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2018-11-03Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "A number of fixes and some late updates: - make in_compat_syscall() behavior on x86-32 similar to other platforms, this touches a number of generic files but is not intended to impact non-x86 platforms. - objtool fixes - PAT preemption fix - paravirt fixes/cleanups - cpufeatures updates for new instructions - earlyprintk quirk - make microcode version in sysfs world-readable (it is already world-readable in procfs) - minor cleanups and fixes" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: compat: Cleanup in_compat_syscall() callers x86/compat: Adjust in_compat_syscall() to generic code under !COMPAT objtool: Support GCC 9 cold subfunction naming scheme x86/numa_emulation: Fix uniform-split numa emulation x86/paravirt: Remove unused _paravirt_ident_32 x86/mm/pat: Disable preemption around __flush_tlb_all() x86/paravirt: Remove GPL from pv_ops export x86/traps: Use format string with panic() call x86: Clean up 'sizeof x' => 'sizeof(x)' x86/cpufeatures: Enumerate MOVDIR64B instruction x86/cpufeatures: Enumerate MOVDIRI instruction x86/earlyprintk: Add a force option for pciserial device objtool: Support per-function rodata sections x86/microcode: Make revision and processor flags world-readable
2018-11-03Merge branch 'core/urgent' into x86/urgent, to pick up objtool fixIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-11-02Merge tag 'for-linus-20181102' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block layer fixes from Jens Axboe: "The biggest part of this pull request is the revert of the blkcg cleanup series. It had one fix earlier for a stacked device issue, but another one was reported. Rather than play whack-a-mole with this, revert the entire series and try again for the next kernel release. Apart from that, only small fixes/changes. Summary: - Indentation fixup for mtip32xx (Colin Ian King) - The blkcg cleanup series revert (Dennis Zhou) - Two NVMe fixes. One fixing a regression in the nvme request initialization in this merge window, causing nvme-fc to not work. The other is a suspend/resume p2p resource issue (James, Keith) - Fix sg discard merge, allowing us to merge in cases where we didn't before (Jianchao Wang) - Call rq_qos_exit() after the queue is frozen, preventing a hang (Ming) - Fix brd queue setup, fixing an oops if we fail setting up all devices (Ming)" * tag 'for-linus-20181102' of git://git.kernel.dk/linux-block: nvme-pci: fix conflicting p2p resource adds nvme-fc: fix request private initialization blkcg: revert blkcg cleanups series block: brd: associate with queue until adding disk block: call rq_qos_exit() after queue is frozen mtip32xx: clean an indentation issue, remove extraneous tabs block: fix the DISCARD request merge
2018-11-01blkcg: revert blkcg cleanups seriesDennis Zhou
This reverts a series committed earlier due to null pointer exception bug report in [1]. It seems there are edge case interactions that I did not consider and will need some time to understand what causes the adverse interactions. The original series can be found in [2] with a follow up series in [3]. [1] https://www.spinics.net/lists/cgroups/msg20719.html [2] https://lore.kernel.org/lkml/20180911184137.35897-1-dennisszhou@gmail.com/ [3] https://lore.kernel.org/lkml/20181020185612.51587-1-dennis@kernel.org/ This reverts the following commits: d459d853c2ed, b2c3fa546705, 101246ec02b5, b3b9f24f5fcc, e2b0989954ae, f0fcb3ec89f3, c839e7a03f92, bdc2491708c4, 74b7c02a9bc1, 5bf9a1f3b4ef, a7b39b4e961c, 07b05bcc3213, 49f4c2dc2b50, 27e6fa996c53 Signed-off-by: Dennis Zhou <dennis@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-10-31memory-hotplug.rst: add some details about locking internalsDavid Hildenbrand
Let's document the magic a bit, especially why device_hotplug_lock is required when adding/removing memory and how it all play together with requests to online/offline memory from user space. Link: http://lkml.kernel.org/r/20180925091457.28651-7-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Pavel Tatashin <pavel.tatashin@microsoft.com> Reviewed-by: Rashmica Gupta <rashmica.g@gmail.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: John Allen <jallen@linux.vnet.ibm.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Len Brown <lenb@kernel.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Mathieu Malaterre <malat@debian.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michael Neuling <mikey@neuling.org> Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: YASUAKI ISHIMATSU <yasu.isimatu@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-29Merge branches 'x86/early-printk', 'x86/microcode' and 'core/objtool' into ↵Ingo Molnar
x86/urgent, to pick up simple topic branches Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-26Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge updates from Andrew Morton: - a few misc things - ocfs2 updates - most of MM * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (132 commits) hugetlbfs: dirty pages as they are added to pagecache mm: export add_swap_extent() mm: split SWP_FILE into SWP_ACTIVATED and SWP_FS tools/testing/selftests/vm/map_fixed_noreplace.c: add test for MAP_FIXED_NOREPLACE mm: thp: relocate flush_cache_range() in migrate_misplaced_transhuge_page() mm: thp: fix mmu_notifier in migrate_misplaced_transhuge_page() mm: thp: fix MADV_DONTNEED vs migrate_misplaced_transhuge_page race condition mm/kasan/quarantine.c: make quarantine_lock a raw_spinlock_t mm/gup: cache dev_pagemap while pinning pages Revert "x86/e820: put !E820_TYPE_RAM regions into memblock.reserved" mm: return zero_resv_unavail optimization mm: zero remaining unavailable struct pages tools/testing/selftests/vm/gup_benchmark.c: add MAP_HUGETLB option tools/testing/selftests/vm/gup_benchmark.c: add MAP_SHARED option tools/testing/selftests/vm/gup_benchmark.c: allow user specified file tools/testing/selftests/vm/gup_benchmark.c: fix 'write' flag usage mm/gup_benchmark.c: add additional pinning methods mm/gup_benchmark.c: time put_page() mm: don't raise MEMCG_OOM event due to failed high-order allocation mm/page-writeback.c: fix range_cyclic writeback vs writepages deadlock ...
