[PATCH-for-5.0?] target/ppc: Fix TCG temporary leaks in gen_slbia()

[PATCH-for-5.0?] target/ppc: Fix TCG temporary leaks in gen_slbia()

[Philippe Mathieu-Daudé]

This fixes:

  $ qemu-system-ppc64 \
  -machine pseries-4.1 -cpu power9 \
  -smp 4 -m 12G -accel tcg ...
  ...
  Quiescing Open Firmware ...
  Booting Linux via __start() @ 0x0000000002000000 ...
  Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
  Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
  Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries

[*] https://www.mail-archive.com/qemu-discuss@nongnu.org/msg05400.html

Fixes: 0418bf78fe8 ("Fix ISA v3.0 (POWER9) slbia implementation")
Reported-by: Dennis Clarke <dclarke@blastwave.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
 target/ppc/translate.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/target/ppc/translate.c b/target/ppc/translate.c
index b207fb5386..0136c7e3ff 100644
--- a/target/ppc/translate.c
+++ b/target/ppc/translate.c
@@ -5003,6 +5003,7 @@ static void gen_slbia(DisasContext *ctx)
     CHK_SV;
 
     gen_helper_slbia(cpu_env, t0);
+    tcg_temp_free_i32(t0);
 #endif /* defined(CONFIG_USER_ONLY) */
 }
 
-- 
2.21.1

Re: [PATCH-for-5.0?] target/ppc: Fix TCG temporary leaks in gen_slbia()

[Nicholas Piggin]

Excerpts from Philippe Mathieu-Daudé's message of April 17, 2020 7:07 pm:
> This fixes:
> 
>   $ qemu-system-ppc64 \
>   -machine pseries-4.1 -cpu power9 \
>   -smp 4 -m 12G -accel tcg ...
>   ...
>   Quiescing Open Firmware ...
>   Booting Linux via __start() @ 0x0000000002000000 ...
>   Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
>   Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
>   Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
> 
> [*] https://www.mail-archive.com/qemu-discuss@nongnu.org/msg05400.html
> 
> Fixes: 0418bf78fe8 ("Fix ISA v3.0 (POWER9) slbia implementation")
> Reported-by: Dennis Clarke <dclarke@blastwave.org>
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

Thank you, brown bag required. Looks like I should be testing
this stuff with --enable-debug, sorry I didn't realise it.

Thanks,
Nick

Re: [PATCH-for-5.0?] target/ppc: Fix TCG temporary leaks in gen_slbia()

[Philippe Mathieu-Daudé]

On 4/17/20 12:51 PM, Nicholas Piggin wrote:
> Excerpts from Philippe Mathieu-Daudé's message of April 17, 2020 7:07 pm:
>> This fixes:
>>
>>   $ qemu-system-ppc64 \
>>   -machine pseries-4.1 -cpu power9 \
>>   -smp 4 -m 12G -accel tcg ...
>>   ...
>>   Quiescing Open Firmware ...
>>   Booting Linux via __start() @ 0x0000000002000000 ...
>>   Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
>>   Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
>>   Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
>>
>> [*] https://www.mail-archive.com/qemu-discuss@nongnu.org/msg05400.html
>>
>> Fixes: 0418bf78fe8 ("Fix ISA v3.0 (POWER9) slbia implementation")
>> Reported-by: Dennis Clarke <dclarke@blastwave.org>
>> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> 
> Thank you, brown bag required. Looks like I should be testing
> this stuff with --enable-debug, sorry I didn't realise it.

Is that an implicit:

Reviewed-by: Nicholas Piggin <npiggin@gmail.com>

?

Re: [PATCH-for-5.0?] target/ppc: Fix TCG temporary leaks in gen_slbia()

[Cédric Le Goater]

On 4/17/20 11:07 AM, Philippe Mathieu-Daudé wrote:
> This fixes:
> 
>   $ qemu-system-ppc64 \
>   -machine pseries-4.1 -cpu power9 \
>   -smp 4 -m 12G -accel tcg ...
>   ...
>   Quiescing Open Firmware ...
>   Booting Linux via __start() @ 0x0000000002000000 ...
>   Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
>   Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
>   Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
> 
> [*] https://www.mail-archive.com/qemu-discuss@nongnu.org/msg05400.html
> 
> Fixes: 0418bf78fe8 ("Fix ISA v3.0 (POWER9) slbia implementation")
> Reported-by: Dennis Clarke <dclarke@blastwave.org>
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

Reviewed-by: Cédric Le Goater <clg@kaod.org>

Thanks,

C.

