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2020-04-12Merge tag 'timers-urgent-2020-04-12' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull time(keeping) updates from Thomas Gleixner: - Fix the time_for_children symlink in /proc/$PID/ so it properly reflects that it part of the 'time' namespace - Add the missing userns limit for the allowed number of time namespaces, which was half defined but the actual array member was not added. This went unnoticed as the array has an exessive empty member at the end but introduced a user visible regression as the output was corrupted. - Prevent further silent ucount corruption by adding a BUILD_BUG_ON() to catch half updated data. * tag 'timers-urgent-2020-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: ucount: Make sure ucounts in /proc/sys/user don't regress again time/namespace: Add max_time_namespaces ucount time/namespace: Fix time_for_children symlink
2020-04-10Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge yet more updates from Andrew Morton: - Almost all of the rest of MM (memcg, slab-generic, slab, pagealloc, gup, hugetlb, pagemap, memremap) - Various other things (hfs, ocfs2, kmod, misc, seqfile) * akpm: (34 commits) ipc/util.c: sysvipc_find_ipc() should increase position index kernel/gcov/fs.c: gcov_seq_next() should increase position index fs/seq_file.c: seq_read(): add info message about buggy .next functions drivers/dma/tegra20-apb-dma.c: fix platform_get_irq.cocci warnings change email address for Pali Rohár selftests: kmod: test disabling module autoloading selftests: kmod: fix handling test numbers above 9 docs: admin-guide: document the kernel.modprobe sysctl fs/filesystems.c: downgrade user-reachable WARN_ONCE() to pr_warn_once() kmod: make request_module() return an error when autoloading is disabled mm/memremap: set caching mode for PCI P2PDMA memory to WC mm/memory_hotplug: add pgprot_t to mhp_params powerpc/mm: thread pgprot_t through create_section_mapping() x86/mm: introduce __set_memory_prot() x86/mm: thread pgprot_t through init_memory_mapping() mm/memory_hotplug: rename mhp_restrictions to mhp_params mm/memory_hotplug: drop the flags field from struct mhp_restrictions mm/special: create generic fallbacks for pte_special() and pte_mkspecial() mm/vma: introduce VM_ACCESS_FLAGS mm/vma: define a default value for VM_DATA_DEFAULT_FLAGS ...
2020-04-10Merge tag 'docs-5.7-2' of git://git.lwn.net/linuxLinus Torvalds
Pull Documentation fixes from Jonathan Corbet: "A handful of late-arriving fixes for the documentation tree" * tag 'docs-5.7-2' of git://git.lwn.net/linux: Documentation: android: binderfs: add 'stats' mount option Documentation: driver-api/usb/writing_usb_driver.rst Updates documentation links docs: driver-api: address duplicate label warning Documentation: sysrq: fix RST formatting docs: kernel-parameters.txt: Fix broken references docs: kernel-parameters.txt: Remove nompx docs: filesystems: fix typo in qnx6.rst
2020-04-10docs: admin-guide: document the kernel.modprobe sysctlEric Biggers
Document the kernel.modprobe sysctl in the same place that all the other kernel.* sysctls are documented. Make sure to mention how to use this sysctl to completely disable module autoloading, and how this sysctl relates to CONFIG_STATIC_USERMODEHELPER. [ebiggers@google.com: v5] Link: http://lkml.kernel.org/r/20200318230515.171692-4-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jeff Vander Stoep <jeffv@google.com> Cc: Jessica Yu <jeyu@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: NeilBrown <neilb@suse.com> Link: http://lkml.kernel.org/r/20200312202552.241885-4-ebiggers@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10mm: hugetlb: optionally allocate gigantic hugepages using cmaRoman Gushchin
Commit 944d9fec8d7a ("hugetlb: add support for gigantic page allocation at runtime") has added the run-time allocation of gigantic pages. However it actually works only at early stages of the system loading, when the majority of memory is free. After some time the memory gets fragmented by non-movable pages, so the chances to find a contiguous 1GB block are getting close to zero. Even dropping caches manually doesn't help a lot. At large scale rebooting servers in order to allocate gigantic hugepages is quite expensive and complex. At the same time keeping some constant percentage of memory in reserved hugepages even if the workload isn't using it is a big waste: not all workloads can benefit from using 1 GB pages. The following solution can solve the problem: 1) On boot time a dedicated cma area* is reserved. The size is passed as a kernel argument. 2) Run-time allocations of gigantic hugepages are performed using the cma allocator and the dedicated cma area In this case gigantic hugepages can be allocated successfully with a high probability, however the memory isn't completely wasted if nobody is using 1GB hugepages: it can be used for pagecache, anon memory, THPs, etc. * On a multi-node machine a per-node cma area is allocated on each node. Following gigantic hugetlb allocation are using the first available numa node if the mask isn't specified by a user. Usage: 1) configure the kernel to allocate a cma area for hugetlb allocations: pass hugetlb_cma=10G as a kernel argument 2) allocate hugetlb pages as usual, e.g. echo 10 > /sys/kernel/mm/hugepages/hugepages-1048576kB/nr_hugepages If the option isn't enabled or the allocation of the cma area failed, the current behavior of the system is preserved. x86 and arm-64 are covered by this patch, other architectures can be trivially added later. The patch contains clean-ups and fixes proposed and implemented by Aslan Bakirov and Randy Dunlap. It also contains ideas and suggestions proposed by Rik van Riel, Michal Hocko and Mike Kravetz. Thanks! Signed-off-by: Roman Gushchin <guro@fb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Andreas Schaufler <andreas.schaufler@gmx.de> Acked-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: Michal Hocko <mhocko@kernel.org> Cc: Aslan Bakirov <aslan@fb.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Rik van Riel <riel@surriel.com> Cc: Joonsoo Kim <js1304@gmail.com> Link: http://lkml.kernel.org/r/20200407163840.92263-3-guro@fb.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10Documentation: android: binderfs: add 'stats' mount optionRandy Dunlap
Add documentation of the binderfs 'stats' mount option. Description taken from the commit message. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Link: https://lore.kernel.org/r/baa0aa81-007d-af46-16a5-91fead0bd1b9@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-04-07Documentation: sysrq: fix RST formattingAlyssa Ross
"On x86" and "On SPARC" are now definition list terms, like "On PowerPC", "On other", and "On all". The Credits list is now a bulleted list, like lots of Credits lists in other files. This prevents the list from becoming a single long, unpunctuated sentence in the generated documentation. I also did a couple of other tiny readability improvements to the "How do I use the magic SysRq key?" section while I was there. Signed-off-by: Alyssa Ross <hi@alyssa.is> Link: https://lore.kernel.org/r/20200403170701.10852-1-hi@alyssa.is Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-04-07docs: kernel-parameters.txt: Fix broken referencesJimmy Assarsson
Fix remaining broken references in kernel-parameters.txt. Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Jimmy Assarsson <jimmyassarsson@gmail.com> Link: https://lore.kernel.org/r/20200402172614.3020-2-jimmyassarsson@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-04-07docs: kernel-parameters.txt: Remove nompxJimmy Assarsson
x86/mpx was removed in commit 45fc24e89b7c ("x86/mpx: remove MPX from arch/x86"), this removes the documentation of parameter nompx. Fixes: 45fc24e89b7c ("x86/mpx: remove MPX from arch/x86") Signed-off-by: Jimmy Assarsson <jimmyassarsson@gmail.com> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lore.kernel.org/r/20200402172614.3020-1-jimmyassarsson@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-04-07mm/memory_hotplug.c: only respect mem= parameter during boot stageBaoquan He
