summaryrefslogtreecommitdiff
path: root/arch/powerpc/kernel
AgeCommit message (Collapse)Author
2017-05-25powerpc: Add PPC_FEATURE userspace bits for SCV and DARN instructionsNicholas Piggin
Providing "scv" support to userspace requires kernel support, so it must be advertised as independently to the base ISA 3 instruction set. The darn instruction relies on firmware enablement, so it has been decided to split this out from the core ISA 3 feature as well. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-25powerpc: Fix booting P9 hash with CONFIG_PPC_RADIX_MMU=NMichael Neuling
Currently if you disable CONFIG_PPC_RADIX_MMU you'll crash on boot on a P9. This is because we still set MMU_FTR_TYPE_RADIX via ibm,pa-features and MMU_FTR_TYPE_RADIX is what's used for code patching in much of the asm code (ie. slb_miss_realmode) This patch fixes the problem by stopping MMU_FTR_TYPE_RADIX from being set from ibm.pa-features. We may eventually end up removing the CONFIG_PPC_RADIX_MMU option completely but until then this fixes the issue. Fixes: 17a3dd2f5fc7 ("powerpc/mm/radix: Use firmware feature to enable Radix MMU") Cc: stable@vger.kernel.org # v4.7+ Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-16powerpc/kprobes: Fix handling of instruction emulation on probe re-entryNaveen N. Rao
Commit 22d8b3dec214c ("powerpc/kprobes: Emulate instructions on kprobe handler re-entry") enabled emulating instructions on kprobe re-entry, rather than single-stepping always. However, we didn't update the single stepping code to only be run if the emulation fails. Also, we missed re-enabling preemption if the instruction emulation was successful. Fix those issues. Fixes: 22d8b3dec214c ("powerpc/kprobes: Emulate instructions on kprobe handler re-entry") Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-16powerpc/powernv: Set NAPSTATELOST after recovering paca on P9 DD1Gautham R. Shenoy
Commit 17ed4c8f81da ("powerpc/powernv: Recover correct PACA on wakeup from a stop on P9 DD1") promises to set the NAPSTATELOST bit in paca after recovering the correct paca for the thread waking up from stop1 on DD1, so that the GPRs can be correctly restored on the stop exit path. However, it loads the value 1 into r3, but stores the value in r0 into NAPSTATELOST(r13). Fix this by correctly set the NAPSTATELOST bit in paca after recovering the paca on POWER9 DD1. Fixes: 17ed4c8f81da ("powerpc/powernv: Recover correct PACA on wakeup from a stop on P9 DD1") Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-15powerpc/tm: Fix FP and VMX register corruptionMichael Neuling
In commit dc3106690b20 ("powerpc: tm: Always use fp_state and vr_state to store live registers"), a section of code was removed that copied the current state to checkpointed state. That code should not have been removed. When an FP (Floating Point) unavailable is taken inside a transaction, we need to abort the transaction. This is because at the time of the tbegin, the FP state is bogus so the state stored in the checkpointed registers is incorrect. To fix this, we treclaim (to get the checkpointed GPRs) and then copy the thread_struct FP live state into the checkpointed state. We then trecheckpoint so that the FP state is correctly restored into the CPU. The copying of the FP registers from live to checkpointed is what was missing. This simplifies the logic slightly from the original patch. tm_reclaim_thread() will now always write the checkpointed FP state. Either the checkpointed FP state will be written as part of the actual treclaim (in tm.S), or it'll be a copy of the live state. Which one we use is based on MSR[FP] from userspace. Similarly for VMX. Fixes: dc3106690b20 ("powerpc: tm: Always use fp_state and vr_state to store live registers") Cc: stable@vger.kernel.org # 4.9+ Signed-off-by: Michael Neuling <mikey@neuling.org> Reviewed-by: cyrilbur@gmail.com Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-12Merge tag 'powerpc-4.12-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull more powerpc updates from Michael Ellerman: "The change to the Linux page table geometry was delayed for more testing with 16G pages, and there's the new CPU features stuff which just needed one more polish before going in. Plus a few changes from Scott which came in a bit late. And then various fixes, mostly minor. Summary highlights: - rework the Linux page table geometry to lower memory usage on 64-bit Book3S (IBM chips) using the Hash MMU. - support for a new device tree binding for discovering CPU features on future firmwares. - Freescale updates from Scott: "Includes a fix for a powerpc/next mm regression on 64e, a fix for a kernel hang on 64e when using a debugger inside a relocated kernel, a qman fix, and misc qe improvements." Thanks to: Christophe Leroy, Gavin Shan, Horia Geantă, LiuHailong, Nicholas Piggin, Roy Pledge, Scott Wood, Valentin Longchamp" * tag 'powerpc-4.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/64s: Support new device tree binding for discovering CPU features powerpc: Don't print cpu_spec->cpu_name if it's NULL of/fdt: introduce of_scan_flat_dt_subnodes and of_get_flat_dt_phandle powerpc/64s: Fix unnecessary machine check handler relocation branch powerpc/mm/book3s/64: Rework page table geometry for lower memory usage powerpc: Fix distclean with Makefile.postlink powerpc/64e: Don't place the stack beyond TASK_SIZE powerpc/powernv: Block PCI config access on BCM5718 during EEH recovery powerpc/8xx: Adding support of IRQ in MPC8xx GPIO soc/fsl/qbman: Disable IRQs for deferred QBMan work soc/fsl/qe: add EXPORT_SYMBOL for the 2 qe_tdm functions soc/fsl/qe: only apply QE_General4 workaround on affected SoCs soc/fsl/qe: round brg_freq to 1kHz granularity soc/fsl/qe: get rid of immrbar_virt_to_phys() net: ethernet: ucc_geth: fix MEM_PART_MURAM mode powerpc/64e: Fix hang when debugging programs with relocated kernel
2017-05-09powerpc/64s: Support new device tree binding for discovering CPU featuresNicholas Piggin
The ibm,powerpc-cpu-features device tree binding describes CPU features with ASCII names and extensible compatibility, privilege, and enablement metadata that allows improved flexibility and compatibility with new hardware. The interface is described in detail in ibm,powerpc-cpu-features.txt in this patch. Currently this code is not enabled by default, and there are no released firmwares that provide the binding. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-09powerpc: Don't print cpu_spec->cpu_name if it's NULLNicholas Piggin
Currently we assume that if the cpu_spec has a pvr_mask then it must also have a cpu_name. But that will change in a subsequent commit when we do CPU feature discovery via the device tree, so check explicitly if cpu_name is NULL. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-09Merge branch 'next' of ↵Michael Ellerman
git://git.kernel.org/pub/scm/linux/kernel/git/scottwood/linux into next Freescale updates from Scott: "Includes a fix for a powerpc/next mm regression on 64e, a fix for a kernel hang on 64e when using a debugger inside a relocated kernel, a qman fix, and misc qe improvements."
