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2021-01-15Merge tag 'for-linus-5.11-rc4-tag' of ↵Linus Torvalds1-0/+4
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: - A series to fix a regression when running as a fully virtualized guest on an old Xen hypervisor not supporting PV interrupt callbacks for HVM guests. - A patch to add support to query Xen resource sizes (setting was possible already) from user mode. * tag 'for-linus-5.11-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: x86/xen: Fix xen_hvm_smp_init() when vector callback not available x86/xen: Don't register Xen IPIs when they aren't going to be used x86/xen: Add xen_no_vector_callback option to test PCI INTX delivery xen: Set platform PCI device INTX affinity to CPU0 xen: Fix event channel callback via INTX/GSI xen/privcmd: allow fetching resource sizes
2021-01-13x86/xen: Add xen_no_vector_callback option to test PCI INTX deliveryDavid Woodhouse1-0/+4
It's useful to be able to test non-vector event channel delivery, to make sure Linux will work properly on older Xen which doesn't have it. It's also useful for those working on Xen and Xen-compatible hypervisors, because there are guest kernels still in active use which use PCI INTX even when vector delivery is available. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20210106153958.584169-4-dwmw2@infradead.org Signed-off-by: Juergen Gross <jgross@suse.com>
2021-01-07Documentation/admin-guide: kernel-parameters: hyphenate comma-separatedRandy Dunlap1-6/+6
Hyphenate "comma separated" when it is used as a compound adjective. hyphenated. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Link: https://lore.kernel.org/r/20210101040831.4148-1-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-12-20Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-0/+10
Pull KVM updates from Paolo Bonzini: "Much x86 work was pushed out to 5.12, but ARM more than made up for it. ARM: - PSCI relay at EL2 when "protected KVM" is enabled - New exception injection code - Simplification of AArch32 system register handling - Fix PMU accesses when no PMU is enabled - Expose CSV3 on non-Meltdown hosts - Cache hierarchy discovery fixes - PV steal-time cleanups - Allow function pointers at EL2 - Various host EL2 entry cleanups - Simplification of the EL2 vector allocation s390: - memcg accouting for s390 specific parts of kvm and gmap - selftest for diag318 - new kvm_stat for when async_pf falls back to sync x86: - Tracepoints for the new pagetable code from 5.10 - Catch VFIO and KVM irqfd events before userspace - Reporting dirty pages to userspace with a ring buffer - SEV-ES host support - Nested VMX support for wait-for-SIPI activity state - New feature flag (AVX512 FP16) - New system ioctl to report Hyper-V-compatible paravirtualization features Generic: - Selftest improvements" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (171 commits) KVM: SVM: fix 32-bit compilation KVM: SVM: Add AP_JUMP_TABLE support in prep for AP booting KVM: SVM: Provide support to launch and run an SEV-ES guest KVM: SVM: Provide an updated VMRUN invocation for SEV-ES guests KVM: SVM: Provide support for SEV-ES vCPU loading KVM: SVM: Provide support for SEV-ES vCPU creation/loading KVM: SVM: Update ASID allocation to support SEV-ES guests KVM: SVM: Set the encryption mask for the SVM host save area KVM: SVM: Add NMI support for an SEV-ES guest KVM: SVM: Guest FPU state save/restore not needed for SEV-ES guest KVM: SVM: Do not report support for SMM for an SEV-ES guest KVM: x86: Update __get_sregs() / __set_sregs() to support SEV-ES KVM: SVM: Add support for CR8 write traps for an SEV-ES guest KVM: SVM: Add support for CR4 write traps for an SEV-ES guest KVM: SVM: Add support for CR0 write traps for an SEV-ES guest KVM: SVM: Add support for EFER write traps for an SEV-ES guest KVM: SVM: Support string IO operations for an SEV-ES guest KVM: SVM: Support MMIO for an SEV-ES guest KVM: SVM: Create trace events for VMGEXIT MSR protocol processing KVM: SVM: Create trace events for VMGEXIT processing ...
2020-12-16Merge tag 'arm-soc-drivers-5.11' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc Pull ARM SoC driver updates from Arnd Bergmann: "There are a couple of subsystems maintained by other people that merge their drivers through the SoC tree, those changes include: - The SCMI firmware framework gains support for sensor notifications and for controlling voltage domains. - A large update for the Tegra memory controller driver, integrating it better with the interconnect framework - The memory controller subsystem gains support for Mediatek MT8192 - The reset controller framework gains support for sharing pulsed resets For Soc specific drivers in drivers/soc, the main changes are - The Allwinner/sunxi MBUS gets a rework for the way it handles dma_map_ops and offsets between physical and dma address spaces. - An errata fix plus some cleanups for Freescale Layerscape SoCs - A cleanup for renesas drivers regarding MMIO accesses. - New SoC specific drivers for Mediatek MT8192 and MT8183 power domains - New SoC specific drivers for Aspeed AST2600 LPC bus control and SoC identification. - Core Power Domain support for Qualcomm MSM8916, MSM8939, SDM660 and SDX55. - A rework of the TI AM33xx 'genpd' power domain support to use information from DT instead of platform data - Support for TI AM64x SoCs - Allow building some Amlogic drivers as modules instead of built-in Finally, there are numerous cleanups and smaller bug fixes for Mediatek, Tegra, Samsung, Qualcomm, TI OMAP, Amlogic, Rockchips, Renesas, and Xilinx SoCs" * tag 'arm-soc-drivers-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (222 commits) soc: mediatek: mmsys: Specify HAS_IOMEM dependency for MTK_MMSYS firmware: xilinx: Properly align function parameter firmware: xilinx: Add a blank line after function declaration firmware: xilinx: Remove additional newline firmware: xilinx: Fix kernel-doc warnings firmware: xlnx-zynqmp: fix compilation warning soc: xilinx: vcu: add missing register NUM_CORE soc: xilinx: vcu: use vcu-settings syscon registers dt-bindings: soc: xlnx: extract xlnx, vcu-settings to separate binding soc: xilinx: vcu: drop useless success message clk: samsung: mark PM functions as __maybe_unused soc: samsung: exynos-chipid: initialize later - with arch_initcall soc: samsung: exynos-chipid: order list of SoCs by name memory: jz4780_nemc: Fix potential NULL dereference in jz4780_nemc_probe() memory: ti-emif-sram: only build for ARMv7 memory: tegra30: Support interconnect framework memory: tegra20: Support hardware versioning and clean up OPP table initialization dt-bindings: memory: tegra20-emc: Document opp-supported-hw property soc: rockchip: io-domain: Fix error return code in rockchip_iodomain_probe() reset-controller: ti: force the write operation when assert or deassert ...
