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2020-01-31Merge tag 'riscv-for-linus-5.6-mw0' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: "This contains a handful of patches for this merge window: - Support for kasan - 32-bit physical addresses on rv32i-based systems - Support for CONFIG_DEBUG_VIRTUAL - DT entry for the FU540 GPIO controller, which has recently had a device driver merged These boot a buildroot-based system on QEMU's virt board for me" * tag 'riscv-for-linus-5.6-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: riscv: dts: Add DT support for SiFive FU540 GPIO driver riscv: mm: add support for CONFIG_DEBUG_VIRTUAL riscv: keep 32-bit kernel to 32-bit phys_addr_t kasan: Add riscv to KASAN documentation. riscv: Add KASAN support kasan: No KASAN's memmove check if archs don't have it.
2020-01-31Merge tag 'kvm-5.6-1' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Paolo Bonzini: "This is the first batch of KVM changes. ARM: - cleanups and corner case fixes. PPC: - Bugfixes x86: - Support for mapping DAX areas with large nested page table entries. - Cleanups and bugfixes here too. A particularly important one is a fix for FPU load when the thread has TIF_NEED_FPU_LOAD. There is also a race condition which could be used in guest userspace to exploit the guest kernel, for which the embargo expired today. - Fast path for IPI delivery vmexits, shaving about 200 clock cycles from IPI latency. - Protect against "Spectre-v1/L1TF" (bring data in the cache via speculative out of bound accesses, use L1TF on the sibling hyperthread to read it), which unfortunately is an even bigger whack-a-mole game than SpectreV1. Sean continues his mission to rewrite KVM. In addition to a sizable number of x86 patches, this time he contributed a pretty large refactoring of vCPU creation that affects all architectures but should not have any visible effect. s390 will come next week together with some more x86 patches" * tag 'kvm-5.6-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (204 commits) x86/KVM: Clean up host's steal time structure x86/KVM: Make sure KVM_VCPU_FLUSH_TLB flag is not missed x86/kvm: Cache gfn to pfn translation x86/kvm: Introduce kvm_(un)map_gfn() x86/kvm: Be careful not to clear KVM_VCPU_FLUSH_TLB bit KVM: PPC: Book3S PR: Fix -Werror=return-type build failure KVM: PPC: Book3S HV: Release lock on page-out failure path KVM: arm64: Treat emulated TVAL TimerValue as a signed 32-bit integer KVM: arm64: pmu: Only handle supported event counters KVM: arm64: pmu: Fix chained SW_INCR counters KVM: arm64: pmu: Don't mark a counter as chained if the odd one is disabled KVM: arm64: pmu: Don't increment SW_INCR if PMCR.E is unset KVM: x86: Use a typedef for fastop functions KVM: X86: Add 'else' to unify fastop and execute call path KVM: x86: inline memslot_valid_for_gpte KVM: x86/mmu: Use huge pages for DAX-backed files KVM: x86/mmu: Remove lpage_is_disallowed() check from set_spte() KVM: x86/mmu: Fold max_mapping_level() into kvm_mmu_hugepage_adjust() KVM: x86/mmu: Zap any compound page when collapsing sptes KVM: x86/mmu: Remove obsolete gfn restoration in FNAME(fetch) ...
2020-01-30Merge branch 'cve-2019-3016' into kvm-next-5.6Paolo Bonzini
From Boris Ostrovsky: The KVM hypervisor may provide a guest with ability to defer remote TLB flush when the remote VCPU is not running. When this feature is used, the TLB flush will happen only when the remote VPCU is scheduled to run again. This will avoid unnecessary (and expensive) IPIs. Under certain circumstances, when a guest initiates such deferred action, the hypervisor may miss the request. It is also possible that the guest may mistakenly assume that it has already marked remote VCPU as needing a flush when in fact that request had already been processed by the hypervisor. In both cases this will result in an invalid translation being present in a vCPU, potentially allowing accesses to memory locations in that guest's address space that should not be accessible. Note that only intra-guest memory is vulnerable. The five patches address both of these problems: 1. The first patch makes sure the hypervisor doesn't accidentally clear a guest's remote flush request 2. The rest of the patches prevent the race between hypervisor acknowledging a remote flush request and guest issuing a new one. Conflicts: arch/x86/kvm/x86.c [move from kvm_arch_vcpu_free to kvm_arch_vcpu_destroy]
2020-01-29Merge tag 'for-linus-hmm' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma Pull mmu_notifier updates from Jason Gunthorpe: "This small series revises the names in mmu_notifier to make the code clearer and more readable" * tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: mm/mmu_notifiers: Use 'interval_sub' as the variable for mmu_interval_notifier mm/mmu_notifiers: Use 'subscription' as the variable name for mmu_notifier mm/mmu_notifier: Rename struct mmu_notifier_mm to mmu_notifier_subscriptions
2020-01-29Merge tag 'for-5.6/io_uring-vfs-2020-01-29' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull io_uring updates from Jens Axboe: - Support for various new opcodes (fallocate, openat, close, statx, fadvise, madvise, openat2, non-vectored read/write, send/recv, and epoll_ctl) - Faster ring quiesce for fileset updates - Optimizations for overflow condition checking - Support for max-sized clamping - Support for probing what opcodes are supported - Support for io-wq backend sharing between "sibling" rings - Support for registering personalities - Lots of little fixes and improvements * tag 'for-5.6/io_uring-vfs-2020-01-29' of git://git.kernel.dk/linux-block: (64 commits) io_uring: add support for epoll_ctl(2) eventpoll: support non-blocking do_epoll_ctl() calls eventpoll: abstract out epoll_ctl() handler io_uring: fix linked command file table usage io_uring: support using a registered personality for commands io_uring: allow registering credentials io_uring: add io-wq workqueue sharing io-wq: allow grabbing existing io-wq io_uring/io-wq: don't use static creds/mm assignments io-wq: make the io_wq ref counted io_uring: fix refcounting with batched allocations at OOM io_uring: add comment for drain_next io_uring: don't attempt to copy iovec for READ/WRITE io_uring: honor IOSQE_ASYNC for linked reqs io_uring: prep req when do IOSQE_ASYNC io_uring: use labeled array init in io_op_defs io_uring: optimise sqe-to-req flags translation io_uring: remove REQ_F_IO_DRAINED io_uring: file switch work needs to get flushed on exit io_uring: hide uring_fd in ctx ...
