baremetal: exit at the end of main instead of infinite loop

run: interpret lkmc_test_fail as the last line of test as an error

baremetal/arch/aarch64/floating_point.S

@@ -0,0 +1,25 @@
+/* https://github.com/cirosantilli/arm-assembly-cheat/blob/c19e187e98e99f2f4a042783ca238aa4eb2292ab/v8/floating_point.S */
+
+.global main
+main:
+    /* 1.5 + 2.5 == 4.0 */
+    fmov d0, #1.5
+    fmov d1, #2.5
+    fadd d2, d0, d1
+    fmov d3, #4.0
+    fcmp d2, d3
+    beq 1f
+    bl assert_fail
+1:
+
+    /* Now in 32-bit. */
+    fmov s0, #1.5
+    fmov s1, #2.5
+    fadd s2, s0, s1
+    fmov s3, #4.0
+    fcmp s2, s3
+    beq 1f
+    bl assert_fail
+1:
+
+    ret

baremetal/arch/aarch64/return.S

@@ -0,0 +1,4 @@
+/* Return to ensure that the post main works. */
+.global main
+main:
+    ret

baremetal/interactive/hello.c

@@ -0,0 +1,6 @@
+#include <stdio.h>
+
+void main(void) {
+	puts("hello");
+	return;
+}

baremetal/lib/aarch64.S

@@ -8,4 +8,5 @@ mystart:
     ldr x0, =stack_top
     mov sp, x0
     bl main
-    b .
+    mov x0, #0
+    bl exit

baremetal/lib/arm.S

@@ -2,4 +2,5 @@
 mystart:
     ldr sp, =stack_top
     bl main
-    b .
+    mov r0, #0
+    bl exit

baremetal/return.c

@@ -0,0 +1,3 @@
+void main(void) {
+	return;
+}

common.py

@@ -72,6 +72,7 @@ kernel_module_ext = '.ko'
 obj_ext = '.o'
 config_file = os.path.join(data_dir, 'config')
 command_prefix = '+ '
+magic_fail_string = b'lkmc_test_fail'
 if os.path.exists(config_file):
     config = imp.load_source('config', config_file)
     configs = {x:getattr(config, x) for x in dir(config) if not x.startswith('__')}
@@ -774,6 +775,7 @@ def setup(parser):
     this_module.m5out_dir = os.path.join(this_module.gem5_run_dir, 'm5out')
     this_module.stats_file = os.path.join(this_module.m5out_dir, 'stats.txt')
     this_module.trace_txt_file = os.path.join(this_module.m5out_dir, 'trace.txt')
+    this_module.gem5_guest_terminal_file = os.path.join(this_module.m5out_dir, 'system.terminal')
     this_module.gem5_readfile = os.path.join(this_module.gem5_run_dir, 'readfile')
     this_module.gem5_termout_file = os.path.join(this_module.gem5_run_dir, 'termout.txt')
     this_module.qemu_run_dir = os.path.join(this_module.run_dir_base, 'qemu', args.arch, str(args.run_id))
@@ -782,6 +784,7 @@ def setup(parser):
     this_module.qemu_trace_txt_file = os.path.join(this_module.qemu_run_dir, 'trace.txt')
     this_module.qemu_termout_file = os.path.join(this_module.qemu_run_dir, 'termout.txt')
     this_module.qemu_rrfile = os.path.join(this_module.qemu_run_dir, 'rrfile')
+    this_module.qemu_guest_terminal_file = os.path.join(this_module.m5out_dir, qemu_termout_file)
     this_module.gem5_out_dir = os.path.join(this_module.out_dir, 'gem5')
     if args.gem5_build_dir is None:
         this_module.gem5_build_dir = os.path.join(this_module.gem5_out_dir, args.gem5_build_id, args.gem5_build_type)
@@ -817,10 +820,12 @@ def setup(parser):
         this_module.executable = this_module.gem5_executable
         this_module.run_dir = this_module.gem5_run_dir
         this_module.termout_file = this_module.gem5_termout_file
+        this_module.guest_terminal_file = gem5_guest_terminal_file
     else:
         this_module.executable = this_module.qemu_executable
         this_module.run_dir = this_module.qemu_run_dir
         this_module.termout_file = this_module.qemu_termout_file
+        this_module.guest_terminal_file = qemu_guest_terminal_file
     this_module.gem5_config_dir = os.path.join(this_module.gem5_src_dir, 'configs')
     this_module.gem5_se_file = os.path.join(this_module.gem5_config_dir, 'example', 'se.py')
     this_module.gem5_fs_file = os.path.join(this_module.gem5_config_dir, 'example', 'fs.py')

run

@@ -392,11 +392,20 @@ def main(args, extra_args=None):
     else:
         panic_msg = b'Kernel panic - not syncing'
     panic_re = re.compile(panic_msg)
+    error_string_found = False
     with open(common.termout_file, 'br') as logfile:
         for line in logfile:
             if panic_re.search(line):
-                common.log_error('simulation error detected by parsing logs')
-                return 1
+                error_string_found = True
+    with open(common.guest_terminal_file, 'br') as logfile:
+        lines = logfile.readlines()
+        if lines:
+            last_line = lines[-1]
+            if last_line.rstrip() == common.magic_fail_string:
+                error_string_found = True
+    if error_string_found:
+        common.log_error('simulation error detected by parsing logs')
+        return 1
     return 0
 
 def get_argparse():