2020-12-16Merge tag 'iommu-updates-v5.11' of ↵Linus Torvalds1-5/+0
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull IOMMU updates from Will Deacon: "There's a good mixture of improvements to the core code and driver changes across the board. One thing worth pointing out is that this includes a quirk to work around behaviour in the i915 driver (see 65f746e8285f ("iommu: Add quirk for Intel graphic devices in map_sg")), which otherwise interacts badly with the conversion of the intel IOMMU driver over to the DMA-IOMMU APU but has being fixed properly in the DRM tree. We'll revert the quirk later this cycle once we've confirmed that things don't fall apart without it. Summary: - IOVA allocation optimisations and removal of unused code - Introduction of DOMAIN_ATTR_IO_PGTABLE_CFG for parameterising the page-table of an IOMMU domain - Support for changing the default domain type in sysfs - Optimisation to the way in which identity-mapped regions are created - Driver updates: * Arm SMMU updates, including continued work on Shared Virtual Memory * Tegra SMMU updates, including support for PCI devices * Intel VT-D updates, including conversion to the IOMMU-DMA API - Cleanup, kerneldoc and minor refactoring" * tag 'iommu-updates-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (50 commits) iommu/amd: Add sanity check for interrupt remapping table length macros dma-iommu: remove __iommu_dma_mmap iommu/io-pgtable: Remove tlb_flush_leaf iommu: Stop exporting free_iova_mem() iommu: Stop exporting alloc_iova_mem() iommu: Delete split_and_remove_iova() iommu/io-pgtable-arm: Remove unused 'level' parameter from iopte_type() macro iommu: Defer the early return in arm_(v7s/lpae)_map iommu: Improve the performance for direct_mapping iommu: avoid taking iova_rbtree_lock twice iommu/vt-d: Avoid GFP_ATOMIC where it is not needed iommu/vt-d: Remove set but not used variable iommu: return error code when it can't get group iommu: Fix htmldocs warnings in sysfs-kernel-iommu_groups iommu: arm-smmu-impl: Add a space before open parenthesis iommu: arm-smmu-impl: Use table to list QCOM implementations iommu/arm-smmu: Move non-strict mode to use io_pgtable_domain_attr iommu/arm-smmu: Add support for pagetable config domain attribute iommu: Document usage of "/sys/kernel/iommu_groups/<grp_id>/type" file iommu: Take lock before reading iommu group default domain type ...
2020-12-15Merge tag 'usb-5.11-rc1' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb Pull USB / Thunderbolt updates from Greg KH: "Here is the big USB and thunderbolt pull request for 5.11-rc1. Nothing major in here, just the grind of constant development to support new hardware and fix old issues: - thunderbolt updates for new USB4 hardware - cdns3 major driver updates - lots of typec updates and additions as more hardware is available - usb serial driver updates and fixes - other tiny USB driver updates All have been in linux-next with no reported issues" * tag 'usb-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (172 commits) usb: phy: convert comma to semicolon usb: ucsi: convert comma to semicolon usb: typec: tcpm: convert comma to semicolon usb: typec: tcpm: Update vbus_vsafe0v on init usb: typec: tcpci: Enable bleed discharge when auto discharge is enabled usb: typec: Add class for plug alt mode device USB: typec: tcpci: Add Bleed discharge to POWER_CONTROL definition USB: typec: tcpm: Add a 30ms room for tPSSourceOn in PR_SWAP USB: typec: tcpm: Fix PR_SWAP error handling USB: typec: tcpm: Hard Reset after not receiving a Request USB: gadget: f_fs: remove likely/unlikely usb: gadget: f_fs: Re-use SS descriptors for SuperSpeedPlus USB: gadget: f_midi: setup SuperSpeed Plus descriptors USB: gadget: f_acm: add support for SuperSpeed Plus USB: gadget: f_rndis: fix bitrate for SuperSpeed and above usb: typec: intel_pmc_mux: Configure cable generation value for USB4 MAINTAINERS: Add myself as a reviewer for CADENCE USB3 DRD IP DRIVER usb: chipidea: ci_hdrc_imx: Use of_device_get_match_data() usb: chipidea: usbmisc_imx: Use of_device_get_match_data() usb: cdns3: fix NULL pointer dereference on no platform data ...
2020-12-14Merge tag 'docs-5.11' of git://git.lwn.net/linuxLinus Torvalds1-1/+1
Pull documentation updates from Jonathan Corbet: "A much quieter cycle for documentation (happily), with, one hopes, the bulk of the churn behind us. Significant stuff in this pull includes: - A set of new Chinese translations - Italian translation updates - A mechanism from Mauro to automatically format Documentation/features for the built docs - Automatic cross references without explicit :ref: markup - A new reset-controller document - An extensive new document on reporting problems from Thorsten That last patch also adds the CC-BY-4.0 license to LICENSES/dual; there was some discussion on this, but we seem to have consensus and an ack from Greg for that addition" * tag 'docs-5.11' of git://git.lwn.net/linux: (50 commits) docs: fix broken cross reference in translations/zh_CN docs: Note that sphinx 1.7 will be required soon docs: update requirements to install six module docs: reporting-issues: move 'outdated, need help' note to proper place docs: Update documentation to reflect what TAINT_CPU_OUT_OF_SPEC means docs: add a reset controller chapter to the driver API docs docs: make reporting-bugs.rst obsolete docs: Add a new text describing how to report bugs LICENSES: Add the CC-BY-4.0 license Documentation: fix multiple typos found in the admin-guide subdirectory Documentation: fix typos found in admin-guide subdirectory kernel-doc: Fix example in Nested structs/unions docs: clean up sysctl/kernel: titles, version docs: trace: fix event state structure name docs: nios2: add missing ReST file scripts: get_feat.pl: reduce table width for all features output scripts: get_feat.pl: change the group by order scripts: get_feat.pl: make complete table more coincise scripts: kernel-doc: fix parsing function-like typedefs Documentation: fix typos found in process, dev-tools, and doc-guide subdirectories ...