2020-01-28Merge tag 'for-5.6-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs updates from David Sterba: "Features, highlights: - async discard - "mount -o discard=async" to enable it - freed extents are not discarded immediatelly, but grouped together and trimmed later, with IO rate limiting - the "sync" mode submits short extents that could have been ignored completely by the device, for SATA prior to 3.1 the requests are unqueued and have a big impact on performance - the actual discard IO requests have been moved out of transaction commit to a worker thread, improving commit latency - IO rate and request size can be tuned by sysfs files, for now enabled only with CONFIG_BTRFS_DEBUG as we might need to add/delete the files and don't have a stable-ish ABI for general use, defaults are conservative - export device state info in sysfs, eg. missing, writeable - no discard of extents known to be untouched on disk (eg. after reservation) - device stats reset is logged with process name and PID that called the ioctl Fixes: - fix missing hole after hole punching and fsync when using NO_HOLES - writeback: range cyclic mode could miss some dirty pages and lead to OOM - two more corner cases for metadata_uuid change after power loss during the change - fix infinite loop during fsync after mix of rename operations Core changes: - qgroup assign returns ENOTCONN when quotas not enabled, used to return EINVAL that was confusing - device closing does not need to allocate memory anymore - snapshot aware code got removed, disabled for years due to performance problems, reimplmentation will allow to select wheter defrag breaks or does not break COW on shared extents - tree-checker: - check leaf chunk item size, cross check against number of stripes - verify location keys for DIR_ITEM, DIR_INDEX and XATTR items - new self test for physical -> logical mapping code, used for super block range exclusion - assertion helpers/macros updated to avoid objtool "unreachable code" reports on older compilers or config option combinations" * tag 'for-5.6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (84 commits) btrfs: free block groups after free'ing fs trees btrfs: Fix split-brain handling when changing FSID to metadata uuid btrfs: Handle another split brain scenario with metadata uuid feature btrfs: Factor out metadata_uuid code from find_fsid. btrfs: Call find_fsid from find_fsid_inprogress Btrfs: fix infinite loop during fsync after rename operations btrfs: set trans->drity in btrfs_commit_transaction btrfs: drop log root for dropped roots btrfs: sysfs, add devid/dev_state kobject and device attributes btrfs: Refactor btrfs_rmap_block to improve readability btrfs: Add self-tests for btrfs_rmap_block btrfs: selftests: Add support for dummy devices btrfs: Move and unexport btrfs_rmap_block btrfs: separate definition of assertion failure handlers btrfs: device stats, log when stats are zeroed btrfs: fix improper setting of scanned for range cyclic write cache pages btrfs: safely advance counter when looking up bio csums btrfs: remove unused member btrfs_device::work btrfs: remove unnecessary wrapper get_alloc_profile btrfs: add correction to handle -1 edge case in async discard ...
2020-01-28Merge branch 'x86-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull misc x86 updates from Ingo Molnar: "Misc changes: - Enhance #GP fault printouts by distinguishing between canonical and non-canonical address faults, and also add KASAN fault decoding. - Fix/enhance the x86 NMI handler by putting the duration check into a direct function call instead of an irq_work which we know to be broken in some cases. - Clean up do_general_protection() a bit" * 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/nmi: Remove irq_work from the long duration NMI handler x86/traps: Cleanup do_general_protection() x86/kasan: Print original address on #GP x86/dumpstack: Introduce die_addr() for die() with #GP fault address x86/traps: Print address on #GP x86/insn-eval: Add support for 64-bit kernel mode
2020-01-28Merge branch 'sched-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "These were the main changes in this cycle: - More -rt motivated separation of CONFIG_PREEMPT and CONFIG_PREEMPTION. - Add more low level scheduling topology sanity checks and warnings to filter out nonsensical topologies that break scheduling. - Extend uclamp constraints to influence wakeup CPU placement - Make the RT scheduler more aware of asymmetric topologies and CPU capacities, via uclamp metrics, if CONFIG_UCLAMP_TASK=y - Make idle CPU selection more consistent - Various fixes, smaller cleanups, updates and enhancements - please see the git log for details" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits) sched/fair: Define sched_idle_cpu() only for SMP configurations sched/topology: Assert non-NUMA topology masks don't (partially) overlap idle: fix spelling mistake "iterrupts" -> "interrupts" sched/fair: Remove redundant call to cpufreq_update_util() sched/psi: create /proc/pressure and /proc/pressure/{io|memory|cpu} only when psi enabled sched/fair: Fix sgc->{min,max}_capacity calculation for SD_OVERLAP sched/fair: calculate delta runnable load only when it's needed sched/cputime: move rq parameter in irqtime_account_process_tick stop_machine: Make stop_cpus() static sched/debug: Reset watchdog on all CPUs while processing sysrq-t sched/core: Fix size of rq::uclamp initialization sched/uclamp: Fix a bug in propagating uclamp value in new cgroups sched/fair: Load balance aggressively for SCHED_IDLE CPUs sched/fair : Improve update_sd_pick_busiest for spare capacity case watchdog: Remove soft_lockup_hrtimer_cnt and related code sched/rt: Make RT capacity-aware sched/fair: Make EAS wakeup placement consider uclamp restrictions sched/fair: Make task_fits_capacity() consider uclamp restrictions sched/uclamp: Rename uclamp_util_with() into uclamp_rq_util_with() sched/uclamp: Make uclamp util helpers use and return UL values ...