2018-10-26mm: don't raise MEMCG_OOM event due to failed high-order allocationRoman Gushchin
It was reported that on some of our machines containers were restarted with OOM symptoms without an obvious reason. Despite there were almost no memory pressure and plenty of page cache, MEMCG_OOM event was raised occasionally, causing the container management software to think, that OOM has happened. However, no tasks have been killed. The following investigation showed that the problem is caused by a failing attempt to charge a high-order page. In such case, the OOM killer is never invoked. As shown below, it can happen under conditions, which are very far from a real OOM: e.g. there is plenty of clean page cache and no memory pressure. There is no sense in raising an OOM event in this case, as it might confuse a user and lead to wrong and excessive actions (e.g. restart the workload, as in my case). Let's look at the charging path in try_charge(). If the memory usage is about memory.max, which is absolutely natural for most memory cgroups, we try to reclaim some pages. Even if we were able to reclaim enough memory for the allocation, the following check can fail due to a race with another concurrent allocation: if (mem_cgroup_margin(mem_over_limit) >= nr_pages) goto retry; For regular pages the following condition will save us from triggering the OOM: if (nr_reclaimed && nr_pages <= (1 << PAGE_ALLOC_COSTLY_ORDER)) goto retry; But for high-order allocation this condition will intentionally fail. The reason behind is that we'll likely fall to regular pages anyway, so it's ok and even preferred to return ENOMEM. In this case the idea of raising MEMCG_OOM looks dubious. Fix this by moving MEMCG_OOM raising to mem_cgroup_oom() after allocation order check, so that the event won't be raised for high order allocations. This change doesn't affect regular pages allocation and charging. Link: http://lkml.kernel.org/r/20181004214050.7417-1-guro@fb.com Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Michal Hocko <mhocko@kernel.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-26mm: provide kernel parameter to allow disabling page init poisoningAlexander Duyck
Patch series "Address issues slowing persistent memory initialization", v5. The main thing this patch set achieves is that it allows us to initialize each node worth of persistent memory independently. As a result we reduce page init time by about 2 minutes because instead of taking 30 to 40 seconds per node and going through each node one at a time, we process all 4 nodes in parallel in the case of a 12TB persistent memory setup spread evenly over 4 nodes. This patch (of 3): On systems with a large amount of memory it can take a significant amount of time to initialize all of the page structs with the PAGE_POISON_PATTERN value. I have seen it take over 2 minutes to initialize a system with over 12TB of RAM. In order to work around the issue I had to disable CONFIG_DEBUG_VM and then the boot time returned to something much more reasonable as the arch_add_memory call completed in milliseconds versus seconds. However in doing that I had to disable all of the other VM debugging on the system. In order to work around a kernel that might have CONFIG_DEBUG_VM enabled on a system that has a large amount of memory I have added a new kernel parameter named "vm_debug" that can be set to "-" in order to disable it. Link: http://lkml.kernel.org/r/20180925201921.3576.84239.stgit@localhost.localdomain Reviewed-by: Pavel Tatashin <pavel.tatashin@microsoft.com> Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-26psi: cgroup supportJohannes Weiner
On a system that executes multiple cgrouped jobs and independent workloads, we don't just care about the health of the overall system, but also that of individual jobs, so that we can ensure individual job health, fairness between jobs, or prioritize some jobs over others. This patch implements pressure stall tracking for cgroups. In kernels with CONFIG_PSI=y, cgroup2 groups will have cpu.pressure, memory.pressure, and io.pressure files that track aggregate pressure stall times for only the tasks inside the cgroup. Link: http://lkml.kernel.org/r/20180828172258.3185-10-hannes@cmpxchg.org Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Daniel Drake <drake@endlessm.com> Tested-by: Suren Baghdasaryan <surenb@google.com> Cc: Christopher Lameter <cl@linux.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Johannes Weiner <jweiner@fb.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Enderborg <peter.enderborg@sony.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Shakeel Butt <shakeelb@google.com> Cc: Vinayak Menon <vinmenon@codeaurora.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-26Merge tag 'powerpc-4.20-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Notable changes: - A large series to rewrite our SLB miss handling, replacing a lot of fairly complicated asm with much fewer lines of C. - Following on from that, we now maintain a cache of SLB entries for each process and preload them on context switch. Leading to a 27% speedup for our context switch benchmark on Power9. - Improvements to our handling of SLB multi-hit errors. We now print more debug information when they occur, and try to continue running by flushing the SLB and reloading, rather than treating them as fatal. - Enable THP migration on 64-bit Book3S machines (eg. Power7/8/9). - Add support for physical memory up to 2PB in the linear mapping on 64-bit Book3S. We only support up to 512TB as regular system memory, otherwise the percpu allocator runs out of vmalloc space. - Add stack protector support for 32 and 64-bit, with a per-task canary. - Add support for PTRACE_SYSEMU and PTRACE_SYSEMU_SINGLESTEP. - Support recognising "big cores" on Power9, where two SMT4 cores are presented to us as a single SMT8 core. - A large series to cleanup some of our ioremap handling and PTE flags. - Add a driver for the PAPR SCM (storage class memory) interface, allowing guests to operate on SCM devices (acked by Dan). - Changes to our ftrace code to handle very large kernels, where we need to use a trampoline to get to ftrace_caller(). And many other smaller enhancements and cleanups. Thanks to: Alan Modra, Alistair Popple, Aneesh Kumar K.V, Anton Blanchard, Aravinda Prasad, Bartlomiej Zolnierkiewicz, Benjamin Herrenschmidt, Breno Leitao, Cédric Le Goater, Christophe Leroy, Christophe Lombard, Dan Carpenter, Daniel Axtens, Finn Thain, Gautham R. Shenoy, Gustavo Romero, Haren Myneni, Hari Bathini, Jia Hongtao, Joel Stanley, John Allen, Laurent Dufour, Madhavan Srinivasan, Mahesh Salgaonkar, Mark Hairgrove, Masahiro Yamada, Michael Bringmann, Michael Neuling, Michal Suchanek, Murilo Opsfelder Araujo, Nathan Fontenot, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers, Oliver O'Halloran, Paul Mackerras, Petr Vorel, Rashmica Gupta, Reza Arbab, Rob Herring, Sam Bobroff, Samuel Mendoza-Jonas, Scott Wood, Stan Johnson, Stephen Rothwell, Stewart Smith, Suraj Jitindar Singh, Tyrel Datwyler, Vaibhav Jain, Vasant Hegde, YueHaibing, zhong jiang" * tag 'powerpc-4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (221 commits) Revert "selftests/powerpc: Fix out-of-tree build errors" powerpc/msi: Fix compile error on mpc83xx powerpc: Fix stack protector crashes on CPU hotplug powerpc/traps: restore recoverability of machine_check interrupts powerpc/64/module: REL32 relocation range check powerpc/64s/radix: Fix radix__flush_tlb_collapsed_pmd double flushing pmd selftests/powerpc: Add a test of wild bctr powerpc/mm: Fix page table dump to work on Radix powerpc/mm/radix: Display if mappings are exec or not powerpc/mm/radix: Simplify split mapping logic powerpc/mm/radix: Remove the retry in the split mapping logic powerpc/mm/radix: Fix small page at boundary when splitting powerpc/mm/radix: Fix overuse of small pages in splitting logic powerpc/mm/radix: Fix off-by-one in split mapping logic powerpc/ftrace: Handle large kernel configs powerpc/mm: Fix WARN_ON with THP NUMA migration selftests/powerpc: Fix out-of-tree build errors powerpc/time: no steal_time when CONFIG_PPC_SPLPAR is not selected powerpc/time: Only set CONFIG_ARCH_HAS_SCALED_CPUTIME on PPC64 powerpc/time: isolate scaled cputime accounting in dedicated functions. ...
