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from __future__ import print_function
#
# Test some of the system debug features with the multiarch memory
# test. It is a port of the original vmlinux focused test case but
# using the "memory" test instead.
#
# This is launched via tests/guest-debug/run-test.py
#
import gdb
import sys
from test_gdbstub import main, report
def check_step():
"Step an instruction, check it moved."
start_pc = gdb.parse_and_eval('$pc')
gdb.execute("si")
end_pc = gdb.parse_and_eval('$pc')
return not (start_pc == end_pc)
#
# Currently it's hard to create a hbreak with the pure python API and
# manually matching PC to symbol address is a bit flaky thanks to
# function prologues. However internally QEMU's gdbstub treats them
# the same as normal breakpoints so it will do for now.
#
def check_break(sym_name):
"Setup breakpoint, continue and check we stopped."
sym, ok = gdb.lookup_symbol(sym_name)
bp = gdb.Breakpoint(sym_name, gdb.BP_BREAKPOINT)
gdb.execute("c")
# hopefully we came back
end_pc = gdb.parse_and_eval('$pc')
report(bp.hit_count == 1,
"break @ %s (%s %d hits)" % (end_pc, sym.value(), bp.hit_count))
bp.delete()
def do_one_watch(sym, wtype, text):
wp = gdb.Breakpoint(sym, gdb.BP_WATCHPOINT, wtype)
gdb.execute("c")
report_str = "%s for %s" % (text, sym)
if wp.hit_count > 0:
report(True, report_str)
wp.delete()
else:
report(False, report_str)
def check_watches(sym_name):
"Watch a symbol for any access."
# Should hit for any read
do_one_watch(sym_name, gdb.WP_ACCESS, "awatch")
# Again should hit for reads
do_one_watch(sym_name, gdb.WP_READ, "rwatch")
# Finally when it is written
do_one_watch(sym_name, gdb.WP_WRITE, "watch")
def run_test():
"Run through the tests one by one"
print("Checking we can step the first few instructions")
step_ok = 0
for i in range(3):
if check_step():
step_ok += 1
report(step_ok == 3, "single step in boot code")
# If we get here we have missed some of the other breakpoints.
print("Setup catch-all for _exit")
cbp = gdb.Breakpoint("_exit", gdb.BP_BREAKPOINT)
check_break("main")
check_watches("test_data[128]")
report(cbp.hit_count == 0, "didn't reach backstop")
main(run_test)
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