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Date: Thu, 16 Feb 2012 14:42:50 -0600
Message-ID: <CABqD9hZSLqn+=jr6sWwp_eJ5WsuGpH2Khoc_7aRmYt+1ZaEGoA@mail.gmail.com>
Subject: Re: [PATCH v8 5/8] seccomp: Add SECCOMP_RET_TRAP
From: Will Drewry <wad@chromium.org>
To: Markus Gutschke <markus@chromium.org>
Cc: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
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On Thu, Feb 16, 2012 at 2:24 PM, Markus Gutschke <markus@chromium.org> wrote:
> SIGTRAP might not be the ideal choice of signal number, as it can make it
> very difficult to debug the program in gdb.

True enough.  In theory, we could use the lower 16-bits of the return
value to let the bpf program set a signal, but not all signals are
masked synchronous and those that are probably get gdb's attention,
just not a severely :) (ILL, SEGV, BUS, TRAP, FPE). Perhaps SIGILL is
a logically appropriate option -- or letting the api user decide from
the SYNCHRONOUS_MASK set.  I'm open to whatever makes sense, though.
(I wasn't even sure if it was kosher to add a new TRAP_SECCOMP value.)

cheers!
will
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