Re: [PATCH] fw_cfg: Allow reboot-timeout=-1 again

[Markus Armbruster]

"Dr. David Alan Gilbert" <address@hidden> writes:

> * Markus Armbruster (address@hidden) wrote:
>> "Dr. David Alan Gilbert (git)" <address@hidden> writes:
>> 
>> > From: "Dr. David Alan Gilbert" <address@hidden>
>> >
>> > Commit ee5d0f89de3e53cdb0dc added range checking on reboot-timeout
>> > to only allow the range 0..65535; however both qemu and libvirt document
>> > the special value -1  to mean don't reboot.
>> > Allow it again.
>> >
>> > Fixes: ee5d0f89de3e53cdb0dc ("fw_cfg: Fix -boot reboot-timeout error 
>> > checking")
>> > RH bz: https://bugzilla.redhat.com/show_bug.cgi?id=1765443
>> > Signed-off-by: Dr. David Alan Gilbert <address@hidden>
>> > ---
>> >  hw/nvram/fw_cfg.c | 5 +++--
>> >  1 file changed, 3 insertions(+), 2 deletions(-)
>> >
>> > diff --git a/hw/nvram/fw_cfg.c b/hw/nvram/fw_cfg.c
>> > index 7dc3ac378e..1a9ec44232 100644
>> > --- a/hw/nvram/fw_cfg.c
>> > +++ b/hw/nvram/fw_cfg.c
>> > @@ -247,10 +247,11 @@ static void fw_cfg_reboot(FWCfgState *s)
>> >  
>> >      if (reboot_timeout) {
>> >          rt_val = qemu_opt_get_number(opts, "reboot-timeout", -1);
>> > +
>> >          /* validate the input */
>> > -        if (rt_val < 0 || rt_val > 0xffff) {
>> > +        if (rt_val < -1 || rt_val > 0xffff) {
>> >              error_report("reboot timeout is invalid,"
>> > -                         "it should be a value between 0 and 65535");
>> > +                         "it should be a value between -1 and 65535");
>> >              exit(1);
>> >          }
>> >      }
>> 
>> Semantic conflict with "PATCH] qemu-options.hx: Update for
>> reboot-timeout parameter", Message-Id:
>> <address@hidden>.
>
> Thanks for spotting that.
> I think Han and also submitted patches to review it from libvirt
> and it wasn't obvious what to do.  (Cc'd Han in).
>
>> I'm too tired right now to risk an opinion on which one we want.
>
> As is everyone else !  The problem here is that its documented
> as a valid thing to do, and libvirt does it, and you might have 
> a current XML file that did it.  Now I think you could change libvirt
> to omit the reboot-timeout parameter if it was called with -1.
>
> So given its a documented thing in both qemu and libvirt xml
> if we want to remove it then it sohuld be deprecated properly - but it's
> already broken.

Since commit ee5d0f89d, v4.0.0.

If that commit had not made it into a release, we'd certainly treat the
loss of "-1 means don't reboot" as regression.

But it has.  We can treat it as a regression anyway.  We can also
declare "ship has sailed".

I'm leaning towads the former.

If we restore "-1 means don't reboot", then I don't see a need to
deprecate it.  Just keep it.

What do you think?