Re: error: redefinition of ‘dax_supported’

[Dan Williams]

On Mon, Sep 21, 2020 at 11:35 AM Nick Desaulniers
<ndesaulniers at google.com> wrote:
>
> Hello DAX maintainers,
> I noticed our PPC64LE builds failing last night:
> https://travis-ci.com/github/ClangBuiltLinux/continuous-integration/jobs/388047043
> https://travis-ci.com/github/ClangBuiltLinux/continuous-integration/jobs/388047056
> https://travis-ci.com/github/ClangBuiltLinux/continuous-integration/jobs/388047099
> and looking on lore, I see a fresh report from KernelCI against arm:
> https://lore.kernel.org/linux-next/?q=dax_supported
>
> Can you all please take a look?  More concerning is that I see this
> failure on mainline.  It may be interesting to consider how this was
> not spotted on -next.

The failure is fixed with commit 88b67edd7247 ("dax: Fix compilation
for CONFIG_DAX && !CONFIG_FS_DAX"). I rushed the fixes that led to
this regression with insufficient exposure because it was crashing all
users. I thought the 2 kbuild-robot reports I squashed covered all the
config combinations, but there was a straggling report after I sent my
-rc6 pull request.

The baseline process escape for all of this was allowing a unit test
triggerable insta-crash upstream in the first instance necessitating
an urgent fix.