In commit 357b4da50a62 ("x86: respect memory size limiting via mem= parameter") a global varialbe max_mem_size is added to store the value parsed from 'mem= ', then checked when memory region is added. This truly stops those DIMMs from being added into system memory during boot-time. However, it also limits the later memory hotplug functionality. Any DIMM can't be hotplugged any more if its region is beyond the max_mem_size. We will get errors like: [ 216.387164] acpi PNP0C80:02: add_memory failed [ 216.389301] acpi PNP0C80:02: acpi_memory_enable_device() error [ 216.392187] acpi PNP0C80:02: Enumeration failure This will cause issue in a known use case where 'mem=' is added to the hypervisor. The memory that lies after 'mem=' boundary will be assigned to KVM guests. After commit 357b4da50a62 merged, memory can't be extended dynamically if system memory on hypervisor is not sufficient. So fix it by also checking if it's during boot-time restricting to add memory. Otherwise, skip the restriction. And also add this use case to document of 'mem=' kernel parameter. Fixes: 357b4da50a62 ("x86: respect memory size limiting via mem= parameter") Signed-off-by: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Juergen Gross <jgross@suse.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: William Kucharski <william.kucharski@oracle.com> Cc: David Hildenbrand <david@redhat.com> Cc: Balbir Singh <bsingharora@gmail.com> Link: http://lkml.kernel.org/r/20200204050643.20925-1-bhe@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07userfaultfd: wp: UFFDIO_REGISTER_MODE_WP documentation updateMartin Cracauer
Add documentation about the write protection support. [peterx@redhat.com: rewrite in rst format; fixups here and there] Signed-off-by: Martin Cracauer <cracauer@cons.org> Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Jerome Glisse <jglisse@redhat.com> Reviewed-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Bobby Powers <bobbypowers@gmail.com> Cc: Brian Geffon <bgeffon@google.com> Cc: David Hildenbrand <david@redhat.com> Cc: Denis Plotnikov <dplotnikov@virtuozzo.com> Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: "Kirill A . Shutemov" <kirill@shutemov.name> Cc: Marty McFadden <mcfadden8@llnl.gov> Cc: Maya Gokhale <gokhale2@llnl.gov> Cc: Mel Gorman <mgorman@suse.de> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Pavel Emelyanov <xemul@openvz.org> Cc: Rik van Riel <riel@redhat.com> Cc: Shaohua Li <shli@fb.com> Link: http://lkml.kernel.org/r/20200220163112.11409-17-peterx@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07mm, thp: track fallbacks due to failed memcg charges separatelyDavid Rientjes
The thp_fault_fallback and thp_file_fallback vmstats are incremented if either the hugepage allocation fails through the page allocator or the hugepage charge fails through mem cgroup. This patch leaves this field untouched but adds two new fields, thp_{fault,file}_fallback_charge, which is incremented only when the mem cgroup charge fails. This distinguishes between attempted hugepage allocations that fail due to fragmentation (or low memory conditions) and those that fail due to mem cgroup limits. That can be used to determine the impact of fragmentation on the system by excluding faults that failed due to memcg usage. Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Yang Shi <yang.shi@linux.alibaba.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Jeremy Cline <jcline@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Link: http://lkml.kernel.org/r/alpine.DEB.2.21.2003061422070.7412@chino.kir.corp.google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07mm, shmem: add vmstat for hugepage fallbackDavid Rientjes
The existing thp_fault_fallback indicates when thp attempts to allocate a hugepage but fails, or if the hugepage cannot be charged to the mem cgroup hierarchy. Extend this to shmem as well. Adds a new thp_file_fallback to complement thp_file_alloc that gets incremented when a hugepage is attempted to be allocated but fails, or if it cannot be charged to the mem cgroup hierarchy. Additionally, remove the check for CONFIG_TRANSPARENT_HUGE_PAGECACHE from shmem_alloc_hugepage() since it is only called with this configuration option. Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Yang Shi <yang.shi@linux.alibaba.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Jeremy Cline <jcline@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Link: http://lkml.kernel.org/r/alpine.DEB.2.21.2003061421240.7412@chino.kir.corp.google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07time/namespace: Add max_time_namespaces ucountDmitry Safonov
Michael noticed that userns limit for number of time namespaces is missing. Furthermore, time namespace introduced UCOUNT_TIME_NAMESPACES, but didn't introduce an array member in user_table[]. It would make array's initialisation OOB write, but by luck the user_table array has an excessive empty member (all accesses to the array are limited with UCOUNT_COUNTS - so it silently reuses the last free member. Fixes user-visible regression: max_inotify_instances by reason of the missing UCOUNT_ENTRY() has limited max number of namespaces instead of the number of inotify instances. Fixes: 769071ac9f20 ("ns: Introduce Time Namespace") Reported-by: Michael Kerrisk (man-pages) <mtk.manpages@gmail.com> Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Andrei Vagin <avagin@gmail.com> Acked-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: stable@kernel.org Link: https://lkml.kernel.org/r/20200406171342.128733-1-dima@arista.com
2020-04-06Merge tag 'acpi-5.7-rc1-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more ACPI updates from Rafael Wysocki: "Additional ACPI updates. These update the ACPICA code in the kernel to the 20200326 upstream revision, fix an ACPI-related CPU hotplug deadlock on x86, update Intel Tiger Lake device IDs in some places, add a new ACPI backlight blacklist entry, update the "acpi_backlight" kernel command line switch documentation and clean up a CPPC library routine. Specifics: - Update the ACPICA code in the kernel to upstream revision 20200326 including: * Fix for a typo in a comment field (Bob Moore) * acpiExec namespace init file fixes (Bob Moore) * Addition of NHLT to the known tables list (Cezary Rojewski) * Conversion of PlatformCommChannel ASL keyword to PCC (Erik Kaneda) * acpiexec cleanup (Erik Kaneda) * WSMT-related typo fix (Erik Kaneda) * sprintf() utility function fix (John Levon) * IVRS IVHD type 11h parsing implementation (Michał Żygowski) * IVRS IVHD type 10h reserved field name fix (Michał Żygowski) - Fix ACPI-related CPU hotplug deadlock on x86 (Qian Cai) - Fix Intel Tiger Lake ACPI device IDs in several places (Gayatri Kammela) - Add ACPI backlight blacklist entry for Acer Aspire 5783z (Hans de Goede) - Fix documentation of the "acpi_backlight" kernel command line switch (Randy Dunlap) - Clean up the acpi_get_psd_map() CPPC library routine (Liguang Zhang)" * tag 'acpi-5.7-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: x86: ACPI: fix CPU hotplug deadlock thermal: int340x_thermal: fix: Update Tiger Lake ACPI device IDs platform/x86: intel-hid: fix: Update Tiger Lake ACPI device ID ACPI: Update Tiger Lake ACPI device IDs ACPI: video: Use native backlight on Acer Aspire 5783z ACPI: video: Docs update for "acpi_backlight" kernel parameter options ACPICA: Update version 20200326 ACPICA: Fixes for acpiExec namespace init file ACPICA: Add NHLT table signature ACPICA: WSMT: Fix typo, no functional change ACPICA: utilities: fix sprintf() ACPICA: acpiexec: remove redeclaration of acpi_gbl_db_opt_no_region_support ACPICA: Change PlatformCommChannel ASL keyword to PCC ACPICA: Fix IVRS IVHD type 10h reserved field name ACPICA: Implement IVRS IVHD type 11h parsing ACPICA: Fix a typo in a comment field ACPI: CPPC: clean up acpi_get_psd_map()
