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2017-06-08rcuperf: Add writer_holdoff boot parameterPaul E. McKenney1-3/+8
This commit adds a writer_holdoff boot parameter to rcuperf, which is intended to be used to test Tree SRCU's auto-expediting. This boot parameter is in microseconds, and defaults to zero (that is, disabled). Set it to a bit larger than srcutree.exp_holdoff, keeping the nanosecond/microsecond conversion, to force Tree SRCU to auto-expedite more aggressively. This commit also adds documentation for this parameter, and fixes some alphabetization while in the neighborhood. Signed-off-by: Paul E. McKenney <[email protected]>
2017-06-08rcuperf: Add ability to performance-test call_rcu() and friendsPaul E. McKenney1-0/+11
This commit upgrades rcuperf so that it can do performance testing on asynchronous grace-period primitives such as call_srcu(). There is a new rcuperf.gp_async module parameter that specifies this new behavior, with the pre-existing rcuperf.gp_exp testing expedited grace periods such as synchronize_rcu_expedited, and with the default being to test synchronous non-expedited grace periods such as synchronize_rcu(). There is also a new rcuperf.gp_async_max module parameter that specifies the maximum number of outstanding callbacks per writer kthread, defaulting to 1,000. When this limit is exceeded, the writer thread invokes the appropriate flavor of rcu_barrier() to wait for callbacks to drain. Signed-off-by: Paul E. McKenney <[email protected]> [ paulmck: Removed the redundant initialization noted by Arnd Bergmann. ]
2017-06-01powerpc/64s: Add dt_cpu_ftrs boot time setup optionNicholas Piggin1-0/+9
Provide a dt_cpu_ftrs= cmdline option to disable the dt_cpu_ftrs CPU feature discovery, and fall back to the "cputable" based version. Also allow control of advertising unknown features to userspace and with this parameter, and remove the clunky CONFIG option. Signed-off-by: Nicholas Piggin <[email protected]> [mpe: Add explicit early check of bootargs in dt_cpu_ftrs_init()] Signed-off-by: Michael Ellerman <[email protected]>
2017-05-24Documentation/kernel-parameters.txt: Update 'memmap=' boot option descriptionBaoquan He1-0/+9
In commit: 9710f581bb4c ("x86, mm: Let "memmap=" take more entries one time") ... 'memmap=' was changed to adopt multiple, comma delimited values in a single entry, so update the related description. In the special case of only specifying size value without an offset, like memmap=nn[KMG], memmap behaves similarly to mem=nn[KMG], so update it too here. Furthermore, for memmap=nn[KMG]$ss[KMG], an escape character needs be added before '$' for some bootloaders. E.g in grub2, if we specify memmap=100M$5G as suggested by the documentation, "memmap=100MG" gets passed to the kernel. Clarify all this. Signed-off-by: Baoquan He <[email protected]> Acked-by: Kees Cook <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] [ Various spelling fixes. ] Signed-off-by: Ingo Molnar <[email protected]>
2017-05-18Merge remote-tracking branch 'mauro-exp/docbook3' into death-to-docbookJonathan Corbet1-6/+0
Mauro says: This patch series convert the remaining DocBooks to ReST. The first version was originally send as 3 patch series: [PATCH 00/36] Convert DocBook documents to ReST [PATCH 0/5] Convert more books to ReST [PATCH 00/13] Get rid of DocBook The lsm book was added as if it were a text file under Documentation. The plan is to merge it with another file under Documentation/security, after both this series and a security Documentation patch series gets merged. It also adjusts some Sphinx-pedantic errors/warnings on some kernel-doc markups. I also added some patches here to add PDF output for all existing ReST books.