> ---
>  target/ppc/translate.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/target/ppc/translate.c b/target/ppc/translate.c
> index b207fb5386..0136c7e3ff 100644
> --- a/target/ppc/translate.c
> +++ b/target/ppc/translate.c
> @@ -5003,6 +5003,7 @@ static void gen_slbia(DisasContext *ctx)
>      CHK_SV;
>  
>      gen_helper_slbia(cpu_env, t0);
> +    tcg_temp_free_i32(t0);
>  #endif /* defined(CONFIG_USER_ONLY) */
>  }
>  
> 

Re: [PATCH-for-5.0?] target/ppc: Fix TCG temporary leaks in gen_slbia()

[Nicholas Piggin]

Excerpts from Philippe Mathieu-Daudé's message of April 17, 2020 9:00 pm:
> On 4/17/20 12:51 PM, Nicholas Piggin wrote:
>> Excerpts from Philippe Mathieu-Daudé's message of April 17, 2020 7:07 pm:
>>> This fixes:
>>>
>>>   $ qemu-system-ppc64 \
>>>   -machine pseries-4.1 -cpu power9 \
>>>   -smp 4 -m 12G -accel tcg ...
>>>   ...
>>>   Quiescing Open Firmware ...
>>>   Booting Linux via __start() @ 0x0000000002000000 ...
>>>   Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
>>>   Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
>>>   Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
>>>
>>> [*] https://www.mail-archive.com/qemu-discuss@nongnu.org/msg05400.html
>>>
>>> Fixes: 0418bf78fe8 ("Fix ISA v3.0 (POWER9) slbia implementation")
>>> Reported-by: Dennis Clarke <dclarke@blastwave.org>
>>> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
>> 
>> Thank you, brown bag required. Looks like I should be testing
>> this stuff with --enable-debug, sorry I didn't realise it.
> 
> Is that an implicit:
> 
> Reviewed-by: Nicholas Piggin <npiggin@gmail.com>

Yes sure :) If not already merged, 

Reviewed-by: Nicholas Piggin <npiggin@gmail.com>

Re: [PATCH-for-5.0?] target/ppc: Fix TCG temporary leaks in gen_slbia()

[Peter Maydell]

On Fri, 17 Apr 2020 at 10:08, Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
>
> This fixes:
>
>   $ qemu-system-ppc64 \
>   -machine pseries-4.1 -cpu power9 \
>   -smp 4 -m 12G -accel tcg ...
>   ...
>   Quiescing Open Firmware ...
>   Booting Linux via __start() @ 0x0000000002000000 ...
>   Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
>   Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
>   Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
>
> [*] https://www.mail-archive.com/qemu-discuss@nongnu.org/msg05400.html
>
> Fixes: 0418bf78fe8 ("Fix ISA v3.0 (POWER9) slbia implementation")
> Reported-by: Dennis Clarke <dclarke@blastwave.org>
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

I propose to apply this patch for 5.0 rc4 (as well as the
ppc pullreq already sent), since the iscsi bugfix means
we need an rc4 anyway. Any objections?

thanks
-- PMM

Re: [PATCH-for-5.0?] target/ppc: Fix TCG temporary leaks in gen_slbia()

[Dennis Clarke]

On 4/20/20 6:56 PM, Peter Maydell wrote:
> On Fri, 17 Apr 2020 at 10:08, Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
>>
>> This fixes:
>>
>>    $ qemu-system-ppc64 \
>>    -machine pseries-4.1 -cpu power9 \
>>    -smp 4 -m 12G -accel tcg ...
>>    ...
>>    Quiescing Open Firmware ...
>>    Booting Linux via __start() @ 0x0000000002000000 ...
>>    Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
>>    Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
>>    Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
>>
>> [*] https://www.mail-archive.com/qemu-discuss@nongnu.org/msg05400.html
>>
>> Fixes: 0418bf78fe8 ("Fix ISA v3.0 (POWER9) slbia implementation")
>> Reported-by: Dennis Clarke <dclarke@blastwave.org>
>> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> 
> I propose to apply this patch for 5.0 rc4 (as well as the
> ppc pullreq already sent), since the iscsi bugfix means
> we need an rc4 anyway. Any objections?
> 

I have been running rc3 with this patch fine for some days now.  Both 
with and without a debug enabled build wherein the performance 
difference between the two is obvious.

