Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Wed, 23 Jun 2021 17:19:27 -0700
From:   "Paul E. McKenney" <paulmck@kernel.org>
To:     Nick Desaulniers <ndesaulniers@google.com>
Cc:     aneesh.kumar@linux.ibm.com, LKML <linux-kernel@vger.kernel.org>,
        Linux Next Mailing List <linux-next@vger.kernel.org>,
        Stephen Rothwell <sfr@canb.auug.org.au>,
        Marco Elver <elver@google.com>,
        clang-built-linux <clang-built-linux@googlegroups.com>
Subject: Re: Build failure in -next
Message-ID: <20210624001927.GS4397@paulmck-ThinkPad-P17-Gen-1>
Reply-To: paulmck@kernel.org
References: <20210623223015.GA315292@paulmck-ThinkPad-P17-Gen-1>
 <CAKwvOd=Y1fhJM7NpotvjNy3OE+JtqEBy046ctwE=cqV_ge5tgw@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CAKwvOd=Y1fhJM7NpotvjNy3OE+JtqEBy046ctwE=cqV_ge5tgw@mail.gmail.com>
Precedence: bulk

On Wed, Jun 23, 2021 at 04:39:11PM -0700, Nick Desaulniers wrote:
> On Wed, Jun 23, 2021 at 3:30 PM Paul E. McKenney <paulmck@kernel.org> wrote:
> >
> > Hello, Aneesh!
> >
> > Yesterday evening's next-20210622 testing gave me the following
> > kernel-build error:
> >
> > ld: mm/mremap.o: in function `move_huge_pud':
> > /home/git/linux-next/mm/mremap.c:372: undefined reference to `__compiletime_assert_395'
> >
> > Bisection landed on this commit:
> >
> > 257121c5aabe ("mm/mremap: convert huge PUD move to separate helper")
> >
> > I have no idea how this commit relates to that error message, but
> > reverting this commit on top of next-20210622 really does get rid of
> > the problem.
> >
> > The following reproducer provokes this error:
> >
> > tools/testing/selftests/rcutorture/bin/kvm.sh --allcpus --torture lock --configs LOCK07 --build-only --kconfig "CONFIG_DEBUG_LOCK_ALLOC=y CONFIG_PROVE_LOCKING=y" --kmake-arg "CC=clang-11"
> >
> > Run the above command in the top-level directory of your -next source
> > tree, and using this compiler:
> >
> > $ clang-11 -v
> > Ubuntu clang version 11.1.0-++20210428103817+1fdec59bffc1-1~exp1~20210428204431.166
> > Target: x86_64-pc-linux-gnu
> >
> > Thoughts?
> >
> >                                                         Thanx, Paul
> 
> ++beers_owed; for the report and bisection. Also reported
> https://lore.kernel.org/lkml/YM0mrZIPM+sWTDHf@Ryzen-9-3900X.localdomain/,
> let's chat over there.

And thank you for the redirection!

							Thanx, Paul