2017-05-18doc: ReSTify Smack.txtKees Cook2-0/+858
Adjusts for ReST markup and moves under LSM admin guide. Acked-by: Casey Schaufler <[email protected]> Signed-off-by: Kees Cook <[email protected]> Signed-off-by: Jonathan Corbet <[email protected]>
2017-05-18doc: ReSTify LoadPin.txtKees Cook2-0/+22
Adjusts for ReST markup and moves under LSM admin guide. Signed-off-by: Kees Cook <[email protected]> Signed-off-by: Jonathan Corbet <[email protected]>
2017-05-18doc: ReSTify Yama.txtKees Cook2-0/+75
Adjusts for ReST markup and moves under LSM admin guide. Signed-off-by: Kees Cook <[email protected]> Signed-off-by: Jonathan Corbet <[email protected]>
2017-05-18doc: ReSTify tomoyo.txtKees Cook2-0/+66
Adjusts for ReST markup and moves under LSM admin guide. Cc: Tetsuo Handa <[email protected]> Signed-off-by: Kees Cook <[email protected]> Signed-off-by: Jonathan Corbet <[email protected]>
2017-05-18doc: ReSTify apparmor.txtKees Cook2-0/+52
Adjusts for ReST markup and moves under LSM admin guide. Acked-by: John Johansen <[email protected]> Signed-off-by: Kees Cook <[email protected]> Signed-off-by: Jonathan Corbet <[email protected]>
2017-05-18doc: ReSTify SELinux.txtKees Cook2-0/+38
Adjusts for ReST markup and moves under LSM admin guide. Cc: Paul Moore <[email protected]> Signed-off-by: Kees Cook <[email protected]> Signed-off-by: Jonathan Corbet <[email protected]>
2017-05-18doc: ReSTify and split LSM.txtKees Cook2-0/+32
The existing LSM.txt file covered both usage and development, so split this into two files, one under admin-guide and one under kernel development. Cc: James Morris <[email protected]> Signed-off-by: Kees Cook <[email protected]> Signed-off-by: Jonathan Corbet <[email protected]>
2017-05-18vhost/vsock: use static minor numberStefan Hajnoczi1-1/+3
Vhost-vsock is a software device so there is no probe call that causes the driver to register its misc char device node. This creates a chicken and egg problem: userspace applications must open /dev/vhost-vsock to use the driver but the file doesn't exist until the kernel module has been loaded. Use the devname modalias mechanism so that /dev/vhost-vsock is created at boot. The vhost_vsock kernel module is automatically loaded when the first application opens /dev/host-vsock. Note that the "reserved for local use" range in Documentation/admin-guide/devices.txt is incorrect. The userio driver already occupies part of that range. I've updated the documentation accordingly. Cc: [email protected] Signed-off-by: Stefan Hajnoczi <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
2017-05-16docs: update old references for DocBook from the documentationMauro Carvalho Chehab1-6/+0
DocBook is mentioned several times at the documentation. Update the obsolete references from it at the DocBook. Acked-by: SeongJae Park <[email protected]> Signed-off-by: Mauro Carvalho Chehab <[email protected]>
2017-05-14cpufreq: intel_pstate: Document the current behavior and user interfaceRafael J. Wysocki3-9/+766
Add a document describing the current behavior and user space interface of the intel_pstate driver in the RST format and drop the existing outdated intel_pstate.txt document. Also update admin-guide/pm/cpufreq.rst with proper RST references to the new intel_pstate.rst document. Signed-off-by: Rafael J. Wysocki <[email protected]>
2017-05-11Merge tag 'docs-4.12-2' of git://git.lwn.net/linuxLinus Torvalds2-2/+2
Pull more documentation updates from Jonathan Corbet: "Connect the newly RST-formatted documentation to the rest; this had to wait until the input pull was done. There's also a few small fixes that wandered in" * tag 'docs-4.12-2' of git://git.lwn.net/linux: doc: replace FTP URL to kernel.org with HTTPS one docs: update references to the device io book Documentation: earlycon: fix Marvell Armada 3700 UART name docs-rst: add input docs at main index and use kernel-figure
2017-05-11doc: replace FTP URL to kernel.org with HTTPS oneMichael Heimpold1-1/+1
FTP services were shutdown some weeks ago, so the FTP URL does not work anymore. Fix this by replacing it with corresponding HTTPS URL. Signed-off-by: Michael Heimpold <[email protected]> Signed-off-by: Jonathan Corbet <[email protected]>
2017-05-10Merge tag 'nfs-for-4.12-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds1-6/+0
Pull NFS client updates from Trond Myklebust: "Highlights include: Stable bugfixes: - Fix use after free in write error path - Use GFP_NOIO for two allocations in writeback - Fix a hang in OPEN related to server reboot - Check the result of nfs4_pnfs_ds_connect - Fix an rcu lock leak Features: - Removal of the unmaintained and unused OSD pNFS layout - Cleanup and removal of lots of unnecessary dprintk()s - Cleanup and removal of some memory failure paths now that GFP_NOFS is guaranteed to never fail. - Remove the v3-only data server limitation on pNFS/flexfiles Bugfixes: - RPC/RDMA connection handling bugfixes - Copy offload: fixes to ensure the copied data is COMMITed to disk. - Readdir: switch back to using the ->iterate VFS interface - File locking fixes from Ben Coddington - Various use-after-free and deadlock issues in pNFS - Write path bugfixes" * tag 'nfs-for-4.12-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (89 commits) pNFS/flexfiles: Always attempt to call layoutstats when flexfiles is enabled NFSv4.1: Work around a Linux server bug... NFS append COMMIT after synchronous COPY NFSv4: Fix exclusive create attributes encoding NFSv4: Fix an rcu lock leak nfs: use kmap/kunmap directly NFS: always treat the invocation of nfs_getattr as cache hit when noac is on Fix nfs_client refcounting if kmalloc fails in nfs4_proc_exchange_id and nfs4_proc_async_renew NFSv4.1: RECLAIM_COMPLETE must handle NFS4ERR_CONN_NOT_BOUND_TO_SESSION pNFS: Fix NULL dereference in pnfs_generic_alloc_ds_commits pNFS: Fix a typo in pnfs_generic_alloc_ds_commits pNFS: Fix a deadlock when coalescing writes and returning the layout pNFS: Don't clear the layout return info if there are segments to return pNFS: Ensure we commit the layout if it has been invalidated pNFS: Don't send COMMITs to the DSes if the server invalidated our layout pNFS/flexfiles: Fix up the ff_layout_write_pagelist failure path pNFS: Ensure we check layout validity before marking it for return NFS4.1 handle interrupted slot reuse from ERR_DELAY NFSv4: check return value of xdr_inline_decode nfs/filelayout: fix NULL pointer dereference in fl_pnfs_update_layout() ...
