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 <address@hidden>
>> 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/address@hidden/msg05400.html
>>>
>>> Fixes: 0418bf78fe8 ("Fix ISA v3.0 (POWER9) slbia implementation")
>>> Reported-by: Dennis Clarke <address@hidden>
>>> Signed-off-by: Philippe Mathieu-Daudé <address@hidden>
>>
>> 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 <address@hidden>

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" ??
>