@@ -388,6 +388,19 @@ run::
160 1 0
135 1 0
+Behaviour can be tweaked with the following arguments:
+
+.. list-table:: Syscall plugin arguments
+ :widths: 20 80
+ :header-rows: 1
+
+ * - Option
+ - Description
+ * - print=true|false
+ - Print the number of times each syscall is called
+ * - log_writes=true|false
+ - Log the buffer of each write syscall in hexdump format
+
Test inline operations
......................
@@ -777,4 +790,3 @@ Other emulation features
When running system emulation you can also enable deterministic
execution which allows for repeatable record/replay debugging. See
:ref:`Record/Replay<replay>` for more details.
-
@@ -22,8 +22,57 @@ typedef struct {
int64_t errors;
} SyscallStats;
+struct SyscallInfo {
+ const char *name;
+ int64_t write_sysno;
+};
+
+const struct SyscallInfo arch_syscall_info[] = {
+ { "aarch64", 64 },
+ { "aarch64_be", 64 },
+ { "alpha", 4 },
+ { "arm", 4 },
+ { "armeb", 4 },
+ { "avr", -1 },
+ { "cris", -1 },
+ { "hexagon", 64 },
+ { "hppa", -1 },
+ { "i386", 4 },
+ { "loongarch64", -1 },
+ { "m68k", 4 },
+ { "microblaze", 4 },
+ { "microblazeel", 4 },
+ { "mips", 1 },
+ { "mips64", 1 },
+ { "mips64el", 1 },
+ { "mipsel", 1 },
+ { "mipsn32", 1 },
+ { "mipsn32el", 1 },
+ { "or1k", -1 },
+ { "ppc", 4 },
+ { "ppc64", 4 },
+ { "ppc64le", 4 },
+ { "riscv32", 64 },
+ { "riscv64", 64 },
+ { "rx", -1 },
+ { "s390x", -1 },
+ { "sh4", -1 },
+ { "sh4eb", -1 },
+ { "sparc", 4 },
+ { "sparc32plus", 4 },
+ { "sparc64", 4 },
+ { "tricore", -1 },
+ { "x86_64", 1 },
+ { "xtensa", 13 },
+ { "xtensaeb", 13 },
+ { NULL, -1 },
+};
+
static GMutex lock;
static GHashTable *statistics;
+static GByteArray *memory_buffer;
+static bool do_log_writes;
+static int64_t write_sysno = -1;
static SyscallStats *get_or_create_entry(int64_t num)
{
@@ -39,6 +88,44 @@ static SyscallStats *get_or_create_entry(int64_t num)
return entry;
}
+/*
+ * Hex-dump a GByteArray to the QEMU plugin output in the format:
+ * 61 63 63 65 6c 09 09 20 20 20 66 70 75 09 09 09 | accel.....fpu...
+ * 20 6d 6f 64 75 6c 65 2d 63 6f 6d 6d 6f 6e 2e 63 | .module-common.c
+ */
+static void hexdump(const GByteArray *data)
+{
+ g_autoptr(GString) out = g_string_new("");
+
+ for (guint index = 0; index < data->len; index += 16) {
+ for (guint col = 0; col < 16; col++) {
+ if (index + col < data->len) {
+ g_string_append_printf(out, "%02x ", data->data[index + col]);
+ } else {
+ g_string_append(out, " ");
+ }
+ }
+
+ g_string_append(out, " | ");
+
+ for (guint col = 0; col < 16; col++) {
+ if (index + col >= data->len) {
+ break;
+ }
+
+ if (g_ascii_isgraph(data->data[index + col])) {
+ g_string_append_printf(out, "%c", data->data[index + col]);
+ } else {
+ g_string_append(out, ".");
+ }
+ }
+
+ g_string_append(out, "\n");
+ }
+
+ qemu_plugin_outs(out->str);
+}
+
static void vcpu_syscall(qemu_plugin_id_t id, unsigned int vcpu_index,
int64_t num, uint64_t a1, uint64_t a2,
uint64_t a3, uint64_t a4, uint64_t a5,
@@ -54,6 +141,14 @@ static void vcpu_syscall(qemu_plugin_id_t id, unsigned int vcpu_index,
g_autofree gchar *out = g_strdup_printf("syscall #%" PRIi64 "\n", num);
qemu_plugin_outs(out);
}
+
+ if (do_log_writes && num == write_sysno) {
+ if (qemu_plugin_read_memory_vaddr(a2, memory_buffer, a3)) {
+ hexdump(memory_buffer);
+ } else {
+ fprintf(stderr, "Error reading memory from vaddr %lu\n", a2);
+ }
+ }
}
static void vcpu_syscall_ret(qemu_plugin_id_t id, unsigned int vcpu_idx,
@@ -127,6 +222,10 @@ QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id,
if (!qemu_plugin_bool_parse(tokens[0], tokens[1], &do_print)) {
fprintf(stderr, "boolean argument parsing failed: %s\n", opt);
}
+ } else if (g_strcmp0(tokens[0], "log_writes") == 0) {
+ if (!qemu_plugin_bool_parse(tokens[0], tokens[1], &do_log_writes)) {
+ fprintf(stderr, "boolean argument parsing failed: %s\n", opt);
+ }
} else {
fprintf(stderr, "unsupported argument: %s\n", argv[i]);
return -1;
@@ -137,6 +236,24 @@ QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id,
statistics = g_hash_table_new_full(NULL, g_direct_equal, NULL, g_free);
}
+ if (do_log_writes) {
+ for (const struct SyscallInfo *syscall_info = arch_syscall_info;
+ syscall_info->name != NULL; syscall_info++) {
+
+ if (g_strcmp0(syscall_info->name, info->target_name) == 0) {
+ write_sysno = syscall_info->write_sysno;
+ break;
+ }
+ }
+
+ if (write_sysno == -1) {
+ fprintf(stderr, "write syscall number not found\n");
+ return -1;
+ }
+
+ memory_buffer = g_byte_array_new();
+ }
+
qemu_plugin_register_vcpu_syscall_cb(id, vcpu_syscall);
qemu_plugin_register_vcpu_syscall_ret_cb(id, vcpu_syscall_ret);
qemu_plugin_register_atexit_cb(id, plugin_exit, NULL);