For v7m we need to catch attempts to execute from special
addresses at 0xfffffff0 and above. Previously we did this
with the aid of a hacky special purpose lump of memory
in the address space and a check in translate.c for whether
we were translating code at those addresses.
We can implement this more cleanly using a CPU
unassigned access handler which throws the exception
if the unassigned access is for one of the special addresses.
Signed-off-by: Michael Davidsaver <mdavidsaver@gmail.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1484937883-1068-3-git-send-email-peter.maydell@linaro.org
[PMM:
* drop the deletion of the "don't interrupt if PC is magic"
code in arm_v7m_cpu_exec_interrupt() -- this is still
required
* don't generate an exception for unassigned accesses
which aren't to the magic address -- although doing
this is in theory correct in practice it will break
currently working guests which rely on the RAZ/WI
behaviour when they touch devices which we haven't
modelled.
* trigger EXCP_EXCEPTION_EXIT on is_exec, not !is_write
]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
542b3478a0