2017-05-09Merge branch 'kvm-ppc-next' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD The main thing here is a new implementation of the in-kernel XICS interrupt controller emulation for POWER9 machines, from Ben Herrenschmidt. POWER9 has a new interrupt controller called XIVE (eXternal Interrupt Virtualization Engine) which is able to deliver interrupts directly to guest virtual CPUs in hardware without hypervisor intervention. With this new code, the guest still sees the old XICS interface but performance is better because the XICS emulation in the host uses the XIVE directly rather than going through a XICS emulation in firmware. Conflicts: arch/powerpc/kernel/cpu_setup_power.S [cherry-picked fix] arch/powerpc/kvm/book3s_xive.c [include asm/debugfs.h]
2017-05-09powerpc/64s: Fix unnecessary machine check handler relocation branchNicholas Piggin
Similarly to commit 2563a70c3b ("powerpc/64s: Remove unnecessary relocation branch from idle handler"), the machine check handler has a BRANCH_TO from relocated to relocated code, which is unnecessary. It has also caused build errors with some toolchains: arch/powerpc/kernel/exceptions-64s.S: Assembler messages: arch/powerpc/kernel/exceptions-64s.S:395: Error: operand out of range (0xffffffffffff8280 is not between 0x0000000000000000 and 0x000000000000ffff) Fixes: 1945bc4549e5 ("powerpc/64s: Fix POWER9 machine check handler from stop state") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reported-and-tested-by : Abdul Haleem <abdhalee@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-08Merge tag 'pci-v4.12-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI updates from Bjorn Helgaas: - add framework for supporting PCIe devices in Endpoint mode (Kishon Vijay Abraham I) - use non-postable PCI config space mappings when possible (Lorenzo Pieralisi) - clean up and unify mmap of PCI BARs (David Woodhouse) - export and unify Function Level Reset support (Christoph Hellwig) - avoid FLR for Intel 82579 NICs (Sasha Neftin) - add pci_request_irq() and pci_free_irq() helpers (Christoph Hellwig) - short-circuit config access failures for disconnected devices (Keith Busch) - remove D3 sleep delay when possible (Adrian Hunter) - freeze PME scan before suspending devices (Lukas Wunner) - stop disabling MSI/MSI-X in pci_device_shutdown() (Prarit Bhargava) - disable boot interrupt quirk for ASUS M2N-LR (Stefan Assmann) - add arch-specific alignment control to improve device passthrough by avoiding multiple BARs in a page (Yongji Xie) - add sysfs sriov_drivers_autoprobe to control VF driver binding (Bodong Wang) - allow slots below PCI-to-PCIe "reverse bridges" (Bjorn Helgaas) - fix crashes when unbinding host controllers that don't support removal (Brian Norris) - add driver for MicroSemi Switchtec management interface (Logan Gunthorpe) - add driver for Faraday Technology FTPCI100 host bridge (Linus Walleij) - add i.MX7D support (Andrey Smirnov) - use generic MSI support for Aardvark (Thomas Petazzoni) - make Rockchip driver modular (Brian Norris) - advertise 128-byte Read Completion Boundary support for Rockchip (Shawn Lin) - advertise PCI_EXP_LNKSTA_SLC for Rockchip root port (Shawn Lin) - convert atomic_t to refcount_t in HV driver (Elena Reshetova) - add CPU IRQ affinity in HV driver (K. Y. Srinivasan) - fix PCI bus removal in HV driver (Long Li) - add support for ThunderX2 DMA alias topology (Jayachandran C) - add ThunderX pass2.x 2nd node MCFG quirk (Tomasz Nowicki) - add ITE 8893 bridge DMA alias quirk (Jarod Wilson) - restrict Cavium ACS quirk only to CN81xx/CN83xx/CN88xx devices (Manish Jaggi) * tag 'pci-v4.12-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (146 commits) PCI: Don't allow unbinding host controllers that aren't prepared ARM: DRA7: clockdomain: Change the CLKTRCTRL of CM_PCIE_CLKSTCTRL to SW_WKUP MAINTAINERS: Add PCI Endpoint maintainer Documentation: PCI: Add userguide for PCI endpoint test function tools: PCI: Add sample test script to invoke pcitest tools: PCI: Add a userspace tool to test PCI endpoint Documentation: misc-devices: Add Documentation for pci-endpoint-test driver misc: Add host side PCI driver for PCI test function device PCI: Add device IDs for DRA74x and DRA72x dt-bindings: PCI: dra7xx: Add DT bindings to enable unaligned access PCI: dwc: dra7xx: Workaround for errata id i870 dt-bindings: PCI: dra7xx: Add DT bindings for PCI dra7xx EP mode PCI: dwc: dra7xx: Add EP mode support PCI: dwc: dra7xx: Facilitate wrapper and MSI interrupts to be enabled independently dt-bindings: PCI: Add DT bindings for PCI designware EP mode PCI: dwc: designware: Add EP mode support Documentation: PCI: Add binding documentation for pci-test endpoint function ixgbe: Use pcie_flr() instead of duplicating it IB/hfi1: Use pcie_flr() instead of duplicating it PCI: imx6: Fix spelling mistake: "contol" -> "control" ...
