Re: [edk2-devel] [PATCH v2 2/2] ArmVirtPkg/ArmVirtQemu: Avoid early ID map on ThunderX

["Ard Biesheuvel" <ardb@kernel.org>]

On Thu, 9 Feb 2023 at 16:15, Ard Biesheuvel <ardb@kernel.org> wrote:
>
> On Tue, 7 Feb 2023 at 13:58, Oliver Steffen <osteffen@redhat.com> wrote:
> >
> > On Tue, Feb 7, 2023 at 12:57 PM Ard Biesheuvel <ardb@kernel.org> wrote:
> >>
> >> On Tue, 7 Feb 2023 at 11:51, Oliver Steffen <osteffen@redhat.com> wrote:
> >> >
> >> > On Thu, Feb 2, 2023 at 12:09 PM Oliver Steffen <osteffen@redhat.com> wrote:
> >> >>
> >> >>
> >> >> On Wed, Feb 1, 2023 at 2:29 PM Ard Biesheuvel <ardb@kernel.org> wrote:
> >> >>>
> >> >>> On Wed, 1 Feb 2023 at 13:59, Oliver Steffen <osteffen@redhat.com> wrote:
> >> >>> >
> >> >>> > On Wed, Feb 1, 2023 at 12:52 PM Ard Biesheuvel <ardb@kernel.org> wrote:
> >> >>> >>
> >> >>> >> On Wed, 1 Feb 2023 at 10:14, Oliver Steffen <osteffen@redhat.com> wrote:
> >> >>> >> >
> >> >>
> >> >> [...]
> >> >>>
> >> >>> >> > I am sorry, this story does not seem to be over yet.
> >> >>> >> >
> >> >>> >> > We are using the Erratum patch and also included the commit 406504c7 in
> >> >>> >> > the kernel.
> >> >>> >> > Now the firmware crashes sometimes (10 out of 89 tests).
> >> >>> >> >
> >> >>> >>
> >> >>> >> Thanks for the report. Is this still on ThunderX2?
> >> >>> >>
> >> >>> >> > Any hints are very welcome!
> >> >>> >> >
> >> >>> >>
> >> >>> >> Do  you have access to those build artifacts?
> >> >>> >
> >> >>> >
> >> >>> > https://kojihub.stream.centos.org/kojifiles/work/tasks/5251/1835251/edk2-aarch64-20221207gitfff6d81270b5-4.el9.test.noarch.rpm
> >> >>> >
> >> >>> > and/or here:
> >> >>> >
> >> >>> > https://kojihub.stream.centos.org/koji/taskinfo?taskID=1835251
> >> >>> >
> >> >>> > Source for reference:
> >> >>> > https://gitlab.com/redhat/centos-stream/src/edk2/-/merge_requests/24
> >> >>> >
> >> >>>
> >> >>> Any chance the .dll files (which are actually ELF executables) have
> >> >>> been preserved somewhere?
> >> >>
> >> >> Here is the build folder (~90MB):
> >> >> https://gitlab.com/osteffen/thunderx2-debug/-/raw/main/armvirt-thunderx2-issue.tar.xz
> >> >>
> >> >> I am waiting for the tests with the additional debug output to run.
> >> >
> >> >
> >> > We reran the test suite with the Erratum and the additional debug
> >> > output enabled.  Strangely, the problem does not occur anymore, the
> >> > firmware boots up normally.
> >> >
> >> > We retried the tests without the additional debug output.
> >> > RHEL ships two firmware flavors for AARCH64: a silent and a verbose
> >> > version.
> >>
> >> Are these RELEASE vs DEBUG builds?
> >
> >
> > All builds are DEBUG, just the amount of information printed on
> > the serial is different (almost zero for the "silent" one.)
> >
> >>
> >> > Both were tried. We see no problems with the verbose
> >> > one. The silent one fails noticeably more often if a software TPM device
> >> > is present.
> >> >
> >>
> >> This smells like some missing cache or TLB maintenance - the verbose
> >> one exits to the host much more often, and likely relies on cache/TLB
> >> maintenance occurring in the hypervisor.
> >>
> >> So the build always includes TPM support but the issue only occurs
> >> when the sw TPM is actually exposed by QEMU?
> >
> >
> > Yes.
> > All builds include support for TPM, but the issue occurs more frequently
> > if a sw TPM is exposed by QEMU.
> >
>
> Any chance you could provide a specific command line for launching
> QEMU? I am trying to reproduce this, but I am not making any progress.
>
> >>
> >> > Could this be related to how much stuff is going on in the early phase
> >> > of the firmware (when logging is enabled: formatting of messages and
> >> > sending to serial port...) ?
> >> >
> >>
> >> I'll try to see if I can rig something up that logs into a buffer
> >> rather than straight to the serial, and dump it all out when handling
> >> the crash
> >>
>
> This takes a bit more time than I can afford to spend on this atm, and
> I'd like to be able to reproduce before I go down this rabbit hole.

Have there been any developments regarding this issue?