Boot issue with the latest Git kernel

Boot issue with the latest Git kernel

[Christian Zigotzky]

Hi All,

I tested the latest Git kernel today. [1]. Unfortunately it doesn't boot 
on my PowerPC machines.

Could you please test the latest Git kernel with your PowerPC machine?

BTW, it doesn't boot in a virtual QEMU PowerPC machine either.

Thanks,
Christian

[1] 
https://forum.hyperion-entertainment.com/viewtopic.php?f=58&p=50758&sid=3f816f078869510dea9fe4baca3605db#p50758

Re: Boot issue with the latest Git kernel

[Christophe Leroy]

Hi,


Le 04/06/2020 à 16:16, Christian Zigotzky a écrit :
> Hi All,
> 
> I tested the latest Git kernel today. [1]. Unfortunately it doesn't boot 
> on my PowerPC machines.
> 
> Could you please test the latest Git kernel with your PowerPC machine?
> 
> BTW, it doesn't boot in a virtual QEMU PowerPC machine either.
> 

Which machine/platform ? Which defconfig are you using ?

Christophe

Re: Boot issue with the latest Git kernel

[Christophe Leroy]

Le 04/06/2020 à 16:26, Christophe Leroy a écrit :
> Hi,
> 
> 
> Le 04/06/2020 à 16:16, Christian Zigotzky a écrit :
>> Hi All,
>>
>> I tested the latest Git kernel today. [1]. Unfortunately it doesn't 
>> boot on my PowerPC machines.
>>
>> Could you please test the latest Git kernel with your PowerPC machine?
>>
>> BTW, it doesn't boot in a virtual QEMU PowerPC machine either.
>>
> 
> Which machine/platform ? Which defconfig are you using ?
> 


And are you able to perform a 'git bisect' to identify the guilty commit ?

Thanks
Christophe

Re: Boot issue with the latest Git kernel

[Christian Zigotzky]

[-- Attachment #1: Type: text/plain, Size: 1111 bytes --]

Hello Christophe,

I tested it on my Nemo board with a P.A. Semi PA6T CPU [1], on my Cyrus+ board with a FSL P5040 CPU [2] and in a virtual e5500 QEMU machine. You can find the kernel configs in the following package.

Link: http://www.xenosoft.de/linux-image-5.8-alpha1-X1000_X5000.tar.gz

Cheers,
Christian

[1] https://en.m.wikipedia.org/wiki/AmigaOne_X1000
[2] https://www.amigaos.net/hardware/133/amigaone-x5000


> On 4. Jun 2020, at 16:29, Christophe Leroy <christophe.leroy@csgroup.eu> wrote:
> 
> 
> 
>> Le 04/06/2020 à 16:26, Christophe Leroy a écrit :
>> Hi,
>>> Le 04/06/2020 à 16:16, Christian Zigotzky a écrit :
>>> Hi All,
>>> 
>>> I tested the latest Git kernel today. [1]. Unfortunately it doesn't boot on my PowerPC machines.
>>> 
>>> Could you please test the latest Git kernel with your PowerPC machine?
>>> 
>>> BTW, it doesn't boot in a virtual QEMU PowerPC machine either.
>>> 
>> Which machine/platform ? Which defconfig are you using ?
> 
> 
> And are you able to perform a 'git bisect' to identify the guilty commit ?
> 
> Thanks
> Christophe

[-- Attachment #2: Type: text/html, Size: 2635 bytes --]

Re: Boot issue with the latest Git kernel

[Christian Zigotzky]

> On 4. Jun 2020, at 16:29, Christophe Leroy <christophe.leroy@csgroup.eu> wrote:
> 
> And are you able to perform a 'git bisect' to identify the guilty commit ?
> 
> Thanks
> Christophe

Hello Christophe,

Unfortunately I haven’t had time to bisect the latest Git kernel. Does it boot on your PowerPC machine?

Thanks,
Christian

Re: Boot issue with the latest Git kernel

[Christophe Leroy]

Le 04/06/2020 à 17:53, Christian Zigotzky a écrit :
> 
> 
>> On 4. Jun 2020, at 16:29, Christophe Leroy <christophe.leroy@csgroup.eu> wrote:
>>
>> And are you able to perform a 'git bisect' to identify the guilty commit ?
>>
>> Thanks
>> Christophe
> 
> Hello Christophe,
> 
> Unfortunately I haven’t had time to bisect the latest Git kernel. Does it boot on your PowerPC machine?
> 

Yes today's linux-next boots on my powerpc 8xx board.

Christophe

Re: Boot issue with the latest Git kernel

[Christian Zigotzky]

On 04 June 2020 at 7:15 pm, Christophe Leroy wrote:
> Yes today's linux-next boots on my powerpc 8xx board.
>
> Christophe
Hello Christophe,

Thanks for testing.