2017-05-08Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge more updates from Andrew Morton: - the rest of MM - various misc things - procfs updates - lib/ updates - checkpatch updates - kdump/kexec updates - add kvmalloc helpers, use them - time helper updates for Y2038 issues. We're almost ready to remove current_fs_time() but that awaits a btrfs merge. - add tracepoints to DAX * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (114 commits) drivers/staging/ccree/ssi_hash.c: fix build with gcc-4.4.4 selftests/vm: add a test for virtual address range mapping dax: add tracepoint to dax_insert_mapping() dax: add tracepoint to dax_writeback_one() dax: add tracepoints to dax_writeback_mapping_range() dax: add tracepoints to dax_load_hole() dax: add tracepoints to dax_pfn_mkwrite() dax: add tracepoints to dax_iomap_pte_fault() mtd: nand: nandsim: convert to memalloc_noreclaim_*() treewide: convert PF_MEMALLOC manipulations to new helpers mm: introduce memalloc_noreclaim_{save,restore} mm: prevent potential recursive reclaim due to clearing PF_MEMALLOC mm/huge_memory.c: deposit a pgtable for DAX PMD faults when required mm/huge_memory.c: use zap_deposited_table() more time: delete CURRENT_TIME_SEC and CURRENT_TIME gfs2: replace CURRENT_TIME with current_time apparmorfs: replace CURRENT_TIME with current_time() lustre: replace CURRENT_TIME macro fs: ubifs: replace CURRENT_TIME_SEC with current_time fs: ufs: use ktime_get_real_ts64() for birthtime ...
2017-05-08powerpc/fadump: reuse crashkernel parameter for fadump memory reservationHari Bathini
fadump supports specifying memory to reserve for fadump's crash kernel with fadump_reserve_mem kernel parameter. This parameter currently supports passing a fixed memory size, like fadump_reserve_mem=<size> only. This patch aims to add support for other syntaxes like range-based memory size <range1>:<size1>[,<range2>:<size2>,<range3>:<size3>,...] which allows using the same parameter to boot the kernel with different system RAM sizes. As crashkernel parameter already supports the above mentioned syntaxes, this patch deprecates fadump_reserve_mem parameter and reuses crashkernel parameter instead, to specify memory for fadump's crash kernel memory reservation as well. If any offset is provided in crashkernel parameter, it will be ignored in case of fadump, as fadump reserves memory at end of RAM. Advantages using crashkernel parameter instead of fadump_reserve_mem parameter are one less kernel parameter overall, code reuse and support for multiple syntaxes to specify memory. Suggested-by: Dave Young <dyoung@redhat.com> Link: http://lkml.kernel.org/r/149035346749.6881.911095631212975718.stgit@hbathini.in.ibm.com Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com> Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Dave Young <dyoung@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08powerpc/fadump: remove dependency with CONFIG_KEXECHari Bathini
Now that crashkernel parameter parsing and vmcoreinfo related code is moved under CONFIG_CRASH_CORE instead of CONFIG_KEXEC_CORE, remove dependency with CONFIG_KEXEC for CONFIG_FA_DUMP. While here, get rid of definitions of fadump_append_elf_note() & fadump_final_note() functions to reuse similar functions compiled under CONFIG_CRASH_CORE. Link: http://lkml.kernel.org/r/149035343956.6881.1536459326017709354.stgit@hbathini.in.ibm.com Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com> Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Dave Young <dyoung@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Paolo Bonzini: "ARM: - HYP mode stub supports kexec/kdump on 32-bit - improved PMU support - virtual interrupt controller performance improvements - support for userspace virtual interrupt controller (slower, but necessary for KVM on the weird Broadcom SoCs used by the Raspberry Pi 3) MIPS: - basic support for hardware virtualization (ImgTec P5600/P6600/I6400 and Cavium Octeon III) PPC: - in-kernel acceleration for VFIO s390: - support for guests without storage keys - adapter interruption suppression x86: - usual range of nVMX improvements, notably nested EPT support for accessed and dirty bits - emulation of CPL3 CPUID faulting generic: - first part of VCPU thread request API - kvm_stat improvements" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (227 commits) kvm: nVMX: Don't validate disabled secondary controls KVM: put back #ifndef CONFIG_S390 around kvm_vcpu_kick Revert "KVM: Support vCPU-based gfn->hva cache" tools/kvm: fix top level makefile KVM: x86: don't hold kvm->lock in KVM_SET_GSI_ROUTING KVM: Documentation: remove VM mmap documentation kvm: nVMX: Remove superfluous VMX instruction fault checks KVM: x86: fix emulation of RSM and IRET instructions KVM: mark requests that need synchronization KVM: return if kvm_vcpu_wake_up() did wake up the VCPU KVM: add explicit barrier to kvm_vcpu_kick KVM: perform a wake_up in kvm_make_all_cpus_request KVM: mark requests that do not need a wakeup KVM: remove #ifndef CONFIG_S390 around kvm_vcpu_wake_up KVM: x86: always use kvm_make_request instead of set_bit KVM: add kvm_{test,clear}_request to replace {test,clear}_bit s390: kvm: Cpu model support for msa6, msa7 and msa8 KVM: x86: remove irq disablement around KVM_SET_CLOCK/KVM_GET_CLOCK kvm: better MWAIT emulation for guests KVM: x86: virtualize cpuid faulting ...