2020-01-28Merge branch 'efi-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull EFI updates from Ingo Molnar: "The main changes in this cycle were: - Cleanup of the GOP [graphics output] handling code in the EFI stub - Complete refactoring of the mixed mode handling in the x86 EFI stub - Overhaul of the x86 EFI boot/runtime code - Increase robustness for mixed mode code - Add the ability to disable DMA at the root port level in the EFI stub - Get rid of RWX mappings in the EFI memory map and page tables, where possible - Move the support code for the old EFI memory mapping style into its only user, the SGI UV1+ support code. - plus misc fixes, updates, smaller cleanups. ... and due to interactions with the RWX changes, another round of PAT cleanups make a guest appearance via the EFI tree - with no side effects intended" * 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (75 commits) efi/x86: Disable instrumentation in the EFI runtime handling code efi/libstub/x86: Fix EFI server boot failure efi/x86: Disallow efi=old_map in mixed mode x86/boot/compressed: Relax sed symbol type regex for LLVM ld.lld efi/x86: avoid KASAN false positives when accessing the 1: 1 mapping efi: Fix handling of multiple efi_fake_mem= entries efi: Fix efi_memmap_alloc() leaks efi: Add tracking for dynamically allocated memmaps efi: Add a flags parameter to efi_memory_map efi: Fix comment for efi_mem_type() wrt absent physical addresses efi/arm: Defer probe of PCIe backed efifb on DT systems efi/x86: Limit EFI old memory map to SGI UV machines efi/x86: Avoid RWX mappings for all of DRAM efi/x86: Don't map the entire kernel text RW for mixed mode x86/mm: Fix NX bit clearing issue in kernel_map_pages_in_pgd efi/libstub/x86: Fix unused-variable warning efi/libstub/x86: Use mandatory 16-byte stack alignment in mixed mode efi/libstub/x86: Use const attribute for efi_is_64bit() efi: Allow disabling PCI busmastering on bridges during boot efi/x86: Allow translating 64-bit arguments for mixed mode calls ...
2020-01-27Merge tag 'smp-core-2020-01-28' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core SMP updates from Thomas Gleixner: "A small set of SMP core code changes: - Rework the smp function call core code to avoid the allocation of an additional cpumask - Remove the not longer required GFP argument from on_each_cpu_cond() and on_each_cpu_cond_mask() and fixup the callers" * tag 'smp-core-2020-01-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: smp: Remove allocation mask from on_each_cpu_cond.*() smp: Add a smp_cond_func_t argument to smp_call_function_many() smp: Use smp_cond_func_t as type for the conditional function
2020-01-27Merge tag 'timers-core-2020-01-27' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer updates from Thomas Gleixner: "The timekeeping and timers departement provides: - Time namespace support: If a container migrates from one host to another then it expects that clocks based on MONOTONIC and BOOTTIME are not subject to disruption. Due to different boot time and non-suspended runtime these clocks can differ significantly on two hosts, in the worst case time goes backwards which is a violation of the POSIX requirements. The time namespace addresses this problem. It allows to set offsets for clock MONOTONIC and BOOTTIME once after creation and before tasks are associated with the namespace. These offsets are taken into account by timers and timekeeping including the VDSO. Offsets for wall clock based clocks (REALTIME/TAI) are not provided by this mechanism. While in theory possible, the overhead and code complexity would be immense and not justified by the esoteric potential use cases which were discussed at Plumbers '18. The overhead for tasks in the root namespace (ie where host time offsets = 0) is in the noise and great effort was made to ensure that especially in the VDSO. If time namespace is disabled in the kernel configuration the code is compiled out. Kudos to Andrei Vagin and Dmitry Sofanov who implemented this feature and kept on for more than a year addressing review comments, finding better solutions. A pleasant experience. - Overhaul of the alarmtimer device dependency handling to ensure that the init/suspend/resume ordering is correct. - A new clocksource/event driver for Microchip PIT64 - Suspend/resume support for the Hyper-V clocksource - The usual pile of fixes, updates and improvements mostly in the driver code" * tag 'timers-core-2020-01-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (71 commits) alarmtimer: Make alarmtimer_get_rtcdev() a stub when CONFIG_RTC_CLASS=n alarmtimer: Use wakeup source from alarmtimer platform device alarmtimer: Make alarmtimer platform device child of RTC device alarmtimer: Update alarmtimer_get_rtcdev() docs to reflect reality hrtimer: Add missing sparse annotation for __run_timer() lib/vdso: Only read hrtimer_res when needed in __cvdso_clock_getres() MIPS: vdso: Define BUILD_VDSO32 when building a 32bit kernel clocksource/drivers/hyper-v: Set TSC clocksource as default w/ InvariantTSC clocksource/drivers/hyper-v: Untangle stimers and timesync from clocksources clocksource/drivers/timer-microchip-pit64b: Fix sparse warning clocksource/drivers/exynos_mct: Rename Exynos to lowercase clocksource/drivers/timer-ti-dm: Fix uninitialized pointer access clocksource/drivers/timer-ti-dm: Switch to platform_get_irq clocksource/drivers/timer-ti-dm: Convert to devm_platform_ioremap_resource clocksource/drivers/em_sti: Fix variable declaration in em_sti_probe clocksource/drivers/em_sti: Convert to devm_platform_ioremap_resource clocksource/drivers/bcm2835_timer: Fix memory leak of timer clocksource/drivers/cadence-ttc: Use ttc driver as platform driver clocksource/drivers/timer-microchip-pit64b: Add Microchip PIT64B support clocksource/drivers/hyper-v: Reserve PAGE_SIZE space for tsc page ...