2018-10-26Merge tag 'iommu-updates-v4.20' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu Pull IOMMU updates from Joerg Roedel: - Debugfs support for the Intel VT-d driver. When enabled, it now also exposes some of its internal data structures to user-space for debugging purposes. - ARM-SMMU driver now uses the generic deferred flushing and fast-path iova allocation code. This is expected to be a major performance improvement, as this allocation path scales a lot better. - Support for r8a7744 in the Renesas iommu driver - Couple of minor fixes and improvements all over the place * tag 'iommu-updates-v4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (39 commits) iommu/arm-smmu-v3: Remove unnecessary wrapper function iommu/arm-smmu-v3: Add SPDX header iommu/amd: Add default branch in amd_iommu_capable() dt-bindings: iommu: ipmmu-vmsa: Add r8a7744 support iommu/amd: Move iommu_init_pci() to .init section iommu/arm-smmu: Support non-strict mode iommu/io-pgtable-arm-v7s: Add support for non-strict mode iommu/arm-smmu-v3: Add support for non-strict mode iommu/io-pgtable-arm: Add support for non-strict mode iommu: Add "iommu.strict" command line option iommu/dma: Add support for non-strict mode iommu/arm-smmu: Ensure that page-table updates are visible before TLBI iommu/arm-smmu-v3: Implement flush_iotlb_all hook iommu/arm-smmu-v3: Avoid back-to-back CMD_SYNC operations iommu/arm-smmu-v3: Fix unexpected CMD_SYNC timeout iommu/io-pgtable-arm: Fix race handling in split_blk_unmap() iommu/arm-smmu-v3: Fix a couple of minor comment typos iommu: Fix a typo iommu: Remove .domain_{get,set}_windows iommu: Tidy up window attributes ...
2018-10-26Merge tag 'char-misc-4.20-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 patches for 4.20-rc1. Loads of things here, we have new code in all of these driver subsystems: - fpga - stm - extcon - nvmem - eeprom - hyper-v - gsmi - coresight - thunderbolt - vmw_balloon - goldfish - soundwire along with lots of fixes and minor changes to other small drivers. All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (245 commits) Documentation/security-bugs: Clarify treatment of embargoed information lib: Fix ia64 bootloader linkage MAINTAINERS: Clarify UIO vs UIOVEC maintainer docs/uio: fix a grammar nitpick docs: fpga: document programming fpgas using regions fpga: add devm_fpga_region_create fpga: bridge: add devm_fpga_bridge_create fpga: mgr: add devm_fpga_mgr_create hv_balloon: Replace spin_is_locked() with lockdep sgi-xp: Replace spin_is_locked() with lockdep eeprom: New ee1004 driver for DDR4 memory eeprom: at25: remove unneeded 'at25_remove' w1: IAD Register is yet readable trough iad sys file. Fix snprintf (%u for unsigned, count for max size). misc: mic: scif: remove set but not used variables 'src_dma_addr, dst_dma_addr' misc: mic: fix a DMA pool free failure platform: goldfish: pipe: Add a blank line to separate varibles and code platform: goldfish: pipe: Remove redundant casting platform: goldfish: pipe: Call misc_deregister if init fails platform: goldfish: pipe: Move the file-scope goldfish_pipe_dev variable into the driver state platform: goldfish: pipe: Move the file-scope goldfish_pipe_miscdev variable into the driver state ...
2018-10-26Merge tag 'usb-4.20-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb Pull USB/PHY updates from Greg KH: "Here is the big USB/PHY driver patches for 4.20-rc1 Lots of USB changes in here, primarily in these areas: - typec updates and new drivers - new PHY drivers - dwc2 driver updates and additions (this old core keeps getting added to new devices.) - usbtmc major update based on the industry group coming together and working to add new features and performance to the driver. - USB gadget additions for new features - USB gadget configfs updates - chipidea driver updates - other USB gadget updates - USB serial driver updates - renesas driver updates - xhci driver updates - other tiny USB driver updates All of these have been in linux-next for a while with no reported issues" * tag 'usb-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (229 commits) usb: phy: ab8500: silence some uninitialized variable warnings usb: xhci: tegra: Add genpd support usb: xhci: tegra: Power-off power-domains on removal usbip:vudc: BUG kmalloc-2048 (Not tainted): Poison overwritten usbip: tools: fix atoi() on non-null terminated string USB: misc: appledisplay: fix backlight update_status return code phy: phy-pxa-usb: add a new driver usb: host: add DT bindings for faraday fotg2 usb: host: ohci-at91: fix request of irq for optional gpio usb/early: remove set but not used variable 'remain_length' usb: typec: Fix copy/paste on typec_set_vconn_role() kerneldoc usb: typec: tcpm: Report back negotiated PPS voltage and current USB: core: remove set but not used variable 'udev' usb: core: fix memory leak on port_dev_path allocation USB: net2280: Remove ->disconnect() callback from net2280_pullup() usb: dwc2: disable power_down on rockchip devices usb: gadget: udc: renesas_usb3: add support for r8a77990 dt-bindings: usb: renesas_usb3: add bindings for r8a77990 usb: gadget: udc: renesas_usb3: Add r8a774a1 support USB: serial: cypress_m8: remove set but not used variable 'iflag' ...
2018-10-24Merge tag 'docs-4.20' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "This is a fairly typical cycle for documentation. There's some welcome readability improvements for the formatted output, some LICENSES updates including the addition of the ISC license, the removal of the unloved and unmaintained 00-INDEX files, the deprecated APIs document from Kees, more MM docs from Mike Rapoport, and the usual pile of typo fixes and corrections" * tag 'docs-4.20' of git://git.lwn.net/linux: (41 commits) docs: Fix typos in histogram.rst docs: Introduce deprecated APIs list kernel-doc: fix declaration type determination doc: fix a typo in adding-syscalls.rst docs/admin-guide: memory-hotplug: remove table of contents doc: printk-formats: Remove bogus kobject references for device nodes Documentation: preempt-locking: Use better example dm flakey: Document "error_writes" feature docs/completion.txt: Fix a couple of punctuation nits LICENSES: Add ISC license text LICENSES: Add note to CDDL-1.0 license that it should not be used docs/core-api: memory-hotplug: add some details about locking internals docs/core-api: rename memory-hotplug-notifier to memory-hotplug docs: improve readability for people with poorer eyesight yama: clarify ptrace_scope=2 in Yama documentation docs/vm: split memory hotplug notifier description to Documentation/core-api docs: move memory hotplug description into admin-guide/mm doc: Fix acronym "FEKEK" in ecryptfs docs: fix some broken documentation references iommu: Fix passthrough option documentation ...
