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;
MIME-Version: 1.0
References: <CA+G9fYvHze+hKROmiB0uL90S8h9ppO9S9Xe7RWwv808QwOd_Yw@mail.gmail.com>
 <CAHk-=wg5-P79Hr4iaC_disKR2P+7cRVqBA9Dsria9jdVwHo0+A@mail.gmail.com>
 <CA+G9fYv=DUanNfL2yza=y9kM7Y9bFpVv22Wd4L9NP28i0y7OzA@mail.gmail.com> <CA+G9fYudry0cXOuSfRTqHKkFKW-sMrA6Z9BdQFmtXsnzqaOgPg@mail.gmail.com>
In-Reply-To: <CA+G9fYudry0cXOuSfRTqHKkFKW-sMrA6Z9BdQFmtXsnzqaOgPg@mail.gmail.com>
From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Thu, 22 Oct 2020 16:43:29 -0700
Message-ID: <CAHk-=who8WmkWuuOJeGKa-7QCtZHqp3PsOSJY0hadyywucPMcQ@mail.gmail.com>
Subject: Re: mmstress[1309]: segfault at 7f3d71a36ee8 ip 00007f3d77132bdf sp
 00007f3d71a36ee8 error 4 in libc-2.27.so[7f3d77058000+1aa000]
To:     Naresh Kamboju <naresh.kamboju@linaro.org>
Cc:     open list <linux-kernel@vger.kernel.org>,
        linux-m68k <linux-m68k@lists.linux-m68k.org>,
        X86 ML <x86@kernel.org>, LTP List <ltp@lists.linux.it>,
        lkft-triage@lists.linaro.org,
        Linux-Next Mailing List <linux-next@vger.kernel.org>,
        linux-mm <linux-mm@kvack.org>,
        kasan-dev <kasan-dev@googlegroups.com>,
        Christian Brauner <christian.brauner@ubuntu.com>,
        Ingo Molnar <mingo@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        "Matthew Wilcox (Oracle)" <willy@infradead.org>,
        "Peter Zijlstra (Intel)" <peterz@infradead.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Geert Uytterhoeven <geert@linux-m68k.org>,
        Viresh Kumar <viresh.kumar@linaro.org>,
        zenglg.jy@cn.fujitsu.com, Stephen Rothwell <sfr@canb.auug.org.au>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        Dmitry Vyukov <dvyukov@google.com>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Thu, Oct 22, 2020 at 1:55 PM Naresh Kamboju
<naresh.kamboju@linaro.org> wrote:
>
> The bad commit points to,
>
> commit d55564cfc222326e944893eff0c4118353e349ec
> x86: Make __put_user() generate an out-of-line call
>
> I have reverted this single patch and confirmed the reported
> problem is not seen anymore.

Thanks. Very funky, but thanks. I've been running that commit on my
machine for over half a year, and it still looks "trivially correct"
to me, but let me go look at it one more time. Can't argue with a
reliable bisect and revert..

            Linus