2020-04-06Merge tag 'pm-5.7-rc1-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more power management updates from Rafael Wysocki: "Additional power management updates. These fix a corner-case suspend-to-idle wakeup issue on systems where the ACPI SCI is shared with another wakeup source, add a kernel command line option to set pm_debug_messages via the kernel command line, add a document desctibing system-wide suspend and resume code flows, modify cpufreq Kconfig to choose schedutil as the preferred governor by default in a couple of cases and do some assorted cleanups. Specifics: - Fix corner-case suspend-to-idle wakeup issue on systems where the ACPI SCI is shared with another wakeup source (Hans de Goede). - Add document describing system-wide suspend and resume code flows to the admin guide (Rafael Wysocki). - Add kernel command line option to set pm_debug_messages (Chen Yu). - Choose schedutil as the preferred scaling governor by default on ARM big.LITTLE systems and on x86 systems using the intel_pstate driver in the passive mode (Linus Walleij, Rafael Wysocki). - Drop racy and redundant checks from the PM core's device_prepare() routine (Rafael Wysocki). - Make resume from hibernation take the hibernation_restore() return value into account (Dexuan Cui)" * tag 'pm-5.7-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: platform/x86: intel_int0002_vgpio: Use acpi_register_wakeup_handler() ACPI: PM: Add acpi_[un]register_wakeup_handler() Documentation: PM: sleep: Document system-wide suspend code flows cpufreq: Select schedutil when using big.LITTLE PM: sleep: Add pm_debug_messages kernel command line option PM: sleep: core: Drop racy and redundant checks from device_prepare() PM: hibernate: Propagate the return value of hibernation_restore() cpufreq: intel_pstate: Select schedutil as the default governor
2020-04-03Merge tag 'char-misc-5.7-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc driver updates from Greg KH: "Here is the big set of char/misc/other driver patches for 5.7-rc1. Lots of things in here, and it's later than expected due to some reverts to resolve some reported issues. All is now clean with no reported problems in linux-next. Included in here is: - interconnect updates - mei driver updates - uio updates - nvmem driver updates - soundwire updates - binderfs updates - coresight updates - habanalabs updates - mhi new bus type and core - extcon driver updates - some Kconfig cleanups - other small misc driver cleanups and updates As mentioned, all have been in linux-next for a while, and with the last two reverts, all is calm and good" * tag 'char-misc-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (174 commits) Revert "driver core: platform: Initialize dma_parms for platform devices" Revert "amba: Initialize dma_parms for amba devices" amba: Initialize dma_parms for amba devices driver core: platform: Initialize dma_parms for platform devices bus: mhi: core: Drop the references to mhi_dev in mhi_destroy_device() bus: mhi: core: Initialize bhie field in mhi_cntrl for RDDM capture bus: mhi: core: Add support for reading MHI info from device misc: rtsx: set correct pcr_ops for rts522A speakup: misc: Use dynamic minor numbers for speakup devices mei: me: add cedar fork device ids coresight: do not use the BIT() macro in the UAPI header Documentation: provide IBM contacts for embargoed hardware nvmem: core: remove nvmem_sysfs_get_groups() nvmem: core: use is_bin_visible for permissions nvmem: core: use device_register and device_unregister nvmem: core: add root_only member to nvmem device struct extcon: axp288: Add wakeup support extcon: Mark extcon_get_edev_name() function as exported symbol extcon: palmas: Hide error messages if gpio returns -EPROBE_DEFER dt-bindings: extcon: usbc-cros-ec: convert extcon-usbc-cros-ec.txt to yaml format ...
2020-04-03Merge branch 'for-5.7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup updates from Tejun Heo: - Christian extended clone3 so that processes can be spawned into cgroups directly. This is not only neat in terms of semantics but also avoids grabbing the global cgroup_threadgroup_rwsem for migration. - Daniel added !root xattr support to cgroupfs. Userland already uses xattrs on cgroupfs for bookkeeping. This will allow delegated cgroups to support such usages. - Prateek tried to make cpuset hotplug handling synchronous but that led to possible deadlock scenarios. Reverted. - Other minor changes including release_agent_path handling cleanup. * 'for-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: docs: cgroup-v1: Document the cpuset_v2_mode mount option Revert "cpuset: Make cpuset hotplug synchronous" cgroupfs: Support user xattrs kernfs: Add option to enable user xattrs kernfs: Add removed_size out param for simple_xattr_set kernfs: kvmalloc xattr value instead of kmalloc cgroup: Restructure release_agent_path handling selftests/cgroup: add tests for cloning into cgroups clone3: allow spawning processes into cgroups cgroup: add cgroup_may_write() helper cgroup: refactor fork helpers cgroup: add cgroup_get_from_file() helper cgroup: unify attach permission checking cpuset: Make cpuset hotplug synchronous cgroup.c: Use built-in RCU list checking kselftest/cgroup: add cgroup destruction test cgroup: Clean up css_set task traversal
2020-04-03docs: cgroup-v1: Document the cpuset_v2_mode mount optionWaiman Long
The cpuset in cgroup v1 accepts a special "cpuset_v2_mode" mount option that make cpuset.cpus and cpuset.mems behave more like those in cgroup v2. Document it to make other people more aware of this feature that can be useful in some circumstances. Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2020-04-03Documentation: PM: sleep: Document system-wide suspend code flowsRafael J. Wysocki
Add a document describing high-level system-wide suspend code flows in Linux. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-04-02Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm updates from Paolo Bonzini: "ARM: - GICv4.1 support - 32bit host removal PPC: - secure (encrypted) using under the Protected Execution Framework ultravisor s390: - allow disabling GISA (hardware interrupt injection) and protected VMs/ultravisor support. x86: - New dirty bitmap flag that sets all bits in the bitmap when dirty page logging is enabled; this is faster because it doesn't require bulk modification of the page tables. - Initial work on making nested SVM event injection more similar to VMX, and less buggy. - Various cleanups to MMU code (though the big ones and related optimizations were delayed to 5.8). Instead of using cr3 in function names which occasionally means eptp, KVM too has standardized on "pgd". - A large refactoring of CPUID features, which now use an array that parallels the core x86_features. - Some removal of pointer chasing from kvm_x86_ops, which will also be switched to static calls as soon as they are available. - New Tigerlake CPUID features. - More bugfixes, optimizations and cleanups. Generic: - selftests: cleanups, new MMU notifier stress test, steal-time test - CSV output for kvm_stat" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (277 commits) x86/kvm: fix a missing-prototypes "vmread_error" KVM: x86: Fix BUILD_BUG() in __cpuid_entry_get_reg() w/ CONFIG_UBSAN=y KVM: VMX: Add a trampoline to fix VMREAD error handling KVM: SVM: Annotate svm_x86_ops as __initdata KVM: VMX: Annotate vmx_x86_ops as __initdata KVM: x86: Drop __exit from kvm_x86_ops' hardware_unsetup() KVM: x86: Copy kvm_x86_ops by value to eliminate layer of indirection KVM: x86: Set kvm_x86_ops only after ->hardware_setup() completes KVM: VMX: Configure runtime hooks using vmx_x86_ops KVM: VMX: Move hardware_setup() definition below vmx_x86_ops KVM: x86: Move init-only kvm_x86_ops to separate struct KVM: Pass kvm_init()'s opaque param to additional arch funcs s390/gmap: return proper error code on ksm unsharing KVM: selftests: Fix cosmetic copy-paste error in vm_mem_region_move() KVM: Fix out of range accesses to memslots KVM: X86: Micro-optimize IPI fastpath delay KVM: X86: Delay read msr data iff writes ICR MSR KVM: PPC: Book3S HV: Add a capability for enabling secure guests KVM: arm64: GICv4.1: Expose HW-based SGIs in debugfs KVM: arm64: GICv4.1: Allow non-trapping WFI when using HW SGIs ...