2018-10-24Merge tag 'ext4_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: - further restructure ext4 documentation - fix up ext4's delayed allocation for bigalloc file systems - fix up some syzbot-detected races in EXT4_IOC_MOVE_EXT, EXT4_IOC_SWAP_BOOT, and ext4_remount - ... and a few other miscellaneous bugs and optimizations. * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (21 commits) ext4: fix use-after-free race in ext4_remount()'s error path ext4: cache NULL when both default_acl and acl are NULL docs: promote the ext4 data structures book to top level docs: move ext4 administrative docs to admin-guide/ jbd2: fix use after free in jbd2_log_do_checkpoint() ext4: propagate error from dquot_initialize() in EXT4_IOC_FSSETXATTR ext4: fix setattr project check in fssetxattr ioctl docs: make ext4 readme tables readable docs: fix ext4 documentation table formatting problems docs: generate a separate ext4 pdf file from the documentation ext4: convert fault handler to use vm_fault_t type ext4: initialize retries variable in ext4_da_write_inline_data_begin() ext4: fix EXT4_IOC_SWAP_BOOT ext4: fix build error when DX_DEBUG is defined ext4: fix argument checking in EXT4_IOC_MOVE_EXT ext4: fix reserved cluster accounting at page invalidation time ext4: adjust reserved cluster count when removing extents ext4: reduce reserved cluster count by number of allocated clusters ext4: fix reserved cluster accounting at delayed write time ext4: add new pending reservation mechanism ...
2018-10-24Merge branch 'next-general' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security subsystem updates from James Morris: "In this patchset, there are a couple of minor updates, as well as some reworking of the LSM initialization code from Kees Cook (these prepare the way for ordered stackable LSMs, but are a valuable cleanup on their own)" * 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: LSM: Don't ignore initialization failures LSM: Provide init debugging infrastructure LSM: Record LSM name in struct lsm_info LSM: Convert security_initcall() into DEFINE_LSM() vmlinux.lds.h: Move LSM_TABLE into INIT_DATA LSM: Convert from initcall to struct lsm_info LSM: Remove initcall tracing LSM: Rename .security_initcall section to .lsm_info vmlinux.lds.h: Avoid copy/paste of security_init section LSM: Correctly announce start of LSM initialization security: fix LSM description location keys: Fix the use of the C++ keyword "private" in uapi/linux/keyctl.h seccomp: remove unnecessary unlikely() security: tomoyo: Fix obsolete function security/capabilities: remove check for -EINVAL
2018-10-23Merge branch 'x86-paravirt-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 paravirt updates from Ingo Molnar: "Two main changes: - Remove no longer used parts of the paravirt infrastructure and put large quantities of paravirt ops under a new config option PARAVIRT_XXL=y, which is selected by XEN_PV only. (Joergen Gross) - Enable PV spinlocks on Hyperv (Yi Sun)" * 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/hyperv: Enable PV qspinlock for Hyper-V x86/hyperv: Add GUEST_IDLE_MSR support x86/paravirt: Clean up native_patch() x86/paravirt: Prevent redefinition of SAVE_FLAGS macro x86/xen: Make xen_reservation_lock static x86/paravirt: Remove unneeded mmu related paravirt ops bits x86/paravirt: Move the Xen-only pv_mmu_ops under the PARAVIRT_XXL umbrella x86/paravirt: Move the pv_irq_ops under the PARAVIRT_XXL umbrella x86/paravirt: Move the Xen-only pv_cpu_ops under the PARAVIRT_XXL umbrella x86/paravirt: Move items in pv_info under PARAVIRT_XXL umbrella x86/paravirt: Introduce new config option PARAVIRT_XXL x86/paravirt: Remove unused paravirt bits x86/paravirt: Use a single ops structure x86/paravirt: Remove clobbers from struct paravirt_patch_site x86/paravirt: Remove clobbers parameter from paravirt patch functions x86/paravirt: Make paravirt_patch_call() and paravirt_patch_jmp() static x86/xen: Add SPDX identifier in arch/x86/xen files x86/xen: Link platform-pci-unplug.o only if CONFIG_XEN_PVHVM x86/xen: Move pv specific parts of arch/x86/xen/mmu.c to mmu_pv.c x86/xen: Move pv irq related functions under CONFIG_XEN_PV umbrella
2018-10-23Documentation/security-bugs: Clarify treatment of embargoed informationWill Deacon
The Linux kernel security team has been accused of rejecting the idea of security embargoes. This is incorrect, and could dissuade people from reporting security issues to us under the false assumption that the issue would leak prematurely. Clarify the handling of embargoed information in our process documentation. Co-developed-by: Ingo Molnar <mingo@kernel.org> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Laura Abbott <labbott@redhat.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-23Merge branch 'perf-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Ingo Molnar: "The main updates in this cycle were: - Lots of perf tooling changes too voluminous to list (big perf trace and perf stat improvements, lots of libtraceevent reorganization, etc.), so I'll list the authors and refer to the changelog for details: Benjamin Peterson, Jérémie Galarneau, Kim Phillips, Peter Zijlstra, Ravi Bangoria, Sangwon Hong, Sean V Kelley, Steven Rostedt, Thomas Gleixner, Ding Xiang, Eduardo Habkost, Thomas Richter, Andi Kleen, Sanskriti Sharma, Adrian Hunter, Tzvetomir Stoyanov, Arnaldo Carvalho de Melo, Jiri Olsa. ... with the bulk of the changes written by Jiri Olsa, Tzvetomir Stoyanov and Arnaldo Carvalho de Melo. - Continued intel_rdt work with a focus on playing well with perf events. This also imported some non-perf RDT work due to dependencies. (Reinette Chatre) - Implement counter freezing for Arch Perfmon v4 (Skylake and newer). This allows to speed up the PMI handler by avoiding unnecessary MSR writes and make it more accurate. (Andi Kleen) - kprobes cleanups and simplification (Masami Hiramatsu) - Intel Goldmont PMU updates (Kan Liang) - ... plus misc other fixes and updates" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (155 commits) kprobes/x86: Use preempt_enable() in optimized_callback() x86/intel_rdt: Prevent pseudo-locking from using stale pointers kprobes, x86/ptrace.h: Make regs_get_kernel_stack_nth() not fault on bad stack perf/x86/intel: Export mem events only if there's PEBS support x86/cpu: Drop pointless static qualifier in punit_dev_state_show() x86/intel_rdt: Fix initial allocation to consider CDP x86/intel_rdt: CBM overlap should also check for overlap with CDP peer x86/intel_rdt: Introduce utility to obtain CDP peer tools lib traceevent, perf tools: Move struct tep_handler definition in a local header file tools lib traceevent: Separate out tep_strerror() for strerror_r() issues perf python: More portable way to make CFLAGS work with clang perf python: Make clang_has_option() work on Python 3 perf tools: Free temporary 'sys' string in read_event_files() perf tools: Avoid double free in read_event_file() perf tools: Free 'printk' string in parse_ftrace_printk() perf tools: Cleanup trace-event-info 'tdata' leak perf strbuf: Match va_{add,copy} with va_end perf test: S390 does not support watchpoints in test 22 perf auxtrace: Include missing asm/bitsperlong.h to get BITS_PER_LONG tools include: Adopt linux/bits.h ...
