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2019-09-21Merge tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdmaLinus Torvalds12-734/+675
Pull hmm updates from Jason Gunthorpe: "This is more cleanup and consolidation of the hmm APIs and the very strongly related mmu_notifier interfaces. Many places across the tree using these interfaces are touched in the process. Beyond that a cleanup to the page walker API and a few memremap related changes round out the series: - General improvement of hmm_range_fault() and related APIs, more documentation, bug fixes from testing, API simplification & consolidation, and unused API removal - Simplify the hmm related kconfigs to HMM_MIRROR and DEVICE_PRIVATE, and make them internal kconfig selects - Hoist a lot of code related to mmu notifier attachment out of drivers by using a refcount get/put attachment idiom and remove the convoluted mmu_notifier_unregister_no_release() and related APIs. - General API improvement for the migrate_vma API and revision of its only user in nouveau - Annotate mmu_notifiers with lockdep and sleeping region debugging Two series unrelated to HMM or mmu_notifiers came along due to dependencies: - Allow pagemap's memremap_pages family of APIs to work without providing a struct device - Make walk_page_range() and related use a constant structure for function pointers" * tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (75 commits) libnvdimm: Enable unit test infrastructure compile checks mm, notifier: Catch sleeping/blocking for !blockable kernel.h: Add non_block_start/end() drm/radeon: guard against calling an unpaired radeon_mn_unregister() csky: add missing brackets in a macro for tlb.h pagewalk: use lockdep_assert_held for locking validation pagewalk: separate function pointers from iterator data mm: split out a new pagewalk.h header from mm.h mm/mmu_notifiers: annotate with might_sleep() mm/mmu_notifiers: prime lockdep mm/mmu_notifiers: add a lockdep map for invalidate_range_start/end mm/mmu_notifiers: remove the __mmu_notifier_invalidate_range_start/end exports mm/hmm: hmm_range_fault() infinite loop mm/hmm: hmm_range_fault() NULL pointer bug mm/hmm: fix hmm_range_fault()'s handling of swapped out pages mm/mmu_notifiers: remove unregister_no_release RDMA/odp: remove ib_ucontext from ib_umem RDMA/odp: use mmu_notifier_get/put for 'struct ib_ucontext_per_mm' RDMA/mlx5: Use odp instead of mr->umem in pagefault_mr RDMA/mlx5: Use ib_umem_start instead of umem.address ...
2019-09-19Merge tag 'dma-mapping-5.4' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds1-1/+4
Pull dma-mapping updates from Christoph Hellwig: - add dma-mapping and block layer helpers to take care of IOMMU merging for mmc plus subsequent fixups (Yoshihiro Shimoda) - rework handling of the pgprot bits for remapping (me) - take care of the dma direct infrastructure for swiotlb-xen (me) - improve the dma noncoherent remapping infrastructure (me) - better defaults for ->mmap, ->get_sgtable and ->get_required_mask (me) - cleanup mmaping of coherent DMA allocations (me) - various misc cleanups (Andy Shevchenko, me) * tag 'dma-mapping-5.4' of git://git.infradead.org/users/hch/dma-mapping: (41 commits) mmc: renesas_sdhi_internal_dmac: Add MMC_CAP2_MERGE_CAPABLE mmc: queue: Fix bigger segments usage arm64: use asm-generic/dma-mapping.h swiotlb-xen: merge xen_unmap_single into xen_swiotlb_unmap_page swiotlb-xen: simplify cache maintainance swiotlb-xen: use the same foreign page check everywhere swiotlb-xen: remove xen_swiotlb_dma_mmap and xen_swiotlb_dma_get_sgtable xen: remove the exports for xen_{create,destroy}_contiguous_region xen/arm: remove xen_dma_ops xen/arm: simplify dma_cache_maint xen/arm: use dev_is_dma_coherent xen/arm: consolidate page-coherent.h xen/arm: use dma-noncoherent.h calls for xen-swiotlb cache maintainance arm: remove wrappers for the generic dma remap helpers dma-mapping: introduce a dma_common_find_pages helper dma-mapping: always use VM_DMA_COHERENT for generic DMA remap vmalloc: lift the arm flag for coherent mappings to common code dma-mapping: provide a better default ->get_required_mask dma-mapping: remove the dma_declare_coherent_memory export remoteproc: don't allow modular build ...
2019-09-19Merge branch 'work.mount2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds1-137/+248
Pull misc mount API conversions from Al Viro: "Conversions to new API for shmem and friends and for mount_mtd()-using filesystems. As for the rest of the mount API conversions in -next, some of them belong in the individual trees (e.g. binderfs one should definitely go through android folks, after getting redone on top of their changes). I'm going to drop those and send the rest (trivial ones + stuff ACKed by maintainers) in a separate series - by that point they are independent from each other. Some stuff has already migrated into individual trees (NFS conversion, for example, or FUSE stuff, etc.); those presumably will go through the regular merges from corresponding trees." * 'work.mount2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: vfs: Make fs_parse() handle fs_param_is_fd-type params better vfs: Convert ramfs, shmem, tmpfs, devtmpfs, rootfs to use the new mount API shmem_parse_one(): switch to use of fs_parse() shmem_parse_options(): take handling a single option into a helper shmem_parse_options(): don't bother with mpol in separate variable shmem_parse_options(): use a separate structure to keep the results make shmem_fill_super() static make ramfs_fill_super() static devtmpfs: don't mix {ramfs,shmem}_fill_super() with mount_single() vfs: Convert squashfs to use the new mount API mtd: Kill mount_mtd() vfs: Convert jffs2 to use the new mount API vfs: Convert cramfs to use the new mount API vfs: Convert romfs to use the new mount API vfs: Add a single-or-reconfig keying to vfs_get_super()
