- 12 Aug, 2017 4 commits
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git://git.infradead.org/linux-mtdLinus Torvalds authored
Pull another MTD fix from Brian Norris: "An mtdblock regression occurred in -rc1 (all writes were broken!), in the process of some block subsystem refactoring. Noticed and fixed last week, but I'm a little slow on the uptake" * tag 'for-linus-20170812' of git://git.infradead.org/linux-mtd: mtd: blkdevs: Fix mtd block write failure
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Abhishek Sahu authored
All the MTD block write requests are failing with following error messages mkfs.ext4 /dev/mtdblock0 print_req_error: I/O error, dev mtdblock0, sector 0 Buffer I/O error on dev mtdblock0, logical block 0, lost async page write The control is going to default case after block write request because of missing return. Fixes: commit 2a842aca ("block: introduce new block status code type") Signed-off-by:Abhishek Sahu <absahu@codeaurora.org> Signed-off-by:
Brian Norris <computersforpeace@gmail.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pendingLinus Torvalds authored
Pull SCSI target fixes from Nicholas Bellinger: "The highlights include: - Fix iscsi-target payload memory leak during ISCSI_FLAG_TEXT_CONTINUE (Varun Prakash) - Fix tcm_qla2xxx incorrect use of tcm_qla2xxx_free_cmd during ABORT (Pascal de Bruijn + Himanshu Madhani + nab) - Fix iscsi-target long-standing issue with parallel delete of a single network portal across multiple target instances (Gary Guo + nab) - Fix target dynamic se_node GPF during uncached shutdown regression (Justin Maggard + nab)" * git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: target: Fix node_acl demo-mode + uncached dynamic shutdown regression iscsi-target: Fix iscsi_np reset hung task during parallel delete qla2xxx: Fix incorrect tcm_qla2xxx_free_cmd use during TMR ABORT (v2) cxgbit: fix sg_nents calculation iscsi-target: fix invalid flags in text response iscsi-target: fix memory leak in iscsit_setup_text_cmd() cxgbit: add missing __kfree_skb() tcmu: free old string on reconfig tcmu: Fix possible to/from address overflow when doing the memcpy -
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tipLinus Torvalds authored
Pull xen fixes from Juergen Gross: "Some fixes for Xen: - a fix for a regression introduced in 4.13 for a Xen HVM-guest configured with KASLR - a fix for a possible deadlock in the xenbus driver when booting the system - a fix for lost interrupts in Xen guests" * tag 'for-linus-4.13b-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/events: Fix interrupt lost during irq_disable and irq_enable xen: avoid deadlock in xenbus xen: fix hvm guest with kaslr enabled xen: split up xen_hvm_init_shared_info() x86: provide an init_mem_mapping hypervisor hook
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- 11 Aug, 2017 17 commits
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git://git.linux-nfs.org/projects/anna/linux-nfsLinus Torvalds authored
Pull NFS client fixes from Anna Schumaker: "A few more NFS client bugfixes from me for rc5. Dros has a stable fix for flexfiles to prevent leaking the nfs4_ff_ds_version arrays when freeing a layout, Trond fixed a potential recovery loop situation with the TEST_STATEID operation, and Christoph fixed up the pNFS blocklayout Kconfig options to prevent unsafe use with kernels that don't have large block device support. Summary: Stable fix: - fix leaking nfs4_ff_ds_version array Other fixes: - improve TEST_STATEID OLD_STATEID handling to prevent recovery loop - require 64-bit sector_t for pNFS blocklayout to prevent 32-bit compile errors" * tag 'nfs-for-4.13-5' of git://git.linux-nfs.org/projects/anna/linux-nfs: pnfs/blocklayout: require 64-bit sector_t NFSv4: Ignore NFS4ERR_OLD_STATEID in nfs41_check_open_stateid() nfs/flexfiles: fix leak of nfs4_ff_ds_version arrays -