2020-12-14Merge tag 'x86_sgx_for_v5.11' of ↵Linus Torvalds1-0/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 SGC support from Borislav Petkov: "Intel Software Guard eXtensions enablement. This has been long in the making, we were one revision number short of 42. :) Intel SGX is new hardware functionality that can be used by applications to populate protected regions of user code and data called enclaves. Once activated, the new hardware protects enclave code and data from outside access and modification. Enclaves provide a place to store secrets and process data with those secrets. SGX has been used, for example, to decrypt video without exposing the decryption keys to nosy debuggers that might be used to subvert DRM. Software has generally been rewritten specifically to run in enclaves, but there are also projects that try to run limited unmodified software in enclaves. Most of the functionality is concentrated into arch/x86/kernel/cpu/sgx/ except the addition of a new mprotect() hook to control enclave page permissions and support for vDSO exceptions fixup which will is used by SGX enclaves. All this work by Sean Christopherson, Jarkko Sakkinen and many others" * tag 'x86_sgx_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits) x86/sgx: Return -EINVAL on a zero length buffer in sgx_ioc_enclave_add_pages() x86/sgx: Fix a typo in kernel-doc markup x86/sgx: Fix sgx_ioc_enclave_provision() kernel-doc comment x86/sgx: Return -ERESTARTSYS in sgx_ioc_enclave_add_pages() selftests/sgx: Use a statically generated 3072-bit RSA key x86/sgx: Clarify 'laundry_list' locking x86/sgx: Update MAINTAINERS Documentation/x86: Document SGX kernel architecture x86/sgx: Add ptrace() support for the SGX driver x86/sgx: Add a page reclaimer selftests/x86: Add a selftest for SGX x86/vdso: Implement a vDSO for Intel SGX enclave call x86/traps: Attempt to fixup exceptions in vDSO before signaling x86/fault: Add a helper function to sanitize error code x86/vdso: Add support for exception fixup in vDSO functions x86/sgx: Add SGX_IOC_ENCLAVE_PROVISION x86/sgx: Add SGX_IOC_ENCLAVE_INIT x86/sgx: Add SGX_IOC_ENCLAVE_ADD_PAGES x86/sgx: Add SGX_IOC_ENCLAVE_CREATE x86/sgx: Add an SGX misc driver interface ...
2020-12-09USB: UAS: introduce a quirk to set no_write_sameOliver Neukum1-0/+1
UAS does not share the pessimistic assumption storage is making that devices cannot deal with WRITE_SAME. A few devices supported by UAS, are reported to not deal well with WRITE_SAME. Those need a quirk. Add it to the device that needs it. Reported-by: David C. Partridge <david.partridge@perdrix.co.uk> Signed-off-by: Oliver Neukum <oneukum@suse.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20201209152639.9195-1-oneukum@suse.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-04KVM: arm64: Add kvm-arm.mode early kernel parameterDavid Brazdil1-0/+10
Add an early parameter that allows users to select the mode of operation for KVM/arm64. For now, the only supported value is "protected". By passing this flag users opt into the hypervisor placing additional restrictions on the host kernel. These allow the hypervisor to spawn guests whose state is kept private from the host. Restrictions will include stage-2 address translation to prevent host from accessing guest memory, filtering its SMC calls, etc. Without this parameter, the default behaviour remains selecting VHE/nVHE based on hardware support and CONFIG_ARM64_VHE. Signed-off-by: David Brazdil <dbrazdil@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20201202184122.26046-2-dbrazdil@google.com
2020-11-30Documentation/admin-guide: mark memmap parameter is supported by a few ↵Barry Song1-1/+1
architectures early_param memmap is only implemented on X86, MIPS and XTENSA. To avoid wasting users’ time on trying this on platform like ARM, mark it clearly. Signed-off-by: Barry Song <song.bao.hua@hisilicon.com> Reviewed-by: Mike Rapoport <rppt@linux.ibm.com> Link: https://lore.kernel.org/r/20201128195121.2556-1-song.bao.hua@hisilicon.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-11-25iommu/vt-d: Cleanup after converting to dma-iommu opsLu Baolu1-5/+0
Some cleanups after converting the driver to use dma-iommu ops. - Remove nobounce option; - Cleanup and simplify the path in domain mapping. Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Tested-by: Logan Gunthorpe <logang@deltatee.com> Link: https://lore.kernel.org/r/20201124082057.2614359-8-baolu.lu@linux.intel.com Signed-off-by: Will Deacon <will@kernel.org>
2020-11-19powerpc/64s: flush L1D after user accessesNicholas Piggin1-0/+4
IBM Power9 processors can speculatively operate on data in the L1 cache before it has been completely validated, via a way-prediction mechanism. It is not possible for an attacker to determine the contents of impermissible memory using this method, since these systems implement a combination of hardware and software security measures to prevent scenarios where protected data could be leaked. However these measures don't address the scenario where an attacker induces the operating system to speculatively execute instructions using data that the attacker controls. This can be used for example to speculatively bypass "kernel user access prevention" techniques, as discovered by Anthony Steinhauser of Google's Safeside Project. This is not an attack by itself, but there is a possibility it could be used in conjunction with side-channels or other weaknesses in the privileged code to construct an attack. This issue can be mitigated by flushing the L1 cache between privilege boundaries of concern. This patch flushes the L1 cache after user accesses. This is part of the fix for CVE-2020-4788. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2020-11-19powerpc/64s: flush L1D on kernel entryNicholas Piggin1-0/+3
IBM Power9 processors can speculatively operate on data in the L1 cache before it has been completely validated, via a way-prediction mechanism. It is not possible for an attacker to determine the contents of impermissible memory using this method, since these systems implement a combination of hardware and software security measures to prevent scenarios where protected data could be leaked. However these measures don't address the scenario where an attacker induces the operating system to speculatively execute instructions using data that the attacker controls. This can be used for example to speculatively bypass "kernel user access prevention" techniques, as discovered by Anthony Steinhauser of Google's Safeside Project. This is not an attack by itself, but there is a possibility it could be used in conjunction with side-channels or other weaknesses in the privileged code to construct an attack. This issue can be mitigated by flushing the L1 cache between privilege boundaries of concern. This patch flushes the L1 cache on kernel entry. This is part of the fix for CVE-2020-4788. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2020-11-17x86/cpu/intel: Add a nosgx kernel parameterJarkko Sakkinen1-0/+2
