 12 Feb 2014 11:39:28 +0000
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Dave Chinner <david@fromorbit.com>, Dave Jones <davej@redhat.com>,
        Eric Sandeen <sandeen@sandeen.net>,
        Linux Kernel <linux-kernel@vger.kernel.org>, xfs@oss.sgi.com
Subject: Re: 3.14-rc2 XFS backtrace because irqs_disabled.
Message-ID: <20140212113928.GO18016@ZenIV.linux.org.uk>
References: <20140211172707.GA1749@redhat.com>
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 <20140212004403.GA17129@redhat.com>
 <20140212010941.GM18016@ZenIV.linux.org.uk>
 <CA+55aFwoWT-0A_KTkXMkNqOy8hc=YmouTMBgWUD_z+8qYPphjA@mail.gmail.com>
 <20140212040358.GA25327@redhat.com>
 <20140212042215.GN18016@ZenIV.linux.org.uk>
 <20140212054043.GB13997@dastard>
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On Tue, Feb 11, 2014 at 10:28:12PM -0800, Linus Torvalds wrote:

> It looks like just "do_signal()" has a stack frame that is about 230
> bytes even under normal circumstancs (largely due to "struct ksignal"
> - which in turn is largely due to the insane 128-byte padding in
> siginfo_t). Add a few other frames in there, and I guess that if it
> was close before, the coredump path just makes it go off.

We could, in principle, put it into task_struct and make get_signal()
return its address - do_signal() is called only in the code that does
assorted returns to userland...
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