2020-01-27Merge branch 'for-5.6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup updates from Tejun Heo: - cgroup2 interface for hugetlb controller. I think this was the last remaining bit which was missing from cgroup2 - fixes for race and a spurious warning in threaded cgroup handling - other minor changes * 'for-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: iocost: Fix iocost_monitor.py due to helper type mismatch cgroup: Prevent double killing of css when enabling threaded cgroup cgroup: fix function name in comment mm: hugetlb controller for cgroups v2
2020-01-27mm: thp: KVM: Explicitly check for THP when populating secondary MMUSean Christopherson
Add a helper, is_transparent_hugepage(), to explicitly check whether a compound page is a THP and use it when populating KVM's secondary MMU. The explicit check fixes a bug where a remapped compound page, e.g. for an XDP Rx socket, is mapped into a KVM guest and is mistaken for a THP, which results in KVM incorrectly creating a huge page in its secondary MMU. Fixes: 936a5fe6e6148 ("thp: kvm mmu transparent hugepage support") Reported-by: syzbot+c9d1fb51ac9d0d10c39d@syzkaller.appspotmail.com Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24smp: Remove allocation mask from on_each_cpu_cond.*()Sebastian Andrzej Siewior
The allocation mask is no longer used by on_each_cpu_cond() and on_each_cpu_cond_mask() and can be removed. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20200117090137.1205765-4-bigeasy@linutronix.de
2020-01-22kasan: No KASAN's memmove check if archs don't have it.Nick Hu
If archs don't have memmove then the C implementation from lib/string.c is used, and then it's instrumented by compiler. So there is no need to add KASAN's memmove to manual checks. Signed-off-by: Nick Hu <nickhu@andestech.com> Acked-by: Dmitry Vyukov <dvyukov@google.com> Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-01-20mm: make do_madvise() available internallyJens Axboe
This is in preparation for enabling this functionality through io_uring. Add a helper that is just exporting what sys_madvise() does, and have the system call use it. No functional changes in this patch. Reviewed-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-01-20bitmap: genericize percpu bitmap region iteratorsDennis Zhou
Bitmaps are fairly popular for their space efficiency, but we don't have generic iterators available. Make percpu's bitmap region iterators available to everyone. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Dennis Zhou <dennis@kernel.org> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2020-01-20Merge tag 'v5.5-rc7' into efi/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-01-14mm/mmu_notifiers: Use 'interval_sub' as the variable for mmu_interval_notifierJason Gunthorpe
The 'interval_sub' is placed on the 'notifier_subscriptions' interval tree. This eliminates the poor name 'mni' for this variable. Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-01-14mm/mmu_notifiers: Use 'subscription' as the variable name for mmu_notifierJason Gunthorpe
The 'subscription' is placed on the 'notifier_subscriptions' list. This eliminates the poor name 'mn' for this variable. Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-01-14mm/mmu_notifier: Rename struct mmu_notifier_mm to mmu_notifier_subscriptionsJason Gunthorpe
The name mmu_notifier_mm implies that the thing is a mm_struct pointer, and is difficult to abbreviate. The struct is actually holding the interval tree and hlist containing the notifiers subscribed to a mm. Use 'subscriptions' as the variable name for this struct instead of the really terrible and misleading 'mmn_mm'. Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-01-14x86/vdso: Handle faults on timens pageDmitry Safonov
If a task belongs to a time namespace then the VVAR page which contains the system wide VDSO data is replaced with a namespace specific page which has the same layout as the VVAR page. Co-developed-by: Andrei Vagin <avagin@gmail.com> Signed-off-by: Andrei Vagin <avagin@gmail.com> Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20191112012724.250792-25-dima@arista.com
2020-01-13mm: memcg/slab: call flush_memcg_workqueue() only if memcg workqueue is validAdrian Huang
When booting with amd_iommu=off, the following WARNING message appears: AMD-Vi: AMD IOMMU disabled on kernel command-line ------------[ cut here ]------------ WARNING: CPU: 0 PID: 0 at kernel/workqueue.c:2772 flush_workqueue+0x42e/0x450 Modules linked in: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.5.0-rc3-amd-iommu #6 Hardware name: Lenovo ThinkSystem SR655-2S/7D2WRCZ000, BIOS D8E101L-1.00 12/05/2019 RIP: 0010:flush_workqueue+0x42e/0x450 Code: ff 0f 0b e9 7a fd ff ff 4d 89 ef e9 33 fe ff ff 0f 0b e9 7f fd ff ff 0f 0b e9 bc fd ff ff 0f 0b e9 a8 fd ff ff e8 52 2c fe ff <0f> 0b 31 d2 48 c7 c6 e0 88 c5 95 48 c7 c7 d8 ad f0 95 e8 19 f5 04 Call Trace: kmem_cache_destroy+0x69/0x260 iommu_go_to_state+0x40c/0x5ab amd_iommu_prepare+0x16/0x2a irq_remapping_prepare+0x36/0x5f enable_IR_x2apic+0x21/0x172 default_setup_apic_routing+0x12/0x6f apic_intr_mode_init+0x1a1/0x1f1 x86_late_time_init+0x17/0x1c start_kernel+0x480/0x53f secondary_startup_64+0xb6/0xc0 ---[ end trace 30894107c3749449 ]--- x2apic: IRQ remapping doesn't support X2APIC mode x2apic disabled The warning is caused by the calling of 'kmem_cache_destroy()' in free_iommu_resources(). Here is the call path: free_iommu_resources kmem_cache_destroy flush_memcg_workqueue flush_workqueue The root cause is that the IOMMU subsystem runs before the workqueue subsystem, which the variable 'wq_online' is still 'false'. This leads to the statement 'if (WARN_ON(!wq_online))' in flush_workqueue() is 'true'. Since the variable 'memcg_kmem_cache_wq' is not allocated during the time, it is unnecessary to call flush_memcg_workqueue(). This prevents the WARNING message triggered by flush_workqueue(). Link: http://lkml.kernel.org/r/20200103085503.1665-1-ahuang12@lenovo.com Fixes: 92ee383f6daab ("mm: fix race between kmem_cache destroy, create and deactivate") Signed-off-by: Adrian Huang <ahuang12@lenovo.com> Reported-by: Xiaochun Lee <lixc17@lenovo.