[Qemu-devel] [Bug 1774605] [NEW] PowerPC guest does not emulate L2 and L3 cache for KVM vCPUs

[Qemu-devel] [Bug 1774605] [NEW] PowerPC guest does not emulate L2 and L3 cache for KVM vCPUs

[Satheesh Rajendran]

Public bug reported:

PowerPC KVM guest does not emulate L2 and L2 caches for vCPU, it would
be good to have them enabled if not any known issues/limitation already
with PowerPC.

Host Env:
kernel: 4.17.0-rc7-00045-g0512e0134582
qemu: v2.12.0-923-gc181ddaa17-dirty
#libvirtd -V
libvirtd (libvirt) 4.4.0


Guest Kernel:
# uname -a
Linux atest-guest 4.17.0-rc7-00045-g0512e0134582 #9 SMP Fri Jun 1 02:55:50 EDT 2018 ppc64le ppc64le ppc64le GNU/Linux

Guest:
# lscpu
Architecture:        ppc64le
Byte Order:          Little Endian
CPU(s):              16
On-line CPU(s) list: 0-15
Thread(s) per core:  8
Core(s) per socket:  2
Socket(s):           1
NUMA node(s):        1
Model:               2.1 (pvr 004b 0201)
Model name:          POWER8 (architected), altivec supported
Hypervisor vendor:   KVM
Virtualization type: para
L1d cache:           64K
L1i cache:           32K
NUMA node0 CPU(s):   0-15


background: x86 enabling cpu L2 cache bydefault and L3 cache on demand for kvm guest
and claims performance improvement as vcpus can be 
benefited with lesser `vmexits due to guest send IPIs.` with L3 cache enabled, below was patch for same.

https://git.qemu.org/?p=qemu.git;a=commit;h=14c985cffa6cb177fc01a163d8bcf227c104718c

** Affects: qemu
     Importance: Undecided
         Status: New

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https://bugs.launchpad.net/bugs/1774605

Title:
  PowerPC guest does not emulate L2 and L3 cache for KVM vCPUs

Status in QEMU:
  New

Bug description:
  PowerPC KVM guest does not emulate L2 and L2 caches for vCPU, it would
  be good to have them enabled if not any known issues/limitation
  already with PowerPC.

  Host Env:
  kernel: 4.17.0-rc7-00045-g0512e0134582
  qemu: v2.12.0-923-gc181ddaa17-dirty
  #libvirtd -V
  libvirtd (libvirt) 4.4.0

  
  Guest Kernel:
  # uname -a
  Linux atest-guest 4.17.0-rc7-00045-g0512e0134582 #9 SMP Fri Jun 1 02:55:50 EDT 2018 ppc64le ppc64le ppc64le GNU/Linux

  Guest:
  # lscpu
  Architecture:        ppc64le
  Byte Order:          Little Endian
  CPU(s):              16
  On-line CPU(s) list: 0-15
  Thread(s) per core:  8
  Core(s) per socket:  2
  Socket(s):           1
  NUMA node(s):        1
  Model:               2.1 (pvr 004b 0201)
  Model name:          POWER8 (architected), altivec supported
  Hypervisor vendor:   KVM
  Virtualization type: para
  L1d cache:           64K
  L1i cache:           32K
  NUMA node0 CPU(s):   0-15


  background: x86 enabling cpu L2 cache bydefault and L3 cache on demand for kvm guest
  and claims performance improvement as vcpus can be 
  benefited with lesser `vmexits due to guest send IPIs.` with L3 cache enabled, below was patch for same.

  https://git.qemu.org/?p=qemu.git;a=commit;h=14c985cffa6cb177fc01a163d8bcf227c104718c

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[Qemu-devel] [Bug 1774605] Re: PowerPC guest does not emulate L2 and L3 cache for KVM vCPUs

[Satheesh Rajendran]

Guest xml(cpu portion):

...
   <vcpu placement='static' current='16'>32</vcpu>
  <resource>
    <partition>/machine</partition>
  </resource>
  <os>
    <type arch='ppc64le' machine='pseries-2.13'>hvm</type>
    <kernel>/home/kvmci/linux/vmlinux</kernel>
    <cmdline>root=/dev/sda2 rw console=tty0 console=ttyS0,115200 init=/sbin/init initcall_debug</cmdline>
    <boot dev='hd'/>
  </os>
  <cpu mode='host-passthrough' check='none'>
    <topology sockets='2' cores='2' threads='8'/>
  </cpu>
...