2019-09-18Merge tag 'xfs-5.4-merge-7' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds2-8/+18
Pull xfs updates from Darrick Wong: "For this cycle we have the usual pile of cleanups and bug fixes, some performance improvements for online metadata scrubbing, massive speedups in the directory entry creation code, some performance improvement in the file ACL lookup code, a fix for a logging stall during mount, and fixes for concurrency problems. It has survived a couple of weeks of xfstests runs and merges cleanly. Summary: - Remove KM_SLEEP/KM_NOSLEEP. - Ensure that memory buffers for IO are properly sector-aligned to avoid problems that the block layer doesn't check. - Make the bmap scrubber more efficient in its record checking. - Don't crash xfs_db when superblock inode geometry is corrupt. - Fix btree key helper functions. - Remove unneeded error returns for things that can't fail. - Fix buffer logging bugs in repair. - Clean up iterator return values. - Speed up directory entry creation. - Enable allocation of xattr value memory buffer during lookup. - Fix readahead racing with truncate/punch hole. - Other minor cleanups. - Fix one AGI/AGF deadlock with RENAME_WHITEOUT. - More BUG -> WARN whackamole. - Fix various problems with the log failing to advance under certain circumstances, which results in stalls during mount" * tag 'xfs-5.4-merge-7' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (45 commits) xfs: push the grant head when the log head moves forward xfs: push iclog state cleaning into xlog_state_clean_log xfs: factor iclog state processing out of xlog_state_do_callback() xfs: factor callbacks out of xlog_state_do_callback() xfs: factor debug code out of xlog_state_do_callback() xfs: prevent CIL push holdoff in log recovery xfs: fix missed wakeup on l_flush_wait xfs: push the AIL in xlog_grant_head_wake xfs: Use WARN_ON_ONCE for bailout mount-operation xfs: Fix deadlock between AGI and AGF with RENAME_WHITEOUT xfs: define a flags field for the AG geometry ioctl structure xfs: add a xfs_valid_startblock helper xfs: remove the unused XFS_ALLOC_USERDATA flag xfs: cleanup xfs_fsb_to_db xfs: fix the dax supported check in xfs_ioctl_setattr_dax_invalidate xfs: Fix stale data exposure when readahead races with hole punch fs: Export generic_fadvise() mm: Handle MADV_WILLNEED through vfs_fadvise() xfs: allocate xattr buffer on demand xfs: consolidate attribute value copying ...
2019-09-18Merge tag 'vfs-5.4-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds4-18/+38
Pull swap access updates from Darrick Wong: "Prohibit writing to active swap files and swap partitions. There's no non-malicious use case for allowing userspace to scribble on storage that the kernel thinks it owns" * tag 'vfs-5.4-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: vfs: don't allow writes to swap files mm: set S_SWAPFILE on blockdev swap devices
2019-09-17Merge tag 'for-5.4/block-2019-09-16' of git://git.kernel.dk/linux-blockLinus Torvalds3-20/+243
Pull block updates from Jens Axboe: - Two NVMe pull requests: - ana log parse fix from Anton - nvme quirks support for Apple devices from Ben - fix missing bio completion tracing for multipath stack devices from Hannes and Mikhail - IP TOS settings for nvme rdma and tcp transports from Israel - rq_dma_dir cleanups from Israel - tracing for Get LBA Status command from Minwoo - Some nvme-tcp cleanups from Minwoo, Potnuri and Myself - Some consolidation between the fabrics transports for handling the CAP register - reset race with ns scanning fix for fabrics (move fabrics commands to a dedicated request queue with a different lifetime from the admin request queue)." - controller reset and namespace scan races fixes - nvme discovery log change uevent support - naming improvements from Keith - multiple discovery controllers reject fix from James - some regular cleanups from various people - Series fixing (and re-fixing) null_blk debug printing and nr_devices checks (André) - A few pull requests from Song, with fixes from Andy, Guoqing, Guilherme, Neil, Nigel, and Yufen. - REQ_OP_ZONE_RESET_ALL support (Chaitanya) - Bio merge handling unification (Christoph) - Pick default elevator correctly for devices with special needs (Damien) - Block stats fixes (Hou) - Timeout and support devices nbd fixes (Mike) - Series fixing races around elevator switching and device add/remove (Ming) - sed-opal cleanups (Revanth) - Per device weight support for BFQ (Fam) - Support for blk-iocost, a new model that can properly account cost of IO workloads. (Tejun) - blk-cgroup writeback fixes (Tejun) - paride queue init fixes (zhengbin) - blk_set_runtime_active() cleanup (Stanley) - Block segment mapping optimizations (Bart) - lightnvm fixes (Hans/Minwoo/YueHaibing) - Various little fixes and cleanups * tag 'for-5.4/block-2019-09-16' of git://git.kernel.dk/linux-block: (186 commits) null_blk: format pr_* logs with pr_fmt null_blk: match the type of parameter nr_devices null_blk: do not fail the module load with zero devices block: also check RQF_STATS in blk_mq_need_time_stamp() block: make rq sector size accessible for block stats bfq: Fix bfq linkage error raid5: use bio_end_sector in r5_next_bio raid5: remove STRIPE_OPS_REQ_PENDING md: add feature flag MD_FEATURE_RAID0_LAYOUT md/raid0: avoid RAID0 data corruption due to layout confusion. raid5: don't set STRIPE_HANDLE to stripe which is in batch list raid5: don't increment read_errors on EILSEQ return nvmet: fix a wrong error status returned in error log page nvme: send discovery log page change events to userspace nvme: add uevent variables for controller devices nvme: enable aen regardless of the presence of I/O queues nvme-fabrics: allow discovery subsystems accept a kato nvmet: Use PTR_ERR_OR_ZERO() in nvmet_init_discovery() nvme: Remove redundant assignment of cq vector nvme: Assign subsys instance from first ctrl ...