2017-05-10Merge branch 'core-rcu-for-linus' of ↵Linus Torvalds1-0/+8
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU updates from Ingo Molnar: "The main changes are: - Debloat RCU headers - Parallelize SRCU callback handling (plus overlapping patches) - Improve the performance of Tree SRCU on a CPU-hotplug stress test - Documentation updates - Miscellaneous fixes" * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (74 commits) rcu: Open-code the rcu_cblist_n_lazy_cbs() function rcu: Open-code the rcu_cblist_n_cbs() function rcu: Open-code the rcu_cblist_empty() function rcu: Separately compile large rcu_segcblist functions srcu: Debloat the <linux/rcu_segcblist.h> header srcu: Adjust default auto-expediting holdoff srcu: Specify auto-expedite holdoff time srcu: Expedite first synchronize_srcu() when idle srcu: Expedited grace periods with reduced memory contention srcu: Make rcutorture writer stalls print SRCU GP state srcu: Exact tracking of srcu_data structures containing callbacks srcu: Make SRCU be built by default srcu: Fix Kconfig botch when SRCU not selected rcu: Make non-preemptive schedule be Tasks RCU quiescent state srcu: Expedite srcu_schedule_cbs_snp() callback invocation srcu: Parallelize callback handling kvm: Move srcu_struct fields to end of struct kvm rcu: Fix typo in PER_RCU_NODE_PERIOD header comment rcu: Use true/false in assignment to bool rcu: Use bool value directly ...
2017-05-09Merge tag 'iommu-updates-v4.12' of ↵Linus Torvalds1-0/+15
git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu Pull IOMMU updates from Joerg Roedel: - code optimizations for the Intel VT-d driver - ability to switch off a previously enabled Intel IOMMU - support for 'struct iommu_device' for OMAP, Rockchip and Mediatek IOMMUs - header optimizations for IOMMU core code headers and a few fixes that became necessary in other parts of the kernel because of that - ACPI/IORT updates and fixes - Exynos IOMMU optimizations - updates for the IOMMU dma-api code to bring it closer to use per-cpu iova caches - new command-line option to set default domain type allocated by the iommu core code - another command line option to allow the Intel IOMMU switched off in a tboot environment - ARM/SMMU: TLB sync optimisations for SMMUv2, Support for using an IDENTITY domain in conjunction with DMA ops, Support for SMR masking, Support for 16-bit ASIDs (was previously broken) - various other small fixes and improvements * tag 'iommu-updates-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (63 commits) soc/qbman: Move dma-mapping.h include to qman_priv.h soc/qbman: Fix implicit header dependency now causing build fails iommu: Remove trace-events include from iommu.h iommu: Remove pci.h include from trace/events/iommu.h arm: dma-mapping: Don't override dma_ops in arch_setup_dma_ops() ACPI/IORT: Fix CONFIG_IOMMU_API dependency iommu/vt-d: Don't print the failure message when booting non-kdump kernel iommu: Move report_iommu_fault() to iommu.c iommu: Include device.h in iommu.h x86, iommu/vt-d: Add an option to disable Intel IOMMU force on iommu/arm-smmu: Return IOVA in iova_to_phys when SMMU is bypassed iommu/arm-smmu: Correct sid to mask iommu/amd: Fix incorrect error handling in amd_iommu_bind_pasid() iommu: Make iommu_bus_notifier return NOTIFY_DONE rather than error code omap3isp: Remove iommu_group related code iommu/omap: Add iommu-group support iommu/omap: Make use of 'struct iommu_device' iommu/omap: Store iommu_dev pointer in arch_data iommu/omap: Move data structures to omap-iommu.h iommu/omap: Drop legacy-style device support ...