2017-05-05Merge tag 'powerpc-4.12-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Highlights include: - Larger virtual address space on 64-bit server CPUs. By default we use a 128TB virtual address space, but a process can request access to the full 512TB by passing a hint to mmap(). - Support for the new Power9 "XIVE" interrupt controller. - TLB flushing optimisations for the radix MMU on Power9. - Support for CAPI cards on Power9, using the "Coherent Accelerator Interface Architecture 2.0". - The ability to configure the mmap randomisation limits at build and runtime. - Several small fixes and cleanups to the kprobes code, as well as support for KPROBES_ON_FTRACE. - Major improvements to handling of system reset interrupts, correctly treating them as NMIs, giving them a dedicated stack and using a new hypervisor call to trigger them, all of which should aid debugging and robustness. - Many fixes and other minor enhancements. Thanks to: Alastair D'Silva, Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anshuman Khandual, Anton Blanchard, Balbir Singh, Ben Hutchings, Benjamin Herrenschmidt, Bhupesh Sharma, Chris Packham, Christian Zigotzky, Christophe Leroy, Christophe Lombard, Daniel Axtens, David Gibson, Gautham R. Shenoy, Gavin Shan, Geert Uytterhoeven, Guilherme G. Piccoli, Hamish Martin, Hari Bathini, Kees Cook, Laurent Dufour, Madhavan Srinivasan, Mahesh J Salgaonkar, Mahesh Salgaonkar, Masami Hiramatsu, Matt Brown, Matthew R. Ochs, Michael Neuling, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Pan Xinhui, Paul Mackerras, Rashmica Gupta, Russell Currey, Sukadev Bhattiprolu, Thadeu Lima de Souza Cascardo, Tobin C. Harding, Tyrel Datwyler, Uma Krishnan, Vaibhav Jain, Vipin K Parashar, Yang Shi" * tag 'powerpc-4.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (214 commits) powerpc/64s: Power9 has no LPCR[VRMASD] field so don't set it powerpc/powernv: Fix TCE kill on NVLink2 powerpc/mm/radix: Drop support for CPUs without lockless tlbie powerpc/book3s/mce: Move add_taint() later in virtual mode powerpc/sysfs: Move #ifdef CONFIG_HOTPLUG_CPU out of the function body powerpc/smp: Document irq enable/disable after migrating IRQs powerpc/mpc52xx: Don't select user-visible RTAS_PROC powerpc/powernv: Document cxl dependency on special case in pnv_eeh_reset() powerpc/eeh: Clean up and document event handling functions powerpc/eeh: Avoid use after free in eeh_handle_special_event() cxl: Mask slice error interrupts after first occurrence cxl: Route eeh events to all drivers in cxl_pci_error_detected() cxl: Force context lock during EEH flow powerpc/64: Allow CONFIG_RELOCATABLE if COMPILE_TEST powerpc/xmon: Teach xmon oops about radix vectors powerpc/mm/hash: Fix off-by-one in comment about kernel contexts ids powerpc/pseries: Enable VFIO powerpc/powernv: Fix iommu table size calculation hook for small tables powerpc/powernv: Check kzalloc() return value in pnv_pci_table_alloc powerpc: Add arch/powerpc/tools directory ...