2020-04-02Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge updates from Andrew Morton: "A large amount of MM, plenty more to come. Subsystems affected by this patch series: - tools - kthread - kbuild - scripts - ocfs2 - vfs - mm: slub, kmemleak, pagecache, gup, swap, memcg, pagemap, mremap, sparsemem, kasan, pagealloc, vmscan, compaction, mempolicy, hugetlbfs, hugetlb" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (155 commits) include/linux/huge_mm.h: check PageTail in hpage_nr_pages even when !THP mm/hugetlb: fix build failure with HUGETLB_PAGE but not HUGEBTLBFS selftests/vm: fix map_hugetlb length used for testing read and write mm/hugetlb: remove unnecessary memory fetch in PageHeadHuge() mm/hugetlb.c: clean code by removing unnecessary initialization hugetlb_cgroup: add hugetlb_cgroup reservation docs hugetlb_cgroup: add hugetlb_cgroup reservation tests hugetlb: support file_region coalescing again hugetlb_cgroup: support noreserve mappings hugetlb_cgroup: add accounting for shared mappings hugetlb: disable region_add file_region coalescing hugetlb_cgroup: add reservation accounting for private mappings mm/hugetlb_cgroup: fix hugetlb_cgroup migration hugetlb_cgroup: add interface for charge/uncharge hugetlb reservations hugetlb_cgroup: add hugetlb_cgroup reservation counter hugetlbfs: Use i_mmap_rwsem to address page fault/truncate race hugetlbfs: use i_mmap_rwsem for more pmd sharing synchronization mm/memblock.c: remove redundant assignment to variable max_addr mm: mempolicy: require at least one nodeid for MPOL_PREFERRED mm: mempolicy: use VM_BUG_ON_VMA in queue_pages_test_walk() ...
2020-04-02hugetlb_cgroup: add hugetlb_cgroup reservation docsMina Almasry
Add docs for how to use hugetlb_cgroup reservations, and their behavior. Signed-off-by: Mina Almasry <almasrymina@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: David Rientjes <rientjes@google.com> Cc: Greg Thelen <gthelen@google.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Sandipan Das <sandipan@linux.ibm.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Shuah Khan <shuah@kernel.org> Link: http://lkml.kernel.org/r/20200211213128.73302-9-almasrymina@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02mm/compaction: Disable compact_unevictable_allowed on RTSebastian Andrzej Siewior
Since commit 5bbe3547aa3ba ("mm: allow compaction of unevictable pages") it is allowed to examine mlocked pages and compact them by default. On -RT even minor pagefaults are problematic because it may take a few 100us to resolve them and until then the task is blocked. Make compact_unevictable_allowed = 0 default and issue a warning on RT if it is changed. [bigeasy@linutronix.de: v5] Link: https://lore.kernel.org/linux-mm/20190710144138.qyn4tuttdq6h7kqx@linutronix.de/ Link: http://lkml.kernel.org/r/20200319165536.ovi75tsr2seared4@linutronix.de Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Iurii Zaikin <yzaikin@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Link: https://lore.kernel.org/linux-mm/20190710144138.qyn4tuttdq6h7kqx@linutronix.de/ Link: http://lkml.kernel.org/r/20200303202225.nhqc3v5gwlb7x6et@linutronix.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02mm: memcontrol: recursive memory.low protectionJohannes Weiner
Right now, the effective protection of any given cgroup is capped by its own explicit memory.low setting, regardless of what the parent says. The reasons for this are mostly historical and ease of implementation: to make delegation of memory.low safe, effective protection is the min() of all memory.low up the tree. Unfortunately, this limitation makes it impossible to protect an entire subtree from another without forcing the user to make explicit protection allocations all the way to the leaf cgroups - something that is highly undesirable in real life scenarios. Consider memory in a data center host. At the cgroup top level, we have a distinction between system management software and the actual workload the system is executing. Both branches are further subdivided into individual services, job components etc. We want to protect the workload as a whole from the system management software, but that doesn't mean we want to protect and prioritize individual workload wrt each other. Their memory demand can vary over time, and we'd want the VM to simply cache the hottest data within the workload subtree. Yet, the current memory.low limitations force us to allocate a fixed amount of protection to each workload component in order to get protection from system management software in general. This results in very inefficient resource distribution. Another concern with mandating downward allocation is that, as the complexity of the cgroup tree grows, it gets harder for the lower levels to be informed about decisions made at the host-level. Consider a container inside a namespace that in turn creates its own nested tree of cgroups to run multiple workloads. It'd be extremely difficult to configure memory.low parameters in those leaf cgroups that on one hand balance pressure among siblings as the container desires, while also reflecting the host-level protection from e.g. rpm upgrades, that lie beyond one or more delegation and namespacing points in the tree. It's highly unusual from a cgroup interface POV that nested levels have to be aware of and reflect decisions made at higher levels for them to be effective. To enable such use cases and scale configurability for complex trees, this patch implements a resource inheritance model for memory that is similar to how the CPU and the IO controller implement work-conserving resource allocations: a share of a resource allocated to a subree always applies to the entire subtree recursively, while allowing, but not mandating, children to further specify distribution rules. That means that if protection is explicitly allocated among siblings, those configured shares are being followed during page reclaim just like they are now. However, if the memory.low set at a higher level is not fully claimed by the children in that subtree, the "floating" remainder is applied to each cgroup in the tree in proportion to its size. Since reclaim pressure is applied in proportion to size as well, each child in that tree gets the same boost, and the effect is neutral among siblings - with respect to each other, they behave as if no memory control was enabled at all, and the VM simply balances the memory demands optimally within the subtree. But collectively those cgroups enjoy a boost over the cgroups in neighboring trees. E.g. a leaf cgroup with a memory.low setting of 0 no longer means that it's not getting a share of the hierarchically assigned resource, just that it doesn't claim a fixed amount of it to protect from its siblings. This allows us to recursively protect one subtree (workload) from another (system management), while letting subgroups compete freely among each other - without having to assign fixed shares to each leaf, and without nested groups having to echo higher-level settings. The floating protection composes naturally with fixed protection. Consider the following example tree: A A: low = 2G / \ A1: low = 1G A1 A2 A2: low = 0G As outside pressure is applied to this tree, A1 will enjoy a fixed protection from A2 of 1G, but the remaining, unclaimed 1G from A is split evenly among A1 and A2, coming out to 1.5G and 0.5G. There is a slight risk of regressing theoretical setups where the top-level cgroups don't know about the true budgeting and set bogusly high "bypass" values that are meaningfully allocated down the tree. Such setups would rely on unclaimed protection to be discarded, and distributing it would change the intended behavior. Be safe and hide the new behavior behind a mount option, 'memory_recursiveprot'. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Roman Gushchin <guro@fb.com> Acked-by: Chris Down <chris@chrisdown.name> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Link: http://lkml.kernel.org/r/20200227195606.46212-4-hannes@cmpxchg.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02PM: sleep: Add pm_debug_messages kernel command line optionChen Yu
Debug messages from the system suspend/hibernation infrastructure are disabled by default, and can only be enabled after the system has boot up via /sys/power/pm_debug_messages. This makes the hibernation resume hard to track as it involves system boot up across hibernation. There's no chance for software_resume() to track the resume process, for example. Add a kernel command line option to set pm_debug_messages during boot up. Signed-off-by: Chen Yu <yu.c.chen@intel.com> [ rjw: Subject & changelog ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-04-01Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree updates from Jiri Kosina: "My attempt to revitalize trivial queue I've been neglecting for years (what a disaster that was for this world, right? :) ) with patches collected from backlog that were still relevant and not applied elsewhere in the meantime" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: err.h: remove deprecated PTR_RET for good blk-mq: Fix typo in comment x86/boot: Fix comment spelling sh: mach-highlander: Fix comment spelling s390/dasd: Fix comment spelling mfd: wm8994: Fix comment spelling docs: Add reference in binfmt-misc.rst genirq: fix kerneldoc comment for irq_desc drm/amdgpu: fix two documentation mismatch issues HID: fix Kconfig word ordering list/hashtable: minor documentation corrections.