2017-05-09Documentation: earlycon: fix Marvell Armada 3700 UART nameAndre Przywara1-1/+1
The Marvell Armada 3700 UART uses "ar3700_uart" for its earlycon name. Adjust documentation to match the code. Signed-off-by: Andre Przywara <[email protected]> Signed-off-by: Jonathan Corbet <[email protected]>
2017-05-04Merge branches 'arm/exynos', 'arm/omap', 'arm/rockchip', 'arm/mediatek', ↵Joerg Roedel1-0/+21
'arm/smmu', 'arm/core', 'x86/vt-d', 'x86/amd' and 'core' into next
2017-05-03Merge branch 'for-linus' of ↵Linus Torvalds1-3/+29
git://git.kernel.org/pub/scm/linux/kernel/git/shli/md Pull MD updates from Shaohua Li: - Add Partial Parity Log (ppl) feature found in Intel IMSM raid array by Artur Paszkiewicz. This feature is another way to close RAID5 writehole. The Linux implementation is also available for normal RAID5 array if specific superblock bit is set. - A number of md-cluser fixes and enabling md-cluster array resize from Guoqing Jiang - A bunch of patches from Ming Lei and Neil Brown to rewrite MD bio handling related code. Now MD doesn't directly access bio bvec, bi_phys_segments and uses modern bio API for bio split. - Improve RAID5 IO pattern to improve performance for hard disk based RAID5/6 from me. - Several patches from Song Liu to speed up raid5-cache recovery and allow raid5 cache feature disabling in runtime. - Fix a performance regression in raid1 resync from Xiao Ni. - Other cleanup and fixes from various people. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md: (84 commits) md/raid10: skip spare disk as 'first' disk md/raid1: Use a new variable to count flighting sync requests md: clear WantReplacement once disk is removed md/raid1/10: remove unused queue md: handle read-only member devices better. md/raid10: wait up frozen array in handle_write_completed uapi: fix linux/raid/md_p.h userspace compilation error md-cluster: Fix a memleak in an error handling path md: support disabling of create-on-open semantics. md: allow creation of mdNNN arrays via md_mod/parameters/new_array raid5-ppl: use a single mempool for ppl_io_unit and header_page md/raid0: fix up bio splitting. md/linear: improve bio splitting. md/raid5: make chunk_aligned_read() split bios more cleanly. md/raid10: simplify handle_read_error() md/raid10: simplify the splitting of requests. md/raid1: factor out flush_bio_list() md/raid1: simplify handle_read_error(). Revert "block: introduce bio_copy_data_partial" md/raid1: simplify alloc_behind_master_bio() ...
2017-05-02Merge branch 'for-linus' of ↵Linus Torvalds1-0/+3
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid Pull HID subsystem updates from Jiri Kosina: - The need for HID_QUIRK_NO_INIT_REPORTS per-device quirk has been growing dramatically during past years, so the time has come to switch over the default, and perform the pro-active reading only in cases where it's really needed (multitouch, wacom). The only place where this behavior is (in some form) preserved is hiddev so that we don't introduce userspace-visible change of behavior. From Benjamin Tissoires - HID++ support for power_supply / baterry reporting. From Benjamin Tissoires and Bastien Nocera - Vast improvements / rework of DS3 and DS4 in Sony driver. From Roderick Colenbrander - Improvment (in terms of getting closer to the Microsoft's interpretation of slightly ambiguous specification) of logical range interpretation in case null-state is set in the rdesc. From Valtteri Heikkilä and Tomasz Kramkowski - A lot of newly supported device IDs and small assorted fixes * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid: (71 commits) HID: usbhid: Add HID_QUIRK_NOGET for Aten CS-1758 KVM switch HID: asus: support backlight on USB keyboards HID: wacom: Move wacom_remote_irq and wacom_remote_status_irq HID: wacom: generic: sync pad events only for actual packets HID: sony: remove redundant check for -ve err HID: sony: Make sure to unregister sensors on failure HID: sony: Make DS4 bt poll interval adjustable HID: sony: Set proper bit flags on DS4 output report HID: sony: DS4 use brighter LED colors HID: sony: Improve navigation controller axis/button mapping HID: sony: Use DS3 MAC address as unique identifier on USB HID: logitech-hidpp: add a sysfs file to tell we support power_supply HID: logitech-hidpp: enable HID++ 1.0 battery reporting HID: logitech-hidpp: add support for battery status for the K750 HID: logitech-hidpp: battery: provide CAPACITY_LEVEL HID: logitech-hidpp: rename battery level into capacity HID: logitech-hidpp: battery: provide ONLINE property HID: logitech-hidpp: notify battery on connect HID: logitech-hidpp: return an error if the queried feature is not present HID: logitech-hidpp: create the battery for all types of HID++ devices ...
