Re: [PATCH 5/5] MAINTAINERS: Update KVM/MIPS maintainers

[Yu Zhao <yuzhao@google.com>]

On Mon, Jun 26, 2023 at 2:00 AM Huacai Chen <chenhuacai@kernel.org> wrote:
>
> Hi, Zhao,
>
> On Sun, Jun 18, 2023 at 10:51 AM Yu Zhao <yuzhao@google.com> wrote:
> >
> > On Sat, Jun 17, 2023 at 8:13 PM Huacai Chen <chenhuacai@kernel.org> wrote:
> > >
> > > On Sat, Jun 17, 2023 at 9:52 AM Yu Zhao <yuzhao@google.com> wrote:
> > > >
> > > > On Fri, Jun 16, 2023 at 10:23:22AM +0200, Thomas Bogendoerfer wrote:
> > > > > On Fri, Jun 16, 2023 at 01:18:31AM -0600, Yu Zhao wrote:
> > > > > > On Tue, Jul 28, 2020 at 23:58:20PM -0700, Huacai Chen wrote:
> > > > > > > James Hogan has become inactive for a long time and leaves KVM for MIPS
> > > > > > > orphan. I'm working on KVM/Loongson and attempt to make it upstream both
> > > > > > > in kernel and QEMU, while Aleksandar Markovic is already a maintainer of
> > > > > > > QEMU/MIPS. We are both interested in QEMU/KVM/MIPS, and we have already
> > > > > > > made some contributions in kernel and QEMU. If possible, we want to take
> > > > > > > the KVM/MIPS maintainership.
> > > > > > >
> > > > > > > Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
> > > > > > > Reviewed-by: Aleksandar Markovic <aleksandar.qemu.devel@gmail.com>
> > > > > > > Signed-off-by: Huacai Chen <chenhc@lemote.com>
> > > > > > > ---
> > > > > > >  MAINTAINERS | 4 +++-
> > > > > > >  1 file changed, 3 insertions(+), 1 deletion(-)
> > > > > > >
> > > > > > > diff --git a/MAINTAINERS b/MAINTAINERS
> > > > > > > index bddc79a..5f9c2fd 100644
> > > > > > > --- a/MAINTAINERS
> > > > > > > +++ b/MAINTAINERS
> > > > > > > @@ -9441,9 +9441,11 @@ F: arch/arm64/kvm/
> > > > > > >  F:       include/kvm/arm_*
> > > > > > >
> > > > > > >  KERNEL VIRTUAL MACHINE FOR MIPS (KVM/mips)
> > > > > > > +M:       Huacai Chen <chenhc@lemote.com>
> > > > > > > +M:       Aleksandar Markovic <aleksandar.qemu.devel@gmail.com>
> > > > > > >  L:       linux-mips@vger.kernel.org
> > > > > > >  L:       kvm@vger.kernel.org
> > > > > > > -S:       Orphan
> > > > > > > +S:       Maintained
> > > > > > >  F:       arch/mips/include/asm/kvm*
> > > > > > >  F:       arch/mips/include/uapi/asm/kvm*
> > > > > > >  F:       arch/mips/kvm/
> > > > > >
> > > > > > Hi,
> > > > > >
> > > > > > Is kvm/mips still maintained? Thanks.
> > > > > >
> > > > > > I tried v6.4-rc6 and hit the following crash. It seems it has been broken since
> > > > > >
> > > > > >   commit 45c7e8af4a5e3f0bea4ac209eea34118dd57ac64
> > > > > >   Author: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
> > > > > >   Date:   Mon Mar 1 16:29:57 2021 +0100
> > > > > >
> > > > > >       MIPS: Remove KVM_TE support
> > > > >
> > > > > ok, I see what I missed when removing TE support, d'oh. Does the patch
> > > > > below fix the issue for you ?
> > > >
> > > > Thanks!
> > > >
> > > > It made some progress but somehow crashed the guest kernel.
> > > >
> > > > $ qemu-system-mips64el --version
> > > > QEMU emulator version 7.2.2 (Debian 1:7.2+dfsg-7)
> > > > Copyright (c) 2003-2022 Fabrice Bellard and the QEMU Project developers
> > > >
> > > > # w/o KVM
> > > >
> > > >   # malta: working (but slow)