git://git.kernel.dk/linux-blockLinus Torvalds authored
Pull block fixes from Jens Axboe: "A set of fixes that should go into this series. This contains: - Fix from Bart for blk-mq requeue queue running, preventing a continued loop of run/restart. - Fix for a bio/blk-integrity issue, in two parts. One from Christoph, fixing where verification happens, and one from Milan, for a NULL profile. - NVMe pull request, most of the changes being for nvme-fc, but also a few trivial core/pci fixes" * 'for-linus' of git://git.kernel.dk/linux-block: nvme: fix directive command numd calculation nvme: fix nvme reset command timeout handling nvme-pci: fix CMB sysfs file removal in reset path lpfc: support nvmet_fc defer_rcv callback nvmet_fc: add defer_req callback for deferment of cmd buffer return nvme: strip trailing 0-bytes in wwid_show block: Make blk_mq_delay_kick_requeue_list() rerun the queue at a quiet time bio-integrity: only verify integrity on the lowest stacked driver bio-integrity: Fix regression if profile verify_fn is NULL -
git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmcLinus Torvalds authored
Pull MMC fixes from Ulf Hansson: "MMC core: - fix lockdep splat when removing mmc_block module - fix the logic for setting eMMC HS400ES signal voltage MMC host: - omap_hsmmc: add CMD23 capability to fix -EIO errors" * tag 'mmc-v4.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc: mmc: block: fix lockdep splat when removing mmc_block module mmc: mmc: correct the logic for setting HS400ES signal voltage mmc: host: omap_hsmmc: Add CMD23 capability to omap_hsmmc driver
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git://github.com/bzolnier/linuxLinus Torvalds authored
Pull fbdev fixes from Bartlomiej Zolnierkiewicz: - allow user to disable write combined mapping in efifb driver (Dave Airlie) - fix use after free bugs on driver removal in imxfb driver (Dan Carpenter) - fix unused variable warning in omapfb driver (Arnd Bergmann) * tag 'fbdev-v4.13-rc5' of git://github.com/bzolnier/linux: efifb: allow user to disable write combined mapping. fbdev: omapfb: remove unused variable video: fbdev: imxfb: use after free in imxfb_remove()
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git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuseLinus Torvalds authored
Pull fuse fixes from Miklos Szeredi: "Fix a few bugs in fuse" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: fuse: set mapping error in writepage_locked when it fails fuse: Dont call set_page_dirty_lock() for ITER_BVEC pages for async_dio fuse: initialize the flock flag in fuse_file on allocation
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git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommuLinus Torvalds authored
Pull IOMMU fix from Joerg Roedel: "Fix a NULL-pointer dereference in arm_smmu_add_device" * tag 'iommu-fixes-v4.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: iommu/arm-smmu: fix null-pointer dereference in arm_smmu_add_device
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Christoph Hellwig authored
The blocklayout code does not compile cleanly for a 32-bit sector_t, and also has no reliable checks for devices sizes, which makes it unsafe to use with a kernel that doesn't support large block devices. Signed-off-by:
Christoph Hellwig <hch@lst.de> Reported-by:
Arnd Bergmann <arnd@arndb.de> Fixes: 5c83746a ("pnfs/blocklayout: in-kernel GETDEVICEINFO XDR parsing") Signed-off-by:
Anna Schumaker <Anna.Schumaker@Netapp.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linuxLinus Torvalds authored
