linux-dev/arch/powerpc/platforms/pseries/Kconfig, branch master

powerpc/pseries: Implement CONFIG_PARAVIRT_TIME_ACCOUNTING

2022-09-05T04:14:02Z

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

2022-08-06T23:38:17Z

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

2022-07-28T06:22:13Z

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

2022-07-18T13:03:37Z

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

powerpc/pseries: Stop selecting PPC_HASH_MMU_NATIVE

2021-12-02T11:57:23Z

The pseries platform does not use the native hash code but the PAPR virtualised hash interfaces, so remove PPC_HASH_MMU_NATIVE. This requires moving tlbiel code from hash_native.c to hash_utils.c. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20211201144153.2456614-4-npiggin@gmail.com

powerpc: Rename PPC_NATIVE to PPC_HASH_MMU_NATIVE

2021-12-02T11:57:22Z

PPC_NATIVE now only controls the native HPT code, so rename it to be more descriptive. Restrict it to Book3S only. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20211201144153.2456614-3-npiggin@gmail.com

powerpc/pseries: delete scanlog

2021-11-25T00:25:33Z

Remove the pseries scanlog driver. This code supports functions from Power4-era servers that are not present on targets currently supported by arch/powerpc. System manuals from this time have this description: Scan Dump data is a set of chip data that the service processor gathers after a system malfunction. It consists of chip scan rings, chip trace arrays, and Scan COM (SCOM) registers. This data is stored in the scan-log partition of the system’s Nonvolatile Random Access Memory (NVRAM). PowerVM partition firmware development doesn't recognize the associated function call or property, and they don't see any references to them in their codebase. It seems to have been specific to non-virtualized pseries. References: Historical Linux commit from February 2003 (interesting to note this seems to be the source of non-GPL exports for rtas_call etc): https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git/commit/?id=f92e361842d5251e50562b09664082dcbd0548bb IntelliStation and pSeries docs which refer to the feature: http://ps-2.retropc.se/basil.holloway/ALL%20PDF/380635.pdf http://ps-2.kev009.com/rs6000/manuals/p/p615-6C3-6E3/6C3_and_6E3_Users_Guide_SA38-0629.pdf Signed-off-by: Nathan Lynch Reviewed-by: Tyrel Datwyler Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210920173203.1800475-1-nathanl@linux.ibm.com

powerpc/pseries/svm: Add a powerpc version of cc_platform_has()

2021-10-04T09:46:33Z

Introduce a powerpc version of the cc_platform_has() function. This will be used to replace the powerpc mem_encrypt_active() implementation, so the implementation will initially only support the CC_ATTR_MEM_ENCRYPT attribute. Signed-off-by: Tom Lendacky Signed-off-by: Borislav Petkov Acked-by: Michael Ellerman Link: https://lkml.kernel.org/r/20210928191009.32551-5-bp@alien8.de

powerpc/pseries: Implement paravirt qspinlocks for SPLPAR

2020-07-26T14:01:29Z

This implements the generic paravirt qspinlocks using H_PROD and H_CONFER to kick and wait. This uses an un-directed yield to any CPU rather than the directed yield to a pre-empted lock holder that paravirtualised simple spinlocks use, that requires no kick hcall. This is something that could be investigated and improved in future. Performance results can be found in the commit which added queued spinlocks. Signed-off-by: Nicholas Piggin Acked-by: Peter Zijlstra (Intel) Acked-by: Waiman Long Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200724131423.1362108-5-npiggin@gmail.com

powerpc/pseries: Remove redundant select of PPC_DOORBELL

2020-01-06T05:25:29Z

Commit d4e58e5928f8 ("powerpc/powernv: Enable POWER8 doorbell IPIs") added a select of PPC_DOORBELL to PPC_PSERIES, but it already had a select of PPC_DOORBELL. One is enough. Reported-by: Jason A. Donenfeld Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20191219125840.32592-1-mpe@ellerman.id.au