2019-09-17Merge branch 'for-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpuLinus Torvalds1-14/+9
Pull percpu updates from Dennis Zhou: "A couple of updates to clean up the code with no change in behavior" * 'for-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu: percpu: Use struct_size() helper percpu: fix typo in pcpu_setup_first_chunk() comment percpu: Make pcpu_setup_first_chunk() void function
2019-09-16Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds2-2/+2
Pull scheduler updates from Ingo Molnar: - MAINTAINERS: Add Mark Rutland as perf submaintainer, Juri Lelli and Vincent Guittot as scheduler submaintainers. Add Dietmar Eggemann, Steven Rostedt, Ben Segall and Mel Gorman as scheduler reviewers. As perf and the scheduler is getting bigger and more complex, document the status quo of current responsibilities and interests, and spread the review pain^H^H^H^H fun via an increase in the Cc: linecount generated by scripts/get_maintainer.pl. :-) - Add another series of patches that brings the -rt (PREEMPT_RT) tree closer to mainline: split the monolithic CONFIG_PREEMPT dependencies into a new CONFIG_PREEMPTION category that will allow the eventual introduction of CONFIG_PREEMPT_RT. Still a few more hundred patches to go though. - Extend the CPU cgroup controller with uclamp.min and uclamp.max to allow the finer shaping of CPU bandwidth usage. - Micro-optimize energy-aware wake-ups from O(CPUS^2) to O(CPUS). - Improve the behavior of high CPU count, high thread count applications running under cpu.cfs_quota_us constraints. - Improve balancing with SCHED_IDLE (SCHED_BATCH) tasks present. - Improve CPU isolation housekeeping CPU allocation NUMA locality. - Fix deadline scheduler bandwidth calculations and logic when cpusets rebuilds the topology, or when it gets deadline-throttled while it's being offlined. - Convert the cpuset_mutex to percpu_rwsem, to allow it to be used from setscheduler() system calls without creating global serialization. Add new synchronization between cpuset topology-changing events and the deadline acceptance tests in setscheduler(), which were broken before. - Rework the active_mm state machine to be less confusing and more optimal. - Rework (simplify) the pick_next_task() slowpath. - Improve load-balancing on AMD EPYC systems. - ... and misc cleanups, smaller fixes and improvements - please see the Git log for more details. * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits) sched/psi: Correct overly pessimistic size calculation sched/fair: Speed-up energy-aware wake-ups sched/uclamp: Always use 'enum uclamp_id' for clamp_id values sched/uclamp: Update CPU's refcount on TG's clamp changes sched/uclamp: Use TG's clamps to restrict TASK's clamps sched/uclamp: Propagate system defaults to the root group sched/uclamp: Propagate parent clamps sched/uclamp: Extend CPU's cgroup controller sched/topology: Improve load balancing on AMD EPYC systems arch, ia64: Make NUMA select SMP sched, perf: MAINTAINERS update, add submaintainers and reviewers sched/fair: Use rq_lock/unlock in online_fair_sched_group cpufreq: schedutil: fix equation in comment sched: Rework pick_next_task() slow-path sched: Allow put_prev_task() to drop rq->lock sched/fair: Expose newidle_balance() sched: Add task_struct pointer to sched_class::set_curr_task sched: Rework CPU hotplug task selection sched/{rt,deadline}: Fix set_next_task vs pick_next_task sched: Fix kerneldoc comment for ia64_set_curr_task ...
2019-09-16Merge branch 'sched/rt' into sched/core, to pick up -rt changesIngo Molnar2-28/+50
Pick up the first couple of patches working towards PREEMPT_RT. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-09-12vfs: Convert ramfs, shmem, tmpfs, devtmpfs, rootfs to use the new mount APIDavid Howells1-79/+108
Convert the ramfs, shmem, tmpfs, devtmpfs and rootfs filesystems to the new internal mount API as the old one will be obsoleted and removed. This allows greater flexibility in communication of mount parameters between userspace, the VFS and the filesystem. See Documentation/filesystems/mount_api.txt for more information. Note that tmpfs is slightly tricky as it can contain embedded commas, so it can't be trivially split up using strsep() to break on commas in generic_parse_monolithic(). Instead, tmpfs has to supply its own generic parser. However, if tmpfs changes, then devtmpfs and rootfs, which are wrappers around tmpfs or ramfs, must change too - and thus so must ramfs, so these had to be converted also. [AV: rewritten] Signed-off-by: David Howells <dhowells@redhat.com> cc: Hugh Dickins <hughd@google.com> cc: linux-mm@kvack.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-09-12shmem_parse_one(): switch to use of fs_parse()Al Viro1-67/+116
This thing will eventually become our ->parse_param(), while shmem_parse_options() - ->parse_monolithic(). At that point shmem_parse_options() will start calling vfs_parse_fs_string(), rather than calling shmem_parse_one() directly. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-09-12shmem_parse_options(): take handling a single option into a helperAl Viro1-69/+79
mechanical move. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-09-12shmem_parse_options(): don't bother with mpol in separate variableAl Viro1-6/+5
just use ctx->mpol (note that callers always set ctx->mpol to NULL when calling that). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-09-12shmem_parse_options(): use a separate structure to keep the resultsAl Viro1-43/+67
... and copy the data from it into sbinfo in the callers. For use by remount we need to keep track whether there'd been options setting max_inodes, max_blocks and huge resp. and do the sanity checks (and copying) only if such options had been seen. uid/gid/mode is ignored by remount and NULL mpol is already explicitly treated as "ignore it", so we don't need to keep track of those. Note: theoretically, mpol_parse_string() may return NULL not in case of error (for default policy), so the assumption that NULL mpol means "change nothing" is incorrect. However, that's the mainline behaviour and any changes belong in a separate patch. If we go for that, we'll need to keep track of having encountered mpol= option too. [changes in remount logics from Hugh Dickins folded] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-09-07mm, notifier: Catch sleeping/blocking for !blockableDaniel Vetter1-2/+13