I was able to perform a 'git bisect' [1] and identified the bad commit. 
[2] I reverted this commit and after that the kernel boots and works 
without any problems.

Could you please check this commit?

Thanks,
Christian


[1] https://forum.hyperion-entertainment.com/viewtopic.php?p=50772#p50772
[2] 
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=2ba3e6947aed9bb9575eb1603c0ac6e39185d32a

Re: Boot issue with the latest Git kernel

[Christian Zigotzky]

Hi All,

It seems, someone has fixed the boot issue. The latest Git kernel boots 
on my PowerPC machines.

Thanks,
Christian


On 05 June 2020 at 6:23 pm, Christian Zigotzky wrote:
> On 04 June 2020 at 7:15 pm, Christophe Leroy wrote:
>> Yes today's linux-next boots on my powerpc 8xx board.
>>
>> Christophe
> Hello Christophe,
>
> Thanks for testing.
>
> I was able to perform a 'git bisect' [1] and identified the bad 
> commit. [2] I reverted this commit and after that the kernel boots and 
> works without any problems.
>
> Could you please check this commit?
>
> Thanks,
> Christian
>
>
> [1] https://forum.hyperion-entertainment.com/viewtopic.php?p=50772#p50772
> [2] 
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=2ba3e6947aed9bb9575eb1603c0ac6e39185d32a

Re: Boot issue with the latest Git kernel

[Aneesh Kumar K.V]

Christian Zigotzky <chzigotzky@xenosoft.de> writes:

> On 04 June 2020 at 7:15 pm, Christophe Leroy wrote:
>> Yes today's linux-next boots on my powerpc 8xx board.
>>
>> Christophe
> Hello Christophe,
>
> Thanks for testing.
>
> I was able to perform a 'git bisect' [1] and identified the bad commit. 
> [2] I reverted this commit and after that the kernel boots and works 
> without any problems.
>
> Could you please check this commit?
>
> Thanks,
> Christian
>
>
> [1] https://forum.hyperion-entertainment.com/viewtopic.php?p=50772#p50772
> [2] 
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=2ba3e6947aed9bb9575eb1603c0ac6e39185d32a

This was also reported here.

https://lore.kernel.org/linuxppc-dev/1591181457.9020.13.camel@abdul

-aneesh

PowerPC KVM-PR issue

[Christian Zigotzky]

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

Re: PowerPC KVM-PR issue

[Christian Zigotzky]

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

Re: PowerPC KVM-PR issue

[Christian Zigotzky]

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

Re: PowerPC KVM-PR issue

[Christian Zigotzky]

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

Re: PowerPC KVM-PR issue

[Christian Zigotzky]

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

Re: PowerPC KVM-PR issue

[Nicholas Piggin]

Excerpts from Christian Zigotzky's message of June 12, 2020 11:01 pm:
> 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 <npiggin@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 <npiggin@gmail.com>
>>     Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
>>     Link: 
>> https://lore.kernel.org/r/20200225173541.1549955-13-npiggin@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.

Hey, thanks for debugging it and reporting. I'm looking into it, will 
try to get a fix soon.

Thanks,
Nick

Re: PowerPC KVM-PR issue

[Nicholas Piggin]

Excerpts from Christian Zigotzky's message of June 12, 2020 11:01 pm:
> 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 <npiggin@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 <npiggin@gmail.com>
>>     Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
>>     Link: 
>> https://lore.kernel.org/r/20200225173541.1549955-13-npiggin@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.

Does this patch fix it for you?

The CTR register reload in the KVM interrupt path used the wrong save
area for SLB (and NMI) interrupts.

Fixes: 9600f261acaaa ("powerpc/64s/exception: Move KVM test to common code")
Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/kernel/exceptions-64s.S | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index e70ebb5c318c..fa080694e581 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -270,7 +270,7 @@ BEGIN_FTR_SECTION
 END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
 	.endif
 
-	ld	r10,PACA_EXGEN+EX_CTR(r13)
+	ld	r10,IAREA+EX_CTR(r13)
 	mtctr	r10
 BEGIN_FTR_SECTION
 	ld	r10,IAREA+EX_PPR(r13)
@@ -298,7 +298,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
 
 	.if IKVM_SKIP
 89:	mtocrf	0x80,r9
-	ld	r10,PACA_EXGEN+EX_CTR(r13)
+	ld	r10,IAREA+EX_CTR(r13)
 	mtctr	r10
 	ld	r9,IAREA+EX_R9(r13)
 	ld	r10,IAREA+EX_R10(r13)
-- 
2.23.0

Re: PowerPC KVM-PR issue

[Christian Zigotzky]

