Re: [PATCH 2/2] efi: Stop using StdErr

[Ross Lagerwall <ross.lagerwall@xxxxxxxxxx>]

On Wed, Aug 6, 2025 at 7:32 AM Jan Beulich <jbeulich@xxxxxxxx> wrote:
>
> On 05.08.2025 18:32, Ross Lagerwall wrote:
> > Xen's use of StdErr is inconsistent. Some boot errors are reported using
> > PrintErr() which uses StdErr and some are reported using blexit() which
> > uses StdOut.
>
> ... with PrintErrMesg() having
>
>     StdOut = StdErr;
>
> apparently to address at least some of the inconsistencies. Perhaps
> blexit(), when not passed NULL, should similarly override StdOut.
>
> > On my test system using OVMF, StdErr is not displayed on the emulated
> > screen. Looking at other EFI applications, StdErr is just used for debug
> > messages if at all.
>
> That's hardly how StdErr was meant to be used. And at the risk of being
> flamed for saying so, looking at other EFI applications (without saying
> of what prominence or origin they are) can hardly serve as a justification.
> If OVMF doesn't set up StdErr correctly (despite being configured / set up
> correctly), and if that can't be fixed there, imo what you want as a
> workaround is a command line option to override StdErr by StdOut even when
> SystemTable->StdErr is non-NULL.
>
> Along the lines of the comment further up, inconsistencies in the use of
> StdErr vs StdOut may want addressing (separately).
>

I tried to reproduce this on a few physical hosts and was unable to so
for now I'll chalk it up as an OVMF bug / configuration issue and
retract this patch. And yes, the StdErr vs StdOut issue should probably
be addressed separately.

Thanks,
Ross