linux.git/arch/powerpc/platforms/pseries/Kconfig, branch vsnprintf

powerpc/perf: Add perf interface to expose vpa counters

2024-11-19T03:11:06+00:00

To support performance measurement for KVM on PowerVM(KoP)
feature, PowerVM hypervisor has added couple of new software
counters in Virtual Process Area(VPA) of the partition.

Commit e1f288d2f9c69 ("KVM: PPC: Book3S HV nestedv2: Add
support for reading VPA counters for pseries guests")
have updated the paca fields with corresponding changes.

Proposed perf interface is to expose these new software
counters for monitoring of context switch latencies and
runtime aggregate. Perf interface driver is called
"vpa_pmu" and it has dependency on KVM and perf, hence
added new config called "VPA_PMU" which depends on
"CONFIG_KVM_BOOK3S_64_HV" and "CONFIG_HV_PERF_CTRS".
Since, kvm and kvm_host are currently compiled as built-in
modules, this perf interface takes the same path and
registered as a module.

vpa_pmu perf interface needs access to some of the kvm
functions and structures like kvmhv_get_l2_counters_status(),
hence kvm_book3s_64.h and kvm_ppc.h are included.
Below are the events added to monitor KoP:

  vpa_pmu/l1_to_l2_lat/
  vpa_pmu/l2_to_l1_lat/
  vpa_pmu/l2_runtime_agg/

and vpa_pmu driver supports only per-cpu monitoring with this patch.
Example usage:

[command]# perf stat -e vpa_pmu/l1_to_l2_lat/ -a -I 1000
     1.001017682            727,200      vpa_pmu/l1_to_l2_lat/
     2.003540491          1,118,824      vpa_pmu/l1_to_l2_lat/
     3.005699458          1,919,726      vpa_pmu/l1_to_l2_lat/
     4.007827011          2,364,630      vpa_pmu/l1_to_l2_lat/

Signed-off-by: Kajol Jain 
Co-developed-by: Madhavan Srinivasan 
Signed-off-by: Madhavan Srinivasan 
Signed-off-by: Michael Ellerman 
Link: https://patch.msgid.link/20241118114114.208964-1-kjain@linux.ibm.com

powerpc/pseries: PLPKS SED Opal keystore support

2023-10-17T15:10:06+00:00

Define operations for SED Opal to read/write keys
from POWER LPAR Platform KeyStore(PLPKS). This allows
non-volatile storage of SED Opal keys.

Signed-off-by: Greg Joyce 
Reviewed-by: Jonathan Derrick 
Link: https://lore.kernel.org/r/20231004201957.1451669-4-gjoyce@linux.vnet.ibm.com
Signed-off-by: Jens Axboe

powerc/mm: try VMA lock-based page fault handling first

2023-04-06T03:03:02+00:00

Attempt VMA lock-based page fault handling first, and fall back to the
existing mmap_lock-based handling if that fails.  Copied from "x86/mm: try
VMA lock-based page fault handling first"

[ldufour@linux.ibm.com: powerpc/mm: fix mmap_lock bad unlock]
  Link: https://lkml.kernel.org/r/20230306154244.17560-1-ldufour@linux.ibm.com
  Link: https://lore.kernel.org/linux-mm/842502FB-F99C-417C-9648-A37D0ECDC9CE@linux.ibm.com
Link: https://lkml.kernel.org/r/20230227173632.3292573-32-surenb@google.com
Signed-off-by: Laurent Dufour 
Signed-off-by: Suren Baghdasaryan 
Cc: Sachin Sant 
Signed-off-by: Andrew Morton

powerpc/pseries: RTAS work area requires GENERIC_ALLOCATOR

2023-03-14T12:03:36+00:00

The RTAS work area allocator uses code that is built by
GENERIC_ALLOCATOR, so the PSERIES Kconfig should select the
required Kconfig symbol to fix multiple build errors.