2020-04-01ACPI: video: Docs update for "acpi_backlight" kernel parameter optionsRandy Dunlap
Update the Documentation for "acpi_backlight" by adding 2 new options (native and none). Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-31Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextLinus Torvalds
Pull networking updates from David Miller: "Highlights: 1) Fix the iwlwifi regression, from Johannes Berg. 2) Support BSS coloring and 802.11 encapsulation offloading in hardware, from John Crispin. 3) Fix some potential Spectre issues in qtnfmac, from Sergey Matyukevich. 4) Add TTL decrement action to openvswitch, from Matteo Croce. 5) Allow paralleization through flow_action setup by not taking the RTNL mutex, from Vlad Buslov. 6) A lot of zero-length array to flexible-array conversions, from Gustavo A. R. Silva. 7) Align XDP statistics names across several drivers for consistency, from Lorenzo Bianconi. 8) Add various pieces of infrastructure for offloading conntrack, and make use of it in mlx5 driver, from Paul Blakey. 9) Allow using listening sockets in BPF sockmap, from Jakub Sitnicki. 10) Lots of parallelization improvements during configuration changes in mlxsw driver, from Ido Schimmel. 11) Add support to devlink for generic packet traps, which report packets dropped during ACL processing. And use them in mlxsw driver. From Jiri Pirko. 12) Support bcmgenet on ACPI, from Jeremy Linton. 13) Make BPF compatible with RT, from Thomas Gleixnet, Alexei Starovoitov, and your's truly. 14) Support XDP meta-data in virtio_net, from Yuya Kusakabe. 15) Fix sysfs permissions when network devices change namespaces, from Christian Brauner. 16) Add a flags element to ethtool_ops so that drivers can more simply indicate which coalescing parameters they actually support, and therefore the generic layer can validate the user's ethtool request. Use this in all drivers, from Jakub Kicinski. 17) Offload FIFO qdisc in mlxsw, from Petr Machata. 18) Support UDP sockets in sockmap, from Lorenz Bauer. 19) Fix stretch ACK bugs in several TCP congestion control modules, from Pengcheng Yang. 20) Support virtual functiosn in octeontx2 driver, from Tomasz Duszynski. 21) Add region operations for devlink and use it in ice driver to dump NVM contents, from Jacob Keller. 22) Add support for hw offload of MACSEC, from Antoine Tenart. 23) Add support for BPF programs that can be attached to LSM hooks, from KP Singh. 24) Support for multiple paths, path managers, and counters in MPTCP. From Peter Krystad, Paolo Abeni, Florian Westphal, Davide Caratti, and others. 25) More progress on adding the netlink interface to ethtool, from Michal Kubecek" * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2121 commits) net: ipv6: rpl_iptunnel: Fix potential memory leak in rpl_do_srh_inline cxgb4/chcr: nic-tls stats in ethtool net: dsa: fix oops while probing Marvell DSA switches net/bpfilter: remove superfluous testing message net: macb: Fix handling of fixed-link node net: dsa: ksz: Select KSZ protocol tag netdevsim: dev: Fix memory leak in nsim_dev_take_snapshot_write net: stmmac: add EHL 2.5Gbps PCI info and PCI ID net: stmmac: add EHL PSE0 & PSE1 1Gbps PCI info and PCI ID net: stmmac: create dwmac-intel.c to contain all Intel platform net: dsa: bcm_sf2: Support specifying VLAN tag egress rule net: dsa: bcm_sf2: Add support for matching VLAN TCI net: dsa: bcm_sf2: Move writing of CFP_DATA(5) into slicing functions net: dsa: bcm_sf2: Check earlier for FLOW_EXT and FLOW_MAC_EXT net: dsa: bcm_sf2: Disable learning for ASP port net: dsa: b53: Deny enslaving port 7 for 7278 into a bridge net: dsa: b53: Prevent tagged VLAN on port 7 for 7278 net: dsa: b53: Restore VLAN entries upon (re)configuration net: dsa: bcm_sf2: Fix overflow checks hv_netvsc: Remove unnecessary round_up for recv_completion_cnt ...
2020-03-31Merge tag 'selinux-pr-20200330' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull SELinux updates from Paul Moore: "We've got twenty SELinux patches for the v5.7 merge window, the highlights are below: - Deprecate setting /sys/fs/selinux/checkreqprot to 1. This flag was originally created to deal with legacy userspace and the READ_IMPLIES_EXEC personality flag. We changed the default from 1 to 0 back in Linux v4.4 and now we are taking the next step of deprecating it, at some point in the future we will take the final step of rejecting 1. - Allow kernfs symlinks to inherit the SELinux label of the parent directory. In order to preserve backwards compatibility this is protected by the genfs_seclabel_symlinks SELinux policy capability. - Optimize how we store filename transitions in the kernel, resulting in some significant improvements to policy load times. - Do a better job calculating our internal hash table sizes which resulted in additional policy load improvements and likely general SELinux performance improvements as well. - Remove the unused initial SIDs (labels) and improve how we handle initial SIDs. - Enable per-file labeling for the bpf filesystem. - Ensure that we properly label NFS v4.2 filesystems to avoid a temporary unlabeled condition. - Add some missing XFS quota command types to the SELinux quota access controls. - Fix a problem where we were not updating the seq_file position index correctly in selinuxfs. - We consolidate some duplicated code into helper functions. - A number of list to array conversions. - Update Stephen Smalley's email address in MAINTAINERS" * tag 'selinux-pr-20200330' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: selinux: clean up indentation issue with assignment statement NFS: Ensure security label is set for root inode MAINTAINERS: Update my email address selinux: avtab_init() and cond_policydb_init() return void selinux: clean up error path in policydb_init() selinux: remove unused initial SIDs and improve handling selinux: reduce the use of hard-coded hash sizes selinux: Add xfs quota command types selinux: optimize storage of filename transitions selinux: factor out loop body from filename_trans_read() security: selinux: allow per-file labeling for bpffs selinux: generalize evaluate_cond_node() selinux: convert cond_expr to array selinux: convert cond_av_list to array selinux: convert cond_list to array selinux: sel_avc_get_stat_idx should increase position index selinux: allow kernfs symlinks to inherit parent directory context selinux: simplify evaluate_cond_node() Documentation,selinux: deprecate setting checkreqprot to 1 selinux: move status variables out of selinux_ss
2020-03-31Merge branch 'x86-vmware-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 vmware updates from Ingo Molnar: "The main change in this tree is the addition of 'steal time clock support' for VMware guests" * 'x86-vmware-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/vmware: Use bool type for vmw_sched_clock x86/vmware: Enable steal time accounting x86/vmware: Add steal time clock support for VMware guests x86/vmware: Remove vmware_sched_clock_setup() x86/vmware: Make vmware_select_hypercall() __init
2020-03-31Merge tag 'kvmarm-5.7' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm updates for Linux 5.7 - GICv4.1 support - 32bit host removal
2020-03-30Merge tag 'x86-splitlock-2020-03-30' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 splitlock updates from Thomas Gleixner: "Support for 'split lock' detection: Atomic operations (lock prefixed instructions) which span two cache lines have to acquire the global bus lock. This is at least 1k cycles slower than an atomic operation within a cache line and disrupts performance on other cores. Aside of performance disruption this is a unpriviledged form of DoS. Some newer CPUs have the capability to raise an #AC trap when such an operation is attempted. The detection is by default enabled in warning mode which will warn once when a user space application is caught. A command line option allows to disable the detection or to select fatal mode which will terminate offending applications with SIGBUS" * tag 'x86-splitlock-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/split_lock: Avoid runtime reads of the TEST_CTRL MSR x86/split_lock: Rework the initialization flow of split lock detection x86/split_lock: Enable split lock detection by kernel
2020-03-30Merge 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 are: - Various NUMA scheduling updates: harmonize the load-balancer and NUMA placement logic to not work against each other. The intended result is better locality, better utilization and fewer migrations. - Introduce Thermal Pressure tracking and optimizations, to improve task placement on thermally overloaded systems. - Implement frequency invariant scheduler accounting on (some) x86 CPUs. This is done by observing and sampling the 'recent' CPU frequency average at ~tick boundaries. The CPU provides this data via the APERF/MPERF MSRs. This hopefully makes our capacity estimates more precise and keeps tasks on the same CPU better even if it might seem overloaded at a lower momentary frequency. (As usual, turbo mode is a complication that we resolve by observing the maximum frequency and renormalizing to it.) - Add asymmetric CPU capacity wakeup scan to improve capacity utilization on asymmetric topologies. (big.LITTLE systems) - PSI fixes and optimizations. - RT scheduling capacity awareness fixes & improvements. - Optimize the CONFIG_RT_GROUP_SCHED constraints code. - Misc fixes, cleanups and optimizations - see the changelog for details" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (62 commits) threads: Update PID limit comment according to futex UAPI change sched/fair: Fix condition of avg_load calculation sched/rt: cpupri_find: Trigger a full search as fallback kthread: Do not preempt current task if it is going to call schedule() sched/fair: Improve spreading of utilization sched: Avoid scale real weight down to zero psi: Move PF_MEMSTALL out of task->flags MAINTAINERS: Add maintenance information for psi psi: Optimize switching tasks inside shared cgroups psi: Fix cpu.pressure for cpu.max and competing cgroups sched/core: Distribute tasks within affinity masks sched/fair: Fix enqueue_task_fair warning thermal/cpu-cooling, sched/core: Move the arch_set_thermal_pressure() API to generic scheduler code sched/rt: Remove unnecessary push for unfit tasks sched/rt: Allow pulling unfitting task sched/rt: Optimize cpupri_find() on non-heterogenous systems sched/rt: Re-instate old behavior in select_task_rq_rt() sched/rt: cpupri_find: Implement fallback mechanism for !fit case sched/fair: Fix reordering of enqueue/dequeue_task_fair() sched/fair: Fix runnable_avg for throttled cfs ...