However, I do see warnings from 5.0.0-rc3 that worry me :

$ /usr/local/bin/qemu-system-ppc64 \
 > -machine pseries-4.1 -cpu power9 -smp 4 -m 12G -accel tcg \
 > -drive file=/home/ppc64/ppc64le.qcow2 \
 > -device virtio-net-pci,netdev=usernet \
 > -netdev user,id=usernet,hostfwd=tcp::10000-:22 \
 > -serial stdio -display none -vga none
qemu-system-ppc64: warning: TCG doesn't support requested feature, 
cap-cfpc=workaround
qemu-system-ppc64: warning: TCG doesn't support requested feature, 
cap-sbbc=workaround
qemu-system-ppc64: warning: TCG doesn't support requested feature, 
cap-ibs=workaround


SLOF **********************************************************************
QEMU Starting
  Build Date = Mar 27 2020 13:57:26
  FW Version = git-8e012d6fddb62be8
  Press "s" to enter Open Firmware.

Populating /vdevice methods
Populating /vdevice/vty@71000000
Populating /vdevice/nvram@71000001
Populating /vdevice/v-scsi@71000002
        SCSI: Looking for devices
           8000000000000000 DISK     : "QEMU     QEMU HARDDISK    2.5+"
           8200000000000000 CD-ROM   : "QEMU     QEMU CD-ROM      2.5+"
Populating /pci@800000020000000
                      00 0000 (D) : 1af4 1000    virtio [ net ]
No NVRAM common partition, re-initializing...
Scanning USB
Using default console: /vdevice/vty@71000000

   Welcome to Open Firmware

   Copyright (c) 2004, 2017 IBM Corporation All rights reserved.
   This program and the accompanying materials are made available
   under the terms of the BSD License available at
   http://www.opensource.org/licenses/bsd-license.php


Trying to load:  from: /vdevice/v-scsi@71000002/disk@8000000000000000 
...   Successfully loaded


etc etc etc

What shall I do with "TCG doesn't support requested feature, 
cap-cfpc=workaround" ??

-- 
Dennis Clarke
RISC-V/SPARC/PPC/ARM/CISC
UNIX and Linux spoken
GreyBeard and suspenders optional

Re: [PATCH-for-5.0?] target/ppc: Fix TCG temporary leaks in gen_slbia()

[David Gibson]

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On Mon, Apr 20, 2020 at 07:56:50PM +0100, Peter Maydell wrote:
> On Fri, 17 Apr 2020 at 10:08, Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
> >
> > This fixes:
> >
> >   $ qemu-system-ppc64 \
> >   -machine pseries-4.1 -cpu power9 \
> >   -smp 4 -m 12G -accel tcg ...
> >   ...
> >   Quiescing Open Firmware ...
> >   Booting Linux via __start() @ 0x0000000002000000 ...
> >   Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
> >   Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
> >   Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
> >
> > [*] https://www.mail-archive.com/qemu-discuss@nongnu.org/msg05400.html
> >
> > Fixes: 0418bf78fe8 ("Fix ISA v3.0 (POWER9) slbia implementation")
> > Reported-by: Dennis Clarke <dclarke@blastwave.org>
> > Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> 
> I propose to apply this patch for 5.0 rc4 (as well as the
> ppc pullreq already sent), since the iscsi bugfix means
> we need an rc4 anyway. Any objections?

Works for me.

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

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Re: [PATCH-for-5.0?] target/ppc: Fix TCG temporary leaks in gen_slbia()

[David Gibson]

[-- Attachment #1: Type: text/plain, Size: 2872 bytes --]

On Mon, Apr 20, 2020 at 10:53:48PM +0000, Dennis Clarke wrote:
> On 4/20/20 6:56 PM, Peter Maydell wrote:
> > On Fri, 17 Apr 2020 at 10:08, Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
> > > 
> > > This fixes:
> > > 
> > >    $ qemu-system-ppc64 \
> > >    -machine pseries-4.1 -cpu power9 \
> > >    -smp 4 -m 12G -accel tcg ...
> > >    ...
> > >    Quiescing Open Firmware ...
> > >    Booting Linux via __start() @ 0x0000000002000000 ...
> > >    Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
> > >    Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
> > >    Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
> > > 
> > > [*] https://www.mail-archive.com/qemu-discuss@nongnu.org/msg05400.html
> > > 
> > > Fixes: 0418bf78fe8 ("Fix ISA v3.0 (POWER9) slbia implementation")
> > > Reported-by: Dennis Clarke <dclarke@blastwave.org>
> > > Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> > 
> > I propose to apply this patch for 5.0 rc4 (as well as the
> > ppc pullreq already sent), since the iscsi bugfix means
> > we need an rc4 anyway. Any objections?
> > 
> 
> I have been running rc3 with this patch fine for some days now.  Both with
> and without a debug enabled build wherein the performance difference between
> the two is obvious.
> 
> However, I do see warnings from 5.0.0-rc3 that worry me :
> 
> $ /usr/local/bin/qemu-system-ppc64 \
> > -machine pseries-4.1 -cpu power9 -smp 4 -m 12G -accel tcg \
> > -drive file=/home/ppc64/ppc64le.qcow2 \
> > -device virtio-net-pci,netdev=usernet \
> > -netdev user,id=usernet,hostfwd=tcp::10000-:22 \
> > -serial stdio -display none -vga none
> qemu-system-ppc64: warning: TCG doesn't support requested feature,
> cap-cfpc=workaround
> qemu-system-ppc64: warning: TCG doesn't support requested feature,
> cap-sbbc=workaround
> qemu-system-ppc64: warning: TCG doesn't support requested feature,
> cap-ibs=workaround