Host lscpu:
# lscpu
Architecture:         ppc64le
Byte Order:           Little Endian
CPU(s):               80
On-line CPU(s) list:  0,8,16,24,32,40,48,56,64,72
Off-line CPU(s) list: 1-7,9-15,17-23,25-31,33-39,41-47,49-55,57-63,65-71,73-79
Thread(s) per core:   1
Core(s) per socket:   5
Socket(s):            2
NUMA node(s):         2
Model:                2.1 (pvr 004b 0201)
Model name:           POWER8E (raw), altivec supported
CPU max MHz:          3690.0000
CPU min MHz:          2061.0000
L1d cache:            64K
L1i cache:            32K
L2 cache:             512K
L3 cache:             8192K
NUMA node0 CPU(s):    0,8,16,24,32
NUMA node1 CPU(s):    40,48,56,64,72

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https://bugs.launchpad.net/bugs/1774605

Title:
  PowerPC guest does not emulate L2 and L3 cache for KVM vCPUs

Status in QEMU:
  New

Bug description:
  PowerPC KVM guest does not emulate L2 and L2 caches for vCPU, it would
  be good to have them enabled if not any known issues/limitation
  already with PowerPC.

  Host Env:
  kernel: 4.17.0-rc7-00045-g0512e0134582
  qemu: v2.12.0-923-gc181ddaa17-dirty
  #libvirtd -V
  libvirtd (libvirt) 4.4.0

  
  Guest Kernel:
  # uname -a
  Linux atest-guest 4.17.0-rc7-00045-g0512e0134582 #9 SMP Fri Jun 1 02:55:50 EDT 2018 ppc64le ppc64le ppc64le GNU/Linux

  Guest:
  # lscpu
  Architecture:        ppc64le
  Byte Order:          Little Endian
  CPU(s):              16
  On-line CPU(s) list: 0-15
  Thread(s) per core:  8
  Core(s) per socket:  2
  Socket(s):           1
  NUMA node(s):        1
  Model:               2.1 (pvr 004b 0201)
  Model name:          POWER8 (architected), altivec supported
  Hypervisor vendor:   KVM
  Virtualization type: para
  L1d cache:           64K
  L1i cache:           32K
  NUMA node0 CPU(s):   0-15


  background: x86 enabling cpu L2 cache bydefault and L3 cache on demand for kvm guest
  and claims performance improvement as vcpus can be 
  benefited with lesser `vmexits due to guest send IPIs.` with L3 cache enabled, below was patch for same.

  https://git.qemu.org/?p=qemu.git;a=commit;h=14c985cffa6cb177fc01a163d8bcf227c104718c

To manage notifications about this bug go to:
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[Qemu-devel] [Bug 1774605] Re: PowerPC guest does not emulate L2 and L3 cache for KVM vCPUs

[Satheesh Rajendran]

** Description changed:

  PowerPC KVM guest does not emulate L2 and L2 caches for vCPU, it would
- be good to have them enabled if not any known issues/limitation already
- with PowerPC.
+ be good to have them emulated to guest if not any known
+ issues/limitation already with PowerPC.
  
  Host Env:
  kernel: 4.17.0-rc7-00045-g0512e0134582
  qemu: v2.12.0-923-gc181ddaa17-dirty
  #libvirtd -V
  libvirtd (libvirt) 4.4.0
- 
  
  Guest Kernel:
  # uname -a
  Linux atest-guest 4.17.0-rc7-00045-g0512e0134582 #9 SMP Fri Jun 1 02:55:50 EDT 2018 ppc64le ppc64le ppc64le GNU/Linux
  
  Guest:
  # lscpu
  Architecture:        ppc64le
  Byte Order:          Little Endian
  CPU(s):              16
  On-line CPU(s) list: 0-15
  Thread(s) per core:  8
  Core(s) per socket:  2
  Socket(s):           1
  NUMA node(s):        1
  Model:               2.1 (pvr 004b 0201)
  Model name:          POWER8 (architected), altivec supported
  Hypervisor vendor:   KVM
  Virtualization type: para
  L1d cache:           64K
  L1i cache:           32K
  NUMA node0 CPU(s):   0-15
  
- 
  background: x86 enabling cpu L2 cache bydefault and L3 cache on demand for kvm guest
- and claims performance improvement as vcpus can be 
+ and claims performance improvement as vcpus can be
  benefited with lesser `vmexits due to guest send IPIs.` with L3 cache enabled, below was patch for same.
  
  https://git.qemu.org/?p=qemu.git;a=commit;h=14c985cffa6cb177fc01a163d8bcf227c104718c

-- 
You received this bug notification because you are a member of qemu-
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https://bugs.launchpad.net/bugs/1774605

Title:
  PowerPC guest does not emulate L2 and L3 cache for KVM vCPUs

Status in QEMU:
  New

Bug description:
  PowerPC KVM guest does not emulate L2 and L2 caches for vCPU, it would
  be good to have them emulated to guest if not any known
  issues/limitation already with PowerPC.