> > > >
> > > >     $ qemu-system-mips64el -nographic -kernel lede-malta-le64-vmlinux-initramfs.elf
> > > >     [    0.000000] Linux version 4.9.58 (buildbot@builds) (gcc version 5.5.0 (LEDE GCC 5.5.0 r5218-f90f94d) ) #0 SMP Wed Nov 1 21:08:14 2017
> > > >     ...
> > > >
> > > >   # loongson3-virt: hanged
> > > >
> > > >     $ qemu-system-mips64el -M loongson3-virt -m 512m -nographic -kernel vmlinuz-6.1.0-9-loongson-3 -initrd initrd.gz
> > > >     [    0.000000] Linux version 6.1.0-9-loongson-3 (debian-kernel@lists.debian.org) (gcc-12 (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40) #1 SMP PREEMPT Debian 6.1.27-1 (2023-05-08)
> > > >     ...
> > > >     [    0.000000] Initmem setup node 0 [mem 0x0000000000000000-0x000000009fffffff]
> > > >
> > > > # w/ KVM
> > > >
> > > >   # malta: qemu error
> > > >
> > > >     $ sudo qemu-system-mips64el -M accel=kvm -nographic -kernel lede-malta-le64-vmlinux-initramfs.elf
> > > >     qemu-system-mips64el: KVM guest kernels must be linked in useg. Did you forget to enable CONFIG_KVM_GUEST?
> > > >
> > > >   # loongson3-virt: qemu error
> > > >
> > > >     $ sudo qemu-system-mips64el -M loongson3-virt,accel=kvm -m 512m -nographic -kernel vmlinuz-6.1.0-9-loongson-3 -initrd initrd.gz
> > > >     qemu-system-mips64el: ../../accel/kvm/kvm-all.c:2310: kvm_init: Assertion `TARGET_PAGE_SIZE <= qemu_real_host_page_size()' failed.
> > > >     Aborted
> > > >
> > > > $ qemu-system-mips64el --version
> > > > QEMU emulator version 8.0.2 (Debian 1:8.0.2+dfsg-1)
> > > > Copyright (c) 2003-2022 Fabrice Bellard and the QEMU Project developers
> > > >
> > > > # w/o KVM
> > > >
> > > >   # malta: no change
> > > >   # loongson3-virt: no change
> > > >
> > > > # w/ KVM
> > > >
> > > >   # loongson3-virt: the same qemu error
> > > >
> > > >   # malta: booted very fast but guest crashed:
> > > >
> > > > $ sudo qemu-system-mips64el -M accel=kvm -nographic -kernel lede-malta-le64-vmlinux-initramfs.elf
> > > > [    0.000000] Linux version 4.9.58 (buildbot@builds) (gcc version 5.5.0 (LEDE GCC 5.5.0 r5218-f90f94d) ) #0 SMP Wed Nov 1 21:08:14 2017
> >
> > ...
> >
> > > > [    0.402570] Kernel panic - not syncing: Fatal exception
> > > > [    0.404311] Rebooting in 1 seconds..
> > > > [    2.385408] Reboot failed -- System halted
> > > >
> > > > openwrt/malta: https://downloads.openwrt.org/snapshots/targets/malta/le64/
> > > > debian/loongson-3: https://deb.debian.org/debian/dists/sid/main/installer-mips64el/current/images/
> > > > debian/malta: not working
> > >
> > > I have reproduced the problem, and I hope I can fix it in a few days,
> >
> > That's great. Thanks a lot!
> I fixed the KVM problems on Loongson [1][2][3]. However, you have
> tried [1] but still have problems, while [2] and [3] are specific to
> Loongson, so maybe you are still unable to use KVM.
>
> [1] https://lore.kernel.org/linux-mips/20230626074919.1871944-1-chenhuacai@loongson.cn/T/#u
> [2] https://lore.kernel.org/linux-mips/20230626075014.1872632-1-chenhuacai@loongson.cn/T/#u
> [3] https://lore.kernel.org/linux-mips/20230626075047.1872818-1-chenhuacai@loongson.cn/T/#u

Thanks for the update. I'll take a look if I get a chance.