On 11 June 2020 at 04:47 pm, Christian Zigotzky wrote:
On 10 June 2020 at 01:23 pm, Christian Zigotzky wrote:
On 10 June 2020 at 11:06 am, Christian Zigotzky wrote:
On 10 June 2020 at 00:18 am, Christian Zigotzky wrote:
Hello,

KVM-PR doesn't work anymore on my Nemo board [1]. I figured out that the Git kernels and the kernel 5.7 are affected.

Error message: Fienix kernel: kvmppc_exit_pr_progint: emulation at 700 failed (00000000)

I can boot virtual QEMU PowerPC machines with KVM-PR with the kernel 5.6 without any problems on my Nemo board.

I tested it with QEMU 2.5.0 and QEMU 5.0.0 today.

Could you please check KVM-PR on your PowerPC machine?

Thanks,
Christian

[1] https://en.wikipedia.org/wiki/AmigaOne_X1000

I figured out that the PowerPC updates 5.7-1 [1] are responsible for the KVM-PR issue. Please test KVM-PR on your PowerPC machines and check the PowerPC updates 5.7-1 [1].

Thanks

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d38c07afc356ddebaa3ed8ecb3f553340e05c969


I tested the latest Git kernel with Mac-on-Linux/KVM-PR today. Unfortunately I can't use KVM-PR with MoL anymore because of this issue (see screenshots [1]). Please check the PowerPC updates 5.7-1.

Thanks

[1]
- https://i.pinimg.com/originals/0c/b3/64/0cb364a40241fa2b7f297d4272bbb8b7.png - https://i.pinimg.com/originals/9a/61/d1/9a61d170b1c9f514f7a78a3014ffd18f.png

Hi All,

I bisected today because of the KVM-PR issue.

Result:

9600f261acaaabd476d7833cec2dd20f2919f1a0 is the first bad commit
commit 9600f261acaaabd476d7833cec2dd20f2919f1a0
Author: Nicholas Piggin <npig...@gmail.com>
Date:   Wed Feb 26 03:35:21 2020 +1000

    powerpc/64s/exception: Move KVM test to common code

    This allows more code to be moved out of unrelocated regions. The
    system call KVMTEST is changed to be open-coded and remain in the
    tramp area to avoid having to move it to entry_64.S. The custom nature
    of the system call entry code means the hcall case can be made more
    streamlined than regular interrupt handlers.

    mpe: Incorporate fix from Nick:

    Moving KVM test to the common entry code missed the case of HMI and
    MCE, which do not do __GEN_COMMON_ENTRY (because they don't want to
    switch to virt mode).

    This means a MCE or HMI exception that is taken while KVM is running a
    guest context will not be switched out of that context, and KVM won't
    be notified. Found by running sigfuz in guest with patched host on
    POWER9 DD2.3, which causes some TM related HMI interrupts (which are
    expected and supposed to be handled by KVM).

    This fix adds a __GEN_REALMODE_COMMON_ENTRY for those handlers to add
    the KVM test. This makes them look a little more like other handlers
    that all use __GEN_COMMON_ENTRY.

    Signed-off-by: Nicholas Piggin <npig...@gmail.com>
    Signed-off-by: Michael Ellerman <m...@ellerman.id.au>
    Link: https://lore.kernel.org/r/20200225173541.1549955-13-npig...@gmail.com

:040000 040000 ec21cec22d165f8696d69532734cb2985d532cb0 87dd49a9cd7202ec79350e8ca26cea01f1dbd93d M    arch

-----

The following commit is the problem: powerpc/64s/exception: Move KVM test to common code [1]

These changes were included in the PowerPC updates 5.7-1. [2]

Another test:

git checkout d38c07afc356ddebaa3ed8ecb3f553340e05c969 (PowerPC updates 5.7-1 [2] ) -> KVM-PR doesn't work.

After that: git revert d38c07afc356ddebaa3ed8ecb3f553340e05c969 -m 1 -> KVM-PR works.

Could you please check the first bad commit? [1]

Thanks,
Christian


[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9600f261acaaabd476d7833cec2dd20f2919f1a0 [2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d38c07afc356ddebaa3ed8ecb3f553340e05c969

Hi All,

I tried to revert the __GEN_REALMODE_COMMON_ENTRY fix for the latest Git kernel and for the stable kernel 5.7.2 but without any success. There was lot of restructuring work during the kernel 5.7 development time in the PowerPC area so it isn't possible reactivate the old code. That means we have lost the whole KVM-PR support. I also reported this issue to Alexander Graf two days ago. He wrote: "Howdy :). It looks pretty broken. Have you ever made a bisect to see where the problem comes from?"

Please check the KVM-PR code.

Thanks,
Christian


Reply via email to