2017-05-02Merge tag 'docs-4.12' of git://git.lwn.net/linuxLinus Torvalds7-13/+761
Pull documentation update from Jonathan Corbet: "A reasonably busy cycle for documentation this time around. There is a new guide for user-space API documents, rather sparsely populated at the moment, but it's a start. Markus improved the infrastructure for converting diagrams. Mauro has converted much of the USB documentation over to RST. Plus the usual set of fixes, improvements, and tweaks. There's a bit more than the usual amount of reaching out of Documentation/ to fix comments elsewhere in the tree; I have acks for those where I could get them" * tag 'docs-4.12' of git://git.lwn.net/linux: (74 commits) docs: Fix a couple typos docs: Fix a spelling error in vfio-mediated-device.txt docs: Fix a spelling error in ioctl-number.txt MAINTAINERS: update file entry for HSI subsystem Documentation: allow installing man pages to a user defined directory Doc/PM: Sync with intel_powerclamp code behavior zr364xx.rst: usb/devices is now at /sys/kernel/debug/ usb.rst: move documentation from proc_usb_info.txt to USB ReST book convert philips.txt to ReST and add to media docs docs-rst: usb: update old usbfs-related documentation arm: Documentation: update a path name docs: process/4.Coding.rst: Fix a couple of document refs docs-rst: fix usb cross-references usb: gadget.h: be consistent at kernel doc macros usb: composite.h: fix two warnings when building docs usb: get rid of some ReST doc build errors usb.rst: get rid of some Sphinx errors usb/URB.txt: convert to ReST and update it usb/persist.txt: convert to ReST and add to driver-api book usb/hotplug.txt: convert to ReST and add to driver-api book ...
2017-05-02Merge branch 'for-4.12/asus' into for-linusJiri Kosina5-6/+41
2017-05-01Merge branch 'x86-debug-for-linus' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 debug updates from Ingo Molnar: "The biggest update is the addition of USB3 debug port based early-console. Greg was fine with the USB changes and with the routing of these patches: https://www.spinics.net/lists/linux-usb/msg155093.html" * 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: usb/doc: Add document for USB3 debug port usage usb/serial: Add DBC debug device support to usb_debug x86/earlyprintk: Add support for earlyprintk via USB3 debug port usb/early: Add driver for xhci debug capability x86/timers: Add simple udelay calibration
2017-05-01Merge branch 'ras-core-for-linus' of ↵Linus Torvalds1-0/+6
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RAS updates from Ingo Molnar: "The main changes in this cycle were: - add the 'Corrected Errors Collector' kernel feature which collect and monitor correctable errors statistics and will preemptively (soft-)offline physical pages that have a suspiciously high error count. - handle MCE errors during kexec() more gracefully - factor out and deprecate the /dev/mcelog driver - ... plus misc fixes and cleanpus" * 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mce: Check MCi_STATUS[MISCV] for usable addr on Intel only ACPI/APEI: Use setup_deferrable_timer() x86/mce: Update notifier priority check x86/mce: Enable PPIN for Knights Landing/Mill x86/mce: Do not register notifiers with invalid prio x86/mce: Factor out and deprecate the /dev/mcelog driver RAS: Add a Corrected Errors Collector x86/mce: Rename mce_log to mce_log_buffer x86/mce: Rename mce_log()'s argument x86/mce: Init some CPU features early x86/mce: Handle broadcasted MCE gracefully with kexec
2017-05-01Merge branch 'md-next' into md-linusShaohua Li1-3/+29
2017-05-01docs: remove all references to AVR32 architectureHans-Christian Noren Egtvedt3-4/+2
The AVR32 architecture support has been removed from the Linux kernel, hence remove all references to it from Documentation. Signed-off-by: Hans-Christian Noren Egtvedt <[email protected]> Signed-off-by: Håvard Skinnemoen <[email protected]> Signed-off-by: Nicolas Ferre <[email protected]> Acked-by: Andy Shevchenko <[email protected]> Acked-by: Boris Brezillon <[email protected]>
2017-04-26srcu: Specify auto-expedite holdoff timePaul E. McKenney1-0/+8
On small systems, in the absence of readers, expedited SRCU grace periods can complete in less than a microsecond. This means that an eight-CPU system can have all CPUs doing synchronize_srcu() in a tight loop and almost always expedite. This might actually be desirable in some situations, but in general it is a good way to needlessly burn CPU cycles. And in those situations where it is desirable, your friend is the function synchronize_srcu_expedited(). For other situations, this commit adds a kernel parameter that specifies a holdoff between completing the last SRCU grace period and auto-expediting the next. If the next grace period starts before the holdoff expires, auto-expediting is disabled. The holdoff is 50 microseconds by default, and can be tuned to the desired number of nanoseconds. A value of zero disables auto-expediting. Signed-off-by: Paul E. McKenney <[email protected]> Tested-by: Mike Galbraith <[email protected]>