Add a kernel parameter to disable SGX kernel support and document it. [ bp: Massage. ] Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com> Acked-by: Jethro Beekman <jethro@fortanix.com> Tested-by: Sean Christopherson <sean.j.christopherson@intel.com> Link: https://lkml.kernel.org/r/20201112220135.165028-9-jarkko@kernel.org
2020-10-31Documentation: Update paths of Samsung S3C machine filesKrzysztof Kozlowski1-1/+1
Documentation references Samsung S3C24xx and S3C64xx machine files in multiple places but the files were traveling around the kernel multiple times. Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Link: https://lore.kernel.org/r/20200911143343.498-1-krzk@kernel.org
2020-10-25Merge tag 'for-linus-5.10b-rc1c-tag' of ↵Linus Torvalds1-0/+7
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull more xen updates from Juergen Gross: - a series for the Xen pv block drivers adding module parameters for better control of resource usge - a cleanup series for the Xen event driver * tag 'for-linus-5.10b-rc1c-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: Documentation: add xen.fifo_events kernel parameter description xen/events: unmask a fifo event channel only if it was masked xen/events: only register debug interrupt for 2-level events xen/events: make struct irq_info private to events_base.c xen: remove no longer used functions xen-blkfront: Apply changed parameter name to the document xen-blkfront: add a parameter for disabling of persistent grants xen-blkback: add a parameter for disabling of persistent grants
2020-10-23Documentation: add xen.fifo_events kernel parameter descriptionJuergen Gross1-0/+7
The kernel boot parameter xen.fifo_events isn't listed in Documentation/admin-guide/kernel-parameters.txt. Add it. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Link: https://lore.kernel.org/r/20201022094907.28560-6-jgross@suse.com Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-10-20Merge tag 'for-linus-5.10b-rc1b-tag' of ↵Linus Torvalds1-0/+8
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull more xen updates from Juergen Gross: - A single patch to fix the Xen security issue XSA-331 (malicious guests can DoS dom0 by triggering NULL-pointer dereferences or access to stale data). - A larger series to fix the Xen security issue XSA-332 (malicious guests can DoS dom0 by sending events at high frequency leading to dom0's vcpus being busy in IRQ handling for elongated times). * tag 'for-linus-5.10b-rc1b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/events: block rogue events for some time xen/events: defer eoi in case of excessive number of events xen/events: use a common cpu hotplug hook for event channels xen/events: switch user event channels to lateeoi model xen/pciback: use lateeoi irq binding xen/pvcallsback: use lateeoi irq binding xen/scsiback: use lateeoi irq binding xen/netback: use lateeoi irq binding xen/blkback: use lateeoi irq binding xen/events: add a new "late EOI" evtchn framework xen/events: fix race in evtchn_fifo_unmask() xen/events: add a proper barrier to 2-level uevent unmasking xen/events: avoid removing an event channel while handling it
2020-10-20xen/events: defer eoi in case of excessive number of eventsJuergen Gross1-0/+8
In case rogue guests are sending events at high frequency it might happen that xen_evtchn_do_upcall() won't stop processing events in dom0. As this is done in irq handling a crash might be the result. In order to avoid that, delay further inter-domain events after some time in xen_evtchn_do_upcall() by forcing eoi processing into a worker on the same cpu, thus inhibiting new events coming in. The time after which eoi processing is to be delayed is configurable via a new module parameter "event_loop_timeout" which specifies the maximum event loop time in jiffies (default: 2, the value was chosen after some tests showing that a value of 2 was the lowest with an only slight drop of dom0 network throughput while multiple guests performed an event storm). How long eoi processing will be delayed can be specified via another parameter "event_eoi_delay" (again in jiffies, default 10, again the value was chosen after testing with different delay values). This is part of XSA-332. Cc: stable@vger.kernel.org Reported-by: Julien Grall <julien@xen.org> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Reviewed-by: Wei Liu <wl@xen.org>
2020-10-18Merge tag 'core-rcu-2020-10-12' of ↵Linus Torvalds1-18/+135
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU changes from Ingo Molnar: - Debugging for smp_call_function() - RT raw/non-raw lock ordering fixes - Strict grace periods for KASAN - New smp_call_function() torture test - Torture-test updates - Documentation updates - Miscellaneous fixes [ This doesn't actually pull the tag - I've dropped the last merge from the RCU branch due to questions about the series. - Linus ] * tag 'core-rcu-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (77 commits) smp: Make symbol 'csd_bug_count' static kernel/smp: Provide CSD lock timeout diagnostics smp: Add source and destination CPUs to __call_single_data rcu: Shrink each possible cpu krcp rcu/segcblist: Prevent useless GP start if no CBs to accelerate torture: Add gdb support rcutorture: Allow pointer leaks to test diagnostic code rcutorture: Hoist OOM registry up one level refperf: Avoid null pointer dereference when buf fails to allocate rcutorture: Properly synchronize with OOM notifier rcutorture: Properly set rcu_fwds for OOM handling torture: Add kvm.sh --help and update help message rcutorture: Add CONFIG_PROVE_RCU_LIST to TREE05 torture: Update initrd documentation rcutorture: Replace HTTP links with HTTPS ones locktorture: Make function torture_percpu_rwsem_init() static torture: document --allcpus argument added to the kvm.sh script rcutorture: Output number of elapsed grace periods rcutorture: Remove KCSAN stubs rcu: Remove unused "cpu" parameter from rcu_report_qs_rdp() ...