2017-05-03powerpc/64s: Power9 has no LPCR[VRMASD] field so don't set itNicholas Piggin
Power9/ISAv3 has no VRMASD field in LPCR, we shouldn't be setting reserved bits, so don't set them on Power9. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-03powerpc/book3s/mce: Move add_taint() later in virtual modeMahesh Salgaonkar
machine_check_early() gets called in real mode. The very first time when add_taint() is called, it prints a warning which ends up calling opal call (that uses OPAL_CALL wrapper) for writing it to console. If we get a very first machine check while we are in opal we are doomed. OPAL_CALL overwrites the PACASAVEDMSR in r13 and in this case when we are done with MCE handling the original opal call will use this new MSR on it's way back to opal_return. This usually leads to unexpected behaviour or the kernel to panic. Instead move the add_taint() call later in the virtual mode where it is safe to call. This is broken with current FW level. We got lucky so far for not getting very first MCE hit while in OPAL. But easily reproducible on Mambo. Fixes: 27ea2c420cad ("powerpc: Set the correct kernel taint on machine check errors.") Cc: stable@vger.kernel.org # v4.2+ Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-03powerpc/sysfs: Move #ifdef CONFIG_HOTPLUG_CPU out of the function bodyMichael Ellerman
The entire body of unregister_cpu_online() is inside an #ifdef CONFIG_HOTPLUG_CPU block. This is ugly and means we create an empty function when hotplug is disabled for no reason. Instead move the #ifdef out of the function body and define the function to be NULL in the else case. This means we'll pass NULL to cpuhp_setup_state(), but that's fine because it accepts NULL to mean there is no teardown callback, which is exactly what we want. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-03powerpc/smp: Document irq enable/disable after migrating IRQsMichael Ellerman
This code was until recently completely undocumented and even now the comment is not very verbose. We've already had one patch sent to remove the IRQ enable/disable because it's "paradoxical and unnecessary". So document it thoroughly to save anyone else from puzzling over it. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-02Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching Pull livepatch updates from Jiri Kosina: - a per-task consistency model is being added for architectures that support reliable stack dumping (extending this, currently rather trivial set, is currently in the works). This extends the nature of the types of patches that can be applied by live patching infrastructure. The code stems from the design proposal made [1] back in November 2014. It's a hybrid of SUSE's kGraft and RH's kpatch, combining advantages of both: it uses kGraft's per-task consistency and syscall barrier switching combined with kpatch's stack trace switching. There are also a number of fallback options which make it quite flexible. Most of the heavy lifting done by Josh Poimboeuf with help from Miroslav Benes and Petr Mladek [1] https://lkml.kernel.org/r/20141107140458.GA21774@suse.cz - module load time patch optimization from Zhou Chengming - a few assorted small fixes * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching: livepatch: add missing printk newlines livepatch: Cancel transition a safe way for immediate patches livepatch: Reduce the time of finding module symbols livepatch: make klp_mutex proper part of API livepatch: allow removal of a disabled patch livepatch: add /proc/<pid>/patch_state livepatch: change to a per-task consistency model livepatch: store function sizes livepatch: use kstrtobool() in enabled_store() livepatch: move patching functions into patch.c livepatch: remove unnecessary object loaded check livepatch: separate enabled and patched states livepatch/s390: add TIF_PATCH_PENDING thread flag livepatch/s390: reorganize TIF thread flag bits livepatch/powerpc: add TIF_PATCH_PENDING thread flag livepatch/x86: add TIF_PATCH_PENDING thread flag livepatch: create temporary klp_update_patch_state() stub x86/entry: define _TIF_ALLWORK_MASK flags explicitly stacktrace/x86: add function for detecting reliable stack traces
2017-05-02Merge tag 'pstore-v4.12-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull pstore updates from Kees Cook: "This has a large internal refactoring along with several smaller fixes. - constify compression structures; Bhumika Goyal - restore powerpc dumping; Ankit Kumar - fix more bugs in the rarely exercises module unloading logic - reorganize filesystem locking to fix problems noticed by lockdep - refactor internal pstore APIs to make development and review easier: - improve error reporting - add kernel-doc structure and function comments - avoid insane argument passing by using a common record structure" * tag 'pstore-v4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (23 commits) pstore: Solve lockdep warning by moving inode locks pstore: Fix flags to enable dumps on powerpc pstore: Remove unused vmalloc.h in pmsg pstore: simplify write_user_compat() pstore: Remove write_buf() callback pstore: Replace arguments for write_buf_user() API pstore: Replace arguments for write_buf() API pstore: Replace arguments for erase() API pstore: Do not duplicate record metadata pstore: Allocate records on heap instead of stack pstore: Pass record contents instead of copying pstore: Always allocate buffer for decompression pstore: Replace arguments for write() API pstore: Replace arguments for read() API pstore: Switch pstore_mkfile to pass record pstore: Move record decompression to function pstore: Extract common arguments into structure pstore: Add kernel-doc for struct pstore_info pstore: Improve register_pstore() error reporting pstore: Avoid race in module unloading ...
2017-05-02powerpc/eeh: Clean up and document event handling functionsRussell Currey
Remove unnecessary tags in eeh_handle_normal_event(), and add function comments for eeh_handle_normal_event() and eeh_handle_special_event(). The only functional difference is that in the case of a PE reaching the maximum number of failures, rather than one message telling you of this and suggesting you reseat the device, there are two separate messages. Suggested-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Russell Currey <ruscur@russell.cc> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-02powerpc/eeh: Avoid use after free in eeh_handle_special_event()Russell Currey
eeh_handle_special_event() is called when an EEH event is detected but can't be narrowed down to a specific PE. This function looks through every PE to find one in an erroneous state, then calls the regular event handler eeh_handle_normal_event() once it knows which PE has an error. However, if eeh_handle_normal_event() found that the PE cannot possibly be recovered, it will free it, rendering the passed PE stale. This leads to a use after free in eeh_handle_special_event() as it attempts to clear the "recovering" state on the PE after eeh_handle_normal_event() returns. Thus, make sure the PE is valid when attempting to clear state in eeh_handle_special_event(). Fixes: 8a6b1bc70dbb ("powerpc/eeh: EEH core to handle special event") Cc: stable@vger.kernel.org # v3.11+ Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Russell Currey <ruscur@russell.cc> Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-01Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 asm updates from Ingo Molnar: "The main changes in this cycle were: - unwinder fixes and enhancements - improve ftrace interaction with the unwinder - optimize the code footprint of WARN() and related debugging constructs - ... plus misc updates, cleanups and fixes" * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) x86/unwind: Dump all stacks in unwind_dump() x86/unwind: Silence more entry-code related warnings x86/ftrace: Fix ebp in ftrace_regs_caller that screws up unwinder x86/unwind: Remove unused 'sp' parameter in unwind_dump() x86/unwind: Prepend hex mask value with '0x' in unwind_dump() x86/unwind: Properly zero-pad 32-bit values in unwind_dump() x86/unwind: Ensure stack pointer is aligned debug: Avoid setting BUGFLAG_WARNING twice x86/unwind: Silence entry-related warnings x86/unwind: Read stack return address in update_stack_state() x86/unwind: Move common code into update_stack_state() debug: Fix __bug_table[] in arch linker scripts debug: Add _ONCE() logic to report_bug() x86/debug: Define BUG() again for !CONFIG_BUG x86/debug: Implement __WARN() using UD0 x86/ftrace: Use Makefile logic instead of #ifdef for compiling ftrace_*.o x86/ftrace: Add -mfentry support to x86_32 with DYNAMIC_FTRACE set x86/ftrace: Clean up ftrace_regs_caller x86/ftrace: Add stack frame pointer to ftrace_caller x86/ftrace: Move the ftrace specific code out of entry_32.S ...