We need to make sure implementations don't cheat and don't have a possible schedule/blocking point deeply burried where review can't catch it. I'm not sure whether this is the best way to make sure all the might_sleep() callsites trigger, and it's a bit ugly in the code flow. But it gets the job done. Inspired by an i915 patch series which did exactly that, because the rules haven't been entirely clear to us. Link: https://lore.kernel.org/r/20190826201425.17547-5-daniel.vetter@ffwll.ch Reviewed-by: Christian König <christian.koenig@amd.com> (v1) Reviewed-by: Jérôme Glisse <jglisse@redhat.com> (v4) Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-09-07pagewalk: use lockdep_assert_held for locking validationChristoph Hellwig1-2/+2
Use lockdep to check for held locks instead of using home grown asserts. Link: https://lore.kernel.org/r/20190828141955.22210-4-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com> Reviewed-by: Steven Price <steven.price@arm.com> Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-09-07pagewalk: separate function pointers from iterator dataChristoph Hellwig8-148/+140
The mm_walk structure currently mixed data and code. Split out the operations vectors into a new mm_walk_ops structure, and while we are changing the API also declare the mm_walk structure inside the walk_page_range and walk_page_vma functions. Based on patch from Linus Torvalds. Link: https://lore.kernel.org/r/20190828141955.22210-3-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com> Reviewed-by: Steven Price <steven.price@arm.com> Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-09-07mm: split out a new pagewalk.h header from mm.hChristoph Hellwig8-6/+8
Add a new header for the two handful of users of the walk_page_range / walk_page_vma interface instead of polluting all users of mm.h with it. Link: https://lore.kernel.org/r/20190828141955.22210-2-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com> Reviewed-by: Steven Price <steven.price@arm.com> Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-09-07mm/mmu_notifiers: prime lockdepDaniel Vetter1-0/+7
We want to teach lockdep that mmu notifiers can be called from direct reclaim paths, since on many CI systems load might never reach that level (e.g. when just running fuzzer or small functional tests). I've put the annotation into mmu_notifier_register since only when we have mmu notifiers registered is there any point in teaching lockdep about them. Also, we already have a kmalloc(, GFP_KERNEL), so this is safe. Link: https://lore.kernel.org/r/20190826201425.17547-3-daniel.vetter@ffwll.ch Suggested-by: Jason Gunthorpe <jgg@mellanox.com> Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-09-07mm/mmu_notifiers: add a lockdep map for invalidate_range_start/endDaniel Vetter1-0/+8
This is a similar idea to the fs_reclaim fake lockdep lock. It's fairly easy to provoke a specific notifier to be run on a specific range: Just prep it, and then munmap() it. A bit harder, but still doable, is to provoke the mmu notifiers for all the various callchains that might lead to them. But both at the same time is really hard to reliably hit, especially when you want to exercise paths like direct reclaim or compaction, where it's not easy to control what exactly will be unmapped. By introducing a lockdep map to tie them all together we allow lockdep to see a lot more dependencies, without having to actually hit them in a single challchain while testing. On Jason's suggestion this is is rolled out for both invalidate_range_start and invalidate_range_end. They both have the same calling context, hence we can share the same lockdep map. Note that the annotation for invalidate_ranage_start is outside of the mm_has_notifiers(), to make sure lockdep is informed about all paths leading to this context irrespective of whether mmu notifiers are present for a given context. We don't do that on the invalidate_range_end side to avoid paying the overhead twice, there the lockdep annotation is pushed down behind the mm_has_notifiers() check. Link: https://lore.kernel.org/r/20190826201425.17547-2-daniel.vetter@ffwll.ch Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-09-05make shmem_fill_super() staticAl Viro1-2/+2
... have callers use shmem_mount() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-09-04percpu: Use struct_size() helperGustavo A. R. Silva1-1/+1
One of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example: struct pcpu_alloc_info { ... struct pcpu_group_info groups[]; }; Make use of the struct_size() helper instead of an open-coded version in order to avoid any potential type mistakes. So, replace the following form: sizeof(*ai) + nr_groups * sizeof(ai->groups[0]) with: struct_size(ai, groups, nr_groups) This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Dennis Zhou <dennis@kernel.org>
2019-09-04mm/balloon_compaction: suppress allocation warningsNadav Amit1-1/+2
There is no reason to print warnings when balloon page allocation fails, as they are expected and can be handled gracefully. Since VMware balloon now uses balloon-compaction infrastructure, and suppressed these warnings before, it is also beneficial to suppress these warnings to keep the same behavior that the balloon had before. Cc: Jason Wang <jasowang@redhat.com> Signed-off-by: Nadav Amit <namit@vmware.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: David Hildenbrand <david@redhat.com>
2019-09-04vmalloc: lift the arm flag for coherent mappings to common codeChristoph Hellwig1-1/+4
The arm architecture had a VM_ARM_DMA_CONSISTENT flag to mark DMA coherent remapping for a while. Lift this flag to common code so that we can use it generically. We also check it in the only place VM_USERMAP is directly check so that we can entirely replace that flag as well (although I'm not even sure why we'd want to allow remapping DMA appings, but I'd rather not change behavior). Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-09-03sched/topology: Improve load balancing on AMD EPYC systemsMatt Fleming2-2/+2
SD_BALANCE_{FORK,EXEC} and SD_WAKE_AFFINE are stripped in sd_init() for any sched domains with a NUMA distance greater than 2 hops (RECLAIM_DISTANCE). The idea being that it's expensive to balance across domains that far apart. However, as is rather unfortunately explained in: commit 32e45ff43eaf ("mm: increase RECLAIM_DISTANCE to 30") the value for RECLAIM_DISTANCE is based on node distance tables from 2011-era hardware. Current AMD EPYC machines have the following NUMA node distances: node distances: node 0 1 2 3 4 5 6 7 0: 10 16 16 16 32 32 32 32 1: 16 10 16 16 32 32 32 32 2: 16 16 10 16 32 32 32 32 3: 16 16 16 10 32 32 32 32 4: 32 32 32 32 10 16 16 16 5: 32 32 32 32 16 10 16 16 6: 32 32 32 32 16 16 10 16 7: 32 32 32 32 16 16 16 10 where 2 hops is 32. The result is that the scheduler fails to load balance properly across NUMA nodes on different sockets -- 2 hops apart. For example, pinning 16 busy threads to NUMA nodes 0 (CPUs 0-7) and 4 (CPUs 32-39) like so, $ numactl -C 0-7,32-39 ./spinner 16 causes all threads to fork and remain on node 0 until the active balancer kicks in after a few seconds and forcibly moves some threads to node 4. Override node_reclaim_distance for AMD Zen. Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Mel Gorman <mgorman@techsingularity.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@surriel.com> Cc: Suravee.Suthikulpanit@amd.com Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas.Lendacky@amd.com Cc: Tony Luck <tony.luck@intel.com> Link: https://lkml.kernel.org/r/20190808195301.13222-3-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-08-30fs: Export generic_fadvise()Jan Kara1-2/+2