2020-10-16Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-0/+1
Merge more updates from Andrew Morton: "155 patches. Subsystems affected by this patch series: mm (dax, debug, thp, readahead, page-poison, util, memory-hotplug, zram, cleanups), misc, core-kernel, get_maintainer, MAINTAINERS, lib, bitops, checkpatch, binfmt, ramfs, autofs, nilfs, rapidio, panic, relay, kgdb, ubsan, romfs, and fault-injection" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (155 commits) lib, uaccess: add failure injection to usercopy functions lib, include/linux: add usercopy failure capability ROMFS: support inode blocks calculation ubsan: introduce CONFIG_UBSAN_LOCAL_BOUNDS for Clang sched.h: drop in_ubsan field when UBSAN is in trap mode scripts/gdb/tasks: add headers and improve spacing format scripts/gdb/proc: add struct mount & struct super_block addr in lx-mounts command kernel/relay.c: drop unneeded initialization panic: dump registers on panic_on_warn rapidio: fix the missed put_device() for rio_mport_add_riodev rapidio: fix error handling path nilfs2: fix some kernel-doc warnings for nilfs2 autofs: harden ioctl table ramfs: fix nommu mmap with gaps in the page cache mm: remove the now-unnecessary mmget_still_valid() hack mm/gup: take mmap_lock in get_dump_page() binfmt_elf, binfmt_elf_fdpic: use a VMA list snapshot coredump: rework elf/elf_fdpic vma_dump_size() into common helper coredump: refactor page range dumping into common helper coredump: let dump_emit() bail out on short writes ...
2020-10-16lib, include/linux: add usercopy failure capabilityAlbert van der Linde1-0/+1
Patch series "add fault injection to user memory access", v3. The goal of this series is to improve testing of fault-tolerance in usages of user memory access functions, by adding support for fault injection. syzkaller/syzbot are using the existing fault injection modes and will use this particular feature also. The first patch adds failure injection capability for usercopy functions. The second changes usercopy functions to use this new failure capability (copy_from_user, ...). The third patch adds get/put/clear_user failures to x86. This patch (of 3): Add a failure injection capability to improve testing of fault-tolerance in usages of user memory access functions. Add CONFIG_FAULT_INJECTION_USERCOPY to enable faults in usercopy functions. The should_fail_usercopy function is to be called by these functions (copy_from_user, get_user, ...) in order to fail or not. Signed-off-by: Albert van der Linde <alinde@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Akinobu Mita <akinobu.mita@gmail.com> Reviewed-by: Alexander Potapenko <glider@google.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Marco Elver <elver@google.com> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20200831171733.955393-1-alinde@google.com Link: http://lkml.kernel.org/r/20200831171733.955393-2-alinde@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-15Merge tag 'net-next-5.10' of ↵Linus Torvalds1-0/+5
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Jakub Kicinski: - Add redirect_neigh() BPF packet redirect helper, allowing to limit stack traversal in common container configs and improving TCP back-pressure. Daniel reports ~10Gbps => ~15Gbps single stream TCP performance gain. - Expand netlink policy support and improve policy export to user space. (Ge)netlink core performs request validation according to declared policies. Expand the expressiveness of those policies (min/max length and bitmasks). Allow dumping policies for particular commands. This is used for feature discovery by user space (instead of kernel version parsing or trial and error). - Support IGMPv3/MLDv2 multicast listener discovery protocols in bridge. - Allow more than 255 IPv4 multicast interfaces. - Add support for Type of Service (ToS) reflection in SYN/SYN-ACK packets of TCPv6. - In Multi-patch TCP (MPTCP) support concurrent transmission of data on multiple subflows in a load balancing scenario. Enhance advertising addresses via the RM_ADDR/ADD_ADDR options. - Support SMC-Dv2 version of SMC, which enables multi-subnet deployments. - Allow more calls to same peer in RxRPC. - Support two new Controller Area Network (CAN) protocols - CAN-FD and ISO 15765-2:2016. - Add xfrm/IPsec compat layer, solving the 32bit user space on 64bit kernel problem. - Add TC actions for implementing MPLS L2 VPNs. - Improve nexthop code - e.g. handle various corner cases when nexthop objects are removed from groups better, skip unnecessary notifications and make it easier to offload nexthops into HW by converting to a blocking notifier. - Support adding and consuming TCP header options by BPF programs, opening the doors for easy experimental and deployment-specific TCP option use. - Reorganize TCP congestion control (CC) initialization to simplify life of TCP CC implemented in BPF. - Add support for shipping BPF programs with the kernel and loading them early on boot via the User Mode Driver mechanism, hence reusing all the user space infra we have. - Support sleepable BPF programs, initially targeting LSM and tracing. - Add bpf_d_path() helper for returning full path for given 'struct path'. - Make bpf_tail_call compatible with