powerpc64-linux-ld: arch/powerpc/platforms/pseries/rtas-work-area.o: in function `.rtas_work_area_allocator_init':
rtas-work-area.c:(.init.text+0x288): undefined reference to `.gen_pool_create'
powerpc64-linux-ld: rtas-work-area.c:(.init.text+0x2dc): undefined reference to `.gen_pool_set_algo'
powerpc64-linux-ld: rtas-work-area.c:(.init.text+0x310): undefined reference to `.gen_pool_add_owner'
powerpc64-linux-ld: rtas-work-area.c:(.init.text+0x43c): undefined reference to `.gen_pool_destroy'
powerpc64-linux-ld: arch/powerpc/platforms/pseries/rtas-work-area.o:(.toc+0x0): undefined reference to `gen_pool_first_fit_order_align'
powerpc64-linux-ld: arch/powerpc/platforms/pseries/rtas-work-area.o: in function `.__rtas_work_area_alloc':
rtas-work-area.c:(.ref.text+0x14c): undefined reference to `.gen_pool_alloc_algo_owner'
powerpc64-linux-ld: rtas-work-area.c:(.ref.text+0x238): undefined reference to `.gen_pool_alloc_algo_owner'
powerpc64-linux-ld: arch/powerpc/platforms/pseries/rtas-work-area.o: in function `.rtas_work_area_free':
rtas-work-area.c:(.ref.text+0x44c): undefined reference to `.gen_pool_free_owner'

Fixes: 43033bc62d34 ("powerpc/pseries: add RTAS work area allocator")
Signed-off-by: Randy Dunlap 
Reviewed-by: Nathan Lynch 
Signed-off-by: Michael Ellerman 
Link: https://msgid.link/20230223070116.660-2-rdunlap@infradead.org

powerpc/pseries: Implement secvars for dynamic secure boot

2023-02-13T11:34:33+00:00

The pseries platform can support dynamic secure boot (i.e. secure boot
using user-defined keys) using variables contained with the PowerVM LPAR
Platform KeyStore (PLPKS).  Using the powerpc secvar API, expose the
relevant variables for pseries dynamic secure boot through the existing
secvar filesystem layout.

The relevant variables for dynamic secure boot are signed in the
keystore, and can only be modified using the H_PKS_SIGNED_UPDATE hcall.
Object labels in the keystore are encoded using ucs2 format.  With our
fixed variable names we don't have to care about encoding outside of the
necessary byte padding.

When a user writes to a variable, the first 8 bytes of data must contain
the signed update flags as defined by the hypervisor.

When a user reads a variable, the first 4 bytes of data contain the
policies defined for the object.

Limitations exist due to the underlying implementation of sysfs binary
attributes, as is the case for the OPAL secvar implementation -
partial writes are unsupported and writes cannot be larger than PAGE_SIZE.
(Even when using bin_attributes, which can be larger than a single page,
sysfs only gives us one page's worth of write buffer at a time, and the
hypervisor does not expose an interface for partial writes.)

Co-developed-by: Nayna Jain 
Signed-off-by: Nayna Jain 
Co-developed-by: Andrew Donnellan 
Signed-off-by: Andrew Donnellan 
Signed-off-by: Russell Currey 
[mpe: Add NLS dependency to fix build errors, squash fix from ajd]
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20230210080401.345462-25-ajd@linux.ibm.com

powerpc/pseries: Turn PSERIES_PLPKS into a hidden option

2023-02-12T11:12:38+00:00

It seems a bit unnecessary for the PLPKS code to have a user-visible
config option when it doesn't do anything on its own, and there's existing
options for enabling Secure Boot-related features.

It should be enabled by PPC_SECURE_BOOT, which will eventually be what
uses PLPKS to populate keyrings.

However, we can't get of the separate option completely, because it will
also be used for SED Opal purposes.

Change PSERIES_PLPKS into a hidden option, which is selected by
PPC_SECURE_BOOT.

Signed-off-by: Andrew Donnellan 
Signed-off-by: Russell Currey 
Reviewed-by: Stefan Berger 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20230210080401.345462-21-ajd@linux.ibm.com

powerpc/pseries: Implement CONFIG_PARAVIRT_TIME_ACCOUNTING

2022-09-05T04:14:02+00:00

CONFIG_VIRT_CPU_ACCOUNTING_GEN under pseries does not provide stolen
time accounting unless CONFIG_PARAVIRT_TIME_ACCOUNTING is enabled.
Implement this using the VPA accumulated wait counters.

