Re: [PATCH v2 0/5] Define _GNU_SOURCE for sources using

[Edward Liaw <edliaw@xxxxxxxxxx>]

On Wed, May 8, 2024 at 6:47 AM Sean Christopherson <seanjc@xxxxxxxxxx> wrote:
>
> On Tue, May 07, 2024, Edward Liaw wrote:
> > 809216233555 ("selftests/harness: remove use of LINE_MAX") introduced
> > asprintf into kselftest_harness.h, which is a GNU extension and needs
> > _GNU_SOURCE to either be defined prior to including headers or with the
> > -D_GNU_SOURCE flag passed to the compiler.
> >
> > v1: https://lore.kernel.org/linux-kselftest/20240430235057.1351993-1-edliaw@xxxxxxxxxx/
> > v2: add -D_GNU_SOURCE to KHDR_INCLUDES so that it is in a single
> > location.  Remove #define _GNU_SOURCE from source code to resolve
> > redefinition warnings.
> >
> > Edward Liaw (5):
> >   selftests: Compile kselftest headers with -D_GNU_SOURCE
> >   selftests/sgx: Include KHDR_INCLUDES in Makefile
> >   selftests: Include KHDR_INCLUDES in Makefile
> >   selftests: Drop define _GNU_SOURCE
> >   selftests: Drop duplicate -D_GNU_SOURCE
>
> Can you rebase this on top of linux-next?  I have a conflicting fix[*] for the
> KVM selftests queued for 6.10, and I would prefer not to drop that commit at
> this stage as it would require a rebase of a pile of other commits.

Ok, I'll do that.

>
> And I doubt KVM is the only subsystem that has a targeted fix for the _GNU_SOURCE
> mess.
>
> If we want/need to get a fix into 6.9, then IMO we should just revert 809216233555
> ("selftests/harness: remove use of LINE_MAX"), as that came in quite late in the
> 6.9 cycle, and I don't think it's feasible to be 100% confident that globally
> defining _GNU_SOURCE works for all selftests, i.e. we really should have a full
> cycle for folks to test.

That sounds reasonable to me.  In this thread Tao suggested reverting
back to 809216233555 and using a fixed value in place of LINE_MAX to
fix 38c957f07038
https://lore.kernel.org/linux-kselftest/20240508070003.2acdf9b4@xxxxxxxxxx/

>
> [*] https://github.com/kvm-x86/linux/commit/730cfa45b5f4