bpf-to-bpf calls. - Allow BPF programs to call map_update_elem on sockmaps. - Add BPF Type Format (BTF) support for type and enum discovery, as well as support for using BTF within the kernel itself (current use is for pretty printing structures). - Support listing and getting information about bpf_links via the bpf syscall. - Enhance kernel interfaces around NIC firmware update. Allow specifying overwrite mask to control if settings etc. are reset during update; report expected max time operation may take to users; support firmware activation without machine reboot incl. limits of how much impact reset may have (e.g. dropping link or not). - Extend ethtool configuration interface to report IEEE-standard counters, to limit the need for per-vendor logic in user space. - Adopt or extend devlink use for debug, monitoring, fw update in many drivers (dsa loop, ice, ionic, sja1105, qed, mlxsw, mv88e6xxx, dpaa2-eth). - In mlxsw expose critical and emergency SFP module temperature alarms. Refactor port buffer handling to make the defaults more suitable and support setting these values explicitly via the DCBNL interface. - Add XDP support for Intel's igb driver. - Support offloading TC flower classification and filtering rules to mscc_ocelot switches. - Add PTP support for Marvell Octeontx2 and PP2.2 hardware, as well as fixed interval period pulse generator and one-step timestamping in dpaa-eth. - Add support for various auth offloads in WiFi APs, e.g. SAE (WPA3) offload. - Add Lynx PHY/PCS MDIO module, and convert various drivers which have this HW to use it. Convert mvpp2 to split PCS. - Support Marvell Prestera 98DX3255 24-port switch ASICs, as well as 7-port Mediatek MT7531 IP. - Add initial support for QCA6390 and IPQ6018 in ath11k WiFi driver, and wcn3680 support in wcn36xx. - Improve performance for packets which don't require much offloads on recent Mellanox NICs by 20% by making multiple packets share a descriptor entry. - Move chelsio inline crypto drivers (for TLS and IPsec) from the crypto subtree to drivers/net. Move MDIO drivers out of the phy directory. - Clean up a lot of W=1 warnings, reportedly the actively developed subsections of networking drivers should now build W=1 warning free. - Make sure drivers don't use in_interrupt() to dynamically adapt their code. Convert tasklets to use new tasklet_setup API (sadly this conversion is not yet complete). * tag 'net-next-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2583 commits) Revert "bpfilter: Fix build error with CONFIG_BPFILTER_UMH" net, sockmap: Don't call bpf_prog_put() on NULL pointer bpf, selftest: Fix flaky tcp_hdr_options test when adding addr to lo bpf, sockmap: Add locking annotations to iterator netfilter: nftables: allow re-computing sctp CRC-32C in 'payload' statements net: fix pos incrementment in ipv6_route_seq_next net/smc: fix invalid return code in smcd_new_buf_create() net/smc: fix valid DMBE buffer sizes net/smc: fix use-after-free of delayed events bpfilter: Fix build error with CONFIG_BPFILTER_UMH cxgb4/ch_ipsec: Replace the module name to ch_ipsec from chcr net: sched: Fix suspicious RCU usage while accessing tcf_tunnel_info bpf: Fix register equivalence tracking. rxrpc: Fix loss of final ack on shutdown rxrpc: Fix bundle counting for exclusive connections netfilter: restore NF_INET_NUMHOOKS ibmveth: Identify ingress large send packets. ibmveth: Switch order of ibmveth_helper calls. cxgb4: handle 4-tuple PEDIT to NAT mode translation selftests: Add VRF route leaking tests ...
2020-10-15Merge tag 'dma-mapping-5.10' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds1-1/+12
Pull dma-mapping updates from Christoph Hellwig: - rework the non-coherent DMA allocator - move private definitions out of <linux/dma-mapping.h> - lower CMA_ALIGNMENT (Paul Cercueil) - remove the omap1 dma address translation in favor of the common code - make dma-direct aware of multiple dma offset ranges (Jim Quinlan) - support per-node DMA CMA areas (Barry Song) - increase the default seg boundary limit (Nicolin Chen) - misc fixes (Robin Murphy, Thomas Tai, Xu Wang) - various cleanups * tag 'dma-mapping-5.10' of git://git.infradead.org/users/hch/dma-mapping: (63 commits) ARM/ixp4xx: add a missing include of dma-map-ops.h dma-direct: simplify the DMA_ATTR_NO_KERNEL_MAPPING handling dma-direct: factor out a dma_direct_alloc_from_pool helper dma-direct check for highmem pages in dma_direct_alloc_pages dma-mapping: merge <linux/dma-noncoherent.h> into <linux/dma-map-ops.h> dma-mapping: move large parts of <linux/dma-direct.h> to kernel/dma dma-mapping: move dma-debug.h to kernel/dma/ dma-mapping: remove <asm/dma-contiguous.h> dma-mapping: merge <linux/dma-contiguous.h> into <linux/dma-map-ops.h> dma-contiguous: remove dma_contiguous_set_default dma-contiguous: remove dev_set_cma_area dma-contiguous: remove dma_declare_contiguous dma-mapping: split <linux/dma-mapping.h> cma: decrease CMA_ALIGNMENT lower limit to 2 firewire-ohci: use dma_alloc_pages dma-iommu: implement ->alloc_noncoherent dma-mapping: add new {alloc,free}_noncoherent dma_map_ops methods dma-mapping: add a new dma_alloc_pages API dma-mapping: remove dma_cache_sync 53c700: convert to dma_alloc_noncoherent ...