Note this will not work on current KVM hosts because KVM does not
implement the VPA dispatch counters (yet). It could be implemented
with the dispatch trace log as it is for VIRT_CPU_ACCOUNTING_NATIVE,
but that is not necessary for the more limited accounting provided
by PARAVIRT_TIME_ACCOUNTING, and it is more expensive, complex, and
has downsides like potential log wrap.

From Shrikanth:

  [...] it was tested on Power10 [PowerVM] Shared LPAR. system has two
  LPAR. we will call first one LPAR1 and second one as LPAR2. Test was
  carried out in SMT=1. Similar observation was seen in SMT=8 as well.

  LPAR config header from each LPAR is below. LPAR1 is twice as big as
  LPAR2. Since Both are sharing the same underlying hardware, work
  stealing will happen when both the LPAR's are contending for the same
  resource.

  LPAR1:
  type=Shared mode=Uncapped smt=Off lcpu=40 cpus=40 ent=20.00
  LPAR2:
  type=Shared mode=Uncapped smt=Off lcpu=20 cpus=40 ent=10.00

  mpstat was used to check for the utilization. stress-ng has been used
  as the workload. Few cases are tested. when the both LPAR are idle
  there is no steal time. when LPAR1 starts running at 100% which
  consumes all of the physical resource, steal time starts to get
  accounted.  With LPAR1 running at 100% and LPAR2 starts running, steal
  time starts increasing. This is as expected. When the LPAR2 Load is
  increased further, steal time increases further.

  Case 1: 0% LPAR1; 0% LPAR2
   %usr  %nice   %sys %iowait  %irq  %soft %steal %guest %gnice  %idle
   0.00   0.00   0.05   0.00   0.00   0.00   0.00   0.00   0.00  99.95

  Case 2: 100% LPAR1; 0% LPAR2
   %usr  %nice   %sys %iowait  %irq  %soft %steal %guest %gnice  %idle
  97.68   0.00   0.00   0.00   0.00   0.00   2.32   0.00   0.00   0.00

  Case 3: 100% LPAR1; 50% LPAR2
   %usr  %nice   %sys %iowait  %irq  %soft %steal %guest %gnice  %idle
  86.34   0.00   0.10   0.00   0.00   0.03  13.54   0.00   0.00   0.00

  Case 4: 100% LPAR1; 100% LPAR2
   %usr  %nice   %sys %iowait  %irq  %soft %steal %guest %gnice  %idle
  78.54   0.00   0.07   0.00   0.00   0.02  21.36   0.00   0.00   0.00

  Case 5: 50% LPAR1; 100% LPAR2
   %usr  %nice   %sys %iowait  %irq  %soft %steal %guest %gnice  %idle
  49.37   0.00   0.00   0.00   0.00   0.00   1.17   0.00   0.00  49.47

  Patch is accounting for the steal time and basic tests are holding
  good.

Signed-off-by: Nicholas Piggin 
Tested-by: Shrikanth Hegde 
[mpe: Add SPDX tag to new paravirt_api_clock.h]
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220902085316.2071519-3-npiggin@gmail.com

Merge tag 'powerpc-6.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2022-08-06T23:38:17+00:00

Pull powerpc updates from Michael Ellerman:

 - Add support for syscall stack randomization

 - Add support for atomic operations to the 32 & 64-bit BPF JIT

 - Full support for KASAN on 64-bit Book3E

 - Add a watchdog driver for the new PowerVM hypervisor watchdog

 - Add a number of new selftests for the Power10 PMU support

 - Add a driver for the PowerVM Platform KeyStore

 - Increase the NMI watchdog timeout during live partition migration, to
   avoid timeouts due to increased memory access latency

 - Add support for using the 'linux,pci-domain' device tree property for
   PCI domain assignment