2017-04-26x86, iommu/vt-d: Add an option to disable Intel IOMMU force onShaohua Li1-0/+9
IOMMU harms performance signficantly when we run very fast networking workloads. It's 40GB networking doing XDP test. Software overhead is almost unaware, but it's the IOTLB miss (based on our analysis) which kills the performance. We observed the same performance issue even with software passthrough (identity mapping), only the hardware passthrough survives. The pps with iommu (with software passthrough) is only about ~30% of that without it. This is a limitation in hardware based on our observation, so we'd like to disable the IOMMU force on, but we do want to use TBOOT and we can sacrifice the DMA security bought by IOMMU. I must admit I know nothing about TBOOT, but TBOOT guys (cc-ed) think not eabling IOMMU is totally ok. So introduce a new boot option to disable the force on. It's kind of silly we need to run into intel_iommu_init even without force on, but we need to disable TBOOT PMR registers. For system without the boot option, nothing is changed. Signed-off-by: Shaohua Li <[email protected]> Signed-off-by: Joerg Roedel <[email protected]>
2017-04-20docs: process/4.Coding.rst: Fix a couple of document refsAndrew Clayton1-0/+2
In Documentation/process/4.Coding.rst there were a couple of paragraphs that spilled over the 80 character line length. This was likely caused when the document was converted to reStructuredText. Re-flow the paragraphs and make the document references proper reStructuredText :ref: links. This also adds the appropriate reStructuredText file heading to kernel-parameters.rst as referenced by the kernel-parameters link in this patch. Signed-off-by: Andrew Clayton <[email protected]> Reviewed-by: Jani Nikula <[email protected]> Signed-off-by: Jonathan Corbet <[email protected]>
2017-04-20nfs: remove the objlayout driverChristoph Hellwig1-6/+0
The objlayout code has been in the tree, but it's been unmaintained and no server product for it actually ever shipped. Signed-off-by: Christoph Hellwig <[email protected]> Signed-off-by: Trond Myklebust <[email protected]>
2017-04-07Merge branch 'for-joerg/arm-smmu/updates' of ↵Joerg Roedel1-0/+6
git://git.kernel.org/pub/scm/linux/kernel/git/will/linux into arm/smmu
2017-04-06iommu: Allow default domain type to be set on the kernel command lineWill Deacon1-0/+6
The IOMMU core currently initialises the default domain for each group to IOMMU_DOMAIN_DMA, under the assumption that devices will use IOMMU-backed DMA ops by default. However, in some cases it is desirable for the DMA ops to bypass the IOMMU for performance reasons, reserving use of translation for subsystems such as VFIO that require it for enforcing device isolation. Rather than modify each IOMMU driver to provide different semantics for DMA domains, instead we introduce a command line parameter that can be used to change the type of the default domain. Passthrough can then be specified using "iommu.passthrough=1" on the kernel command line. Signed-off-by: Will Deacon <[email protected]>
2017-03-31kasan: report only the first error by defaultMark Rutland1-0/+6
Disable kasan after the first report. There are several reasons for this: - Single bug quite often has multiple invalid memory accesses causing storm in the dmesg. - Write OOB access might corrupt metadata so the next report will print bogus alloc/free stacktraces. - Reports after the first easily could be not bugs by itself but just side effects of the first one. Given that multiple reports usually only do harm, it makes sense to disable kasan after the first one. If user wants to see all the reports, the boot-time parameter kasan_multi_shot must be used. [[email protected]: wrote changelog and doc, added missing include] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Mark Rutland <[email protected]> Signed-off-by: Andrey Ryabinin <[email protected]> Cc: Andrey Konovalov <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Dmitry Vyukov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-03-28RAS: Add a Corrected Errors CollectorBorislav Petkov1-0/+6