On 14 June 2020 at 02:53 pm, Nicholas Piggin wrote:
> Excerpts from Christian Zigotzky's message of June 12, 2020 11:01 pm:
>> 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 <npiggin@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 <npiggin@gmail.com>
>>>      Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
>>>      Link:
>>> https://lore.kernel.org/r/20200225173541.1549955-13-npiggin@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.
> Does this patch fix it for you?
>
> The CTR register reload in the KVM interrupt path used the wrong save
> area for SLB (and NMI) interrupts.
>
> Fixes: 9600f261acaaa ("powerpc/64s/exception: Move KVM test to common code")
> Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de>
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
>   arch/powerpc/kernel/exceptions-64s.S | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
> index e70ebb5c318c..fa080694e581 100644
> --- a/arch/powerpc/kernel/exceptions-64s.S
> +++ b/arch/powerpc/kernel/exceptions-64s.S
> @@ -270,7 +270,7 @@ BEGIN_FTR_SECTION
>   END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
>   	.endif
>   
> -	ld	r10,PACA_EXGEN+EX_CTR(r13)
> +	ld	r10,IAREA+EX_CTR(r13)
>   	mtctr	r10
>   BEGIN_FTR_SECTION
>   	ld	r10,IAREA+EX_PPR(r13)
> @@ -298,7 +298,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
>   
>   	.if IKVM_SKIP
>   89:	mtocrf	0x80,r9
> -	ld	r10,PACA_EXGEN+EX_CTR(r13)
> +	ld	r10,IAREA+EX_CTR(r13)
>   	mtctr	r10
>   	ld	r9,IAREA+EX_R9(r13)
>   	ld	r10,IAREA+EX_R10(r13)
Many thanks for the fix! I will test it with the RC1 tomorrow.

-- Christian

Re: PowerPC KVM-PR issue

[Christian Zigotzky]

On 14 June 2020 at 04:52 pm, Christian Zigotzky wrote:
> On 14 June 2020 at 02:53 pm, Nicholas Piggin wrote:
>> Excerpts from Christian Zigotzky's message of June 12, 2020 11:01 pm:
>>> 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 <npiggin@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 <npiggin@gmail.com>
>>>>      Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
>>>>      Link:
>>>> https://lore.kernel.org/r/20200225173541.1549955-13-npiggin@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.
>> Does this patch fix it for you?
>>
>> The CTR register reload in the KVM interrupt path used the wrong save
>> area for SLB (and NMI) interrupts.
>>
>> Fixes: 9600f261acaaa ("powerpc/64s/exception: Move KVM test to common 
>> code")
>> Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de>
>> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
>> ---
>>   arch/powerpc/kernel/exceptions-64s.S | 4 ++--
>>   1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/powerpc/kernel/exceptions-64s.S 
>> b/arch/powerpc/kernel/exceptions-64s.S
>> index e70ebb5c318c..fa080694e581 100644
>> --- a/arch/powerpc/kernel/exceptions-64s.S
>> +++ b/arch/powerpc/kernel/exceptions-64s.S
>> @@ -270,7 +270,7 @@ BEGIN_FTR_SECTION
>>   END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
>>       .endif
>>   -    ld    r10,PACA_EXGEN+EX_CTR(r13)
>> +    ld    r10,IAREA+EX_CTR(r13)
>>       mtctr    r10
>>   BEGIN_FTR_SECTION
>>       ld    r10,IAREA+EX_PPR(r13)
>> @@ -298,7 +298,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
>>         .if IKVM_SKIP
>>   89:    mtocrf    0x80,r9
>> -    ld    r10,PACA_EXGEN+EX_CTR(r13)
>> +    ld    r10,IAREA+EX_CTR(r13)
>>       mtctr    r10
>>       ld    r9,IAREA+EX_R9(r13)
>>       ld    r10,IAREA+EX_R10(r13)
> Many thanks for the fix! I will test it with the RC1 tomorrow.
>
> -- Christian

It works! :-) Thanks a lot! Screenshot: 
https://i.pinimg.com/originals/5d/5f/e5/5d5fe584db474dc88bcc641450b2a7e0.png

-- Christian

Re: PowerPC KVM-PR issue

[Christian Zigotzky]