2017-05-01Merge branch 'sched-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "The main changes in this cycle were: - another round of rq-clock handling debugging, robustization and fixes - PELT accounting improvements - CPU hotplug related ->cpus_allowed affinity handling fixes all around the tree - ... plus misc fixes, cleanups and updates" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (35 commits) sched/x86: Update reschedule warning text crypto: N2 - Replace racy task affinity logic cpufreq/sparc-us2e: Replace racy task affinity logic cpufreq/sparc-us3: Replace racy task affinity logic cpufreq/sh: Replace racy task affinity logic cpufreq/ia64: Replace racy task affinity logic ACPI/processor: Replace racy task affinity logic ACPI/processor: Fix error handling in __acpi_processor_start() sparc/sysfs: Replace racy task affinity logic powerpc/smp: Replace open coded task affinity logic ia64/sn/hwperf: Replace racy task affinity logic ia64/salinfo: Replace racy task affinity logic workqueue: Provide work_on_cpu_safe() ia64/topology: Remove cpus_allowed manipulation sched/fair: Move the PELT constants into a generated header sched/fair: Increase PELT accuracy for small tasks sched/fair: Fix comments sched/Documentation: Add 'sched-pelt' tool sched/fair: Fix corner case in __accumulate_sum() sched/core: Remove 'task' parameter and rename tsk_restore_flags() to current_restore_flags() ...
2017-05-01Merge branch 'timers-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer updates from Thomas Gleixner: "The timer departement delivers: - more year 2038 rework - a massive rework of the arm achitected timer - preparatory patches to allow NTP correction of clock event devices to avoid early expiry - the usual pile of fixes and enhancements all over the place" * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (91 commits) timer/sysclt: Restrict timer migration sysctl values to 0 and 1 arm64/arch_timer: Mark errata handlers as __maybe_unused Clocksource/mips-gic: Remove redundant non devicetree init MIPS/Malta: Probe gic-timer via devicetree clocksource: Use GENMASK_ULL in definition of CLOCKSOURCE_MASK acpi/arm64: Add SBSA Generic Watchdog support in GTDT driver clocksource: arm_arch_timer: add GTDT support for memory-mapped timer acpi/arm64: Add memory-mapped timer support in GTDT driver clocksource: arm_arch_timer: simplify ACPI support code. acpi/arm64: Add GTDT table parse driver clocksource: arm_arch_timer: split MMIO timer probing. clocksource: arm_arch_timer: add structs to describe MMIO timer clocksource: arm_arch_timer: move arch_timer_needs_of_probing into DT init call clocksource: arm_arch_timer: refactor arch_timer_needs_probing clocksource: arm_arch_timer: split dt-only rate handling x86/uv/time: Set ->min_delta_ticks and ->max_delta_ticks unicore32/time: Set ->min_delta_ticks and ->max_delta_ticks um/time: Set ->min_delta_ticks and ->max_delta_ticks tile/time: Set ->min_delta_ticks and ->max_delta_ticks score/time: Set ->min_delta_ticks and ->max_delta_ticks ...
2017-04-30powerpc/64e: Fix hang when debugging programs with relocated kernelLiuHailong
Debug interrupts can be taken during interrupt entry, since interrupt entry does not automatically turn them off. The kernel will check whether the faulting instruction is between [interrupt_base_book3e, __end_interrupts], and if so clear MSR[DE] and return. However, when the kernel is built with CONFIG_RELOCATABLE, it can't use LOAD_REG_IMMEDIATE(r14,interrupt_base_book3e) and LOAD_REG_IMMEDIATE(r15,__end_interrupts), as they ignore relocation. Thus, if the kernel is actually running at a different address than it was built at, the address comparison will fail, and the exception entry code will hang at kernel_dbg_exc. r2(toc) is also not usable here, as r2 still holds data from the interrupted context, so LOAD_REG_ADDR() doesn't work either. So we use the *name@got* to get the EV of two labels directly. Test programs test.c shows as follows: int main(int argc, char *argv[]) { if (access("/proc/sys/kernel/perf_event_paranoid", F_OK) == -1) printf("Kernel doesn't have perf_event support\n"); } Steps to reproduce the bug, for example: 1) ./gdb ./test 2) (gdb) b access 3) (gdb) r 4) (gdb) s Signed-off-by: Liu Hailong <liu.hailong6@zte.com.cn> Signed-off-by: Jiang Xuexin <jiang.xuexin@zte.com.cn> Reviewed-by: Jiang Biao <jiang.biao2@zte.com.cn> Reviewed-by: Liu Song <liu.song11@zte.com.cn> Reviewed-by: Huang Jian <huang.jian@zte.com.cn> [scottwood: cleaned up commit message, and specified bad behavior as a hang rather than an oops to correspond to mainline kernel behavior] Fixes: 1cb6e0649248 ("powerpc/book3e: support CONFIG_RELOCATABLE") Cc: <stable@vger.kernel.org> # 4.4.x- Signed-off-by: Scott Wood <oss@buserror.net>
2017-04-28Merge branch 'pci/resource-mmap' into nextBjorn Helgaas