These are completely unrelated to the slbia patch.

[snip]
> etc etc etc
> 
> What shall I do with "TCG doesn't support requested feature,
> cap-cfpc=workaround" ??

Ignore them, probably.  It means your TCG guest is insecure against
Spectre attacks, but it was always going to be one way or another.

You can suppress them with:
    -machine cap-cfpc=broken,cap-sbbc=broken,cap-ibs=broken

That doesn't make anything more secure, it just lets qemu know that's
what you intended, and in turn it will tell the guest that these
mitigations are not available.

These are enabled by default, because they're very important for
production KVM guests.  However, doing equivalent Spectre mitigation
for TCG is essentially infeasible.

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

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Re: [PATCH-for-5.0?] target/ppc: Fix TCG temporary leaks in gen_slbia()

[Philippe Mathieu-Daudé]

On 4/21/20 12:53 AM, Dennis Clarke wrote:
> On 4/20/20 6:56 PM, Peter Maydell wrote:
>> On Fri, 17 Apr 2020 at 10:08, Philippe Mathieu-Daudé <f4bug@amsat.org>
>> wrote:
>>>
>>> This fixes:
>>>
>>>    $ qemu-system-ppc64 \
>>>    -machine pseries-4.1 -cpu power9 \
>>>    -smp 4 -m 12G -accel tcg ...
>>>    ...
>>>    Quiescing Open Firmware ...
>>>    Booting Linux via __start() @ 0x0000000002000000 ...
>>>    Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
>>>    Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
>>>    Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
>>>
>>> [*] https://www.mail-archive.com/qemu-discuss@nongnu.org/msg05400.html
>>>
>>> Fixes: 0418bf78fe8 ("Fix ISA v3.0 (POWER9) slbia implementation")
>>> Reported-by: Dennis Clarke <dclarke@blastwave.org>
>>> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
>>
>> I propose to apply this patch for 5.0 rc4 (as well as the
>> ppc pullreq already sent), since the iscsi bugfix means
>> we need an rc4 anyway. Any objections?
>>
> 
> I have been running rc3 with this patch fine for some days now.  Both
> with and without a debug enabled build wherein the performance
> difference between the two is obvious.

Thanks for testing it! Can we use your:

Tested-by: Dennis Clarke <dclarke@blastwave.org>

tag?

> 
> However, I do see warnings from 5.0.0-rc3 that worry me :
> 
> $ /usr/local/bin/qemu-system-ppc64 \
>> -machine pseries-4.1 -cpu power9 -smp 4 -m 12G -accel tcg \
>> -drive file=/home/ppc64/ppc64le.qcow2 \
>> -device virtio-net-pci,netdev=usernet \
>> -netdev user,id=usernet,hostfwd=tcp::10000-:22 \
>> -serial stdio -display none -vga none
> qemu-system-ppc64: warning: TCG doesn't support requested feature,
> cap-cfpc=workaround
> qemu-system-ppc64: warning: TCG doesn't support requested feature,
> cap-sbbc=workaround
> qemu-system-ppc64: warning: TCG doesn't support requested feature,
> cap-ibs=workaround
> 
> 
> SLOF **********************************************************************
> QEMU Starting
>  Build Date = Mar 27 2020 13:57:26
>  FW Version = git-8e012d6fddb62be8
>  Press "s" to enter Open Firmware.
> 
> Populating /vdevice methods
> Populating /vdevice/vty@71000000
> Populating /vdevice/nvram@71000001
> Populating /vdevice/v-scsi@71000002
>        SCSI: Looking for devices
>           8000000000000000 DISK     : "QEMU     QEMU HARDDISK    2.5+"
>           8200000000000000 CD-ROM   : "QEMU     QEMU CD-ROM      2.5+"
> Populating /pci@800000020000000
>                      00 0000 (D) : 1af4 1000    virtio [ net ]
> No NVRAM common partition, re-initializing...
> Scanning USB
> Using default console: /vdevice/vty@71000000
> 
>   Welcome to Open Firmware
> 
>   Copyright (c) 2004, 2017 IBM Corporation All rights reserved.
>   This program and the accompanying materials are made available
>   under the terms of the BSD License available at
>   http://www.opensource.org/licenses/bsd-license.php
> 
> 
> Trying to load:  from: /vdevice/v-scsi@71000002/disk@8000000000000000
> ...   Successfully loaded
> 
> 
> etc etc etc
> 
> What shall I do with "TCG doesn't support requested feature,
> cap-cfpc=workaround" ??
> 