2018-10-23Merge 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 biggest change in this cycle is the conclusion of the big 'simplify RCU to two primary flavors' consolidation work - i.e. there's a single RCU flavor for any kernel variant (PREEMPT and !PREEMPT): - Consolidate the RCU-bh, RCU-preempt, and RCU-sched flavors into a single flavor similar to RCU-sched in !PREEMPT kernels and into a single flavor similar to RCU-preempt (but also waiting on preempt-disabled sequences of code) in PREEMPT kernels. This branch also includes a refactoring of rcu_{nmi,irq}_{enter,exit}() from Byungchul Park. - Now that there is only one RCU flavor in any given running kernel, the many "rsp" pointers are no longer required, and this cleanup series removes them. - This branch carries out additional cleanups made possible by the RCU flavor consolidation, including inlining now-trivial functions, updating comments and definitions, and removing now-unneeded rcutorture scenarios. - Now that there is only one flavor of RCU in any running kernel, there is also only on rcu_data structure per CPU. This means that the rcu_dynticks structure can be merged into the rcu_data structure, a task taken on by this branch. This branch also contains a -rt-related fix from Mike Galbraith. There were also other updates: - Documentation updates, including some good-eye catches from Joel Fernandes. - SRCU updates, most notably changes enabling call_srcu() to be invoked very early in the boot sequence. - Torture-test updates, including some preliminary work towards making rcutorture better able to find problems that result in insufficient grace-period forward progress. - Initial changes to RCU to better promote forward progress of grace periods, including fixing a bug found by Marius Hillenbrand and David Woodhouse, with the fix suggested by Peter Zijlstra" * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (140 commits) srcu: Make early-boot call_srcu() reuse workqueue lists rcutorture: Test early boot call_srcu() srcu: Make call_srcu() available during very early boot rcu: Convert rcu_state.ofl_lock to raw_spinlock_t rcu: Remove obsolete ->dynticks_fqs and ->cond_resched_completed rcu: Switch ->dynticks to rcu_data structure, remove rcu_dynticks rcu: Switch dyntick nesting counters to rcu_data structure rcu: Switch urgent quiescent-state requests to rcu_data structure rcu: Switch lazy counts to rcu_data structure rcu: Switch last accelerate/advance to rcu_data structure rcu: Switch ->tick_nohz_enabled_snap to rcu_data structure rcu: Merge rcu_dynticks structure into rcu_data structure rcu: Remove unused rcu_dynticks_snap() from Tiny RCU rcu: Convert "1UL << x" to "BIT(x)" rcu: Avoid resched_cpu() when rescheduling the current CPU rcu: More aggressively enlist scheduler aid for nohz_full CPUs rcu: Compute jiffies_till_sched_qs from other kernel parameters rcu: Provide functions for determining if call_rcu() has been invoked rcu: Eliminate ->rcu_qs_ctr from the rcu_dynticks structure rcu: Motivate Tiny RCU forward progress ...
2018-10-23Merge tag 'pm-4.20-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "These make hibernation on 32-bit x86 systems work in all of the cases in which it works on 64-bit x86 ones, update the menu cpuidle governor and the "polling" state to make them more efficient, add more hardware support to cpufreq drivers and fix issues with some of them, fix a bug in the conservative cpufreq governor, fix the operating performance points (OPP) framework and make it more stable, update the devfreq subsystem to take changes in the APIs used by into account and clean up some things all over. Specifics: - Backport hibernation bug fixes from x86-64 to x86-32 and consolidate hibernation handling on x86 to allow 32-bit systems to work in all of the cases in which 64-bit ones work (Zhimin Gu, Chen Yu). - Fix hibernation documentation (Vladimir D. Seleznev). - Update the menu cpuidle governor to fix a couple of issues with it, make it more efficient in some cases and clean it up (Rafael Wysocki). - Rework the cpuidle polling state implementation to make it more efficient (Rafael Wysocki). - Clean up the cpuidle core somewhat (Fieah Lim). - Fix the cpufreq conservative governor to take policy limits into account properly in some cases (Rafael Wysocki). - Add support for retrieving guaranteed performance information to the ACPI CPPC library and make the intel_pstate driver use it to expose the CPU base frequency via sysfs on systems with the hardware-managed P-states (HWP) feature enabled (Srinivas Pandruvada). - Fix clang warning in the CPPC cpufreq driver (Nathan Chancellor). - Get rid of device_node.name printing from cpufreq (Rob Herring). - Remove unnecessary unlikely() from the cpufreq core (Igor Stoppa). - Add support for the r8a7744 SoC to the cpufreq-dt driver (Biju Das). - Update the dt-platdev cpufreq driver to allow RK3399 to have separate tunables per cluster (Dmitry Torokhov). - Fix the dma_alloc_coherent() usage in the tegra186 cpufreq driver (Christoph Hellwig). - Make the imx6q cpufreq driver read OCOTP through nvmem for imx6ul/imx6ull (Anson Huang). - Fix several bugs in the operating performance points (OPP) framework and make it more stable (Viresh Kumar, Dave Gerlach). - Update the devfreq subsystem to take changes in the APIs used by into account, fix some issues with it and make it stop print device_node.name directly (Bjorn Andersson, Enric Balletbo i Serra, Matthias Kaehlcke, Rob Herring, Vincent Donnefort, zhong jiang). - Prepare the generic power domains (genpd) framework for dealing with domains containing CPUs (Ulf Hansson). - Prevent sysfs attributes representing low-power S0 residency counters from being exposed if low-power S0 support is not indicated in ACPI FADT (Rajneesh Bhardwaj). - Get rid of custom CPU features macros for Intel CPUs from the intel_idle and RAPL drivers (Andy Shevchenko). - Update the tasks freezer to list tasks that refused to freeze and caused a system transition to a sleep state to be aborted (Todd Brandt). - Update the pm-graph set of tools to v5.2 (Todd Brandt). - Fix some issues in the cpupower utility (Anders Roxell, Prarit Bhargava)" * tag 'pm-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (73 commits) PM / Domains: Document flags for genpd PM / Domains: Deal with multiple states but no governor in genpd PM / Domains: Don't treat zero found compatible idle states as an error cpuidle: menu: Avoid computations when result will be discarded cpuidle: menu: Drop redundant comparison cpufreq: tegra186: don't pass GFP_DMA32 to dma_alloc_coherent() cpufreq: conservative: Take limits changes into account properly Documentation: intel_pstate: Add base_frequency information cpufreq: intel_pstate: Add base_frequency attribute ACPI / CPPC: Add support for guaranteed performance cpuidle: menu: Simplify checks related to the polling state PM / tools: sleepgraph and bootgraph: upgrade to v5.2 PM / tools: sleepgraph: first batch of v5.2 changes cpupower: Fix coredump on VMWare cpupower: Fix AMD Family 0x17 msr_pstate size cpufreq: imx6q: read OCOTP through nvmem for imx6ul/imx6ull cpufreq: dt-platdev: allow RK3399 to have separate tunables per cluster cpuidle: poll_state: Revise loop termination condition cpuidle: menu: Move the latency_req == 0 special case check cpuidle: menu: Avoid computations for very close timers ...