* pci/resource-mmap: ia64: Use generic pci_mmap_resource_range() ia64: Remove redundant checks for WC in pci_mmap_page_range() ia64: Remove redundant valid_mmap_phys_addr_range() from pci_mmap_page_range() PCI: Add I/O BAR support to generic pci_mmap_resource_range() x86/PCI: Use generic pci_mmap_resource_range() unicore32/PCI: Use generic pci_mmap_resource_range() sh/PCI: Use generic pci_mmap_resource_range() parisc: Use generic pci_mmap_resource_range() mn10300/PCI: Use generic pci_mmap_resource_range() MIPS: PCI: Use generic pci_mmap_resource_range() cris/PCI: Use generic pci_mmap_resource_range() ARM/PCI: Use generic pci_mmap_resource_range() PCI: Add pci_mmap_resource_range() and use it for ARM64 PCI: Add BAR index argument to pci_mmap_page_range() PCI: Use BAR index in sysfs attr->private instead of resource pointer PCI: Add arch_can_pci_mmap_io() on architectures which can mmap() I/O space PCI: Move multiple declarations of pci_mmap_page_range() to <linux/pci.h> PCI: Add arch_can_pci_mmap_wc() macro xtensa/PCI: Do not mmap PCI BARs to userspace as write-through PCI: Only allow WC mmap on prefetchable resources PCI: Fix another sanity check bug in /proc/pci mmap PCI: Fix pci_mmap_fits() for HAVE_PCI_RESOURCE_TO_USER platforms
2017-04-28powerpc: Add struct smp_ops_t.cause_nmi_ipi operationNicholas Piggin
Have the NMI IPI code use this op when the platform defines it. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-28powerpc: Add NMI IPI infrastructureNicholas Piggin
Add a simple NMI IPI system that handles concurrency and reentrancy. The platform does not have to implement a true non-maskable interrupt, the default is to simply use the debugger break IPI message. This has now been co-opted for a general IPI message, and users (debugger and crash) have been reimplemented on top of the NMI system. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Incorporate incremental fixes from Nick] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-28powerpc: Mark system reset as an NMI with nmi_enter/exit()Nicholas Piggin
System reset is a non-maskable interrupt from Linux's point of view (occurs under local_irq_disable()), so it should use nmi_enter/exit. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-28powerpc/64s: Dedicated system reset interrupt stackNicholas Piggin
The system reset interrupt is used for crash/debug situations, so it is desirable to have as little impact on the normal state of the system as possible. Currently it uses the current kernel stack to process the exception. This stores into the stack which may be involved with the crash. The stack pointer may be corrupted, or it may have overflowed. Avoid or minimise these problems by creating a dedicated NMI stack for the system reset interrupt to use. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-28powerpc/64s: Disallow system reset vs system reset reentrancyNicholas Piggin
In preparation for using a dedicated stack for system reset interrupts, prevent a nested system reset from recovering, in order to simplify code that is called in crash/debug path. This allows a system reset interrupt to just use the base stack pointer. Keep an in_nmi nesting counter similarly to the in_mce counter. Consider the interrrupt non-recoverable if it is taken inside another system reset. Interrupt nesting could be allowed similarly to MCE, but system reset is a special case that's not for normal operation, so simplicity wins until there is requirement for nested system reset interrupts. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-28powerpc/64s: Fix system reset vs general interrupt reentrancyNicholas Piggin
The system reset interrupt can occur when MSR_EE=0, and it currently uses the PACA_EXGEN save area. Some PACA_EXGEN interrupts have a window where MSR_RI=1 and MSR_EE=0 when the save area is still in use. A system reset interrupt in this window can lead to undetected corruption when the save area gets overwritten. This patch introduces PACA_EXNMI save area for system reset exceptions, which closes this corruption window. It's also helpful to retain the EXGEN state for debugging situations, even if not considering the recoverability aspect. This patch also moves the PACA_EXMC area down to a less frequently used part of the paca with the new save area. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-28powerpc/64s: Exception macro for stack frame and initial register saveNicholas Piggin
This code is common to a few exceptions, and another user will be added. This causes a trivial change to generated code: - 604: std r9,416(r1) - 608: mfspr r11,314 - 60c: std r11,368(r1) - 610: mfspr r12,315 + 604: mfspr r11,314 + 608: mfspr r12,315 + 60c: std r9,416(r1) + 610: std r11,368(r1) machine_check_powernv_early could also use this, but that requires non trivial changes to generated code, so that's for another patch. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-28powerpc/64s: Add exception macro that does not enable RINicholas Piggin
Subsequent patches will add more non-RI variant exceptions, so create a macro for it rather than open-code it. This does not change generated instructions. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-28Merge branch 'topic/ppc-kvm' into nextMichael Ellerman
Merge the topic branch we were sharing with kvm-ppc, Paul has also merged it.