  Host Env:
  kernel: 4.17.0-rc7-00045-g0512e0134582
  qemu: v2.12.0-923-gc181ddaa17-dirty
  #libvirtd -V
  libvirtd (libvirt) 4.4.0

  Guest Kernel:
  # uname -a
  Linux atest-guest 4.17.0-rc7-00045-g0512e0134582 #9 SMP Fri Jun 1 02:55:50 EDT 2018 ppc64le ppc64le ppc64le GNU/Linux

  Guest:
  # lscpu
  Architecture:        ppc64le
  Byte Order:          Little Endian
  CPU(s):              16
  On-line CPU(s) list: 0-15
  Thread(s) per core:  8
  Core(s) per socket:  2
  Socket(s):           1
  NUMA node(s):        1
  Model:               2.1 (pvr 004b 0201)
  Model name:          POWER8 (architected), altivec supported
  Hypervisor vendor:   KVM
  Virtualization type: para
  L1d cache:           64K
  L1i cache:           32K
  NUMA node0 CPU(s):   0-15

  background: x86 enabling cpu L2 cache bydefault and L3 cache on demand for kvm guest
  and claims performance improvement as vcpus can be
  benefited with lesser `vmexits due to guest send IPIs.` with L3 cache enabled, below was patch for same.

  https://git.qemu.org/?p=qemu.git;a=commit;h=14c985cffa6cb177fc01a163d8bcf227c104718c

To manage notifications about this bug go to:
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[Bug 1774605] Re: PowerPC guest does not emulate L2 and L3 cache for KVM vCPUs

[Thomas Huth]

** Tags added: ppc

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https://bugs.launchpad.net/bugs/1774605

Title:
  PowerPC guest does not emulate L2 and L3 cache for KVM vCPUs

Status in QEMU:
  New

Bug description:
  PowerPC KVM guest does not emulate L2 and L2 caches for vCPU, it would
  be good to have them emulated to guest if not any known
  issues/limitation already with PowerPC.

  Host Env:
  kernel: 4.17.0-rc7-00045-g0512e0134582
  qemu: v2.12.0-923-gc181ddaa17-dirty
  #libvirtd -V
  libvirtd (libvirt) 4.4.0

  Guest Kernel:
  # uname -a
  Linux atest-guest 4.17.0-rc7-00045-g0512e0134582 #9 SMP Fri Jun 1 02:55:50 EDT 2018 ppc64le ppc64le ppc64le GNU/Linux

  Guest:
  # lscpu
  Architecture:        ppc64le
  Byte Order:          Little Endian
  CPU(s):              16
  On-line CPU(s) list: 0-15
  Thread(s) per core:  8
  Core(s) per socket:  2
  Socket(s):           1
  NUMA node(s):        1
  Model:               2.1 (pvr 004b 0201)
  Model name:          POWER8 (architected), altivec supported
  Hypervisor vendor:   KVM
  Virtualization type: para
  L1d cache:           64K
  L1i cache:           32K
  NUMA node0 CPU(s):   0-15

  background: x86 enabling cpu L2 cache bydefault and L3 cache on demand for kvm guest
  and claims performance improvement as vcpus can be
  benefited with lesser `vmexits due to guest send IPIs.` with L3 cache enabled, below was patch for same.

  https://git.qemu.org/?p=qemu.git;a=commit;h=14c985cffa6cb177fc01a163d8bcf227c104718c

To manage notifications about this bug go to:
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[Bug 1774605] Re: PowerPC guest does not emulate L2 and L3 cache for KVM vCPUs

[Thomas Huth]

The QEMU project is currently considering to move its bug tracking to
another system. For this we need to know which bugs are still valid
and which could be closed already. Thus we are setting older bugs to
"Incomplete" now.