2020-03-30Merge branch 'core-rcu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU updates from Ingo Molnar: "The main changes in this cycle were: - Make kfree_rcu() use kfree_bulk() for added performance - RCU updates - Callback-overload handling updates - Tasks-RCU KCSAN and sparse updates - Locking torture test and RCU torture test updates - Documentation updates - Miscellaneous fixes" * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (74 commits) rcu: Make rcu_barrier() account for offline no-CBs CPUs rcu: Mark rcu_state.gp_seq to detect concurrent writes Documentation/memory-barriers: Fix typos doc: Add rcutorture scripting to torture.txt doc/RCU/rcu: Use https instead of http if possible doc/RCU/rcu: Use absolute paths for non-rst files doc/RCU/rcu: Use ':ref:' for links to other docs doc/RCU/listRCU: Update example function name doc/RCU/listRCU: Fix typos in a example code snippets doc/RCU/Design: Remove remaining HTML tags in ReST files doc: Add some more RCU list patterns in the kernel rcutorture: Set KCSAN Kconfig options to detect more data races rcutorture: Manually clean up after rcu_barrier() failure rcutorture: Make rcu_torture_barrier_cbs() post from corresponding CPU rcuperf: Measure memory footprint during kfree_rcu() test rcutorture: Annotation lockless accesses to rcu_torture_current rcutorture: Add READ_ONCE() to rcu_torture_count and rcu_torture_batch rcutorture: Fix stray access to rcu_fwd_cb_nodelay rcutorture: Fix rcu_torture_one_read()/rcu_torture_writer() data race rcutorture: Make kvm-find-errors.sh abort on bad directory ...
2020-03-30Merge tag 'acpi-5.7-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI updates from Rafael Wysocki: - Update the ACPICA code in the kernel to the 20200214 upstream release including: * Fix to re-enable the sleep button after wakeup (Anchal Agarwal). * Fixes for mistakes in comments and typos (Bob Moore). * ASL-ASL+ converter updates (Erik Kaneda). * Type casting cleanups (Sven Barth). - Clean up the intialization of the EC driver and eliminate some dead code from it (Rafael Wysocki). - Clean up the quirk tables in the AC and battery drivers (Hans de Goede). - Fix the global lock handling on x86 to ignore unspecified bit positions in the global lock field (Jan Engelhardt). - Add a new "tiny" driver for ACPI button devices exposed by VMs to guest kernels to send signals directly to init (Josh Triplett). - Add a kernel parameter to disable ACPI BGRT on x86 (Alex Hung). - Make the ACPI PCI host bridge and fan drivers use scnprintf() to avoid potential buffer overflows (Takashi Iwai). - Clean up assorted pieces of code: * Reorder "asmlinkage" to make g++ happy (Alexey Dobriyan). * Drop unneeded variable initialization (Colin Ian King). * Add missing __acquires/__releases annotations (Jules Irenge). * Replace list_for_each_safe() with list_for_each_entry_safe() (chenqiwu)" * tag 'acpi-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (31 commits) ACPICA: Update version to 20200214 ACPI: PCI: Use scnprintf() for avoiding potential buffer overflow ACPI: fan: Use scnprintf() for avoiding potential buffer overflow ACPI: EC: Eliminate EC_FLAGS_QUERY_HANDSHAKE ACPI: EC: Do not clear boot_ec_is_ecdt in acpi_ec_add() ACPI: EC: Simplify acpi_ec_ecdt_start() and acpi_ec_init() ACPI: EC: Consolidate event handler installation code acpi/x86: ignore unspecified bit positions in the ACPI global lock field acpi/x86: add a kernel parameter to disable ACPI BGRT x86/acpi: make "asmlinkage" part first thing in the function definition ACPI: list_for_each_safe() -> list_for_each_entry_safe() ACPI: video: remove redundant assignments to variable result ACPI: OSL: Add missing __acquires/__releases annotations ACPI / battery: Cleanup Lenovo Ideapad Miix 320 DMI table entry ACPI / AC: Cleanup DMI quirk table ACPI: EC: Use fast path in acpi_ec_add() for DSDT boot EC ACPI: EC: Simplify acpi_ec_add() ACPI: EC: Drop AE_NOT_FOUND special case from ec_install_handlers() ACPI: EC: Avoid passing redundant argument to functions ACPI: EC: Avoid printing confusing messages in acpi_ec_setup() ...
