0c28712f51
The NS field in PTEs descriptors is tagging Secure/Non-secure physical
memory (pages). This field is relevant in Secure state only:
While in Secure state, software can access both the Secure and
Non-secure physical address spaces, software in Non-secure state can
only access Non-secure memory; the NS bit is hence discarded/treated as
1.
This patch is aligning VMSAv8-32 with VMSAv8-64, which is tagging the
pointed memory as Non-secure in case of a Non-secure lookup.
The old behaviour was probably not leading to incorrect execution:
once a translation completes, the security flag in the memory request
is chcked against the security state of the cpu (and not only relying
on the NS bit in the TLB entry)
if (isSecure && !te->ns) {
req->setFlags(Request::SECURE);
}
so we were already forbidding secure accesses from non secure world
if NS = 0.
It is however misleading in the debug logs to see tlb entries with
NSTID = 1 and NS = 0.
Change-Id: I1f964069f88c33fb14362dd4101cb22538907226
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/32638
Reviewed-by: Richard Cooper <richard.cooper@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This is the gem5 simulator. The main website can be found at http://www.gem5.org A good starting point is http://www.gem5.org/about, and for more information about building the simulator and getting started please see http://www.gem5.org/documentation and http://www.gem5.org/documentation/learning_gem5/introduction. To build gem5, you will need the following software: g++ or clang, Python (gem5 links in the Python interpreter), SCons, SWIG, zlib, m4, and lastly protobuf if you want trace capture and playback support. Please see http://www.gem5.org/documentation/general_docs/building for more details concerning the minimum versions of the aforementioned tools. Once you have all dependencies resolved, type 'scons build/<ARCH>/gem5.opt' where ARCH is one of ARM, NULL, MIPS, POWER, SPARC, or X86. This will build an optimized version of the gem5 binary (gem5.opt) for the the specified architecture. See http://www.gem5.org/documentation/general_docs/building for more details and options. The basic source release includes these subdirectories: - configs: example simulation configuration scripts - ext: less-common external packages needed to build gem5 - src: source code of the gem5 simulator - system: source for some optional system software for simulated systems - tests: regression tests - util: useful utility programs and files To run full-system simulations, you will need compiled system firmware (console and PALcode for Alpha), kernel binaries and one or more disk images. If you have questions, please send mail to gem5-users@gem5.org Enjoy using gem5 and please share your modifications and extensions.