Pull powerpc fixes from Michael Ellerman: "All fixes for code that went in this cycle. - a revert of an optimisation to the syscall exit path, which could lead to an oops on either older machines or machines with > 1TB of memory - disable some deep idle states if the firmware configuration for them fails - re-enable HARD/SOFT lockup detectors in defconfigs after a Kconfig change - six fairly small patches fixing bugs in our new watchdog code Thanks to: Gautham R Shenoy, Nicholas Piggin" * tag 'powerpc-4.13-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/watchdog: add locking around init/exit functions powerpc/watchdog: Fix marking of stuck CPUs powerpc/watchdog: Fix final-check recovered case powerpc/watchdog: Moderate touch_nmi_watchdog overhead powerpc/watchdog: Improve watchdog lock primitive powerpc: NMI IPI improve lock primitive powerpc/configs: Re-enable HARD/SOFT lockup detectors powerpc/powernv/idle: Disable LOSE_FULL_CONTEXT states when stop-api fails Revert "powerpc/64: Avoid restore_math call if possible in syscall exit" -
Artem Savkov authored
Commit c54451a5 "iommu/arm-smmu: Fix the error path in arm_smmu_add_device" removed fwspec assignment in legacy_binding path as redundant which is wrong. It needs to be updated after fwspec initialisation in arm_smmu_register_legacy_master() as it is dereferenced later. Without this there is a NULL-pointer dereference panic during boot on some hosts. Signed-off-by:
Artem Savkov <asavkov@redhat.com> Reviewed-by:
Robin Murphy <robin.murphy@arm.com> Acked-by:
Will Deacon <will.deacon@arm.com> Signed-off-by:
Joerg Roedel <jroedel@suse.de>
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Liu Shuo authored
Here is a device has xen-pirq-MSI interrupt. Dom0 might lost interrupt during driver irq_disable/irq_enable. Here is the scenario, 1. irq_disable -> disable_dynirq -> mask_evtchn(irq channel) 2. dev interrupt raised by HW and Xen mark its evtchn as pending 3. irq_enable -> startup_pirq -> eoi_pirq -> clear_evtchn(channel of irq) -> clear pending status 4. consume_one_event process the irq event without pending bit assert which result in interrupt lost once 5. No HW interrupt raising anymore. Now use enable_dynirq for enable_pirq of xen_pirq_chip to remove eoi_pirq when irq_enable. Signed-off-by:Liu Shuo <shuo.a.liu@intel.com> Reviewed-by:
Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by:
Juergen Gross <jgross@suse.com>
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Juergen Gross authored
When starting the xenwatch thread a theoretical deadlock situation is possible: xs_init() contains: task = kthread_run(xenwatch_thread, NULL, "xenwatch"); if (IS_ERR(task)) return PTR_ERR(task); xenwatch_pid = task->pid; And xenwatch_thread() does: mutex_lock(&xenwatch_mutex); ... event->handle->callback(); ... mutex_unlock(&xenwatch_mutex); The callback could call unregister_xenbus_watch() which does: ... if (current->pid != xenwatch_pid) mutex_lock(&xenwatch_mutex); ... In case a watch is firing before xenwatch_pid could be set and the callback of that watch unregisters a watch, then a self-deadlock would occur. Avoid this by setting xenwatch_pid in xenwatch_thread(). Signed-off-by: -
git://git.infradead.org/nvmeJens Axboe authored
Pull NVMe fixes from Christoph: "A few more small fixes - the fc/lpfc update is the biggest by far."
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Juergen Gross authored
A Xen HVM guest running with KASLR enabled will die rather soon today because the shared info page mapping is using va() too early. This was introduced by commit a5d5f328 ("xen: allocate page for shared info page from low memory"). In order to fix this use early_memremap() to get a temporary virtual address for shared info until va() can be used safely. Signed-off-by:
Ingo Molnar <mingo@kernel.org> Signed-off-by:
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Juergen Gross authored
Instead of calling xen_hvm_init_shared_info() on boot and resume split it up into a boot time function searching for the pfn to use and a mapping function doing the hypervisor mapping call. Signed-off-by:
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Juergen Gross authored