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Cc: Joerg Roedel <jroedel@suse.de> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-13mm/page-writeback.c: improve arithmetic divisionsWen Yang
Use div64_ul() instead of do_div() if the divisor is unsigned long, to avoid truncation to 32-bit on 64-bit platforms. Link: http://lkml.kernel.org/r/20200102081442.8273-4-wenyang@linux.alibaba.com Signed-off-by: Wen Yang <wenyang@linux.alibaba.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Qian Cai <cai@lca.pw> Cc: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-13mm/page-writeback.c: use div64_ul() for u64-by-unsigned-long divideWen Yang
The two variables 'numerator' and 'denominator', though they are declared as long, they should actually be unsigned long (according to the implementation of the fprop_fraction_percpu() function) And do_div() does a 64-by-32 division, while the divisor 'denominator' is unsigned long, thus 64-bit on 64-bit platforms. Hence the proper function to call is div64_ul(). Link: http://lkml.kernel.org/r/20200102081442.8273-3-wenyang@linux.alibaba.com Signed-off-by: Wen Yang <wenyang@linux.alibaba.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Qian Cai <cai@lca.pw> Cc: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-13mm/page-writeback.c: avoid potential division by zero in wb_min_max_ratio()Wen Yang
Patch series "use div64_ul() instead of div_u64() if the divisor is unsigned long". We were first inspired by commit b0ab99e7736a ("sched: Fix possible divide by zero in avg_atom () calculation"), then refer to the recently analyzed mm code, we found this suspicious place. 201 if (min) { 202 min *= this_bw; 203 do_div(min, tot_bw); 204 } And we also disassembled and confirmed it: /usr/src/debug/kernel-4.9.168-016.ali3000/linux-4.9.168-016.ali3000.alios7.x86_64/mm/page-writeback.c: 201 0xffffffff811c37da <__wb_calc_thresh+234>: xor %r10d,%r10d 0xffffffff811c37dd <__wb_calc_thresh+237>: test %rax,%rax 0xffffffff811c37e0 <__wb_calc_thresh+240>: je 0xffffffff811c3800 <__wb_calc_thresh+272> /usr/src/debug/kernel-4.9.168-016.ali3000/linux-4.9.168-016.ali3000.alios7.x86_64/mm/page-writeback.c: 202 0xffffffff811c37e2 <__wb_calc_thresh+242>: imul %r8,%rax /usr/src/debug/kernel-4.9.168-016.ali3000/linux-4.9.168-016.ali3000.alios7.x86_64/mm/page-writeback.c: 203 0xffffffff811c37e6 <__wb_calc_thresh+246>: mov %r9d,%r10d ---> truncates it to 32 bits here 0xffffffff811c37e9 <__wb_calc_thresh+249>: xor %edx,%edx 0xffffffff811c37eb <__wb_calc_thresh+251>: div %r10 0xffffffff811c37ee <__wb_calc_thresh+254>: imul %rbx,%rax 0xffffffff811c37f2 <__wb_calc_thresh+258>: shr $0x2,%rax 0xffffffff811c37f6 <__wb_calc_thresh+262>: mul %rcx 0xffffffff811c37f9 <__wb_calc_thresh+265>: shr $0x2,%rdx 0xffffffff811c37fd <__wb_calc_thresh+269>: mov %rdx,%r10 This series uses div64_ul() instead of div_u64() if the divisor is unsigned long, to avoid truncation to 32-bit on 64-bit platforms. This patch (of 3): The variables 'min' and 'max' are unsigned long and do_div truncates them to 32 bits, which means it can test non-zero and be truncated to zero for division. Fix this issue by using div64_ul() instead. Link: http://lkml.kernel.org/r/20200102081442.8273-2-wenyang@linux.alibaba.com Fixes: 693108a8a667 ("writeback: make bdi->min/max_ratio handling cgroup writeback aware") Signed-off-by: Wen Yang <wenyang@linux.alibaba.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Qian Cai <cai@lca.pw> Cc: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-13mm, debug_pagealloc: don't rely on static keys too earlyVlastimil Babka
Commit 96a2b03f281d ("mm, debug_pagelloc: use static keys to enable debugging") has introduced a static key to reduce overhead when debug_pagealloc is compiled in but not enabled. It relied on the assumption that jump_label_init() is called before parse_early_param() as in start_kernel(), so when the "debug_pagealloc=on" option is parsed, it is safe to enable the static key. However, it turns out multiple architectures call parse_early_param() earlier from their setup_arch(). x86 also calls jump_label_init() even earlier, so no issue was found while testing the commit, but same is not true for e.g. ppc64 and s390 where the kernel would not boot with debug_pagealloc=on as found by our QA. To fix this without tricky changes to init code of multiple architectures, this patch partially reverts the static key conversion from 96a2b03f281d. Init-time and non-fastpath calls (such as in arch code) of debug_pagealloc_enabled() will again test a simple bool variable. Fastpath mm code is converted to a new debug_pagealloc_enabled_static() variant that relies on the static key, which is enabled in a well-defined point in mm_init() where it's guaranteed that jump_label_init() has been called, regardless of architecture. [sfr@canb.auug.org.au: export _debug_pagealloc_enabled_early] Link: http://lkml.kernel.org/r/20200106164944.063ac07b@canb.auug.org.au Link: http://lkml.kernel.org/r/20191219130612.23171-1-vbabka@suse.cz Fixes: 96a2b03f281d ("mm, debug_pagelloc: use static keys to enable debugging") Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Qian Cai <cai@lca.pw> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-13mm: memcg/slab: fix percpu slab vmstats flushingRoman Gushchin
