Re: [PATCH dwarves 1/2] tests/flexible_arrays: redirect stderr to avoid warnings

[Arnaldo Carvalho de Melo <acme@kernel.org>]

On Thu, Oct 24, 2024 at 02:01:21PM +0100, Alan Maguire wrote:
> On 24/10/2024 13:13, Arnaldo Carvalho de Melo wrote:
> > 
> > On Thu, Oct 24, 2024, 8:26 AM Alan Maguire <alan.maguire@oracle.com
> > <mailto:alan.maguire@oracle.com>> wrote:
> > 
> >     With recent kernel, saw
> > 
> >       2: Flexible arrays accounting: WARNING: still unsuported
> >     BTF_KIND_DECL_TAG(bpf_fastcall) for bpf_cast_to_kern_ctx already
> >     with attribute (bpf_kfunc), ignoring
> >     WARNING: still unsuported BTF_KIND_DECL_TAG(bpf_fastcall) for
> >     bpf_rdonly_cast already with attribute (bpf_kfunc), ignoring
> >     Ok
> > 
> >     Redirect pahole output to avoid seeing the stderr messaging.
> > 
> > 
> > 
> > This is something I kinda expect from these tests, now I want to get
> > hold of such a vmlinux to understand what's needed to address the warning. 
> >  
> > Maybe have a quiet mode for testing just what's supported in a released
> > version when tested by packagers?
> > 
> > Maybe not, as knowing that they have a kernel with a feature unsupported
> > by pahole may be important and should elicit measures to either get a
> > newer version of pahole or disable a still experimental feature in their
> > kernel? 
> > 
> > WDYT?
> > 
> 
> Good point on the visibility of warnings being useful. We have VERBOSE
> already so it seems like having QUIET (implying stderr > /dev/null)
> would be easiest to add at this stage rather than having to add multiple
> levels to VERBOSE. Maybe QUIET isn't even needed though as the above is
> still clearly a test pass, and the messaging doesn't interfere with test
> success.
> 
> Probably best to drop this one for now anyway..

That is what I did, agreed.

I adapted the second one to this fact and applied it, thanks!

- Arnaldo

> > 
> > 
> >     Signed-off -by: Alan Maguire <alan.maguire@oracle.com
> >     <mailto:alan.maguire@oracle.com>>
> >     ---
> >      tests/flexible_arrays.sh | 2 +-
> >      1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> >     diff --git a/tests/flexible_arrays.sh b/tests/flexible_arrays.sh
> >     index 7c21253..e9e3cb0 100755
> >     --- a/tests/flexible_arrays.sh
> >     +++ b/tests/flexible_arrays.sh
> >     @@ -20,7 +20,7 @@ pretty=$(mktemp /tmp/flexible_arrays.data.sh
> >     <http://flexible_arrays.data.sh>.XXXXXX.c)
> > 
> >      echo -n "Flexible arrays accounting: "
> > 
> >     -for struct in $(pahole -F btf --sizes --
> >     with_embedded_flexible_array $vmlinux | cut -f1) ; do
> >     +for struct in $(pahole -F btf --sizes --
> >     with_embedded_flexible_array $vmlinux 2>/dev/null| cut -f1) ; do
> >             pahole $struct > $pretty
> > 
> >             # We need to check for just one tab before the comment as
> >     when expanding unnamed
> >     -- 
> >     2.43.5
> >