On 15 June 2020 at 01:39 am, Christian Zigotzky wrote:
> On 14 June 2020 at 04:52 pm, Christian Zigotzky wrote:
>> On 14 June 2020 at 02:53 pm, Nicholas Piggin wrote:
>>> Excerpts from Christian Zigotzky's message of June 12, 2020 11:01 pm:
>>>> 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 <npiggin@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 <npiggin@gmail.com>
>>>>>      Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
>>>>>      Link:
>>>>> https://lore.kernel.org/r/20200225173541.1549955-13-npiggin@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 a lot of restructuring work during the kernel 5.7 development 
>>>> time in
>>>> the PowerPC area so it isn't possible to 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.
>>> Does this patch fix it for you?
>>>
>>> The CTR register reload in the KVM interrupt path used the wrong save
>>> area for SLB (and NMI) interrupts.
>>>
>>> Fixes: 9600f261acaaa ("powerpc/64s/exception: Move KVM test to 
>>> common code")
>>> Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de>
>>> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
>>> ---
>>>   arch/powerpc/kernel/exceptions-64s.S | 4 ++--
>>>   1 file changed, 2 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/arch/powerpc/kernel/exceptions-64s.S 
>>> b/arch/powerpc/kernel/exceptions-64s.S
>>> index e70ebb5c318c..fa080694e581 100644
>>> --- a/arch/powerpc/kernel/exceptions-64s.S
>>> +++ b/arch/powerpc/kernel/exceptions-64s.S
>>> @@ -270,7 +270,7 @@ BEGIN_FTR_SECTION
>>>   END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
>>>       .endif
>>>   -    ld    r10,PACA_EXGEN+EX_CTR(r13)
>>> +    ld    r10,IAREA+EX_CTR(r13)
>>>       mtctr    r10
>>>   BEGIN_FTR_SECTION
>>>       ld    r10,IAREA+EX_PPR(r13)
>>> @@ -298,7 +298,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
>>>         .if IKVM_SKIP
>>>   89:    mtocrf    0x80,r9
>>> -    ld    r10,PACA_EXGEN+EX_CTR(r13)
>>> +    ld    r10,IAREA+EX_CTR(r13)
>>>       mtctr    r10
>>>       ld    r9,IAREA+EX_R9(r13)
>>>       ld    r10,IAREA+EX_R10(r13)
>> Many thanks for the fix! I will test it with the RC1 tomorrow.
>>
>> -- Christian
>
> It works! :-) Thanks a lot! Screenshot: 
> https://i.pinimg.com/originals/5d/5f/e5/5d5fe584db474dc88bcc641450b2a7e0.png
>
> -- Christian

I also successfully tested it with Mac-on-Linux/KVM-PR today. 
Screenshot: 
https://i.pinimg.com/originals/d6/5e/3c/d65e3c694ca22996569a193dd0aabbdc.png

-- Christian

Re: PowerPC KVM-PR issue

[Christian Zigotzky]

On 15 June 2020 at 01:39 pm, Christian Zigotzky wrote:
> On 14 June 2020 at 04:52 pm, Christian Zigotzky wrote:
>> On 14 June 2020 at 02:53 pm, Nicholas Piggin wrote:
>>> Excerpts from Christian Zigotzky's message of June 12, 2020 11:01 pm:
>>>> 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 <npiggin@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 <npiggin@gmail.com>
>>>>>      Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
>>>>>      Link:
>>>>> https://lore.kernel.org/r/20200225173541.1549955-13-npiggin@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.
>>> Does this patch fix it for you?
>>>
>>> The CTR register reload in the KVM interrupt path used the wrong save
>>> area for SLB (and NMI) interrupts.
>>>
>>> Fixes: 9600f261acaaa ("powerpc/64s/exception: Move KVM test to 
>>> common code")
>>> Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de>
>>> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
>>> ---
>>>   arch/powerpc/kernel/exceptions-64s.S | 4 ++--
>>>   1 file changed, 2 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/arch/powerpc/kernel/exceptions-64s.S 
>>> b/arch/powerpc/kernel/exceptions-64s.S
>>> index e70ebb5c318c..fa080694e581 100644
>>> --- a/arch/powerpc/kernel/exceptions-64s.S
>>> +++ b/arch/powerpc/kernel/exceptions-64s.S
>>> @@ -270,7 +270,7 @@ BEGIN_FTR_SECTION
>>>   END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
>>>       .endif
>>>   -    ld    r10,PACA_EXGEN+EX_CTR(r13)
>>> +    ld    r10,IAREA+EX_CTR(r13)
>>>       mtctr    r10
>>>   BEGIN_FTR_SECTION
>>>       ld    r10,IAREA+EX_PPR(r13)
>>> @@ -298,7 +298,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
>>>         .if IKVM_SKIP
>>>   89:    mtocrf    0x80,r9
>>> -    ld    r10,PACA_EXGEN+EX_CTR(r13)
>>> +    ld    r10,IAREA+EX_CTR(r13)
>>>       mtctr    r10
>>>       ld    r9,IAREA+EX_R9(r13)
>>>       ld    r10,IAREA+EX_R10(r13)
>> Many thanks for the fix! I will test it with the RC1 tomorrow.
>>
>> -- Christian
>
> It works! :-) Thanks a lot! Screenshot: 
> https://i.pinimg.com/originals/5d/5f/e5/5d5fe584db474dc88bcc641450b2a7e0.png
>
> -- Christian

Just for info: I successfully tested KVM-PR with the stable kernel 5.7.6 
and with the RC2 of kernel 5.8 today. Thanks a lot for fixing the issue.

-- Christian