2017-04-28Merge remote-tracking branch 'remotes/powerpc/topic/xive' into kvm-ppc-nextPaul Mackerras
This merges in the powerpc topic/xive branch to bring in the code for the in-kernel XICS interrupt controller emulation to use the new XIVE (eXternal Interrupt Virtualization Engine) hardware in the POWER9 chip directly, rather than via a XICS emulation in firmware. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-04-27pstore: Fix flags to enable dumps on powerpcAnkit Kumar
After commit c950fd6f201a kernel registers pstore write based on flag set. Pstore write for powerpc is broken as flags(PSTORE_FLAGS_DMESG) is not set for powerpc architecture. On panic, kernel doesn't write message to /fs/pstore/dmesg*(Entry doesn't gets created at all). This patch enables pstore write for powerpc architecture by setting PSTORE_FLAGS_DMESG flag. Fixes: c950fd6f201a ("pstore: Split pstore fragile flags") Cc: stable@vger.kernel.org # v4.9+ Signed-off-by: Ankit Kumar <ankit@linux.vnet.ibm.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2017-04-27powerpc/ftrace/64: Split further based on -mprofile-kernelNaveen N. Rao
Split ftrace_64.S further retaining the core ftrace 64-bit aspects in ftrace_64.S and moving ftrace_caller() and ftrace_graph_caller() into separate files based on -mprofile-kernel. The livepatch routines are all now contained within the mprofile file. Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-27powerpc: Split ftrace bits into a separate fileNaveen N. Rao
entry_*.S now includes a lot more than just kernel entry/exit code. As a first step at cleaning this up, let's split out the ftrace bits into separate files. Also move all related tracing code into a new trace/ subdirectory. No functional changes. Suggested-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-27KVM: PPC: Book3S HV: Native usage of the XIVE interrupt controllerBenjamin Herrenschmidt
This patch makes KVM capable of using the XIVE interrupt controller to provide the standard PAPR "XICS" style hypercalls. It is necessary for proper operations when the host uses XIVE natively. This has been lightly tested on an actual system, including PCI pass-through with a TG3 device. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [mpe: Cleanup pr_xxx(), unsplit pr_xxx() strings, etc., fix build failures by adding KVM_XIVE which depends on KVM_XICS and XIVE, and adding empty stubs for the kvm_xive_xxx() routines, fixup subject, integrate fixes from Paul for building PR=y HV=n] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-26powerpc/64s: Revert setting of LPCR[LPES] on POWER9Nicholas Piggin
The XIVE enablement patches included a change to set the LPES (Logical Partitioning Environment Selector) bit (bit # 3) in LPCR (Logical Partitioning Control Register) on POWER9 hosts. This bit sets external interrupts to guest delivery mode, which uses SRR0/1. The host's EE interrupt handler is written to expect HSRR0/1 (for earlier CPUs). This should be fine because XIVE is configured not to deliver EEs to the host (Hypervisor Virtulization Interrupt is used instead) so the EE handler should never be executed. However a bug in interrupt controller code, hardware, or odd configuration of a simulator could result in the host getting an EE incorrectly. Keeping the EE delivery mode matching the host EE handler prevents strange crashes due to using the wrong exception registers. KVM will configure the LPCR to set LPES prior to running a guest so that EEs are delivered to the guest using SRR0/1. Fixes: 08a1e650cc ("powerpc: Fixup LPCR:PECE and HEIC setting on POWER9") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Massage change log to avoid referring to LPES0 which is now renamed LPES] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-25powerpc/sysfs: Fix reference leak of cpu device_nodes present at bootTyrel Datwyler
For CPUs present at boot each logical CPU acquires a reference to the associated device node of the core. This happens in register_cpu() which is called by topology_init(). The result of this is that we end up with a reference held by each thread of the core. However, these references are never freed if the CPU core is DLPAR removed. This patch fixes the reference leaks by acquiring and releasing the references in the CPU hotplug callbacks un/register_cpu_online(). With this patch symmetric reference counting is observed with both CPUs present at boot, and those DLPAR added after boot. Fixes: f86e4718f24b ("driver/core: cpu: initialize of_node in cpu's device struture") Cc: stable@vger.kernel.org # v3.12+ Signed-off-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-25Merge branch 'topic/kprobes' into nextMichael Ellerman
Although most of these kprobes patches are powerpc specific, there's a couple that touch generic code (with Acks). At the moment there's one conflict with acme's tree, but it's not too bad. Still just in case some other conflicts show up, we've put these in a topic branch so another tree could merge some or all of it if necessary.
2017-04-24powerpc/kprobes: Prefer ftrace when probing function entryNaveen N. Rao
KPROBES_ON_FTRACE avoids much of the overhead of regular kprobes as it eliminates the need for a trap, as well as the need to emulate or single-step instructions. Though OPTPROBES provides us with similar performance, we have limited optprobes trampoline slots. As such, when asked to probe at a function entry, default to using the ftrace infrastructure. With: # cd /sys/kernel/debug/tracing # echo 'p _do_fork' > kprobe_events before patch: # cat ../kprobes/list c0000000000daf08 k _do_fork+0x8 [DISABLED] c000000000044fc0 k kretprobe_trampoline+0x0 [OPTIMIZED] and after patch: # cat ../kprobes/list c0000000000d074c k _do_fork+0xc [DISABLED][FTRACE] c0000000000412b0 k kretprobe_trampoline+0x0 [OPTIMIZED] Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-24powerpc: Introduce a new helper to obtain function entry pointsNaveen N. Rao
kprobe_lookup_name() is specific to the kprobe subsystem and may not always return the function entry point (in a subsequent patch for KPROBES_ON_FTRACE). For looking up function entry points, introduce a separate helper and use it in optprobes.c Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-24powerpc/kprobes: Add support for KPROBES_ON_FTRACENaveen N. Rao
Allow kprobes to be placed on ftrace _mcount() call sites. This optimization avoids the use of a trap, by riding on ftrace infrastructure. This depends on HAVE_DYNAMIC_FTRACE_WITH_REGS which depends on MPROFILE_KERNEL, which is only currently enabled on powerpc64le with newer toolchains. Based on the x86 code by Masami. Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>