2018-10-16Documentation: intel_pstate: Add base_frequency informationSrinivas Pandruvada
Updated documentation to explain base_frequency attribute. Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-10-12docs/admin-guide: memory-hotplug: remove table of contentsMike Rapoport
Remove "manual" table of contents and leave only the ReST tag so that Sphinx will take care of TOC generation. Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-10-10LSM: Provide init debugging infrastructureKees Cook
Booting with "lsm.debug" will report future details on how LSM ordering decisions are being made. Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: John Johansen <john.johansen@canonical.com> Reviewed-by: James Morris <james.morris@microsoft.com> Signed-off-by: James Morris <james.morris@microsoft.com>
2018-10-09x86/hyperv: Enable PV qspinlock for Hyper-VYi Sun
Implement the required wait and kick callbacks to support PV spinlocks in Hyper-V guests. [ tglx: Document the requirement for disabling interrupts in the wait() callback. Remove goto and unnecessary includes. Add prototype for hv_vcpu_is_preempted(). Adapted to pending paravirt changes. ] Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Michael Kelley (EOSG) <Michael.H.Kelley@microsoft.com> Cc: chao.p.peng@intel.com Cc: chao.gao@intel.com Cc: isaku.yamahata@intel.com Cc: tianyu.lan@microsoft.com Link: https://lkml.kernel.org/r/1538987374-51217-3-git-send-email-yi.y.sun@linux.intel.com
2018-10-07yama: clarify ptrace_scope=2 in Yama documentationYves-Alexis Perez
Current phrasing is ambiguous since it's unclear if attaching to a children through PTRACE_TRACEME requires CAP_SYS_PTRACE. Rephrase the sentence to make that clear. Signed-off-by: Yves-Alexis Perez <corsac@corsac.net> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-10-07docs/vm: split memory hotplug notifier description to Documentation/core-apiMike Rapoport
The memory hotplug notifier description is about kernel internals rather than admin/user visible API. Place it appropriately. Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-10-07docs: move memory hotplug description into admin-guide/mmMike Rapoport
The memory hotplug description in Documentation/memory-hotplug.txt is already formatted as ReST and can be easily added to admin-guide/mm section. While on it, slightly update formatting to make it consistent with the doc-guide. Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-10-05docs: move ext4 administrative docs to admin-guide/Darrick J. Wong
Move the ext4 mount option and other administrative stuff to the Linux administrator's guide. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2018-10-03powerpc: Wire up memtestChristophe Leroy
Add call to early_memtest() so that kernel compiled with CONFIG_MEMTEST really perform memtest at startup when requested via 'memtest' boot parameter. Tested-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-02usb: hub: try old enumeration scheme first for high speed devicesZeng Tao
The new scheme is required just to support legacy low and full-speed devices. For high speed devices, it will slower the enumeration speed. So in this patch we try the "old" enumeration scheme first for high speed devices, and this is what Windows does since Windows 8. Signed-off-by: Zeng Tao <prime.zeng@hisilicon.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Reviewed-by: Roger Quadros <rogerq@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-02x86/earlyprintk: Add a force option for pciserial deviceFeng Tang
The "pciserial" earlyprintk variant helps much on many modern x86 platforms, but unfortunately there are still some platforms with PCI UART devices which have the wrong PCI class code. In that case, the current class code check does not allow for them to be used for logging. Add a sub-option "force" which overrides the class code check and thus the use of such device can be enforced. [ bp: massage formulations. ] Suggested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Feng Tang <feng.tang@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Stuart R . Anderson" <stuart.r.anderson@intel.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: David Rientjes <rientjes@google.com> Cc: Feng Tang <feng.tang@intel.com> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: H Peter Anvin <hpa@linux.intel.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kai-Heng Feng <kai.heng.feng@canonical.com> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thymo van Beers <thymovanbeers@gmail.com> Cc: alan@linux.intel.com Cc: linux-doc@vger.kernel.org Link: http://lkml.kernel.org/r/20181002164921.25833-1-feng.tang@intel.com
2018-10-02Merge branch 'for-mingo' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu Pull v4.20 RCU changes from Paul E. McKenney: - Documentation updates, including some good-eye catches from Joel Fernandes. - SRCU updates, most notably changes enabling call_srcu() to be invoked very early in the boot sequence. - Torture-test updates, including some preliminary work towards making rcutorture better able to find problems that result in insufficient grace-period forward progress. - Consolidate the RCU-bh, RCU-preempt, and RCU-sched flavors into a single flavor similar to RCU-sched in !PREEMPT kernels and into a single flavor similar to RCU-preempt (but also waiting on preempt-disabled sequences of code) in PREEMPT kernels. This branch also includes a refactoring of rcu_{nmi,irq}_{enter,exit}() from Byungchul Park. - Now that there is only one RCU flavor in any given running kernel, the many "rsp" pointers are no longer required, and this cleanup series removes them. - This branch carries out additional cleanups made possible by the RCU flavor consolidation, including inlining how-trivial functions, updating comments and definitions, and removing now-unneeded rcutorture scenarios. - Initial changes to RCU to better promote forward progress of grace periods, including fixing a bug found by Marius Hillenbrand and David Woodhouse, with the fix suggested by Peter Zijlstra. - Now that there is only one flavor of RCU in any running kernel, there is also only on rcu_data structure per CPU. This means that the rcu_dynticks structure can be merged into the rcu_data structure, a task taken on by this branch. This branch also contains a -rt-related fix from Mike Galbraith. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-02perf/x86/intel: Add a separate Arch Perfmon v4 PMI handlerAndi Kleen