Introduce a simple data structure for collecting correctable errors along with accessors. More detailed description in the code itself. The error decoding is done with the decoding chain now and mce_first_notifier() gets to see the error first and the CEC decides whether to log it and then the rest of the chain doesn't hear about it - basically the main reason for the CE collector - or to continue running the notifiers. When the CEC hits the action threshold, it will try to soft-offine the page containing the ECC and then the whole decoding chain gets to see the error. Signed-off-by: Borislav Petkov <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: linux-edac <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>
2017-03-21x86/earlyprintk: Add support for earlyprintk via USB3 debug portLu Baolu1-0/+1
Add support for earlyprintk by writing debug messages to the USB3 debug port. Users can use this type of early printk by specifying the kernel parameter of "earlyprintk=xdbc". This gives users a chance of providing debugging output. The hardware for USB3 debug port requires DMA memory blocks. This requires to delay setting up debugging hardware and registering boot console until the memblocks are filled. Signed-off-by: Lu Baolu <[email protected]> Acked-by: Thomas Gleixner <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Mathias Nyman <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>
2017-03-16md: add sysfs entries for PPLArtur Paszkiewicz1-3/+29
Add 'consistency_policy' attribute for array. It indicates how the array maintains consistency in case of unexpected shutdown. Add 'ppl_sector' and 'ppl_size' for rdev, which describe the location and size of the PPL space on the device. They can't be changed for active members if the array is started and PPL is enabled, so in the setter functions only basic checks are performed. More checks are done in ppl_validate_rdev() when starting the log. These attributes are writable to allow enabling PPL for external metadata arrays and (later) to enable/disable PPL for a running array. Signed-off-by: Artur Paszkiewicz <[email protected]> Signed-off-by: Shaohua Li <[email protected]>
2017-03-14Documentation: admin-guide: Fix typosTamara Diaconita2-7/+7
Fix typos in admin-guide directory. Make documentation clear and grammatically correct. Signed-off-by: Tamara Diaconita <[email protected]> Signed-off-by: Jonathan Corbet <[email protected]>
2017-03-13Documentation: admin-guide: fix path to input key definitionsMartin Kepplinger1-1/+2
The UAPI header split failed to update the documentation here; fix things accordingly. Signed-off-by: Martin Kepplinger <[email protected]> Signed-off-by: Jonathan Corbet <[email protected]>
2017-03-13cpufreq: User/admin documentation update and consolidationRafael J. Wysocki3-0/+716
The user/admin documentation of cpufreq is badly outdated. It conains stale and/or inaccurate information along with things that are not particularly useful. Also, some of the important pieces are missing from it. For this reason, add a new user/admin document for cpufreq containing current information to admin-guide and drop the old outdated .txt documents it is replacing. Since there will be more PM documents in admin-guide going forward, create a separate directory for them and put the cpufreq document in there right away. Signed-off-by: Rafael J. Wysocki <[email protected]> Acked-by: Viresh Kumar <[email protected]> Signed-off-by: Jonathan Corbet <[email protected]>
2017-03-09Merge tag 'pm-4.11-rc2' of ↵Linus Torvalds1-0/+3
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management fixes from Rafael Wysocki: "These fix several issues in the intel_pstate driver and one issue in the schedutil cpufreq governor, clean up that governor a bit and hook up existing code for disabling cpufreq to a new kernel command line option. Specifics: - Three fixes for intel_pstate problems related to the passive mode (in which it acts as a regular cpufreq scaling driver), two for the handling of global P-state limits and one for the handling of the cpu_frequency tracepoint in that mode (Rafael Wysocki). - Three fixes for the handling of P-state limits in intel_pstate in the active mode (Rafael Wysocki). - Introduction of a new cpufreq.off=1 kernel command line argument that will disable cpufreq entirely if passed to the kernel and is simply hooked up to the existing code used by Xen (Len Brown). - Fix for the schedutil cpufreq governor to prevent it from using stale raw frequency values in configurations with mutiple CPUs sharing one policy object and a cleanup for it reducing its overhead slightly (Viresh Kumar)" * tag 'pm-4.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: cpufreq: intel_pstate: Do not reinit performance limits in ->setpolicy cpufreq: intel_pstate: Fix intel_pstate_verify_policy() cpufreq: intel_pstate: Fix global settings in active mode cpufreq: Add the "cpufreq.off=1" cmdline option cpufreq: schedutil: Pass sg_policy to get_next_freq() cpufreq: schedutil: move cached_raw_freq to struct sugov_policy cpufreq: intel_pstate: Avoid triggering cpu_frequency tracepoint unnecessarily cpufreq: intel_pstate: Fix intel_cpufreq_verify_policy() cpufreq: intel_pstate: Do not use performance_limits in passive mode
2017-03-09Merge branch 'pm-cpufreq'Rafael J. Wysocki1-0/+3
* pm-cpufreq: cpufreq: intel_pstate: Do not reinit performance limits in ->setpolicy cpufreq: intel_pstate: Fix intel_pstate_verify_policy() cpufreq: intel_pstate: Fix global settings in active mode cpufreq: Add the "cpufreq.off=1" cmdline option cpufreq: intel_pstate: Avoid triggering cpu_frequency tracepoint unnecessarily cpufreq: intel_pstate: Fix intel_cpufreq_verify_policy() cpufreq: intel_pstate: Do not use performance_limits in passive mode
2017-03-07Merge tag 'trace-v4.11-rc1' of ↵Linus Torvalds1-0/+6
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "There was some breakage with the changes for jump labels in the 4.11 merge window: - powerpc broke as jump labels uses the two LSB bits as flags in initialization. A check was added to make sure that all jump label entries were 4 bytes aligned, but powerpc didn't work that way for modules. Adding an alignment in the module linker script appeared to be the best solution. - Jump labels also added an anonymous union to access those LSB bits as a normal long. But because this structure had static initialization, it broke older compilers that could not statically initialize anonymous unions without brackets. - The command line parameter for setting function graph filter broke the "EMPTY_HASH" descriptor by modifying it instead of creating a new hash to hold the entries. - The command line parameter ftrace_graph_max_depth was added to allow its setting at boot time. It uses existing code and only the command line hook was added. This is not really a fix, but as it uses existing code without affecting anything else, I added it to this release. It was ready before the merge window closed, but I wanted to let it sit in linux-next for a couple of days first" * tag 'trace-v4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: ftrace/graph: Add ftrace_graph_max_depth kernel parameter tracing: Add #undef to fix compile error jump_label: Add comment about initialization order for anonymous unions jump_label: Fix anonymous union initialization module: set __jump_table alignment to 8 ftrace/graph: Do not modify the EMPTY_HASH for the function_graph filter tracing: Fix code comment for ftrace_ops_get_func()
2017-03-07docs: Clarify details for reporting security bugsKees Cook1-5/+34
The kernel security team is regularly asked to provide CVE identifiers, which we don't normally do. This updates the documentation to mention this and adds some more details about coordination and patch handling that come up regularly. Based on an earlier draft by Willy Tarreau. Signed-off-by: Kees Cook <[email protected]> Acked-by: Willy Tarreau <[email protected]> Signed-off-by: Jonathan Corbet <[email protected]>
2017-03-06HID: usbhid: extend polling interval configuration to joysticksTobias Jakobi1-0/+3
For mouse devices we can currently change the polling interval via usbhid.mousepoll. Implement the same thing for joysticks, so users can reduce input latency this way. This has been tested with a Logitech RumblePad 2 with jspoll=2, resulting in a polling rate of 500Hz (verified with evhz). Signed-off-by: Tobias Jakobi <[email protected]> Acked-by: Benjamin Tissoires <[email protected]> Signed-off-by: Jiri Kosina <[email protected]>
2017-03-06cpufreq: Add the "cpufreq.off=1" cmdline optionLen Brown1-0/+3
Add the "cpufreq.off=1" cmdline option. At boot-time, this allows a user to request CONFIG_CPU_FREQ=n behavior from a kernel built with CONFIG_CPU_FREQ=y. This is analogous to the existing "cpuidle.off=1" option and CONFIG_CPU_IDLE=y This capability is valuable when we need to debug end-user issues in the BIOS or in Linux. It is also convenient for enabling comparisons, which may otherwise require a new kernel, or help from BIOS SETUP, which may be buggy or unavailable. Signed-off-by: Len Brown <[email protected]> Signed-off-by: Rafael J. Wysocki <[email protected]>
2017-03-03ftrace/graph: Add ftrace_graph_max_depth kernel parameterTodd Brandt1-0/+6
Early trace callgraphs can be extremely large on systems with several seconds of boot time. The max_depth parameter limits how deep the graph trace goes and reduces the output size. This parameter is the same as the max_graph_depth file in tracefs. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Todd Brandt <[email protected]> [ changed comments about debugfs to tracefs ] Signed-off-by: Steven Rostedt (VMware) <[email protected]>