2020-10-12Merge tag 'docs-5.10' of git://git.lwn.net/linuxLinus Torvalds1-15/+23
Pull documentation updates from Jonathan Corbet: "As hoped, things calmed down for docs this cycle; fewer changes and almost no conflicts at all. This includes: - A reworked and expanded user-mode Linux document - Some simplifications and improvements for submitting-patches.rst - An emergency fix for (some) problems with Sphinx 3.x - Some welcome automarkup improvements to automatically generate cross-references to struct definitions and other documents - The usual collection of translation updates, typo fixes, etc" * tag 'docs-5.10' of git://git.lwn.net/linux: (81 commits) gpiolib: Update indentation in driver.rst for code excerpts Documentation/admin-guide: tainted-kernels: Fix typo occured Documentation: better locations for sysfs-pci, sysfs-tagging docs: programming-languages: refresh blurb on clang support Documentation: kvm: fix a typo Documentation: Chinese translation of Documentation/arm64/amu.rst doc: zh_CN: index files in arm64 subdirectory mailmap: add entry for <mstarovoitov@marvell.com> doc: seq_file: clarify role of *pos in ->next() docs: trace: ring-buffer-design.rst: use the new SPDX tag Documentation: kernel-parameters: clarify "module." parameters Fix references to nommu-mmap.rst docs: rewrite admin-guide/sysctl/abi.rst docs: fb: Remove vesafb scrollback boot option docs: fb: Remove sstfb scrollback boot option docs: fb: Remove matroxfb scrollback boot option docs: fb: Remove framebuffer scrollback boot option docs: replace the old User Mode Linux HowTo with a new one Documentation/admin-guide: blockdev/ramdisk: remove use of "rdev" Documentation/admin-guide: README & svga: remove use of "rdev" ...
2020-10-09Merge branch 'for-mingo' of ↵Ingo Molnar1-18/+135
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu Pull v5.10 RCU changes from Paul E. McKenney: - Debugging for smp_call_function(). - Strict grace periods for KASAN. The point of this series is to find RCU-usage bugs, so the corresponding new RCU_STRICT_GRACE_PERIOD Kconfig option depends on both DEBUG_KERNEL and RCU_EXPERT, and is further disabled by dfefault. Finally, the help text includes a goodly list of scary caveats. - New smp_call_function() torture test. - Torture-test updates. - Documentation updates. - Miscellaneous fixes. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-10-06dma-mapping: merge <linux/dma-contiguous.h> into <linux/dma-map-ops.h>Christoph Hellwig1-1/+1
Merge dma-contiguous.h into dma-map-ops.h, after removing the comment describing the contiguous allocator into kernel/dma/contigous.c. Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-09-24Documentation: kernel-parameters: clarify "module." parametersRandy Dunlap1-2/+2
The command-line parameters "dyndbg" and "async_probe" are not parameters for kernel/module.c but instead they are for the module that is being loaded. Try to make that distinction in the help text. OTOH, "module.sig_enforce" is handled as a parameter of kernel/module.c so "module." is correct for it. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jessica Yu <jeyu@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Link: https://lore.kernel.org/r/67d40b6d-c073-a3bf-cbb6-6cad941cceeb@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-24Documentation/admin-guide: blockdev/ramdisk: remove use of "rdev"Randy Dunlap1-5/+4
Remove use of "rdev" from blockdev/ramdisk.rst and update admin-guide/kernel-parameters.txt. "rdev" is considered antiquated, ancient, archaic, obsolete, deprecated {choose any or all}. "rdev" was removed from util-linux in 2010: https://git.kernel.org/pub/scm/utils/util-linux/util-linux.git/commit/?id=a3e40c14651fccf18e7954f081e601389baefe3f Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Karel Zak <kzak@redhat.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: linux-block@vger.kernel.org Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Martin Mares <mj@ucw.cz> Cc: linux-video@atrey.karlin.mff.cuni.cz Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Link: https://lore.kernel.org/r/20200918015640.8439-3-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-24Documentation/admin-guide: kernel-parameters: capitalize KorinaRandy Dunlap1-1/+1
Fix typo, capitalize Korina proper noun. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Link: https://lore.kernel.org/r/20200918054722.28713-1-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-24Documentation: admin-guide: kernel-parameters: reformat "lapic=" boot optionRandy Dunlap1-1/+2
Reformat "lapic=" to try to make it more understandable and similar to the style that is mostly used in this file. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Link: https://lore.kernel.org/r/20200918054739.2523-1-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-24Documentation/admin-guide: kernel-parameters: fix "io7" parameter descriptionRandy Dunlap1-1/+1
Fix punctuation and capitalization for the "io7" boot parameter. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Link: https://lore.kernel.org/r/20200918054751.6538-1-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-24Documentation/admin-guide: kernel-parameters: fix "disable_ddw" wordingRandy Dunlap1-1/+1
Drop and extraneous word (if) in a sentence. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Link: https://lore.kernel.org/r/20200918054803.6588-1-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-24Documentation: Remove CMA's dependency on architectureTian Tao1-1/+1
CMA only depends on MMU. It doesn't depend on arch too much. such as ARM, ARM64, X86, MIPS etc. so We remove the dependency of cma about the architecture in kernel-parameters.txt. Signed-off-by: Tian Tao <tiantao6@hisilicon.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Link: https://lore.kernel.org/r/1600412758-60545-1-git-send-email-tiantao6@hisilicon.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-24Documentation: kernel-parameters: fix formatting of MIPS "machtype"Randy Dunlap1-2/+2
For the "machtype" boot parameter, fix word spacing, line wrap, and plural of "laptops". Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Jiaxun Yang <jiaxun.yang@flygoat.com> Link: https://lore.kernel.org/r/c9059e35-188d-a749-1907-767b53479328@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-24Doc: admin-guide: Add entry for kvm_cma_resv_ratio kernel paramSatheesh Rajendran1-0/+8
Add document entry for kvm_cma_resv_ratio kernel param which is used to alter the KVM contiguous memory allocation percentage for hash pagetable allocation used by hash mode PowerPC KVM guests. Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com> Link: https://lore.kernel.org/r/20200921090220.14981-1-sathnaga@linux.vnet.ibm.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-16Documentation: arm64 also supports disable hugeiomapTian Tao1-1/+1
arm64 also supports disable hugeiomap,updated documentation. Signed-off-by: Tian Tao <tiantao6@hisilicon.com> Link: https://lore.kernel.org/r/1599740386-47210-1-git-send-email-tiantao6@hisilicon.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-10x86/fpu: Allow multiple bits in clearcpuid= parameterArvind Sankar1-1/+1
Commit 0c2a3913d6f5 ("x86/fpu: Parse clearcpuid= as early XSAVE argument") changed clearcpuid parsing from __setup() to cmdline_find_option(). While the __setup() function would have been called for each clearcpuid= parameter on the command line, cmdline_find_option() will only return the last one, so the change effectively made it impossible to disable more than one bit. Allow a comma-separated list of bit numbers as the argument for clearcpuid to allow multiple bits to be disabled again. Log the bits being disabled for informational purposes. Also fix the check on the return value of cmdline_find_option(). It returns -1 when the option is not found, so testing as a boolean is incorrect. Fixes: 0c2a3913d6f5 ("x86/fpu: Parse clearcpuid= as early XSAVE argument") Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20200907213919.2423441-1-nivedita@alum.mit.edu
2020-09-04Merge branch 'csd.2020.09.04a' into HEADPaul E. McKenney1-0/+4
csd.2020.09.04a: CPU smp_call_function() torture tests.