Provide a hook in hypervisor_x86 called after setting up initial memory mapping. This is needed e.g. by Xen HVM guests to map the hypervisor shared info page. Signed-off-by:
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Jeff Layton authored
This ensures that we see errors on fsync when writeback fails. Signed-off-by:
Jeff Layton <jlayton@redhat.com> Reviewed-by:
Jan Kara <jack@suse.cz> Signed-off-by:
Miklos Szeredi <mszeredi@redhat.com>
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git://people.freedesktop.org/~airlied/linuxLinus Torvalds authored
Pull drm fixes from Dave Airlie: "Nothing too earth shattering here, it just seems like lots of little things all over the place. msm has probably the larger amount of changes, but they all seem fine, otherwise, some rockchip, i915, etnaviv and exynos fixes, along with one nouveau regression fix for some older GPUs" * tag 'drm-fixes-for-v4.13-rc5' of git://people.freedesktop.org/~airlied/linux: (35 commits) drm/nouveau/disp/nv04: avoid creation of output paths drm: make DRM_STM default n drm/exynos: forbid creating framebuffers from too small GEM buffers drm/etnaviv: Fix off-by-one error in reloc checking drm/i915: fix backlight invert for non-zero minimum brightness drm/i915/shrinker: Wrap need_resched() inside preempt-disable drm/i915/perf: fix flex eu registers programming drm/i915: Fix out-of-bounds array access in bdw_load_gamma_lut drm/i915/gvt: Change the max length of mmio_reg_rw from 4 to 8 drm/i915/gvt: Initialize MMIO Block with HW state drm/rockchip: vop: report error when check resource error drm/rockchip: vop: round_up pitches to word align drm/rockchip: vop: fix NV12 video display error drm/rockchip: vop: fix iommu page fault when resume drm/i915/gvt: clean workload queue if error happened drm/i915/gvt: change resetting to resetting_eng drm/msm: gpu: don't abuse dma_alloc for non-DMA allocations drm/msm: gpu: call qcom_mdt interfaces only for ARCH_QCOM drm/msm/adreno: Prevent unclocked access when retrieving timestamps drm/msm: Remove __user from __u64 data types ...
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- 10 Aug, 2017 19 commits
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Linus Torvalds authored
Merge misc fixes from Andrew Morton: "21 fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (21 commits) userfaultfd: replace ENOSPC with ESRCH in case mm has gone during copy/zeropage zram: rework copy of compressor name in comp_algorithm_store() rmap: do not call mmu_notifier_invalidate_page() under ptl mm: fix list corruptions on shmem shrinklist mm/balloon_compaction.c: don't zero ballooned pages MAINTAINERS: copy virtio on balloon_compaction.c mm: fix KSM data corruption mm: fix MADV_[FREE|DONTNEED] TLB flush miss problem mm: make tlb_flush_pending global mm: refactor TLB gathering API Revert "mm: numa: defer TLB flush for THP migration as long as possible" mm: migrate: fix barriers around tlb_flush_pending mm: migrate: prevent racy access to tlb_flush_pending fault-inject: fix wrong should_fail() decision in task context test_kmod: fix small memory leak on filesystem tests test_kmod: fix the lock in register_test_dev_kmod() test_kmod: fix bug which allows negative values on two config options test_kmod: fix spelling mistake: "EMTPY" -> "EMPTY" userfaultfd: hugetlbfs: remove superfluous page unlock in VM_SHARED case mm: ratelimit PFNs busy info message ...
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Mike Rapoport authored
When the process exit races with outstanding mcopy_atomic, it would be better to return ESRCH error. When such race occurs the process and it's mm are going away and returning "no such process" to the uffd monitor seems better fit than ENOSPC. Link: http://lkml.kernel.org/r/1502111545-32305-1-git-send-email-rppt@linux.vnet.ibm.comSigned-off-by:
Mike Rapoport <rppt@linux.vnet.ibm.com> Suggested-by:
Michal Hocko <mhocko@suse.com> Acked-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Matthias Kaehlcke authored
comp_algorithm_store() passes the size of the source buffer to strlcpy() instead of the destination buffer size. Make it explicit that the two buffers have the same size and use strcpy() instead of strlcpy(). The latter can be done safely since the function ensures that the string in the source buffer is terminated. Link: http://lkml.kernel.org/r/20170803163350.45245-1-mka@chromium.orgSigned-off-by:
Matthias Kaehlcke <mka@chromium.org> Reviewed-by:
Douglas Anderson <dianders@chromium.org> Reviewed-by:
Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by:
Minchan Kim <minchan@kernel.org> Signed-off-by:
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Kirill A. Shutemov authored
MMU notifiers can sleep, but in page_mkclean_one() we call mmu_notifier_invalidate_page() under page table lock. Let's instead use mmu_notifier_invalidate_range() outside page_vma_mapped_walk() loop. [jglisse@redhat.com: try_to_unmap_one() do not call mmu_notifier under ptl] Link: http://lkml.kernel.org/r/20170809204333.27485-1-jglisse@redhat.com Link: http://lkml.kernel.org/r/20170804134928.l4klfcnqatni7vsc@black.fi.intel.com Fixes: c7ab0d2f ("mm: convert try_to_unmap_one() to use page_vma_mapped_walk()") Signed-off-by:
Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by:
Jérôme Glisse <jglisse@redhat.com> Reported-by:
axie <axie@amd.com> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: "Writer, Tim" <Tim.Writer@amd.com> Cc: <stable@vger.kernel.org> Signed-off-by:
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Cong Wang authored
We saw many list corruption warnings on shmem shrinklist: WARNING: CPU: 18 PID: 177 at lib/list_debug.c:59 __list_del_entry+0x9e/0xc0 list_del corruption. prev->next should be ffff9ae5694b82d8, but was ffff9ae5699ba960 Modules linked in: intel_rapl sb_edac edac_core x86_pkg_temp_thermal coretemp iTCO_wdt iTCO_vendor_support crct10dif_pclmul crc32_pclmul ghash_clmulni_intel raid0 dcdbas shpchp wmi hed i2c_i801 ioatdma lpc_ich i2c_smbus acpi_cpufreq tcp_diag inet_diag sch_fq_codel ipmi_si ipmi_devintf ipmi_msghandler igb ptp crc32c_intel pps_core i2c_algo_bit i2c_core dca ipv6 crc_ccitt CPU: 18 PID: 177 Comm: kswapd1 Not tainted 4.9.34-t3.el7.twitter.x86_64 #1 Hardware name: Dell Inc. PowerEdge C6220/0W6W6G, BIOS 2.2.3 11/07/2013 Call Trace: dump_stack+0x4d/0x66 __warn+0xcb/0xf0 warn_slowpath_fmt+0x4f/0x60 __list_del_entry+0x9e/0xc0 shmem_unused_huge_shrink+0xfa/0x2e0 shmem_unused_huge_scan+0x20/0x30 super_cache_scan+0x193/0x1a0 shrink_slab.part.41+0x1e3/0x3f0 shrink_slab+0x29/0x30 shrink_node+0xf9/0x2f0 kswapd+0x2d8/0x6c0 kthread+0xd7/0xf0 ret_from_fork+0x22/0x30 WARNING: CPU: 23 PID: 639 at lib/list_debug.c:33 __list_add+0x89/0xb0 list_add corruption. prev->next should be next (ffff9ae5699ba960), but was ffff9ae5694b82d8. (prev=ffff9ae5694b82d8). Modules linked in: intel_rapl sb_edac edac_core x86_pkg_temp_thermal coretemp iTCO_wdt iTCO_vendor_support crct10dif_pclmul crc32_pclmul ghash_clmulni_intel raid0 dcdbas shpchp wmi hed i2c_i801 ioatdma lpc_ich i2c_smbus acpi_cpufreq tcp_diag inet_diag sch_fq_codel ipmi_si ipmi_devintf ipmi_msghandler igb ptp crc32c_intel pps_core i2c_algo_bit i2c_core dca ipv6 crc_ccitt CPU: 23 PID: 639 Comm: systemd-udevd Tainted: G W 4.9.34-t3.el7.twitter.x86_64 #1 Hardware name: Dell Inc. PowerEdge C6220/0W6W6G, BIOS 2.2.3 11/07/2013 Call Trace: dump_stack+0x4d/0x66 __warn+0xcb/0xf0 warn_slowpath_fmt+0x4f/0x60 __list_add+0x89/0xb0 shmem_setattr+0x204/0x230 notify_change+0x2ef/0x440 do_truncate+0x5d/0x90 path_openat+0x331/0x1190 do_filp_open+0x7e/0xe0 do_sys_open+0x123/0x200 SyS_open+0x1e/0x20 do_syscall_64+0x61/0x170 entry_SYSCALL64_slow_path+0x25/0x25 The problem is that shmem_unused_huge_shrink() moves entries from the global sbinfo->shrinklist