Currently slab percpu vmstats are flushed twice: during the memcg offlining and just before freeing the memcg structure. Each time percpu counters are summed, added to the atomic counterparts and propagated up by the cgroup tree. The second flushing is required due to how recursive vmstats are implemented: counters are batched in percpu variables on a local level, and once a percpu value is crossing some predefined threshold, it spills over to atomic values on the local and each ascendant levels. It means that without flushing some numbers cached in percpu variables will be dropped on floor each time a cgroup is destroyed. And with uptime the error on upper levels might become noticeable. The first flushing aims to make counters on ancestor levels more precise. Dying cgroups may resume in the dying state for a long time. After kmem_cache reparenting which is performed during the offlining slab counters of the dying cgroup don't have any chances to be updated, because any slab operations will be performed on the parent level. It means that the inaccuracy caused by percpu batching will not decrease up to the final destruction of the cgroup. By the original idea flushing slab counters during the offlining should minimize the visible inaccuracy of slab counters on the parent level. The problem is that percpu counters are not zeroed after the first flushing. So every cached percpu value is summed twice. It creates a small error (up to 32 pages per cpu, but usually less) which accumulates on parent cgroup level. After creating and destroying of thousands of child cgroups, slab counter on parent level can be way off the real value. For now, let's just stop flushing slab counters on memcg offlining. It can't be done correctly without scheduling a work on each cpu: reading and zeroing it during css offlining can race with an asynchronous update, which doesn't expect values to be changed underneath. With this change, slab counters on parent level will become eventually consistent. Once all dying children are gone, values are correct. And if not, the error is capped by 32 * NR_CPUS pages per dying cgroup. It's not perfect, as slab are reparented, so any updates after the reparenting will happen on the parent level. It means that if a slab page was allocated, a counter on child level was bumped, then the page was reparented and freed, the annihilation of positive and negative counter values will not happen until the child cgroup is released. It makes slab counters different from others, and it might want us to implement flushing in a correct form again. But it's also a question of performance: scheduling a work on each cpu isn't free, and it's an open question if the benefit of having more accurate counters is worth it. We might also consider flushing all counters on offlining, not only slab counters. So let's fix the main problem now: make the slab counters eventually consistent, so at least the error won't grow with uptime (or more precisely the number of created and destroyed cgroups). And think about the accuracy of counters separately. Link: http://lkml.kernel.org/r/20191220042728.1045881-1-guro@fb.com Fixes: bee07b33db78 ("mm: memcontrol: flush percpu slab vmstats on kmem offlining") Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Michal Hocko <mhocko@suse.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-13mm/shmem.c: thp, shmem: fix conflict of above-47bit hint address and PMD ↵Kirill A. Shutemov
alignment Shmem/tmpfs tries to provide THP-friendly mappings if huge pages are enabled. But it doesn't work well with above-47bit hint address. Normally, the kernel doesn't create userspace mappings above 47-bit, even if the machine allows this (such as with 5-level paging on x86-64). Not all user space is ready to handle wide addresses. It's known that at least some JIT compilers use higher bits in pointers to encode their information. Userspace can ask for allocation from full address space by specifying hint address (with or without MAP_FIXED) above 47-bits. If the application doesn't need a particular address, but wants to allocate from whole address space it can specify -1 as a hint address. Unfortunately, this trick breaks THP alignment in shmem/tmp: shmem_get_unmapped_area() would not try to allocate PMD-aligned area if *any* hint address specified. This can be fixed by requesting the aligned area if the we failed to allocated at user-specified hint address. The request with inflated length will also take the user-specified hint address. This way we will not lose an allocation request from the full address space. [kirill@shutemov.name: fold in a fixup] Link: http://lkml.kernel.org/r/20191223231309.t6bh5hkbmokihpfu@box Link: http://lkml.kernel.org/r/20191220142548.7118-3-kirill.shutemov@linux.intel.com Fixes: b569bab78d8d ("x86/mm: Prepare to expose larger address space to userspace") Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: "Willhalm, Thomas" <thomas.willhalm@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: "Bruggeman, Otto G" <otto.g.bruggeman@intel.com> Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-13mm/huge_memory.c: thp: fix conflict of above-47bit hint address and PMD ↵Kirill A. Shutemov