Filesystems will need to call this function from their fadvise handlers. CC: stable@vger.kernel.org Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-08-30mm: Handle MADV_WILLNEED through vfs_fadvise()Jan Kara1-6/+16
Currently handling of MADV_WILLNEED hint calls directly into readahead code. Handle it by calling vfs_fadvise() instead so that filesystem can use its ->fadvise() callback to acquire necessary locks or otherwise prepare for the request. Suggested-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Boaz Harrosh <boazh@netapp.com> CC: stable@vger.kernel.org Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-08-30mm: memcontrol: fix percpu vmstats and vmevents flushShakeel Butt1-5/+5
Instead of using raw_cpu_read() use per_cpu() to read the actual data of the corresponding cpu otherwise we will be reading the data of the current cpu for the number of online CPUs. Link: http://lkml.kernel.org/r/20190829203110.129263-1-shakeelb@google.com Fixes: bb65f89b7d3d ("mm: memcontrol: flush percpu vmevents before releasing memcg") Fixes: c350a99ea2b1 ("mm: memcontrol: flush percpu vmstats before releasing memcg") Signed-off-by: Shakeel Butt <shakeelb@google.com> Acked-by: Roman Gushchin <guro@fb.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-08-30mm, memcg: do not set reclaim_state on soft limit reclaimMichal Hocko1-2/+3
Adric Blake has noticed[1] the following warning: WARNING: CPU: 7 PID: 175 at mm/vmscan.c:245 set_task_reclaim_state+0x1e/0x40 [...] Call Trace: mem_cgroup_shrink_node+0x9b/0x1d0 mem_cgroup_soft_limit_reclaim+0x10c/0x3a0 balance_pgdat+0x276/0x540 kswapd+0x200/0x3f0 ? wait_woken+0x80/0x80 kthread+0xfd/0x130 ? balance_pgdat+0x540/0x540 ? kthread_park+0x80/0x80 ret_from_fork+0x35/0x40 ---[ end trace 727343df67b2398a ]--- which tells us that soft limit reclaim is about to overwrite the reclaim_state configured up in the call chain (kswapd in this case but the direct reclaim is equally possible). This means that reclaim stats would get misleading once the soft reclaim returns and another reclaim is done. Fix the warning by dropping set_task_reclaim_state from the soft reclaim which is always called with reclaim_state set up. [1] http://lkml.kernel.org/r/CAE1jjeePxYPvw1mw2B3v803xHVR_BNnz0hQUY_JDMN8ny29M6w@mail.gmail.com Link: http://lkml.kernel.org/r/20190828071808.20410-1-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Reported-by: Adric Blake <promarbler14@gmail.com> Acked-by: Yafang Shao <laoar.shao@gmail.com> Acked-by: Yang Shi <yang.shi@linux.alibaba.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Hillf Danton <hdanton@sina.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-08-30mm/z3fold.c: fix lock/unlock imbalance in z3fold_page_isolateGustavo A. R. Silva1-0/+1
Fix lock/unlock imbalance by unlocking *zhdr* before return. Addresses Coverity ID 1452811 ("Missing unlock") Link: http://lkml.kernel.org/r/20190826030634.GA4379@embeddedor Fixes: d776aaa9895e ("mm/z3fold.c: fix race between migration and destruction") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Henry Burns <henrywolfeburns@gmail.com> Cc: Vitaly Wool <vitalywool@gmail.com> Cc: Shakeel Butt <shakeelb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-08-30mm, memcg: partially revert "mm/memcontrol.c: keep local VM counters in sync with the hierarchical ones"Roman Gushchin1-5/+3
Commit 766a4c19d880 ("mm/memcontrol.c: keep local VM counters in sync with the hierarchical ones") effectively decreased the precision of per-memcg vmstats_local and per-memcg-per-node lruvec percpu counters. That's good for displaying in memory.stat, but brings a serious regression into the reclaim process. One issue I've discovered and debugged is the following: lruvec_lru_size() can return 0 instead of the actual number of pages in the lru list, preventing the kernel to reclaim last remaining pages. Result is yet another dying memory cgroups flooding. The opposite is also happening: scanning an empty lru list is the waste of cpu time. Also, inactive_list_is_low() can return incorrect values, preventing the active lru from being scanned and freed. It can fail both because the size of active and inactive lists are inaccurate, and because the number of workingset refaults isn't precise. In other words, the result is pretty random. I'm not sure, if using the approximate number of slab pages in count_shadow_number() is acceptable, but issues described above are enough to partially revert the patch. Let's keep per-memcg vmstat_local batched (they are only used for displaying stats to the userspace), but keep lruvec stats precise. This change fixes the dead memcg flooding on my setup. Link: http://lkml.kernel.org/r/20190817004726.2530670-1-guro@fb.com Fixes: 766a4c19d880 ("mm/memcontrol.c: keep local VM counters in sync with the hierarchical ones") Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Yafang Shao <laoar.shao@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-08-30mm/zsmalloc.c: fix build when CONFIG_COMPACTION=nAndrew Morton1-0/+2
Fixes: 701d678599d0c1 ("mm/zsmalloc.c: fix race condition in zs_destroy_pool") Link: http://lkml.kernel.org/r/201908251039.5oSbEEUT%25lkp@intel.com Reported-by: kbuild test robot <lkp@intel.com> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Henry Burns <henrywolfeburns@gmail.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Shakeel Butt <shakeelb@google.com> Cc: Jonathan Adams <jwadams@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-08-30mm: memcontrol: flush percpu slab vmstats on kmem offliningRoman Gushchin1-8/+27
