Re: [Qemu-devel] [PATCH v2 4/4] i440fx-test: verify firmware under 4G and 1M, both -bios and -pflash

[Markus Armbruster]

Laszlo Ersek <address@hidden> writes:

> Check whether the firmware is not hidden by other memory regions.
>
> Qemu is started in paused mode: it shouldn't try to interpret generated
> garbage.
>
> Signed-off-by: Laszlo Ersek <address@hidden>
> ---
>  tests/i440fx-test.c | 81 
> +++++++++++++++++++++++++++++++++++++++++++++++++----
>  1 file changed, 75 insertions(+), 6 deletions(-)
>
> diff --git a/tests/i440fx-test.c b/tests/i440fx-test.c
> index 5506421..6de16e9 100644
> --- a/tests/i440fx-test.c
> +++ b/tests/i440fx-test.c
> @@ -35,6 +35,11 @@ typedef struct TestData
>      int num_cpus;
>  } TestData;
>  
> +typedef struct FirmwareTestFixture {
> +    /* decides whether we're testing -bios or -pflash */
> +    bool is_bios;
> +} FirmwareTestFixture;
> +
>  static QPCIBus *test_start_get_bus(const TestData *s)
>  {
>      char *cmdline;
> @@ -278,6 +283,7 @@ static void test_i440fx_pam(gconstpointer opaque)
>  }
>  
>  #define FW_SIZE ((size_t)65536)
> +#define ISA_BIOS_MAXSZ ((size_t)(128 * 1024))
>  
>  /* Create a temporary firmware blob, and return its absolute pathname as a
>   * dynamically allocated string.
> @@ -328,23 +334,86 @@ static char *create_firmware(void)
>      return ret == -1 ? NULL : pathname;
>  }
>  
> -int main(int argc, char **argv)
> +static void test_i440fx_firmware(FirmwareTestFixture *fixture,
> +                                 gconstpointer user_data)
>  {
> -    char *fw_pathname;
> -    TestData data;
> -    int ret;
> -
> -    g_test_init(&argc, &argv, NULL);
> +    char *fw_pathname, *cmdline;
> +    char unsigned *buf;

unsigned char *buf, please.

> +    size_t i, isa_bios_size;
>  
>      fw_pathname = create_firmware();
>      g_assert(fw_pathname != NULL);
> +
> +    /* Better hope the user didn't put metacharacters in TMPDIR and co. */

Putting meta-characters in TMPDIR would be... adventurous.

You could add quotes.  Then it breaks only when the user puts quotes in ;-P

> +    cmdline = g_strdup_printf("-S %s %s",
> +                              fixture->is_bios ? "-bios" : "-pflash",
> +                              fw_pathname);
> +    g_test_message("qemu cmdline: %s", cmdline);
> +    qtest_start(cmdline);
> +    g_free(cmdline);
> +
> +    /* Qemu has loaded the firmware (because qtest_start() only returns after
> +     * the QMP handshake completes). We must unlink the firmware blob right
> +     * here, because any assertion firing below would leak it in the
> +     * filesystem. This is also the reason why we recreate the blob every 
> time
> +     * this function is invoked.
> +     */
>      unlink(fw_pathname);
>      g_free(fw_pathname);
>  
> +    /* check below 4G */
> +    buf = g_malloc0(FW_SIZE);
> +    memread(0x100000000ULL - FW_SIZE, buf, FW_SIZE);

Zero-fill immediately followed by read.  Suggest g_malloc().

> +    for (i = 0; i < FW_SIZE; ++i) {
> +        g_assert_cmphex(buf[i], ==, (char unsigned)i);

(unsigned char), please.

> +    }
> +
> +    /* check in ISA space too */
> +    memset(buf, 0, FW_SIZE);
> +    isa_bios_size = ISA_BIOS_MAXSZ < FW_SIZE ? ISA_BIOS_MAXSZ : FW_SIZE;
> +    memread(0x100000 - isa_bios_size, buf, isa_bios_size);

Zero-fill immediately followed by read.  Suggest to drop memset().

> +    for (i = 0; i < isa_bios_size; ++i) {
> +        g_assert_cmphex(buf[i], ==,
> +                        (char unsigned)((FW_SIZE - isa_bios_size) + i));

Again.

> +    }
> +
> +    g_free(buf);
> +    qtest_end();
> +}
> +
> +static void add_firmware_test(const char *testpath,
> +                              void (*setup_fixture)(FirmwareTestFixture *f,
> +                                                    gconstpointer test_data))
> +{
> +    g_test_add(testpath, FirmwareTestFixture, NULL, setup_fixture,
> +               test_i440fx_firmware, NULL);
> +}
> +
> +static void request_bios(FirmwareTestFixture *fixture,
> +                         gconstpointer user_data)
> +{
> +    fixture->is_bios = true;
> +}
> +
> +static void request_pflash(FirmwareTestFixture *fixture,
> +                           gconstpointer user_data)
> +{
> +    fixture->is_bios = false;
> +}
> +

I'm not sure fixtures are justified here.  Perhaps having the test
function's test data argument point to the flag would be simpler.

> +int main(int argc, char **argv)
> +{
> +    TestData data;
> +    int ret;
> +
> +    g_test_init(&argc, &argv, NULL);
> +
>      data.num_cpus = 1;
>  
>      g_test_add_data_func("/i440fx/defaults", &data, test_i440fx_defaults);
>      g_test_add_data_func("/i440fx/pam", &data, test_i440fx_pam);
> +    add_firmware_test("/i440fx/firmware/bios", request_bios);
> +    add_firmware_test("/i440fx/firmware/pflash", request_pflash);
>  
>      ret = g_test_run();
>      return ret;