alignment Patch series "Fix two above-47bit hint address vs. THP bugs". The two get_unmapped_area() implementations have to be fixed to provide THP-friendly mappings if above-47bit hint address is specified. This patch (of 2): Filesystems use thp_get_unmapped_area() to provide THP-friendly mappings. For DAX in particular. Normally, the kernel doesn't create userspace mappings above 47-bit, even if the machine allows this (such as with 5-level paging on x86-64). Not all user space is ready to handle wide addresses. It's known that at least some JIT compilers use higher bits in pointers to encode their information. Userspace can ask for allocation from full address space by specifying hint address (with or without MAP_FIXED) above 47-bits. If the application doesn't need a particular address, but wants to allocate from whole address space it can specify -1 as a hint address. Unfortunately, this trick breaks thp_get_unmapped_area(): the function would not try to allocate PMD-aligned area if *any* hint address specified. Modify the routine to handle it correctly: - Try to allocate the space at the specified hint address with length padding required for PMD alignment. - If failed, retry without length padding (but with the same hint address); - If the returned address matches the hint address return it. - Otherwise, align the address as required for THP and return. The user specified hint address is passed down to get_unmapped_area() so above-47bit hint address will be taken into account without breaking alignment requirements. Link: http://lkml.kernel.org/r/20191220142548.7118-2-kirill.shutemov@linux.intel.com Fixes: b569bab78d8d ("x86/mm: Prepare to expose larger address space to userspace") Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reported-by: Thomas Willhalm <thomas.willhalm@intel.com> Tested-by: Dan Williams <dan.j.williams@intel.com> Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com> Cc: "Bruggeman, Otto G" <otto.g.bruggeman@intel.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-13mm/memory_hotplug: don't free usage map when removing a re-added early sectionDavid Hildenbrand
When we remove an early section, we don't free the usage map, as the usage maps of other sections are placed into the same page. Once the section is removed, it is no longer an early section (especially, the memmap is freed). When we re-add that section, the usage map is reused, however, it is no longer an early section. When removing that section again, we try to kfree() a usage map that was allocated during early boot - bad. Let's check against PageReserved() to see if we are dealing with an usage map that was allocated during boot. We could also check against !(PageSlab(usage_page) || PageCompound(usage_page)), but PageReserved() is cleaner. Can be triggered using memtrace under ppc64/powernv: $ mount -t debugfs none /sys/kernel/debug/ $ echo 0x20000000 > /sys/kernel/debug/powerpc/memtrace/enable $ echo 0x20000000 > /sys/kernel/debug/powerpc/memtrace/enable ------------[ cut here ]------------ kernel BUG at mm/slub.c:3969! Oops: Exception in kernel mode, sig: 5 [#1] LE PAGE_SIZE=3D64K MMU=3DHash SMP NR_CPUS=3D2048 NUMA PowerNV Modules linked in: CPU: 0 PID: 154 Comm: sh Not tainted 5.5.0-rc2-next-20191216-00005-g0be1dba7b7c0 #61 NIP kfree+0x338/0x3b0 LR section_deactivate+0x138/0x200 Call Trace: section_deactivate+0x138/0x200 __remove_pages+0x114/0x150 arch_remove_memory+0x3c/0x160 try_remove_memory+0x114/0x1a0 __remove_memory+0x20/0x40 memtrace_enable_set+0x254/0x850 simple_attr_write+0x138/0x160 full_proxy_write+0x8c/0x110 __vfs_write+0x38/0x70 vfs_write+0x11c/0x2a0 ksys_write+0x84/0x140 system_call+0x5c/0x68 ---[ end trace 4b053cbd84e0db62 ]--- The first invocation will offline+remove memory blocks. The second invocation will first add+online them again, in order to offline+remove them again (usually we are lucky and the exact same memory blocks will get "reallocated"). Tested on powernv with boot memory: The usage map will not get freed. Tested on x86-64 with DIMMs: The usage map will get freed. Using Dynamic Memory under a Power DLAPR can trigger it easily. Triggering removal (I assume after previously removed+re-added) of memory from the HMC GUI can crash the kernel with the same call trace and is fixed by this patch. Link: http://lkml.kernel.org/r/20191217104637.5509-1-david@redhat.com Fixes: 326e1b8f83a4 ("mm/sparsemem: introduce a SECTION_IS_EARLY flag") Signed-off-by: David Hildenbrand <david@redhat.com> Tested-by: Pingfan Liu <piliu@redhat.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-13mm, thp: tweak reclaim/compaction effort of local-only and all-node allocationsVlastimil Babka
