On 24/04/2019 03.16, Li Qiang wrote: > > Thomas Huth <th...@redhat.com <mailto:th...@redhat.com>> 于2019年4月24日 > 周三 上午12:29写道: > > On 20/04/2019 12.00, Li Qiang wrote: > > Signed-off-by: Li Qiang <liq...@163.com <mailto:liq...@163.com>> > > --- > > tests/fw_cfg-test.c | 19 +++++++++++++++++++ > > 1 file changed, 19 insertions(+) > > > > diff --git a/tests/fw_cfg-test.c b/tests/fw_cfg-test.c > > index c22503619f..9f75dbb5f4 100644 > > --- a/tests/fw_cfg-test.c > > +++ b/tests/fw_cfg-test.c > > @@ -174,6 +174,24 @@ static void test_fw_cfg_boot_menu(void) > > qtest_quit(s); > > } > > > > +static void test_fw_cfg_reboot_timeout(void) > > +{ > > + QFWCFG *fw_cfg; > > + QTestState *s; > > + uint32_t reboot_timeout = 0; > > + size_t filesize; > > + > > + s = qtest_init("-boot reboot-timeout=15"); > > + fw_cfg = pc_fw_cfg_init(s); > > + > > + filesize = qfw_cfg_get_file(fw_cfg, "etc/boot-fail-wait", > > + &reboot_timeout, sizeof(reboot_timeout)); > > + g_assert_cmpint(filesize, ==, sizeof(reboot_timeout)); > > + g_assert_cmpint(reboot_timeout, ==, 15); > > Is this endianess-safe? Or do you need to byteswap reboot_timeout if the > host and guest endianess does not match? > > Good question! > > IIUC, the qemu fw_cfg store the 'file' entry data just in byte stream. > So there is no need > to consider the file's endianess. If when the file entry is stored > without considering endianess, > it will be ok to ignore the endianess. So for this patch, the > 'reboot_timeout' is ok as when we stored > it we don't consider endianess. But for 'splash-time', when we stored > it we convert it to little endian > so when we fetches it, we should also convert it from little endian to > cpu-endian.
I just gave these patches a try on a big endian host, and the test fails indeed: $ QTEST_QEMU_BINARY=x86_64-softmmu/qemu-system-x86_64 tests/fw_cfg-test /x86_64/fw_cfg/signature: OK /x86_64/fw_cfg/id: OK /x86_64/fw_cfg/uuid: OK /x86_64/fw_cfg/ram_size: OK /x86_64/fw_cfg/nographic: OK /x86_64/fw_cfg/nb_cpus: OK /x86_64/fw_cfg/max_cpus: OK /x86_64/fw_cfg/numa: OK /x86_64/fw_cfg/boot_menu: OK /x86_64/fw_cfg/reboot_timeout: ** ERROR:tests/fw_cfg-test.c:190:test_fw_cfg_reboot_timeout: assertion failed (reboot_timeout == 15): (0 == 15) Aborted => it also fails for reboot_timeout already, not only for splash_time. > So I think we can have following choose: > > 1. Don't consider the endianess, this is ok when emaulated target and > host target has the same endianess. Sorry, but that's not a real choice. qtests must also work when you e.g. run qemu-system-x86_64 on a big endian host. Thomas