 - Many other small features and fixes

Thanks to Alexey Kardashevskiy, Andy Shevchenko, Arnd Bergmann, Athira
Rajeev, Bagas Sanjaya, Christophe Leroy, Erhard Furtner, Fabiano Rosas,
Greg Kroah-Hartman, Greg Kurz, Haowen Bai, Hari Bathini, Jason A.
Donenfeld, Jason Wang, Jiang Jian, Joel Stanley, Juerg Haefliger, Kajol
Jain, Kees Cook, Laurent Dufour, Madhavan Srinivasan, Masahiro Yamada,
Maxime Bizon, Miaoqian Lin, Murilo Opsfelder Araújo, Nathan Lynch,
Naveen N.  Rao, Nayna Jain, Nicholas Piggin, Ning Qiang, Pali Rohár,
Petr Mladek, Rashmica Gupta, Sachin Sant, Scott Cheloha, Segher
Boessenkool, Stephen Rothwell, Uwe Kleine-König, Wolfram Sang, Xiu
Jianfeng, and Zhouyi Zhou.

* tag 'powerpc-6.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (191 commits)
  powerpc/64e: Fix kexec build error
  EDAC/ppc_4xx: Include required of_irq header directly
  powerpc/pci: Fix PHB numbering when using opal-phbid
  powerpc/64: Init jump labels before parse_early_param()
  selftests/powerpc: Avoid GCC 12 uninitialised variable warning
  powerpc/cell/axon_msi: Fix refcount leak in setup_msi_msg_address
  powerpc/xive: Fix refcount leak in xive_get_max_prio
  powerpc/spufs: Fix refcount leak in spufs_init_isolated_loader
  powerpc/perf: Include caps feature for power10 DD1 version
  powerpc: add support for syscall stack randomization
  powerpc: Move system_call_exception() to syscall.c
  powerpc/powernv: rename remaining rng powernv_ functions to pnv_
  powerpc/powernv/kvm: Use darn for H_RANDOM on Power9
  powerpc/powernv: Avoid crashing if rng is NULL
  selftests/powerpc: Fix matrix multiply assist test
  powerpc/signal: Update comment for clarity
  powerpc: make facility_unavailable_exception 64s
  powerpc/platforms/83xx/suspend: Remove write-only global variable
  powerpc/platforms/83xx/suspend: Prevent unloading the driver
  powerpc/platforms/83xx/suspend: Reorder to get rid of a forward declaration
  ...

powerpc/pseries: define driver for Platform KeyStore

2022-07-28T06:22:13+00:00

PowerVM provides an isolated Platform Keystore(PKS) storage allocation
for each LPAR with individually managed access controls to store
sensitive information securely. It provides a new set of hypervisor
calls for Linux kernel to access PKS storage.

Define POWER LPAR Platform KeyStore(PLPKS) driver using H_CALL interface
to access PKS storage.

Signed-off-by: Nayna Jain 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220723113048.521744-2-nayna@linux.ibm.com

random: remove CONFIG_ARCH_RANDOM

2022-07-18T13:03:37+00:00

When RDRAND was introduced, there was much discussion on whether it
should be trusted and how the kernel should handle that. Initially, two
mechanisms cropped up, CONFIG_ARCH_RANDOM, a compile time switch, and
"nordrand", a boot-time switch.

Later the thinking evolved. With a properly designed RNG, using RDRAND
values alone won't harm anything, even if the outputs are malicious.
Rather, the issue is whether those values are being *trusted* to be good
or not. And so a new set of options were introduced as the real
ones that people use -- CONFIG_RANDOM_TRUST_CPU and "random.trust_cpu".
With these options, RDRAND is used, but it's not always credited. So in
the worst case, it does nothing, and in the best case, maybe it helps.

Along the way, CONFIG_ARCH_RANDOM's meaning got sort of pulled into the
center and became something certain platforms force-select.

The old options don't really help with much, and it's a bit odd to have
special handling for these instructions when the kernel can deal fine
with the existence or untrusted existence or broken existence or
non-existence of that CPU capability.

Simplify the situation by removing CONFIG_ARCH_RANDOM and using the
ordinary asm-generic fallback pattern instead, keeping the two options
that are actually used. For now it leaves "nordrand" for now, as the
removal of that will take a different route.

Acked-by: Michael Ellerman 
Acked-by: Catalin Marinas 
Acked-by: Borislav Petkov 
Acked-by: Heiko Carstens 
Acked-by: Greg Kroah-Hartman 
Signed-off-by: Jason A. Donenfeld