2020-03-30Merge tag 'pm-5.7-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "These clean up and rework the PM QoS API, address a suspend-to-idle wakeup regression on some ACPI-based platforms, clean up and extend a few cpuidle drivers, update multiple cpufreq drivers and cpufreq documentation, and fix a number of issues in devfreq and several other things all over. Specifics: - Clean up and rework the PM QoS API to simplify the code and reduce the size of it (Rafael Wysocki). - Fix a suspend-to-idle wakeup regression on Dell XPS13 9370 and similar platforms where the USB plug/unplug events are handled by the EC (Rafael Wysocki). - CLean up the intel_idle and PSCI cpuidle drivers (Rafael Wysocki, Ulf Hansson). - Extend the haltpoll cpuidle driver so that it can be forced to run on some systems where it refused to load (Maciej Szmigiero). - Convert several cpufreq documents to the .rst format and move the legacy driver documentation into one common file (Mauro Carvalho Chehab, Rafael Wysocki). - Update several cpufreq drivers: * Extend and fix the imx-cpufreq-dt driver (Anson Huang). * Improve the -EPROBE_DEFER handling and fix unwanted CPU overclocking on i.MX6ULL in imx6q-cpufreq (Anson Huang, Christoph Niedermaier). * Add support for Krait based SoCs to the qcom driver (Ansuel Smith). * Add support for OPP_PLUS to ti-cpufreq (Lokesh Vutla). * Add platform specific intermediate callbacks support to cpufreq-dt and update the imx6q driver (Peng Fan). * Simplify and consolidate some pieces of the intel_pstate driver and update its documentation (Rafael Wysocki, Alex Hung). - Fix several devfreq issues: * Remove unneeded extern keyword from a devfreq header file and use the DEVFREQ_GOV_UPDATE_INTERNAL event name instead of DEVFREQ_GOV_INTERNAL (Chanwoo Choi). * Fix the handling of dev_pm_qos_remove_request() result (Leonard Crestez). * Use constant name for userspace governor (Pierre Kuo). * Get rid of doc warnings and fix a typo (Christophe JAILLET). - Use built-in RCU list checking in some places in the PM core to avoid false-positive RCU usage warnings (Madhuparna Bhowmik). - Add explicit READ_ONCE()/WRITE_ONCE() annotations to low-level PM QoS routines (Qian Cai). - Fix removal of wakeup sources to avoid NULL pointer dereferences in a corner case (Neeraj Upadhyay). - Clean up the handling of hibernate compat ioctls and fix the related documentation (Eric Biggers). - Update the idle_inject power capping driver to use variable-length arrays instead of zero-length arrays (Gustavo Silva). - Fix list format in a PM QoS document (Randy Dunlap). - Make the cpufreq stats module use scnprintf() to avoid potential buffer overflows (Takashi Iwai). - Add pm_runtime_get_if_active() to PM-runtime API (Sakari Ailus). - Allow no domain-idle-states DT property in generic PM domains (Ulf Hansson). - Fix a broken y-axis scale in the intel_pstate_tracer utility (Doug Smythies)" * tag 'pm-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (78 commits) cpufreq: intel_pstate: Simplify intel_pstate_cpu_init() tools/power/x86/intel_pstate_tracer: fix a broken y-axis scale ACPI: PM: s2idle: Refine active GPEs check ACPICA: Allow acpi_any_gpe_status_set() to skip one GPE PM: sleep: wakeup: Skip wakeup_source_sysfs_remove() if device is not there PM / devfreq: Get rid of some doc warnings PM / devfreq: Fix handling dev_pm_qos_remove_request result PM / devfreq: Fix a typo in a comment PM / devfreq: Change to DEVFREQ_GOV_UPDATE_INTERVAL event name PM / devfreq: Remove unneeded extern keyword PM / devfreq: Use constant name of userspace governor ACPI: PM: s2idle: Fix comment in acpi_s2idle_prepare_late() cpufreq: qcom: Add support for krait based socs cpufreq: imx6q-cpufreq: Improve the logic of -EPROBE_DEFER handling cpufreq: Use scnprintf() for avoiding potential buffer overflow cpuidle: psci: Split psci_dt_cpu_init_idle() PM / Domains: Allow no domain-idle-states DT property in genpd when parsing PM / hibernate: Remove unnecessary compat ioctl overrides PM: hibernate: fix docs for ioctls that return loff_t via pointer Documentation: intel_pstate: update links for references ...
2020-03-30Merge tag 'driver-core-5.7-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the "big" set of driver core changes for 5.7-rc1. Nothing huge in here, just lots of little firmware core changes and use of new apis, a libfs fix, a debugfs api change, and some driver core deferred probe rework. All of these have been in linux-next for a while with no reported issues" * tag 'driver-core-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (44 commits) Revert "driver core: Set fw_devlink to "permissive" behavior by default" driver core: Set fw_devlink to "permissive" behavior by default driver core: Replace open-coded list_last_entry() driver core: Read atomic counter once in driver_probe_done() libfs: fix infoleak in simple_attr_read() driver core: Add device links from fwnode only for the primary device platform/x86: touchscreen_dmi: Add info for the Chuwi Vi8 Plus tablet platform/x86: touchscreen_dmi: Add EFI embedded firmware info support Input: icn8505 - Switch to firmware_request_platform for retreiving the fw Input: silead - Switch to firmware_request_platform for retreiving the fw selftests: firmware: Add firmware_request_platform tests test_firmware: add support for firmware_request_platform firmware: Add new platform fallback mechanism and firmware_request_platform() Revert "drivers: base: power: wakeup.c: Use built-in RCU list checking" drivers: base: power: wakeup.c: Use built-in RCU list checking component: allow missing unbind callback debugfs: remove return value of debugfs_create_file_size() debugfs: Check module state before warning in {full/open}_proxy_open() firmware: fix a double abort case with fw_load_sysfs_fallback arch_topology: Fix putting invalid cpu clk ...
2020-03-30Merge tag 'docs-5.7' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "This has been a busy cycle for documentation work. Highlights include: - Lots of RST conversion work by Mauro, Daniel ALmeida, and others. Maybe someday we'll get to the end of this stuff...maybe... - Some organizational work to bring some order to the core-api manual. - Various new docs and additions to the existing documentation. - Typo fixes, warning fixes, ..." * tag 'docs-5.7' of git://git.lwn.net/linux: (123 commits) Documentation: x86: exception-tables: document CONFIG_BUILDTIME_TABLE_SORT MAINTAINERS: adjust to filesystem doc ReST conversion docs: deprecated.rst: Add BUG()-family doc: zh_CN: add translation for virtiofs doc: zh_CN: index files in filesystems subdirectory docs: locking: Drop :c:func: throughout docs: locking: Add 'need' to hardirq section docs: conf.py: avoid thousands of duplicate label warning on Sphinx docs: prevent warnings due to autosectionlabel docs: fix reference to core-api/namespaces.rst docs: fix pointers to io-mapping.rst and io_ordering.rst files Documentation: Better document the softlockup_panic sysctl docs: hw-vuln: tsx_async_abort.rst: get rid of an unused ref docs: perf: imx-ddr.rst: get rid of a warning docs: filesystems: fuse.rst: supress a Sphinx warning docs: translations: it: avoid duplicate refs at programming-language.rst docs: driver.rst: supress two ReSt warnings docs: trace: events.rst: convert some new stuff to ReST format Documentation: Add io_ordering.rst to driver-api manual Documentation: Add io-mapping.rst to driver-api manual ...