Implements counter freezing for Arch Perfmon v4 (Skylake and newer). This allows to speed up the PMI handler by avoiding unnecessary MSR writes and make it more accurate. The Arch Perfmon v4 PMI handler is substantially different than the older PMI handler. Differences to the old handler: - It relies on counter freezing, which eliminates several MSR writes from the PMI handler and lowers the overhead significantly. It makes the PMI handler more accurate, as all counters get frozen atomically as soon as any counter overflows. So there is much less counting of the PMI handler itself. With the freezing we don't need to disable or enable counters or PEBS. Only BTS which does not support auto-freezing still needs to be explicitly managed. - The PMU acking is done at the end, not the beginning. This makes it possible to avoid manual enabling/disabling of the PMU, instead we just rely on the freezing/acking. - The APIC is acked before reenabling the PMU, which avoids problems with LBRs occasionally not getting unfreezed on Skylake. - Looping is only needed to workaround a corner case which several PMIs are very close to each other. For common cases, the counters are freezed during PMI handler. It doesn't need to do re-check. This patch: - Adds code to enable v4 counter freezing - Fork <=v3 and >=v4 PMI handlers into separate functions. - Add kernel parameter to disable counter freezing. It took some time to debug counter freezing, so in case there are new problems we added an option to turn it off. Would not expect this to be used until there are new bugs. - Only for big core. The patch for small core will be posted later separately. Performance: When profiling a kernel build on Kabylake with different perf options, measuring the length of all NMI handlers using the nmi handler trace point: V3 is without counter freezing. V4 is with counter freezing. The value is the average cost of the PMI handler. (lower is better) perf options ` V3(ns) V4(ns) delta -c 100000 1088 894 -18% -g -c 100000 1862 1646 -12% --call-graph lbr -c 100000 3649 3367 -8% --c.g. dwarf -c 100000 2248 1982 -12% Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: acme@kernel.org Link: http://lkml.kernel.org/r/1533712328-2834-2-git-send-email-kan.liang@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-01Merge branch 'for-joerg/arm-smmu/updates' of ↵Joerg Roedel
git://git.kernel.org/pub/scm/linux/kernel/git/will/linux into arm/smmu
2018-10-01Merge tag 'v4.19-rc6' into for-4.20/blockJens Axboe
Merge -rc6 in, for two reasons: 1) Resolve a trivial conflict in the blk-mq-tag.c documentation 2) A few important regression fixes went into upstream directly, so they aren't in the 4.20 branch. Signed-off-by: Jens Axboe <axboe@kernel.dk> * tag 'v4.19-rc6': (780 commits) Linux 4.19-rc6 MAINTAINERS: fix reference to moved drivers/{misc => auxdisplay}/panel.c cpufreq: qcom-kryo: Fix section annotations perf/core: Add sanity check to deal with pinned event failure xen/blkfront: correct purging of persistent grants Revert "xen/blkfront: When purging persistent grants, keep them in the buffer" selftests/powerpc: Fix Makefiles for headers_install change blk-mq: I/O and timer unplugs are inverted in blktrace dax: Fix deadlock in dax_lock_mapping_entry() x86/boot: Fix kexec booting failure in the SEV bit detection code bcache: add separate workqueue for journal_write to avoid deadlock drm/amd/display: Fix Edid emulation for linux drm/amd/display: Fix Vega10 lightup on S3 resume drm/amdgpu: Fix vce work queue was not cancelled when suspend Revert "drm/panel: Add device_link from panel device to DRM device" xen/blkfront: When purging persistent grants, keep them in the buffer clocksource/drivers/timer-atmel-pit: Properly handle error cases block: fix deadline elevator drain for zoned block devices ACPI / hotplug / PCI: Don't scan for non-hotplug bridges if slot is not bridge drm/syncobj: Don't leak fences when WAIT_FOR_SUBMIT is set ... Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-10-01iommu: Add "iommu.strict" command line optionZhen Lei
Add a generic command line option to enable lazy unmapping via IOVA flush queues, which will initally be suuported by iommu-dma. This echoes the semantics of "intel_iommu=strict" (albeit with the opposite default value), but in the driver-agnostic fashion of "iommu.passthrough". Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> [rm: move handling out of SMMUv3 driver, clean up documentation] Signed-off-by: Robin Murphy <robin.murphy@arm.com> [will: dropped broken printk when parsing command-line option] Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-09-21blkcg: associate writeback bios with a blkgDennis Zhou (Facebook)
One of the goals of this series is to remove a separate reference to the css of the bio. This can and should be accessed via bio_blkcg. In this patch, the wbc_init_bio call is changed such that it must be called after a queue has been associated with the bio. Signed-off-by: Dennis Zhou <dennisszhou@gmail.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-09-20iommu: Fix passthrough option documentationRobin Murphy
Document that the default for "iommu.passthrough" is now configurable. Fixes: 58d1131777a4 ("iommu: Add config option to set passthrough as default") Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-09-14xen/balloon: add runtime control for scrubbing ballooned out pagesMarek Marczykowski-Górecki
Scrubbing pages on initial balloon down can take some time, especially in nested virtualization case (nested EPT is slow). When HVM/PVH guest is started with memory= significantly lower than maxmem=, all the extra pages will be scrubbed before returning to Xen. But since most of them weren't used at all at that point, Xen needs to populate them first (from populate-on-demand pool). In nested virt case (Xen inside KVM) this slows down the guest boot by 15-30s with just 1.5GB needed to be returned to Xen. Add runtime parameter to enable/disable it, to allow initially disabling scrubbing, then enable it back during boot (for example in initramfs). Such usage relies on assumption that a) most pages ballooned out during initial boot weren't used at all, and b) even if they were, very few secrets are in the guest at that time (before any serious userspace kicks in). Convert CONFIG_XEN_SCRUB_PAGES to CONFIG_XEN_SCRUB_PAGES_DEFAULT (also enabled by default), controlling default value for the new runtime switch. Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2018-09-09Drop all 00-INDEX files from Documentation/Henrik Austad
This is a respin with a wider audience (all that get_maintainer returned) and I know this spams a *lot* of people. Not sure what would be the correct way, so my apologies for ruining your inbox. The 00-INDEX files are supposed to give a summary of all files present in a directory, but these files are horribly out of date and their usefulness is brought into question. Often a simple "ls" would reveal the same information as the filenames are generally quite descriptive as a short introduction to what the file covers (it should not surprise anyone what Documentation/sched/sched-design-CFS.txt covers) A few years back it was mentioned that these files were no longer really needed, and they have since then grown further out of date, so perhaps it is time to just throw them out. A short status yields the following _outdated_ 00-INDEX files, first counter is files listed in 00-INDEX but missing in the directory, last is files present but not listed in 00-INDEX. List of outdated 00-INDEX: Documentation: (4/10) Documentation/sysctl: (0/1) Documentation/timers: (1/0) Documentation/blockdev: (3/1) Documentation/w1/slaves: (0/1) Documentation/locking: (0/1) Documentation/devicetree: (0/5) Documentation/power: (1/1) Documentation/powerpc: (0/5) Documentation/arm: (1/0) Documentation/x86: (0/9) Documentation/x86/x86_64: (1/1) Documentation/scsi: (4/4) Documentation/filesystems: (2/9) Documentation/filesystems/nfs: (0/2) Documentation/cgroup-v1: (0/2) Documentation/kbuild: (0/4) Documentation/spi: (1/0) Documentation/virtual/kvm: (1/0) Documentation/scheduler: (0/2) Documentation/fb: (0/1) Documentation/block: (0/1) Documentation/networking: (6/37) Documentation/vm: (1/3) Then there are 364 subdirectories in Documentation/ with several files that are missing 00-INDEX alltogether (and another 120 with a single file and no 00-INDEX). I don't really have an opinion to whether or not we /should/ have 00-INDEX, but the above 00-INDEX should either be removed or be kept up to date. If we should keep the files, I can try to keep them updated, but I rather not if we just want to delete them anyway. As a starting point, remove all index-files and references to 00-INDEX and see where the discussion is going. Signed-off-by: Henrik Austad <henrik@austad.us> Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Just-do-it-by: Steven Rostedt <rostedt@goodmis.org> Reviewed-by: Jens Axboe <axboe@kernel.dk> Acked-by: Paul Moore <paul@paul-moore.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Mark Brown <broonie@kernel.org> Acked-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: [Almost everybody else] Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-09-09Merge tag 'for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random Pull random driver fix from Ted Ts'o: "Fix things so the choice of whether or not to trust RDRAND to initialize the CRNG is configurable via the boot option random.trust_cpu={on,off}" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random: random: make CPU trust a boot parameter
2018-09-01random: make CPU trust a boot parameterKees Cook
Instead of forcing a distro or other system builder to choose at build time whether the CPU is trusted for CRNG seeding via CONFIG_RANDOM_TRUST_CPU, provide a boot-time parameter for end users to control the choice. The CONFIG will set the default state instead. Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2018-08-31Documentation/l1tf: Fix small spelling typoSalvatore Bonaccorso
Fix small typo (wiil -> will) in the "3.4. Nested virtual machines" section. Fixes: 5b76a3cff011 ("KVM: VMX: Tell the nested hypervisor to skip L1D flush on vmentry") Cc: linux-kernel@vger.kernel.org Cc: Jonathan Corbet <corbet@lwn.net> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Tony Luck <tony.luck@intel.com> Cc: linux-doc@vger.kernel.org Cc: trivial@kernel.org Signed-off-by: Salvatore Bonaccorso <carnil@debian.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-08-30Merge branches 'doc.2018.08.30a', 'dynticks.2018.08.30b', 'srcu.2018.08.30b' ↵Paul E. McKenney
and 'torture.2018.08.29a' into HEAD doc.2018.08.30a: Documentation updates dynticks.2018.08.30b: RCU flavor consolidation updates and cleanups srcu.2018.08.30b: SRCU updates torture.2018.08.29a: Torture-test updates
2018-08-30rcu: Compute jiffies_till_sched_qs from other kernel parametersPaul E. McKenney
The jiffies_till_sched_qs value used to determine how old a grace period must be before RCU enlists the help of the scheduler to force a quiescent state on the holdout CPU. Currently, this defaults to HZ/10 regardless of system size and may be set only at boot time. This can be a problem for very large systems, because if the values of the jiffies_till_first_fqs and jiffies_till_next_fqs kernel parameters are left at their defaults, they are calculated to increase as the number of CPUs actually configured on the system increases. Thus, on a sufficiently large system, RCU would enlist the help of the scheduler before the grace-period kthread had a chance to scan for idle CPUs, which wastes CPU time. This commit therefore allows jiffies_till_sched_qs to be set, if desired, but if left as default, computes is as jiffies_till_first_fqs plus twice jiffies_till_next_fqs, thus allowing three force-quiescent-state scans for idle CPUs. This scales with the number of CPUs, providing sensible default values. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-30rcu: Stop testing RCU-bh and RCU-schedPaul E. McKenney
Now that the RCU-bh and RCU-sched update-side functions are simple wrappers around their RCU counterparts, there isn't a whole lot of point in testing them. This commit therefore removes the self-test capability and removes the corresponding kernel-boot parameters. It also updates the various rcutorture .boot files to remove the kernel boot parameters that call for testing RCU-bh and RCU-sched. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-30doc: Update removal of RCU-bh/sched update machineryPaul E. McKenney
The RCU-bh update API is now defined in terms of that of RCU-bh and RCU-sched, so this commit updates the documentation accordingly. In addition, although RCU-sched persists in !PREEMPT kernels, in the PREEMPT case its update API is now defined in terms of that of RCU-preempt, so this commit also updates the documentation accordingly. While in the area, this commit removes the documentation for the now-obsolete synchronize_rcu_mult() and clarifies the Tasks RCU documentation. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-24Merge tag 'iommu-updates-v4.19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu Pull IOMMU updates from Joerg Roedel: - PASID table handling updates for the Intel VT-d driver. It implements a global PASID space now so that applications usings multiple devices will just have one PASID. - A new config option to make iommu passthroug mode the default. - New sysfs attribute for iommu groups to export the type of the default domain. - A debugfs interface (for debug only) usable by IOMMU drivers to export internals to user-space. - R-Car Gen3 SoCs support for the ipmmu-vmsa driver - The ARM-SMMU now aborts transactions from unknown devices and devices not attached to any domain. - Various cleanups and smaller fixes all over the place. * tag 'iommu-updates-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (42 commits) iommu/omap: Fix cache flushes on L2 table entries iommu: Remove the ->map_sg indirection iommu/arm-smmu-v3: Abort all transactions if SMMU is enabled in kdump kernel iommu/arm-smmu-v3: Prevent any devices access to memory without registration iommu/ipmmu-vmsa: Don't register as BUS IOMMU if machine doesn't have IPMMU-VMSA iommu/ipmmu-vmsa: Clarify supported platforms iommu/ipmmu-vmsa: Fix allocation in atomic context iommu: Add config option to set passthrough as default iommu: Add sysfs attribyte for domain type iommu/arm-smmu-v3: sync the OVACKFLG to PRIQ consumer register iommu/arm-smmu: Error out only if not enough context interrupts iommu/io-pgtable-arm-v7s: Abort allocation when table address overflows the PTE iommu/io-pgtable-arm: Fix pgtable allocation in selftest iommu/vt-d: Remove the obsolete per iommu pasid tables iommu/vt-d: Apply per pci device pasid table in SVA iommu/vt-d: Allocate and free pasid table iommu/vt-d: Per PCI device pasid table interfaces iommu/vt-d: Add for_each_device_domain() helper iommu/vt-d: Move device_domain_info to header iommu/vt-d: Apply global PASID in SVA ...