If you still think this bug report here is valid, then please switch
the state back to "New" within the next 60 days, otherwise this report
will be marked as "Expired". Or please mark it as "Fix Released" if
the problem has been solved with a newer version of QEMU already.

Thank you and sorry for the inconvenience.

** Changed in: qemu
       Status: New => Incomplete

-- 
You received this bug notification because you are a member of qemu-
devel-ml, which is subscribed to QEMU.
https://bugs.launchpad.net/bugs/1774605

Title:
  PowerPC guest does not emulate L2 and L3 cache for KVM vCPUs

Status in QEMU:
  Incomplete

Bug description:
  PowerPC KVM guest does not emulate L2 and L2 caches for vCPU, it would
  be good to have them emulated to guest if not any known
  issues/limitation already with PowerPC.

  Host Env:
  kernel: 4.17.0-rc7-00045-g0512e0134582
  qemu: v2.12.0-923-gc181ddaa17-dirty
  #libvirtd -V
  libvirtd (libvirt) 4.4.0

  Guest Kernel:
  # uname -a
  Linux atest-guest 4.17.0-rc7-00045-g0512e0134582 #9 SMP Fri Jun 1 02:55:50 EDT 2018 ppc64le ppc64le ppc64le GNU/Linux

  Guest:
  # lscpu
  Architecture:        ppc64le
  Byte Order:          Little Endian
  CPU(s):              16
  On-line CPU(s) list: 0-15
  Thread(s) per core:  8
  Core(s) per socket:  2
  Socket(s):           1
  NUMA node(s):        1
  Model:               2.1 (pvr 004b 0201)
  Model name:          POWER8 (architected), altivec supported
  Hypervisor vendor:   KVM
  Virtualization type: para
  L1d cache:           64K
  L1i cache:           32K
  NUMA node0 CPU(s):   0-15

  background: x86 enabling cpu L2 cache bydefault and L3 cache on demand for kvm guest
  and claims performance improvement as vcpus can be
  benefited with lesser `vmexits due to guest send IPIs.` with L3 cache enabled, below was patch for same.

  https://git.qemu.org/?p=qemu.git;a=commit;h=14c985cffa6cb177fc01a163d8bcf227c104718c

To manage notifications about this bug go to:
https://bugs.launchpad.net/qemu/+bug/1774605/+subscriptions

[Bug 1774605] Re: PowerPC guest does not emulate L2 and L3 cache for KVM vCPUs

[Launchpad Bug Tracker]

[Expired for QEMU because there has been no activity for 60 days.]

** Changed in: qemu
       Status: Incomplete => Expired

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You received this bug notification because you are a member of qemu-
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https://bugs.launchpad.net/bugs/1774605

Title:
  PowerPC guest does not emulate L2 and L3 cache for KVM vCPUs

Status in QEMU:
  Expired

Bug description:
  PowerPC KVM guest does not emulate L2 and L2 caches for vCPU, it would
  be good to have them emulated to guest if not any known
  issues/limitation already with PowerPC.

  Host Env:
  kernel: 4.17.0-rc7-00045-g0512e0134582
  qemu: v2.12.0-923-gc181ddaa17-dirty
  #libvirtd -V
  libvirtd (libvirt) 4.4.0

  Guest Kernel:
  # uname -a
  Linux atest-guest 4.17.0-rc7-00045-g0512e0134582 #9 SMP Fri Jun 1 02:55:50 EDT 2018 ppc64le ppc64le ppc64le GNU/Linux

  Guest:
  # lscpu
  Architecture:        ppc64le
  Byte Order:          Little Endian
  CPU(s):              16
  On-line CPU(s) list: 0-15
  Thread(s) per core:  8
  Core(s) per socket:  2
  Socket(s):           1
  NUMA node(s):        1
  Model:               2.1 (pvr 004b 0201)
  Model name:          POWER8 (architected), altivec supported
  Hypervisor vendor:   KVM
  Virtualization type: para
  L1d cache:           64K
  L1i cache:           32K
  NUMA node0 CPU(s):   0-15

  background: x86 enabling cpu L2 cache bydefault and L3 cache on demand for kvm guest
  and claims performance improvement as vcpus can be
  benefited with lesser `vmexits due to guest send IPIs.` with L3 cache enabled, below was patch for same.

  https://git.qemu.org/?p=qemu.git;a=commit;h=14c985cffa6cb177fc01a163d8bcf227c104718c

To manage notifications about this bug go to:
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