I've noticed that the "slab" value in memory.stat is sometimes 0, even if some children memory cgroups have a non-zero "slab" value. The following investigation showed that this is the result of the kmem_cache reparenting in combination with the per-cpu batching of slab vmstats. At the offlining some vmstat value may leave in the percpu cache, not being propagated upwards by the cgroup hierarchy. It means that stats on ancestor levels are lower than actual. Later when slab pages are released, the precise number of pages is substracted on the parent level, making the value negative. We don't show negative values, 0 is printed instead. To fix this issue, let's flush percpu slab memcg and lruvec stats on memcg offlining. This guarantees that numbers on all ancestor levels are accurate and match the actual number of outstanding slab pages. Link: http://lkml.kernel.org/r/20190819202338.363363-3-guro@fb.com Fixes: fb2f2b0adb98 ("mm: memcg/slab: reparent memcg kmem_caches on cgroup removal") Signed-off-by: Roman Gushchin <guro@fb.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.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>
2019-08-30writeback: add tracepoints for cgroup foreign writebacksTejun Heo1-0/+5
cgroup foreign inode handling has quite a bit of heuristics and internal states which sometimes makes it difficult to understand what's going on. Add tracepoints to improve visibility. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-08-28mm/mmu_notifiers: remove the __mmu_notifier_invalidate_range_start/end exportsChristoph Hellwig1-3/+0
No modular code uses these, which makes a lot of sense given the wrappers around them are only called by core mm code. Link: https://lore.kernel.org/r/20190828142109.29012-1-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-08-27mm/hmm: hmm_range_fault() infinite loopRalph Campbell1-0/+3
Normally, callers to handle_mm_fault() are supposed to check the vma->vm_flags first. hmm_range_fault() checks for VM_READ but doesn't check for VM_WRITE if the caller requests a page to be faulted in with write permission (via the hmm_range.pfns[] value). If the vma is write protected, this can result in an infinite loop: hmm_range_fault() walk_page_range() ... hmm_vma_walk_hole() hmm_vma_walk_hole_() hmm_vma_do_fault() handle_mm_fault(FAULT_FLAG_WRITE) /* returns VM_FAULT_WRITE */ /* returns -EBUSY */ /* returns -EBUSY */ /* returns -EBUSY */ /* loops on -EBUSY and range->valid */ Prevent this by checking for vma->vm_flags & VM_WRITE before calling handle_mm_fault(). Link: https://lore.kernel.org/r/20190823221753.2514-3-rcampbell@nvidia.com Signed-off-by: Ralph Campbell <rcampbell@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-08-27mm/hmm: hmm_range_fault() NULL pointer bugRalph Campbell1-4/+9
Although hmm_range_fault() calls find_vma() to make sure that a vma exists before calling walk_page_range(), hmm_vma_walk_hole() can still be called with walk->vma == NULL if the start and end address are not contained within the vma range. hmm_range_fault() /* calls find_vma() but no range check */ walk_page_range() /* calls find_vma(), sets walk->vma = NULL */ __walk_page_range() walk_pgd_range() walk_p4d_range() walk_pud_range() hmm_vma_walk_hole() hmm_vma_walk_hole_() hmm_vma_do_fault() handle_mm_fault(vma=0) Link: https://lore.kernel.org/r/20190823221753.2514-2-rcampbell@nvidia.com Signed-off-by: Ralph Campbell <rcampbell@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-08-27writeback, memcg: Implement foreign dirty flushingTejun Heo2-0/+138
There's an inherent mismatch between memcg and writeback. The former trackes ownership per-page while the latter per-inode. This was a deliberate design decision because honoring per-page ownership in the writeback path is complicated, may lead to higher CPU and IO overheads and deemed unnecessary given that write-sharing an inode across different cgroups isn't a common use-case. Combined with inode majority-writer ownership switching, this works well enough in most cases but there are some pathological cases. For example, let's say there are two cgroups A and B which keep writing to different but confined parts of the same inode. B owns the inode and A's memory is limited far below B's. A's dirty ratio can rise enough to trigger balance_dirty_pages() sleeps but B's can be low enough to avoid triggering background writeback. A will be slowed down without a way to make writeback of the dirty pages happen. This patch implements foreign dirty recording and foreign mechanism so that when a memcg encounters a condition as above it can trigger flushes on bdi_writebacks which can clean its pages. Please see the comment on top of mem_cgroup_track_foreign_dirty_slowpath() for details. A reproducer follows. write-range.c:: #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <fcntl.h> #include <sys/types.h> static const char *usage = "write-range FILE START SIZE\n"; int main(int argc, char **argv) { int fd; unsigned long start, size, end, pos; char *endp; char buf[4096]; if (argc < 4) { fprintf(stderr, usage); return 1; } fd = open(argv[1], O_WRONLY); if (fd < 0) { perror("open"); return 1; } start = strtoul(argv[2], &endp, 0); if (*endp != '\0') { fprintf(stderr, usage); return 1; } size = strtoul(argv[3], &endp, 0); if (*endp != '\0') { fprintf(stderr, usage); return 1; } end = start + size; while (1) { for (pos = start; pos < end; ) { long bread, bwritten = 0; if (lseek(fd, pos, SEEK_SET) < 0) { perror("lseek"); return 1; } bread = read(0, buf, sizeof(buf) < end - pos ? sizeof(buf) : end - pos); if (bread < 0) { perror("read"); return 1; } if (bread == 0) return 0; while (bwritten < bread) { long this; this = write(fd, buf + bwritten, bread - bwritten); if (this < 0) { perror("write"); return 1; } bwritten += this; pos += bwritten; } } } } repro.sh:: #!/bin/bash set -e set -x sysctl -w vm.dirty_expire_centisecs=300000 sysctl -w vm.dirty_writeback_centisecs=300000 sysctl -w vm.dirtytime_expire_seconds=300000 echo 3 > /proc/sys/vm/drop_caches TEST=/sys/fs/cgroup/test A=$TEST/A B=$TEST/B mkdir -p $A $B echo "+memory +io" > $TEST/cgroup.subtree_control echo $((1<<30)) > $A/memory.high echo $((32<<30)) > $B/memory.high rm -f testfile touch testfile fallocate -l 4G testfile echo "Starting B" (echo $BASHPID > $B/cgroup.procs pv -q --rate-limit 70M < /dev/urandom | ./write-range testfile $((2<<30)) $((2<<30))) & echo "Waiting 10s to ensure B claims the testfile inode" sleep 5 sync sleep 5 sync echo "Starting A" (echo $BASHPID > $A/cgroup.procs pv < /dev/urandom | ./write-range testfile 0 $((2<<30))) v2: Added comments explaining why the specific intervals are being used. v3: Use 0 @nr when calling cgroup_writeback_by_id() to use best-effort flushing while avoding possible livelocks. v4: Use get_jiffies_64() and time_before/after64() instead of raw jiffies_64 and arthimetic comparisons as suggested by Jan. Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-08-27writeback: Separate out wb_get_lookup() from wb_get_create()Tejun Heo1-18/+37