2020-09-03Merge branch 'strictgp.2020.08.24a' into HEADPaul E. McKenney1-0/+9
strictgp.2020.08.24a: Strict grace periods for KASAN testing.
2020-09-03Merge branch 'scftorture.2020.08.24a' into HEADPaul E. McKenney1-18/+110
scftorture.2020.08.24a: Torture tests for smp_call_function() and friends.
2020-09-01dma-contiguous: provide the ability to reserve per-numa CMABarry Song1-0/+11
Right now, drivers like ARM SMMU are using dma_alloc_coherent() to get coherent DMA buffers to save their command queues and page tables. As there is only one default CMA in the whole system, SMMUs on nodes other than node0 will get remote memory. This leads to significant latency. This patch provides per-numa CMA so that drivers like SMMU can get local memory. Tests show localizing CMA can decrease dma_unmap latency much. For instance, before this patch, SMMU on node2 has to wait for more than 560ns for the completion of CMD_SYNC in an empty command queue; with this patch, it needs 240ns only. A positive side effect of this patch would be improving performance even further for those users who are worried about performance more than DMA security and use iommu.passthrough=1 to skip IOMMU. With local CMA, all drivers can get local coherent DMA buffers. Also, this patch changes the default CONFIG_CMA_AREAS to 19 in NUMA. As 1+CONFIG_CMA_AREAS should be quite enough for most servers on the market even they enable both hugetlb_cma and pernuma_cma. 2 numa nodes: 2(hugetlb) + 2(pernuma) + 1(default global cma) = 5 4 numa nodes: 4(hugetlb) + 4(pernuma) + 1(default global cma) = 9 8 numa nodes: 8(hugetlb) + 8(pernuma) + 1(default global cma) = 17 Signed-off-by: Barry Song <song.bao.hua@hisilicon.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-08-28net: add option to not create fall-back tunnels in root-ns as wellMahesh Bandewar1-0/+5
The sysctl that was added earlier by commit 79134e6ce2c ("net: do not create fallback tunnels for non-default namespaces") to create fall-back only in root-ns. This patch enhances that behavior to provide option not to create fallback tunnels in root-ns as well. Since modules that create fallback tunnels could be built-in and setting the sysctl value after booting is pointless, so added a kernel cmdline options to change this default. The default setting is preseved for backward compatibility. The kernel command line option of fb_tunnels=initns will set the sysctl value to 1 and will create fallback tunnels only in initns while kernel cmdline fb_tunnels=none will set the sysctl value to 2 and fallback tunnels are skipped in every netns. Signed-off-by: Mahesh Bandewar <maheshb@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Maciej Zenczykowski <maze@google.com> Cc: Jian Yang <jianyang@google.com> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-24rcutorture: Allow pointer leaks to test diagnostic codePaul E. McKenney1-0/+12
This commit adds an rcutorture.leakpointer module parameter that intentionally leaks an RCU-protected pointer out of the RCU read-side critical section and checks to see if the corresponding grace period has elapsed, emitting a WARN_ON_ONCE() if so. This module parameter can be used to test facilities like CONFIG_RCU_STRICT_GRACE_PERIOD that end grace periods quickly. While in the area, also document rcutorture.irqreader, which was previously left out. Reported-by Jann Horn <jannh@google.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-08-24rcu: Provide optional RCU-reader exit delay for strict GPsPaul E. McKenney1-0/+9
The goal of this series is to increase the probability of tools like KASAN detecting that an RCU-protected pointer was used outside of its RCU read-side critical section. Thus far, the approach has been to make grace periods and callback processing happen faster. Another approach is to delay the pointer leaker. This commit therefore allows a delay to be applied to exit from RCU read-side critical sections. This slowdown is specified by a new rcutree.rcu_unlock_delay kernel boot parameter that specifies this delay in microseconds, defaulting to zero. Reported-by Jann Horn <jannh@google.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-08-24rcuperf: Change rcuperf to rcuscalePaul E. McKenney1-18/+18
This commit further avoids conflation of rcuperf with the kernel's perf feature by renaming kernel/rcu/rcuperf.c to kernel/rcu/rcuscale.c, and also by similarly renaming the functions and variables inside this file. This has the side effect of changing the names of the kernel boot parameters, so kernel-parameters.txt and ver_functions.sh are also updated. The rcutorture --torture type was also updated from rcuperf to rcuscale. [ paulmck: Fix bugs located by Stephen Rothwell. ] Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-08-24scftorture: Add smp_call_function() torture testPaul E. McKenney1-0/+92
This commit adds an smp_call_function() torture test that repeatedly invokes this function and complains if things go badly awry. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-08-24lib: Add backtrace_idle parameter to force backtrace of idle CPUsPaul E. McKenney1-0/+4
Currently, the nmi_cpu_backtrace() declines to produce backtraces for idle CPUs. This is a good choice in the common case in which problems are caused only by non-idle CPUs. However, there are occasionally situations in which idle CPUs are helping to cause problems. This commit therefore adds an nmi_backtrace.backtrace_idle kernel boot parameter that causes nmi_cpu_backtrace() to dump stacks even of idle CPUs. Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: <linux-doc@vger.kernel.org>