Re: [PATCH-for-5.0?] target/ppc: Fix TCG temporary leaks in gen_slbia()

[Peter Maydell]

On Tue, 21 Apr 2020 at 01:39, David Gibson <david@gibson.dropbear.id.au> wrote:
>
> On Mon, Apr 20, 2020 at 07:56:50PM +0100, Peter Maydell wrote:
> > On Fri, 17 Apr 2020 at 10:08, Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
> > >
> > > This fixes:
> > >
> > >   $ qemu-system-ppc64 \
> > >   -machine pseries-4.1 -cpu power9 \
> > >   -smp 4 -m 12G -accel tcg ...
> > >   ...
> > >   Quiescing Open Firmware ...
> > >   Booting Linux via __start() @ 0x0000000002000000 ...
> > >   Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
> > >   Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
> > >   Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
> > >
> > > [*] https://www.mail-archive.com/qemu-discuss@nongnu.org/msg05400.html
> > >
> > > Fixes: 0418bf78fe8 ("Fix ISA v3.0 (POWER9) slbia implementation")
> > > Reported-by: Dennis Clarke <dclarke@blastwave.org>
> > > Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> >
> > I propose to apply this patch for 5.0 rc4 (as well as the
> > ppc pullreq already sent), since the iscsi bugfix means
> > we need an rc4 anyway. Any objections?
>
> Works for me.


Applied to master, thanks.

-- PMM

Re: [PATCH-for-5.0?] target/ppc: Fix TCG temporary leaks in gen_slbia()

[Dennis Clarke]

On 2020-04-21 03:17, Philippe Mathieu-Daudé wrote:
> On 4/21/20 12:53 AM, Dennis Clarke wrote:
>> On 4/20/20 6:56 PM, Peter Maydell wrote:
>>> On Fri, 17 Apr 2020 at 10:08, Philippe Mathieu-Daudé <f4bug@amsat.org>
>>> wrote:
>>>>
>>>> This fixes:
>>>>
>>>>     $ qemu-system-ppc64 \
>>>>     -machine pseries-4.1 -cpu power9 \
>>>>     -smp 4 -m 12G -accel tcg ...
>>>>     ...
>>>>     Quiescing Open Firmware ...
>>>>     Booting Linux via __start() @ 0x0000000002000000 ...
>>>>     Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
>>>>     Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
>>>>     Opcode 1f 12 0f 00 (7ce003e4) leaked temporaries
>>>>
>>>> [*] https://www.mail-archive.com/qemu-discuss@nongnu.org/msg05400.html
>>>>
>>>> Fixes: 0418bf78fe8 ("Fix ISA v3.0 (POWER9) slbia implementation")
>>>> Reported-by: Dennis Clarke <dclarke@blastwave.org>
>>>> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
>>>
>>> I propose to apply this patch for 5.0 rc4 (as well as the
>>> ppc pullreq already sent), since the iscsi bugfix means
>>> we need an rc4 anyway. Any objections?
>>>
>>
>> I have been running rc3 with this patch fine for some days now.  Both
>> with and without a debug enabled build wherein the performance
>> difference between the two is obvious.
> 
> Thanks for testing it! Can we use your:
> 
> Tested-by: Dennis Clarke <dclarke@blastwave.org>
> 
> tag?


Of course.  Even "running fine by that old UNIX guy" if you want.


-- 
Dennis Clarke
RISC-V/SPARC/PPC/ARM/CISC
UNIX and Linux spoken
GreyBeard and suspenders optional