Separate out wb_get_lookup() which doesn't try to create one if there isn't already one from wb_get_create(). This will be used by later patches. Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-08-27bdi: Add bdi->idTejun Heo1-2/+63
There currently is no way to universally identify and lookup a bdi without holding a reference and pointer to it. This patch adds an non-recycling bdi->id and implements bdi_get_by_id() which looks up bdis by their ids. This will be used by memcg foreign inode flushing. I left bdi_list alone for simplicity and because while rb_tree does support rcu assignment it doesn't seem to guarantee lossless walk when walk is racing aginst tree rebalance operations. Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-08-24mm/kasan: fix false positive invalid-free reports with CONFIG_KASAN_SW_TAGS=yAndrey Ryabinin1-2/+8
The code like this: ptr = kmalloc(size, GFP_KERNEL); page = virt_to_page(ptr); offset = offset_in_page(ptr); kfree(page_address(page) + offset); may produce false-positive invalid-free reports on the kernel with CONFIG_KASAN_SW_TAGS=y. In the example above we lose the original tag assigned to 'ptr', so kfree() gets the pointer with 0xFF tag. In kfree() we check that 0xFF tag is different from the tag in shadow hence print false report. Instead of just comparing tags, do the following: 1) Check that shadow doesn't contain KASAN_TAG_INVALID. Otherwise it's double-free and it doesn't matter what tag the pointer have. 2) If pointer tag is different from 0xFF, make sure that tag in the shadow is the same as in the pointer. Link: http://lkml.kernel.org/r/20190819172540.19581-1-aryabinin@virtuozzo.com Fixes: 7f94ffbc4c6a ("kasan: add hooks implementation for tag-based mode") Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Reported-by: Walter Wu <walter-zh.wu@mediatek.com> Reported-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Andrey Konovalov <andreyknvl@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-08-24mm/zsmalloc.c: fix race condition in zs_destroy_poolHenry Burns1-2/+59
In zs_destroy_pool() we call flush_work(&pool->free_work). However, we have no guarantee that migration isn't happening in the background at that time. Since migration can't directly free pages, it relies on free_work being scheduled to free the pages. But there's nothing preventing an in-progress migrate from queuing the work *after* zs_unregister_migration() has called flush_work(). Which would mean pages still pointing at the inode when we free it. Since we know at destroy time all objects should be free, no new migrations can come in (since zs_page_isolate() fails for fully-free zspages). This means it is sufficient to track a "# isolated zspages" count by class, and have the destroy logic ensure all such pages have drained before proceeding. Keeping that state under the class spinlock keeps the logic straightforward. In this case a memory leak could lead to an eventual crash if compaction hits the leaked page. This crash would only occur if people are changing their zswap backend at runtime (which eventually starts destruction). Link: http://lkml.kernel.org/r/20190809181751.219326-2-henryburns@google.com Fixes: 48b4800a1c6a ("zsmalloc: page migration support") Signed-off-by: Henry Burns <henryburns@google.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Henry Burns <henrywolfeburns@gmail.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Shakeel Butt <shakeelb@google.com> Cc: Jonathan Adams <jwadams@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-08-24mm/zsmalloc.c: migration can leave pages in ZS_EMPTY indefinitelyHenry Burns1-4/+15
In zs_page_migrate() we call putback_zspage() after we have finished migrating all pages in this zspage. However, the return value is ignored. If a zs_free() races in between zs_page_isolate() and zs_page_migrate(), freeing the last object in the zspage, putback_zspage() will leave the page in ZS_EMPTY for potentially an unbounded amount of time. To fix this, we need to do the same thing as zs_page_putback() does: schedule free_work to occur. To avoid duplicated code, move the sequence to a new putback_zspage_deferred() function which both zs_page_migrate() and zs_page_putback() call. Link: http://lkml.kernel.org/r/20190809181751.219326-1-henryburns@google.com Fixes: 48b4800a1c6a ("zsmalloc: page migration support") Signed-off-by: Henry Burns <henryburns@google.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Henry Burns <henrywolfeburns@gmail.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Shakeel Butt <shakeelb@google.com> Cc: Jonathan Adams <jwadams@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-08-24mm, page_owner: handle THP splits correctlyVlastimil Babka1-0/+4
THP splitting path is missing the split_page_owner() call that split_page() has. As a result, split THP pages are wrongly reported in the page_owner file as order-9 pages. Furthermore when the former head page is freed, the remaining former tail pages are not listed in the page_owner file at all. This patch fixes that by adding the split_page_owner() call into __split_huge_page(). Link: http://lkml.kernel.org/r/20190820131828.22684-2-vbabka@suse.cz Fixes: a9627bc5e34e ("mm/page_owner: introduce split_page_owner and replace manual handling") Reported-by: Kirill A. Shutemov <kirill@shutemov.name> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Cc: Michal Hocko <mhocko@kernel.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Matthew Wilcox <willy@infradead.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-08-24mm: memcontrol: flush percpu vmevents before releasing memcgRoman Gushchin1-1/+21
Similar to vmstats, percpu caching of local vmevents leads to an accumulation of errors on non-leaf levels. This happens because some leftovers may remain in percpu caches, so that they are never propagated up by the cgroup tree and just disappear into nonexistence with on releasing of the memory cgroup. To fix this issue let's accumulate and propagate percpu vmevents values before releasing the memory cgroup similar to what we're doing with vmstats. Since on cpu hotplug we do flush percpu vmstats anyway, we can iterate only over online cpus. Link: http://lkml.kernel.org/r/20190819202338.363363-4-guro@fb.com Fixes: 42a300353577 ("mm: memcontrol: fix recursive statistics correctness & scalabilty") Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-08-24mm: memcontrol: flush percpu vmstats before releasing memcgRoman Gushchin1-0/+40