THP page faults now attempt a __GFP_THISNODE allocation first, which should only compact existing free memory, followed by another attempt that can allocate from any node using reclaim/compaction effort specified by global defrag setting and madvise. This patch makes the following changes to the scheme: - Before the patch, the first allocation relies on a check for pageblock order and __GFP_IO to prevent excessive reclaim. This however affects also the second attempt, which is not limited to single node. Instead of that, reuse the existing check for costly order __GFP_NORETRY allocations, and make sure the first THP attempt uses __GFP_NORETRY. As a side-effect, all costly order __GFP_NORETRY allocations will bail out if compaction needs reclaim, while previously they only bailed out when compaction was deferred due to previous failures. This should be still acceptable within the __GFP_NORETRY semantics. - Before the patch, the second allocation attempt (on all nodes) was passing __GFP_NORETRY. This is redundant as the check for pageblock order (discussed above) was stronger. It's also contrary to madvise(MADV_HUGEPAGE) which means some effort to allocate THP is requested. After this patch, the second attempt doesn't pass __GFP_THISNODE nor __GFP_NORETRY. To sum up, THP page faults now try the following attempts: 1. local node only THP allocation with no reclaim, just compaction. 2. for madvised VMA's or when synchronous compaction is enabled always - THP allocation from any node with effort determined by global defrag setting and VMA madvise 3. fallback to base pages on any node Link: http://lkml.kernel.org/r/08a3f4dd-c3ce-0009-86c5-9ee51aba8557@suse.cz Fixes: b39d0ee2632d ("mm, page_alloc: avoid expensive reclaim when compaction may not succeed") Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-10Merge branch 'x86/mm' into efi/core, to pick up dependenciesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-01-06arm64: Revert support for execute-only user mappingsCatalin Marinas
The ARMv8 64-bit architecture supports execute-only user permissions by clearing the PTE_USER and PTE_UXN bits, practically making it a mostly privileged mapping but from which user running at EL0 can still execute. The downside, however, is that the kernel at EL1 inadvertently reading such mapping would not trip over the PAN (privileged access never) protection. Revert the relevant bits from commit cab15ce604e5 ("arm64: Introduce execute-only page access permissions") so that PROT_EXEC implies PROT_READ (and therefore PTE_USER) until the architecture gains proper support for execute-only user mappings. Fixes: cab15ce604e5 ("arm64: Introduce execute-only page access permissions") Cc: <stable@vger.kernel.org> # 4.9.x- Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-04mm/hugetlb: defer freeing of huge pages if in non-task contextWaiman Long
The following lockdep splat was observed when a certain hugetlbfs test was run: ================================ WARNING: inconsistent lock state 4.18.0-159.el8.x86_64+debug #1 Tainted: G W --------- - - -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. swapper/30/0 [HC0[0]:SC1[1]:HE1:SE0] takes: ffffffff9acdc038 (hugetlb_lock){+.?.}, at: free_huge_page+0x36f/0xaa0 {SOFTIRQ-ON-W} state was registered at: lock_acquire+0x14f/0x3b0 _raw_spin_lock+0x30/0x70 __nr_hugepages_store_common+0x11b/0xb30 hugetlb_sysctl_handler_common+0x209/0x2d0 proc_sys_call_handler+0x37f/0x450 vfs_write+0x157/0x460 ksys_write+0xb8/0x170 do_syscall_64+0xa5/0x4d0 entry_SYSCALL_64_after_hwframe+0x6a/0xdf irq event stamp: 691296 hardirqs last enabled at (691296): [<ffffffff99bb034b>] _raw_spin_unlock_irqrestore+0x4b/0x60 hardirqs last disabled at (691295): [<ffffffff99bb0ad2>] _raw_spin_lock_irqsave+0x22/0x81 softirqs last enabled at (691284): [<ffffffff97ff0c63>] irq_enter+0xc3/0xe0 softirqs last disabled at (691285): [<ffffffff97ff0ebe>] irq_exit+0x23e/0x2b0 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(hugetlb_lock); <Interrupt> lock(hugetlb_lock); *** DEADLOCK *** : Call Trace: <IRQ> __lock_acquire+0x146b/0x48c0 lock_acquire+0x14f/0x3b0 _raw_spin_lock+0x30/0x70 free_huge_page+0x36f/0xaa0 bio_check_pages_dirty+0x2fc/0x5c0 clone_endio+0x17f/0x670 [dm_mod] blk_update_request+0x276/0xe50 scsi_end_request+0x7b/0x6a0 scsi_io_completion+0x1c6/0x1570 blk_done_softirq+0x22e/0x350 __do_softirq+0x23d/0xad8 irq_exit+0x23e/0x2b0 do_IRQ+0x11a/0x200 common_interrupt+0xf/0xf </IRQ> Both the hugetbl_lock and the subpool lock can be acquired in free_huge_page(). One way to solve the problem is to make both locks irq-safe. However, Mike Kravetz had learned that the hugetlb_lock is held for a linear scan of ALL hugetlb pages during a cgroup reparentling operation. So it is just too long to have irq disabled unless we can break hugetbl_lock down into finer-grained locks with shorter lock hold times. Another alternative is to defer the freeing to a workqueue job. This patch implements the deferred freeing by adding a free_hpage_workfn() work function to do the actual freeing. The free_huge_page() call in a non-task context saves the page to be freed in the hpage_freelist linked list in a lockless manner using the llist APIs. The generic workqueue is used to process the work, but a dedicated workqueue can be used instead if it is desirable to have the huge page freed ASAP. Thanks to Kirill Tkhai <ktkhai@virtuozzo.com> for suggesting the use of llist APIs which simplfy the code. Link: http://lkml.kernel.org/r/20191217170331.30893-1-longman@redhat.com Signed-off-by: Waiman Long <longman@redhat.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: Davidlohr Bueso <dbueso@suse.de> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Andi Kleen <ak@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-04mm/gup: fix memory leak in __gup_benchmark_ioctlNavid Emamdoost
In the implementation of __gup_benchmark_ioctl() the allocated pages should be released before returning in case of an invalid cmd. Release pages via kvfree(). [akpm@linux-foundation.org: rework code flow, return -EINVAL rather than -1] Link: http://lkml.kernel.org/r/20191211174653.4102-1-navid.emamdoost@gmail.com Fixes: 714a3a1ebafe ("mm/gup_benchmark.c: add additional pinning methods") Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com> Reviewed-by: