lwn.git/include/uapi, branch docs-5.13

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

2021-03-04T19:26:17+00:00

Pull KVM fixes from Paolo Bonzini: - Doc fixes - selftests fixes - Add runstate information to the new Xen support - Allow compiling out the Xen interface - 32-bit PAE without EPT bugfix - NULL pointer dereference bugfix * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: SVM: Clear the CR4 register on reset KVM: x86/xen: Add support for vCPU runstate information KVM: x86/xen: Fix return code when clearing vcpu_info and vcpu_time_info selftests: kvm: Mmap the entire vcpu mmap area KVM: Documentation: Fix index for KVM_CAP_PPC_DAWR1 KVM: x86: allow compiling out the Xen hypercall interface KVM: xen: flush deferred static key before checking it KVM: x86/mmu: Set SPTE_AD_WRPROT_ONLY_MASK if and only if PML is enabled KVM: x86: hyper-v: Fix Hyper-V context null-ptr-deref KVM: x86: remove misplaced comment on active_mmu_pages KVM: Documentation: rectify rst markup in kvm_run->flags Documentation: kvm: fix messy conversion from .txt to .rst

KVM: x86/xen: Add support for vCPU runstate information

2021-03-02T19:30:54+00:00

This is how Xen guests do steal time accounting. The hypervisor records the amount of time spent in each of running/runnable/blocked/offline states. In the Xen accounting, a vCPU is still in state RUNSTATE_running while in Xen for a hypercall or I/O trap, etc. Only if Xen explicitly schedules does the state become RUNSTATE_blocked. In KVM this means that even when the vCPU exits the kvm_run loop, the state remains RUNSTATE_running. The VMM can explicitly set the vCPU to RUNSTATE_blocked by using the KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_CURRENT attribute, and can also use KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADJUST to retrospectively add a given amount of time to the blocked state and subtract it from the running state. The state_entry_time corresponds to get_kvmclock_ns() at the time the vCPU entered the current state, and the total times of all four states should always add up to state_entry_time. Co-developed-by: Joao Martins Signed-off-by: Joao Martins Signed-off-by: David Woodhouse Message-Id: <20210301125309.874953-2-dwmw2@infradead.org> Signed-off-by: Paolo Bonzini

Merge tag 'io_uring-worker.v3-2021-02-25' of git://git.kernel.dk/linux-block

2021-02-27T16:29:02+00:00

Pull io_uring thread rewrite from Jens Axboe: "This converts the io-wq workers to be forked off the tasks in question instead of being kernel threads that assume various bits of the original task identity. This kills > 400 lines of code from io_uring/io-wq, and it's the worst part of the code. We've had several bugs in this area, and the worry is always that we could be missing some pieces for file types doing unusual things (recent /dev/tty example comes to mind, userfaultfd reads installing file descriptors is another fun one... - both of which need special handling, and I bet it's not the last weird oddity we'll find). With these identical workers, we can have full confidence that we're never missing anything. That, in itself, is a huge win. Outside of that, it's also more efficient since we're not wasting space and code on tracking state, or switching between different states. I'm sure we're going to find little things to patch up after this series, but testing has been pretty thorough, from the usual regression suite to production. Any issue that may crop up should be manageable. There's also a nice series of further reductions we can do on top of this, but I wanted to get the meat of it out sooner rather than later. The general worry here isn't that it's fundamentally broken. Most of the little issues we've found over the last week have been related to just changes in how thread startup/exit is done, since that's the main difference between using kthreads and these kinds of threads. In fact, if all goes according to plan, I want to get this into the 5.10 and 5.11 stable branches as well. That said, the changes outside of io_uring/io-wq are: - arch setup, simple one-liner to each arch copy_thread() implementation. - Removal of net and proc restrictions for io_uring, they are no longer needed or useful" * tag 'io_uring-worker.v3-2021-02-25' of git://git.kernel.dk/linux-block: (30 commits) io-wq: remove now unused IO_WQ_BIT_ERROR io_uring: fix SQPOLL thread handling over exec io-wq: improve manager/worker handling over exec io_uring: ensure SQPOLL startup is triggered before error shutdown io-wq: make buffered file write hashed work map per-ctx io-wq: fix race around io_worker grabbing io-wq: fix races around manager/worker creation and task exit io_uring: ensure io-wq context is always destroyed for tasks arch: ensure parisc/powerpc handle PF_IO_WORKER in copy_thread() io_uring: cleanup ->user usage io-wq: remove nr_process accounting io_uring: flag new native workers with IORING_FEAT_NATIVE_WORKERS net: remove cmsg restriction from io_uring based send/recvmsg calls Revert "proc: don't allow async path resolution of /proc/self components" Revert "proc: don't allow async path resolution of /proc/thread-self components" io_uring: move SQPOLL thread io-wq forked worker io-wq: make io_wq_fork_thread() available to other users io-wq: only remove worker from free_list, if it was there io_uring: remove io_identity io_uring: remove any grabbing of context ...

Merge branch 'akpm' (patches from Andrew)

2021-02-26T17:50:09+00:00

Merge more updates from Andrew Morton: "118 patches: - The rest of MM. Includes kfence - another runtime memory validator. Not as thorough as KASAN, but it has unmeasurable overhead and is intended to be usable in production builds. - Everything else Subsystems affected by this patch series: alpha, procfs, sysctl, misc, core-kernel, MAINTAINERS, lib, bitops, checkpatch, init, coredump, seq_file, gdb, ubsan, initramfs, and mm (thp, cma, vmstat, memory-hotplug, mlock, rmap, zswap, zsmalloc, cleanups, kfence, kasan2, and pagemap2)" * emailed patches from Andrew Morton : (118 commits) MIPS: make userspace mapping young by default initramfs: panic with memory information ubsan: remove overflow checks kgdb: fix to kill breakpoints on initmem after boot scripts/gdb: fix list_for_each x86: fix seq_file iteration for pat/memtype.c seq_file: document how per-entry resources are managed. fs/coredump: use kmap_local_page() init/Kconfig: fix a typo in CC_VERSION_TEXT help text init: clean up early_param_on_off() macro init/version.c: remove Version_ symbol checkpatch: do not apply "initialise globals to 0" check to BPF progs checkpatch: don't warn about colon termination in linker scripts checkpatch: add kmalloc_array_node to unnecessary OOM message check checkpatch: add warning for avoiding .L prefix symbols in assembly files checkpatch: improve TYPECAST_INT_CONSTANT test message checkpatch: prefer ftrace over function entry/exit printks checkpatch: trivial style fixes checkpatch: ignore warning designated initializers using NR_CPUS checkpatch: improve blank line after declaration test ...

include/linux: remove repeated words

2021-02-26T17:41:03+00:00

Drop the doubled word "for" in a comment. {firewire-cdev.h} Drop the doubled word "in" in a comment. {input.h} Drop the doubled word "a" in a comment. {mdev.h} Drop the doubled word "the" in a comment. {ptrace.h} Link: https://lkml.kernel.org/r/20210126232444.22861-1-rdunlap@infradead.org Signed-off-by: Randy Dunlap Cc: Stefan Richter Cc: Dmitry Torokhov Cc: Kirti Wankhede Cc: Oleg Nesterov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

2021-02-25T20:21:08+00:00

Pull virtio updates from Michael Tsirkin: - new vdpa features to allow creation and deletion of new devices - virtio-blk support per-device queue depth - fixes, cleanups all over the place * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (31 commits) virtio-input: add multi-touch support virtio_mmio: fix one typo vdpa/mlx5: fix param validation in mlx5_vdpa_get_config() virtio_net: Fix fall-through warnings for Clang virtio_input: Prevent EV_MSC/MSC_TIMESTAMP loop storm for MT. virtio-blk: support per-device queue depth virtio_vdpa: don't warn when fail to disable vq virtio-pci: introduce modern device module virito-pci-modern: rename map_capability() to vp_modern_map_capability() virtio-pci-modern: introduce helper to get notification offset virtio-pci-modern: introduce helper for getting queue nums virtio-pci-modern: introduce helper for setting/geting queue size virtio-pci-modern: introduce helper to set/get queue_enable virtio-pci-modern: introduce vp_modern_queue_address() virtio-pci-modern: introduce vp_modern_set_queue_vector() virtio-pci-modern: introduce vp_modern_generation() virtio-pci-modern: introduce helpers for setting and getting features virtio-pci-modern: introduce helpers for setting and getting status virtio-pci-modern: introduce helper to set config vector virtio-pci-modern: introduce vp_modern_remove() ...

Merge branch 'akpm' (patches from Andrew)

2021-02-25T00:20:38+00:00

Merge misc updates from Andrew Morton: "A few small subsystems and some of MM. 172 patches. Subsystems affected by this patch series: hexagon, scripts, ntfs, ocfs2, vfs, and mm (slab-generic, slab, slub, debug, pagecache, swap, memcg, pagemap, mprotect, mremap, page-reporting, vmalloc, kasan, pagealloc, memory-failure, hugetlb, vmscan, z3fold, compaction, mempolicy, oom-kill, hugetlbfs, and migration)" * emailed patches from Andrew Morton : (172 commits) mm/migrate: remove unneeded semicolons hugetlbfs: remove unneeded return value of hugetlb_vmtruncate() hugetlbfs: fix some comment typos hugetlbfs: correct some obsolete comments about inode i_mutex hugetlbfs: make hugepage size conversion more readable hugetlbfs: remove meaningless variable avoid_reserve hugetlbfs: correct obsolete function name in hugetlbfs_read_iter() hugetlbfs: use helper macro default_hstate in init_hugetlbfs_fs hugetlbfs: remove useless BUG_ON(!inode) in hugetlbfs_setattr() hugetlbfs: remove special hugetlbfs_set_page_dirty() mm/hugetlb: change hugetlb_reserve_pages() to type bool mm, oom: fix a comment in dump_task() mm/mempolicy: use helper range_in_vma() in queue_pages_test_walk() numa balancing: migrate on fault among multiple bound nodes mm, compaction: make fast_isolate_freepages() stay within zone mm/compaction: fix misbehaviors of fast_find_migrateblock() mm/compaction: correct deferral logic for proactive compaction mm/compaction: remove duplicated VM_BUG_ON_PAGE !PageLocked mm/compaction: remove rcu_read_lock during page compaction z3fold: simplify the zhdr initialization code in init_z3fold_page() ...

numa balancing: migrate on fault among multiple bound nodes

2021-02-24T21:38:34+00:00

Now, NUMA balancing can only optimize the page placement among the NUMA nodes if the default memory policy is used. Because the memory policy specified explicitly should take precedence. But this seems too strict in some situations. For example, on a system with 4 NUMA nodes, if the memory of an application is bound to the node 0 and 1, NUMA balancing can potentially migrate the pages between the node 0 and 1 to reduce cross-node accessing without breaking the explicit memory binding policy. So in this patch, we add MPOL_F_NUMA_BALANCING mode flag to set_mempolicy() when mode is MPOL_BIND. With the flag specified, NUMA balancing will be enabled within the thread to optimize the page placement within the constrains of the specified memory binding policy. With the newly added flag, the NUMA balancing control mechanism becomes, - sysctl knob numa_balancing can enable/disable the NUMA balancing globally. - even if sysctl numa_balancing is enabled, the NUMA balancing will be disabled for the memory areas or applications with the explicit memory policy by default. - MPOL_F_NUMA_BALANCING can be used to enable the NUMA balancing for the applications when specifying the explicit memory policy (MPOL_BIND). Various page placement optimization based on the NUMA balancing can be done with these flags. As the first step, in this patch, if the memory of the application is bound to multiple nodes (MPOL_BIND), and in the hint page fault handler the accessing node are in the policy nodemask, the page will be tried to be migrated to the accessing node to reduce the cross-node accessing. If the newly added MPOL_F_NUMA_BALANCING flag is specified by an application on an old kernel version without its support, set_mempolicy() will return -1 and errno will be set to EINVAL. The application can use this behavior to run on both old and new kernel versions. And if the MPOL_F_NUMA_BALANCING flag is specified for the mode other than MPOL_BIND, set_mempolicy() will return -1 and errno will be set to EINVAL as before. Because we don't support optimization based on the NUMA balancing for these modes. In the previous version of the patch, we tried to reuse MPOL_MF_LAZY for mbind(). But that flag is tied to MPOL_MF_MOVE.*, so it seems not a good API/ABI for the purpose of the patch. And because it's not clear whether it's necessary to enable NUMA balancing for a specific memory area inside an application, so we only add the flag at the thread level (set_mempolicy()) instead of the memory area level (mbind()). We can do that when it become necessary. To test the patch, we run a test case as follows on a 4-node machine with 192 GB memory (48 GB per node). 1. Change pmbench memory accessing benchmark to call set_mempolicy() to bind its memory to node 1 and 3 and enable NUMA balancing. Some related code snippets are as follows, #include #include struct bitmask *bmp; int ret; bmp = numa_parse_nodestring("1,3"); ret = set_mempolicy(MPOL_BIND | MPOL_F_NUMA_BALANCING, bmp->maskp, bmp->size + 1); /* If MPOL_F_NUMA_BALANCING isn't supported, fall back to MPOL_BIND */ if (ret < 0 && errno == EINVAL) ret = set_mempolicy(MPOL_BIND, bmp->maskp, bmp->size + 1); if (ret < 0) { perror("Failed to call set_mempolicy"); exit(-1); } 2. Run a memory eater on node 3 to use 40 GB memory before running pmbench. 3. Run pmbench with 64 processes, the working-set size of each process is 640 MB, so the total working-set size is 64 * 640 MB = 40 GB. The CPU and the memory (as in step 1.) of all pmbench processes is bound to node 1 and 3. So, after CPU usage is balanced, some pmbench processes run on the CPUs of the node 3 will access the memory of the node 1. 4. After the pmbench processes run for 100 seconds, kill the memory eater. Now it's possible for some pmbench processes to migrate their pages from node 1 to node 3 to reduce cross-node accessing. Test results show that, with the patch, the pages can be migrated from node 1 to node 3 after killing the memory eater, and the pmbench score can increase about 17.5%. Link: https://lkml.kernel.org/r/20210120061235.148637-2-ying.huang@intel.com Signed-off-by: "Huang, Ying" Acked-by: Mel Gorman Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Rik van Riel Cc: Johannes Weiner Cc: "Matthew Wilcox (Oracle)" Cc: Dave Hansen Cc: Andi Kleen Cc: Michal Hocko Cc: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge tag 'vfio-v5.12-rc1' of git://github.com/awilliam/linux-vfio

2021-02-24T18:43:40+00:00

Pull VFIO updatesfrom Alex Williamson: - Virtual address update handling (Steve Sistare) - s390/zpci fixes and cleanups (Max Gurtovoy) - Fixes for dirty bitmap handling, non-mdev page pinning, and improved pinned dirty scope tracking (Keqian Zhu) - Batched page pinning enhancement (Daniel Jordan) - Page access permission fix (Alex Williamson) * tag 'vfio-v5.12-rc1' of git://github.com/awilliam/linux-vfio: (21 commits) vfio/type1: Batch page pinning vfio/type1: Prepare for batched pinning with struct vfio_batch vfio/type1: Change success value of vaddr_get_pfn() vfio/type1: Use follow_pte() vfio/pci: remove CONFIG_VFIO_PCI_ZDEV from Kconfig vfio/iommu_type1: Fix duplicate included kthread.h vfio-pci/zdev: fix possible segmentation fault issue vfio-pci/zdev: remove unused vdev argument vfio/pci: Fix handling of pci use accessor return codes vfio/iommu_type1: Mantain a counter for non_pinned_groups vfio/iommu_type1: Fix some sanity checks in detach group vfio/iommu_type1: Populate full dirty when detach non-pinned group vfio/type1: block on invalid vaddr vfio/type1: implement notify callback vfio: iommu driver notify callback vfio/type1: implement interfaces to update vaddr vfio/type1: massage unmap iteration vfio: interfaces to update vaddr vfio/type1: implement unmap all vfio/type1: unmap cleanup ...

Merge tag 'char-misc-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2021-02-24T18:25:37+00:00

Pull char/misc driver updates from Greg KH: "Here is the large set of char/misc/whatever driver subsystem updates for 5.12-rc1. Over time it seems like this tree is collecting more and more tiny driver subsystems in one place, making it easier for those maintainers, which is why this is getting larger. Included in here are: - coresight driver updates - habannalabs driver updates - virtual acrn driver addition (proper acks from the x86 maintainers) - broadcom misc driver addition - speakup driver updates - soundwire driver updates - fpga driver updates - amba driver updates - mei driver updates - vfio driver updates - greybus driver updates - nvmeem driver updates - phy driver updates - mhi driver updates - interconnect driver udpates - fsl-mc bus driver updates - random driver fix - some small misc driver updates (rtsx, pvpanic, etc.) All of these have been in linux-next for a while, with the only reported issue being a merge conflict due to the dfl_device_id addition from the fpga subsystem in here" * tag 'char-misc-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (311 commits) spmi: spmi-pmic-arb: Fix hw_irq overflow Documentation: coresight: Add PID tracing description coresight: etm-perf: Support PID tracing for kernel at EL2 coresight: etm-perf: Clarify comment on perf options ACRN: update MAINTAINERS: mailing list is subscribers-only regmap: sdw-mbq: use MODULE_LICENSE("GPL") regmap: sdw: use no_pm routines for SoundWire 1.2 MBQ regmap: sdw: use _no_pm functions in regmap_read/write soundwire: intel: fix possible crash when no device is detected MAINTAINERS: replace my with email with replacements mhi: Fix double dma free uapi: map_to_7segment: Update example in documentation uio: uio_pci_generic: don't fail probe if pdev->irq equals to IRQ_NOTCONNECTED drivers/misc/vmw_vmci: restrict too big queue size in qp_host_alloc_queue firewire: replace tricky statement by two simple ones vme: make remove callback return void firmware: google: make coreboot driver's remove callback return void firmware: xilinx: Use explicit values for all enum values sample/acrn: Introduce a sample of HSM ioctl interface usage virt: acrn: Introduce an interface for Service VM to control vCPU ...