Percpu caching of local vmstats with the conditional propagation by the cgroup tree leads to an accumulation of errors on non-leaf levels. Let's imagine two nested memory cgroups A and A/B. Say, a process belonging to A/B allocates 100 pagecache pages on the CPU 0. The percpu cache will spill 3 times, so that 32*3=96 pages will be accounted to A/B and A atomic vmstat counters, 4 pages will remain in the percpu cache. Imagine A/B is nearby memory.max, so that every following allocation triggers a direct reclaim on the local CPU. Say, each such attempt will free 16 pages on a new cpu. That means every percpu cache will have -16 pages, except the first one, which will have 4 - 16 = -12. A/B and A atomic counters will not be touched at all. Now a user removes A/B. All percpu caches are freed and corresponding vmstat numbers are forgotten. A has 96 pages more than expected. As memory cgroups are created and destroyed, errors do accumulate. Even 1-2 pages differences can accumulate into large numbers. To fix this issue let's accumulate and propagate percpu vmstat values before releasing the memory cgroup. At this point these numbers are stable and cannot be changed. Since on cpu hotplug we do flush percpu vmstats anyway, we can iterate only over online cpus. Link: http://lkml.kernel.org/r/20190819202338.363363-2-guro@fb.com Fixes: 42a300353577 ("mm: memcontrol: fix recursive statistics correctness & scalabilty") Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-08-24mm, page_alloc: move_freepages should not examine struct page of reserved memoryDavid Rientjes1-15/+4
After commit 907ec5fca3dc ("mm: zero remaining unavailable struct pages"), struct page of reserved memory is zeroed. This causes page->flags to be 0 and fixes issues related to reading /proc/kpageflags, for example, of reserved memory. The VM_BUG_ON() in move_freepages_block(), however, assumes that page_zone() is meaningful even for reserved memory. That assumption is no longer true after the aforementioned commit. There's no reason why move_freepages_block() should be testing the legitimacy of page_zone() for reserved memory; its scope is limited only to pages on the zone's freelist. Note that pfn_valid() can be true for reserved memory: there is a backing struct page. The check for page_to_nid(page) is also buggy but reserved memory normally only appears on node 0 so the zeroing doesn't affect this. Move the debug checks to after verifying PageBuddy is true. This isolates the scope of the checks to only be for buddy pages which are on the zone's freelist which move_freepages_block() is operating on. In this case, an incorrect node or zone is a bug worthy of being warned about (and the examination of struct page is acceptable bcause this memory is not reserved). Why does move_freepages_block() gets called on reserved memory? It's simply math after finding a valid free page from the per-zone free area to use as fallback. We find the beginning and end of the pageblock of the valid page and that can bring us into memory that was reserved per the e820. pfn_valid() is still true (it's backed by a struct page), but since it's zero'd we shouldn't make any inferences here about comparing its node or zone. The current node check just happens to succeed most of the time by luck because reserved memory typically appears on node 0. The fix here is to validate that we actually have buddy pages before testing if there's any type of zone or node strangeness going on. We noticed it almost immediately after bringing 907ec5fca3dc in on CONFIG_DEBUG_VM builds. It depends on finding specific free pages in the per-zone free area where the math in move_freepages() will bring the start or end pfn into reserved memory and wanting to claim that entire pageblock as a new migratetype. So the path will be rare, require CONFIG_DEBUG_VM, and require fallback to a different migratetype. Some struct pages were already zeroed from reserve pages before 907ec5fca3c so it theoretically could trigger before this commit. I think it's rare enough under a config option that most people don't run that others may not have noticed. I wouldn't argue against a stable tag and the backport should be easy enough, but probably wouldn't single out a commit that this is fixing. Mel said: : The overhead of the debugging check is higher with this patch although : it'll only affect debug builds and the path is not particularly hot. : If this was a concern, I think it would be reasonable to simply remove : the debugging check as the zone boundaries are checked in : move_freepages_block and we never expect a zone/node to be smaller than : a pageblock and stuck in the middle of another zone. Link: http://lkml.kernel.org/r/alpine.DEB.2.21.1908122036560.10779@chino.kir.corp.google.com Signed-off-by: David Rientjes <rientjes@google.com> Acked-by: Mel Gorman <mgorman@techsingularity.net> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pavel Tatashin <pavel.tatashin@microsoft.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-08-24mm/z3fold.c: fix race between migration and destructionHenry Burns1-0/+89
In z3fold_destroy_pool() we call destroy_workqueue(&pool->compact_wq). However, we have no guarantee that migration isn't happening in the background at that time. Migration directly calls queue_work_on(pool->compact_wq), if destruction wins that race we are using a destroyed workqueue. Link: http://lkml.kernel.org/r/20190809213828.202833-1-henryburns@google.com Signed-off-by: Henry Burns <henryburns@google.com> Cc: Vitaly Wool <vitalywool@gmail.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Jonathan Adams <jwadams@google.com> Cc: Henry Burns <henrywolfeburns@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-08-23mm/hmm: fix hmm_range_fault()'s handling of swapped out pagesYang, Philip1-0/+3
hmm_range_fault() may return NULL pages because some of the pfns are equal to HMM_PFN_NONE. This happens randomly under memory pressure. The reason is during the swapped out page pte path, hmm_vma_handle_pte() doesn't update the fault variable from cpu_flags, so it failed to call hmm_vam_do_fault() to swap the page in. The fix is to call hmm_pte_need_fault() to update fault variable. Fixes: 74eee180b935 ("mm/hmm/mirror: device page fault handler") Link: https://lore.kernel.org/r/20190815205227.7949-1-Philip.Yang@amd.com Signed-off-by: Philip Yang <Philip.Yang@amd.com> Reviewed-by: "Jérôme Glisse" <jglisse@redhat.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-08-21mm/mmu_notifiers: remove unregister_no_releaseJason Gunthorpe1-31/+0
mmu_notifier_unregister_no_release() and mmu_notifier_call_srcu() no longer have any users, they have all been converted to use mmu_notifier_put(). So delete this difficult to use interface. Link: https://lore.kernel.org/r/20190806231548.25242-12-jgg@ziepe.ca Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ralph Campbell <rcampbell@nvidia.com> Tested-by: Ralph Campbell <rcampbell@nvidia.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>