This patchset adds the stubs necessary to support GDB memory tagging
commands on QEMU aarch64 user mode.
These new stubs handle the qIsAddressTagged, qMemTag, and QMemTag
packets, which allow GDB memory tagging subcommands 'check',
'print-allocation-tag', and 'set-allocation-tag' to work. The remaining
memory tagging commands ('print-logical-tag' and 'with-logical-tag')
will also work, but they don't rely on any stub because they perform
local operations.
Since the memory tagging stubs are not common to all architectures, this
patchset also introduces three functions: gdb_extend_qsupported_features,
gdb_extend_query_table, and gdb_extend_set_table. These functions can be
used to extend the target-specific 'qSupported' feature string and the
handlers for the 'q' (query) and 'Q' (set) packets. These new functions
are used to add the MTE stubs for the aarch64 gdbstub.
Note that this patchset requires a GDB that supports the
qIsAddressTagged packet (recently added to GDB), so the gdbstub MTE
tests introduced by it must be run using GDB's master branch, since the
GDB in the distros hasn't picked up the change yet.
Once GDB is built and installed locally, the tests can be exercised, for
example, this way:
make GDB=~/.local/bin/gdb run-tcg-tests-aarch64-linux-user -j 32