Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.32 as permitted sender) client-ip=23.128.96.32;
MIME-Version: 1.0
References: <CA+G9fYsCskpn_TNpSwLq9HGUgtT=aZpDzs7SVrqpa9WmyYFaxQ@mail.gmail.com>
 <ZTqGBzOQd4Oi3e9j@FVFF77S0Q05N.cambridge.arm.com> <CAMj1kXE8VrG6aPsjByd83kavw7He6vn=DszhJfAd-TfP9y8VBA@mail.gmail.com>
 <CA+G9fYuQxUhsrL_=uYSAdotU1_Wx7iu5PxFuG9EzWgBE2nMjcw@mail.gmail.com> <CAMj1kXESknQ40SZRMFv6Vv32x-2mSuMyOxoURQwwO1apQ+m=jA@mail.gmail.com>
In-Reply-To: <CAMj1kXESknQ40SZRMFv6Vv32x-2mSuMyOxoURQwwO1apQ+m=jA@mail.gmail.com>
From:   Naresh Kamboju <naresh.kamboju@linaro.org>
Date:   Mon, 30 Oct 2023 13:37:39 +0530
Message-ID: <CA+G9fYv3Ph6UDpW1uhoXD5QBE4tAZKpUkVy-Oo9NNrghChL_+A@mail.gmail.com>
Subject: Re: qemu-arm64: handle_futex_death - kernel/futex/core.c:661 - Unable
 to handle kernel unknown 43 at virtual address
To:     Ard Biesheuvel <ardb@kernel.org>
Cc:     Mark Rutland <mark.rutland@arm.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will.deacon@arm.com>,
        Oliver Upton <oliver.upton@linux.dev>,
        Linux-Next Mailing List <linux-next@vger.kernel.org>,
        open list <linux-kernel@vger.kernel.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        lkft-triage@lists.linaro.org, Arnd Bergmann <arnd@arndb.de>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@kernel.org>,
        Anders Roxell <anders.roxell@linaro.org>,
        Dan Carpenter <dan.carpenter@linaro.org>,
        LTP List <ltp@lists.linux.it>, Petr Vorel <pvorel@suse.cz>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Sat, 28 Oct 2023 at 13:12, Ard Biesheuvel <ardb@kernel.org> wrote:
>
> On Fri, 27 Oct 2023 at 12:57, Naresh Kamboju <naresh.kamboju@linaro.org> wrote:
> >
> > On Thu, 26 Oct 2023 at 21:09, Ard Biesheuvel <ardb@kernel.org> wrote:
> > >
> > > On Thu, 26 Oct 2023 at 17:30, Mark Rutland <mark.rutland@arm.com> wrote:
> > > >
> > > > On Thu, Oct 26, 2023 at 08:11:26PM +0530, Naresh Kamboju wrote:
> > > > > Following kernel crash noticed on qemu-arm64 while running LTP syscalls
> > > > > set_robust_list test case running Linux next 6.6.0-rc7-next-20231026 ...
> > > > It looks like this is fallout from the LPA2 enablement.
> > > >
> > > > According to the latest ARM ARM (ARM DDI 0487J.a), page D19-6475, that "unknown
> > > > 43" (0x2b / 0b101011) is the DFSC for a level -1 translation fault:
> > > >
> > > >         0b101011 When FEAT_LPA2 is implemented:
> > > >                  Translation fault, level -1.
> > > >
> > > > It's triggered here by an LDTR in a get_user() on a bogus userspace address.
> > > > The exception is expected, and it's supposed to be handled via the exception
> > > > fixups, but the LPA2 patches didn't update the fault_info table entries for all
> > > > the level -1 faults, and so those all get handled by do_bad() and don't call
> > > > fixup_exception(), causing them to be fatal.
> > > >
> > > > It should be relatively simple to update the fault_info table for the level -1
> > > > faults, but given the other issues we're seeing I think it's probably worth
> > > > dropping the LPA2 patches for the moment.
> > > >
> > >
> > > Thanks for the analysis Mark.
> > >
> > > I agree that this should not be difficult to fix, but given the other
> > > CI problems and identified loose ends, I am not going to object to
> > > dropping this partially or entirely at this point. I'm sure everybody
> > > will be thrilled to go over those 60 patches again after I rebase them
> > > onto v6.7-rc1 :-)
> >
> > I am happy to test any proposed fix patch.
> >
>
> Thanks Naresh. Patch attached.

This patch did not solve the reported problem.
Test log links,
 - https://tuxapi.tuxsuite.com/v1/groups/linaro/projects/naresh/tests/2XTP1lXcUUscT357YaAm2G1AhpS

- Naresh