Re: [PATCH trivial for-9.0] hw/i386/fw_cfg.c: fix non-legacy smbios build

[Philippe Mathieu-Daudé]

Hi Michael,

On 25/3/24 14:09, Michael Tokarev wrote:
> When building qemu with smbios but not legacy mode (eg minimal microvm build),
> link fails with:
>
>    hw/i386/fw_cfg.c:74: undefined reference to `smbios_get_table_legacy'
>
> This is because fw_cfg interface can call this function if CONFIG_SMBIOS
> is defined.  Made this code block to depend on CONFIG_SMBIOS_LEGACY.
>
> Fixes: b42b0e4daaa5 "smbios: build legacy mode code only for 'pc' machine"
> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
> ---
>   hw/i386/fw_cfg.c | 2 ++
>   1 file changed, 2 insertions(+)
>
> diff --git a/hw/i386/fw_cfg.c b/hw/i386/fw_cfg.c
> index d802d2787f..d5e78a9183 100644
> --- a/hw/i386/fw_cfg.c
> +++ b/hw/i386/fw_cfg.c
> @@ -70,6 +70,7 @@ void fw_cfg_build_smbios(PCMachineState *pcms, FWCfgState 
> *fw_cfg,
>       /* tell smbios about cpuid version and features */
>       smbios_set_cpuid(cpu->env.cpuid_version, cpu->env.features[FEAT_1_EDX]);
>   
> +#ifdef CONFIG_SMBIOS_LEGACY
>       if (pcmc->smbios_legacy_mode) {

But then having pcmc->smbios_legacy_mode == true without
CONFIG_SMBIOS_LEGACY would be a bug. IMHO what we want is:

-- >8 --
diff --git a/hw/smbios/smbios_legacy_stub.c b/hw/smbios/smbios_legacy_stub.c
index f29b15316c..7d593dca98 100644
--- a/hw/smbios/smbios_legacy_stub.c
+++ b/hw/smbios/smbios_legacy_stub.c
@@ -13,3 +13,8 @@
 void smbios_add_usr_blob_size(size_t size)
 {
 }
+
+uint8_t *smbios_get_table_legacy(size_t *length, Error **errp)
+{
+    g_assert_not_reached();
+}
---

>           smbios_tables = smbios_get_table_legacy(&smbios_tables_len,
>                                                   &error_fatal);
> @@ -77,6 +78,7 @@ void fw_cfg_build_smbios(PCMachineState *pcms, FWCfgState 
> *fw_cfg,
>                            smbios_tables, smbios_tables_len);
>           return;
>       }
> +#endif
>   
>       /* build the array of physical mem area from e820 table */
>       mem_array = g_malloc0(sizeof(*mem_array) * e820_get_num_entries());