On 05/19/20 20:20, Philippe Mathieu-Daudé wrote:
> This is to silent:
>
> $ qemu-system-x86_64 \
> -object tls-cipher-suites,id=ciphersuite0,priority=@SYSTEM \
> -fw_cfg name=etc/edk2/https/ciphers,blob_id=ciphersuite0
> qemu-system-x86_64: -fw_cfg
> name=etc/edk2/https/ciphers,blob_id=ciphersuite0: warning: externally
> provided fw_cfg item names should be prefixed with "opt/"
>
> Signed-off-by: Philippe Mathieu-Daudé <phi...@redhat.com>
> ---
> softmmu/vl.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/softmmu/vl.c b/softmmu/vl.c
> index f76c53ad2e..3b77dcc00d 100644
> --- a/softmmu/vl.c
> +++ b/softmmu/vl.c
> @@ -2052,7 +2052,7 @@ static int parse_fw_cfg(void *opaque, QemuOpts *opts,
> Error **errp)
> FW_CFG_MAX_FILE_PATH - 1);
> return -1;
> }
> - if (strncmp(name, "opt/", 4) != 0) {
> + if (!nonempty_str(blob_id) && strncmp(name, "opt/", 4) != 0) {
> warn_report("externally provided fw_cfg item names "
> "should be prefixed with \"opt/\"");
> }
>
Hmmm, difficult question! Is "ciphersuite0" now externally provided or not?
Because, ciphersuite0 is populated internally to QEMU alright (and so we
can think it's internal), but its *association with the name* is external.
What if we keep the same "-object" switch, but use a different (bogus)
"name" with "-fw_cfg"? IMO that kind of invalidates "-object" too.
Should the fw_cfg generator interface dictate the fw_cfg filename too?
Because that would eliminate this problem. Put differently, we now have
a possibility to label the "ciphersuite0" object in the fw_cfg file
directory any way we want -- but is that freedom *useful* for anything?
I guess we might want multiple "tls-cipher-suites" objects one day, so
hard-coding the fw_cfg names on that level could cause conflicts. On the
other hand, I wouldn't like "blob_id" to generally circumvent the "etc/"
namespace protection.
I'm leaning towards agreeing with this patch, but I'd appreciate some
convincing arguments.
Thanks
Laszlo