2020-03-30Merge branches 'pm-devfreq', 'powercap' and 'pm-docs'Rafael J. Wysocki
* pm-devfreq: PM / devfreq: Get rid of some doc warnings PM / devfreq: Fix handling dev_pm_qos_remove_request result PM / devfreq: Fix a typo in a comment PM / devfreq: Change to DEVFREQ_GOV_UPDATE_INTERVAL event name PM / devfreq: Remove unneeded extern keyword PM / devfreq: Use constant name of userspace governor * powercap: powercap: idle_inject: Replace zero-length array with flexible-array member * pm-docs: docs: cpu-freq: convert cpufreq-stats.txt to ReST docs: cpu-freq: convert cpu-drivers.txt to ReST docs: cpu-freq: convert core.txt to ReST docs: cpu-freq: convert index.txt to ReST docs: cpufreq: fix a broken reference Documentation: cpufreq: Move legacy driver documentation
2020-03-30Merge branch 'pm-cpufreq'Rafael J. Wysocki
* pm-cpufreq: cpufreq: intel_pstate: Simplify intel_pstate_cpu_init() cpufreq: qcom: Add support for krait based socs cpufreq: imx6q-cpufreq: Improve the logic of -EPROBE_DEFER handling cpufreq: Use scnprintf() for avoiding potential buffer overflow Documentation: intel_pstate: update links for references cpufreq: intel_pstate: Consolidate policy verification cpufreq: dt: Allow platform specific intermediate callbacks cpufreq: imx-cpufreq-dt: Correct i.MX8MP's market segment fuse location cpufreq: imx6q: read OCOTP through nvmem for imx6q cpufreq: imx6q: fix error handling cpufreq: imx-cpufreq-dt: Add "cpu-supply" property check cpufreq: ti-cpufreq: Add support for OPP_PLUS cpufreq: imx6q: Fixes unwanted cpu overclocking on i.MX6ULL
2020-03-30Merge branch 'pm-qos'Rafael J. Wysocki
* pm-qos: (30 commits) PM: QoS: annotate data races in pm_qos_*_value() Documentation: power: fix pm_qos_interface.rst format warning PM: QoS: Make CPU latency QoS depend on CONFIG_CPU_IDLE Documentation: PM: QoS: Update to reflect previous code changes PM: QoS: Update file information comments PM: QoS: Drop PM_QOS_CPU_DMA_LATENCY and rename related functions sound: Call cpu_latency_qos_*() instead of pm_qos_*() drivers: usb: Call cpu_latency_qos_*() instead of pm_qos_*() drivers: tty: Call cpu_latency_qos_*() instead of pm_qos_*() drivers: spi: Call cpu_latency_qos_*() instead of pm_qos_*() drivers: net: Call cpu_latency_qos_*() instead of pm_qos_*() drivers: mmc: Call cpu_latency_qos_*() instead of pm_qos_*() drivers: media: Call cpu_latency_qos_*() instead of pm_qos_*() drivers: hsi: Call cpu_latency_qos_*() instead of pm_qos_*() drm: i915: Call cpu_latency_qos_*() instead of pm_qos_*() x86: platform: iosf_mbi: Call cpu_latency_qos_*() instead of pm_qos_*() cpuidle: Call cpu_latency_qos_limit() instead of pm_qos_request() PM: QoS: Add CPU latency QoS API wrappers PM: QoS: Adjust pm_qos_request() signature and reorder pm_qos.h PM: QoS: Simplify definitions of CPU latency QoS trace events ...
2020-03-25block/diskstats: more accurate approximation of io_ticks for slow disksKonstantin Khlebnikov
Currently io_ticks is approximated by adding one at each start and end of requests if jiffies counter has changed. This works perfectly for requests shorter than a jiffy or if one of requests starts/ends at each jiffy. If disk executes just one request at a time and they are longer than two jiffies then only first and last jiffies will be accounted. Fix is simple: at the end of request add up into io_ticks jiffies passed since last update rather than just one jiffy. Example: common HDD executes random read 4k requests around 12ms. fio --name=test --filename=/dev/sdb --rw=randread --direct=1 --runtime=30 & iostat -x 10 sdb Note changes of iostat's "%util" 8,43% -> 99,99% before/after patch: Before: Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await r_await w_await svctm %util sdb 0,00 0,00 82,60 0,00 330,40 0,00 8,00 0,96 12,09 12,09 0,00 1,02 8,43 After: Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await r_await w_await svctm %util sdb 0,00 0,00 82,50 0,00 330,00 0,00 8,00 1,00 12,10 12,10 0,00 12,12 99,99 Now io_ticks does not loose time between start and end of requests, but for queue-depth > 1 some I/O time between adjacent starts might be lost. For load estimation "%util" is not as useful as average queue length, but it clearly shows how often disk queue is completely empty. Fixes: 5b18b5a73760 ("block: delete part_round_stats and switch to less precise counting") Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-24Merge branch 'for-mingo' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu Pull RCU changes from Paul E. McKenney: - Make kfree_rcu() use kfree_bulk() for added performance - RCU updates - Callback-overload handling updates - Tasks-RCU KCSAN and sparse updates - Locking torture test and RCU torture test updates - Documentation updates - Miscellaneous fixes Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-03-24x86/vmware: Enable steal time accountingAlexey Makhalov
Set paravirt_steal_rq_enabled if steal clock present. paravirt_steal_rq_enabled is used in sched/core.c to adjust task progress by offsetting stolen time. Use 'no-steal-acc' off switch (share same name with KVM) to disable steal time accounting. Signed-off-by: Alexey Makhalov <amakhalov@vmware.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200323195707.31242-5-amakhalov@vmware.com
2020-03-21Merge branches 'doc.2020.02.27a', 'fixes.2020.03.21a', ↵Paul E. McKenney
'kfree_rcu.2020.02.20a', 'locktorture.2020.02.20a', 'ovld.2020.02.20a', 'rcu-tasks.2020.02.20a', 'srcu.2020.02.20a' and 'torture.2020.02.20a' into HEAD doc.2020.02.27a: Documentation updates. fixes.2020.03.21a: Miscellaneous fixes. kfree_rcu.2020.02.20a: Updates to kfree_rcu(). locktorture.2020.02.20a: Lock torture-test updates. ovld.2020.02.20a: Updates to callback-overload handling. rcu-tasks.2020.02.20a: RCU-tasks updates. srcu.2020.02.20a: SRCU updates. torture.2020.02.20a: Torture-test updates.
2020-03-17docs: Add reference in binfmt-misc.rstRomuald Brunet
While looking at the binfmt-misc documentation I noticed that there is a reference to the “java” example that could be a direct link. This patch simply adds the link without changing the HTML output. Signed-off-by: Romuald Brunet <romuald@chivil.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2020-03-14Documentation: intel_pstate: update links for referencesAlex Hung
URLs for presentation and Intel Software Developer’s Manual are updated as they were using "http" which are gradually replaced by "https". Signed-off-by: Alex Hung <alex.hung@canonical.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-14acpi/x86: add a kernel parameter to disable ACPI BGRTAlex Hung
BGRT is for displaying seamless OEM logo from booting to login screen; however, this mechanism does not always work well on all configurations and the OEM logo can be displayed multiple times. This looks worse than without BGRT enabled. This patch adds a kernel parameter to disable BGRT in boot time. This is easier than re-compiling a kernel with CONFIG_ACPI_BGRT disabled. Signed-off-by: Alex Hung <alex.hung@canonical.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller
Daniel Borkmann says: ==================== pull-request: bpf-next 2020-03-13 The following pull-request contains BPF updates for your *net-next* tree. We've added 86 non-merge commits during the last 12 day(s) which contain a total of 107 files changed, 5771 insertions(+), 1700 deletions(-). The main changes are: 1) Add modify_return attach type which allows to attach to a function via BPF trampoline and is run after the fentry and before the fexit programs and can pass a return code to the original caller, from KP Singh. 2) Generalize BPF's kallsyms handling and add BPF trampoline and dispatcher objects to be visible in /proc/kallsyms so they can be annotated in stack traces, from Jiri Olsa. 3) Extend BPF sockmap to allow for UDP next to existing TCP support in order in order to enable this for BPF based socket dispatch, from Lorenz Bauer. 4) Introduce a new bpftool 'prog profile' command which attaches to existing BPF programs via fentry and fexit hooks and reads out hardware counters during that period, from Song Liu. Example usage: bpftool prog profile id 337 duration 3 cycles instructions llc_misses 4228 run_cnt 3403698 cycles (84.08%) 3525294 instructions # 1.04 insn per cycle (84.05%) 13 llc_misses # 3.69 LLC misses per million isns (83.50%) 5) Batch of improvements to libbpf, bpftool and BPF selftests. Also addition of a new bpf_link abstraction to keep in particular BPF tracing programs attached even when the applicaion owning them exits, from Andrii Nakryiko. 6) New bpf_get_current_pid_tgid() helper for tracing to perform PID filtering and which returns the PID as seen by the init namespace, from Carlos Neira. 7) Refactor of RISC-V JIT code to move out common pieces and addition of a new RV32G BPF JIT compiler, from Luke Nelson. 8) Add gso_size context member to __sk_buff in order to be able to know whether a given skb is GSO or not, from Willem de Bruijn. 9) Add a new bpf_xdp_output() helper which reuses XDP's existing perf RB output implementation but can be called from tracepoint programs, from Eelco Chaudron. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>