to its local lists and then releases the spinlock. However, a parallel shmem_setattr() could access one of these entries directly and add it back to the global shrinklist if it is removed, with the spinlock held. The logic itself looks solid since an entry could be either in a local list or the global list, otherwise it is removed from one of them by list_del_init(). So probably the race condition is that, one CPU is in the middle of INIT_LIST_HEAD() but the other CPU calls list_empty() which returns true too early then the following list_add_tail() sees a corrupted entry. list_empty_careful() is designed to fix this situation. [akpm@linux-foundation.org: add comments] Link: http://lkml.kernel.org/r/20170803054630.18775-1-xiyou.wangcong@gmail.com Fixes: 779750d2 ("shmem: split huge pages beyond i_size under memory pressure") Signed-off-by:Cong Wang <xiyou.wangcong@gmail.com> Acked-by:
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Wei Wang authored
Revert commit bb01b64c ("mm/balloon_compaction.c: enqueue zero page to balloon device")' Zeroing ballon pages is rather time consuming, especially when a lot of pages are in flight. E.g. 7GB worth of ballooned memory takes 2.8s with __GFP_ZERO while it takes ~491ms without it. The original commit argued that zeroing will help ksmd to merge these pages on the host but this argument is assuming that the host actually marks balloon pages for ksm which is not universally true. So we pay performance penalty for something that even might not be used in the end which is wrong. The host can zero out pages on its own when there is a need. [mhocko@kernel.org: new changelog text] Link: http://lkml.kernel.org/r/1501761557-9758-1-git-send-email-wei.w.wang@intel.com Fixes: bb01b64c ("mm/balloon_compaction.c: enqueue zero page to balloon device") Signed-off-by:
Wei Wang <wei.w.wang@intel.com> Acked-by:
Michael S. Tsirkin <mst@redhat.com> Acked-by:
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Michael S. Tsirkin authored
Changes to mm/balloon_compaction.c can easily break virtio, and virtio is the only user of that interface. Add a line to MAINTAINERS so whoever changes that file remembers to copy us. Link: http://lkml.kernel.org/r/1501764010-24456-1-git-send-email-mst@redhat.comSigned-off-by:
Rafael Aquini <aquini@redhat.com> Acked-by:
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Minchan Kim authored
Nadav reported KSM can corrupt the user data by the TLB batching race[1]. That means data user written can be lost. Quote from Nadav Amit: "For this race we need 4 CPUs: CPU0: Caches a writable and dirty PTE entry, and uses the stale value for write later. CPU1: Runs madvise_free on the range that includes the PTE. It would clear the dirty-bit. It batches TLB flushes. CPU2: Writes 4 to /proc/PID/clear_refs , clearing the PTEs soft-dirty. We care about the fact that it clears the PTE write-bit, and of course, batches TLB flushes. CPU3: Runs KSM. Our purpose is to pass the following test in write_protect_page(): if (pte_write(*pvmw.pte) || pte_dirty(*pvmw.pte) || (pte_protnone(*pvmw.pte) && pte_savedwrite(*pvmw.pte))) Since it will avoid TLB flush. And we want to do it while the PTE is stale. Later, and before replacing the page, we would be able to change the page. Note that all the operations the CPU1-3 perform canhappen in parallel since they only acquire mmap_sem for read. We start with two identical pages. Everything below regards the same page/PTE. CPU0 CPU1 CPU2 CPU3 ---- ---- ---- ---- Write the same value on page [cache PTE as dirty in TLB] MADV_FREE pte_mkclean() 4 > clear_refs pte_wrprotect() write_protect_page() [ success, no flush ] pages_indentical() [ ok ] Write to page different value [Ok, using stale PTE] replace_page() Later, CPU1, CPU2 and CPU3 would flush the TLB, but that is too late. CPU0 already wrote on the page, but KSM ignored this write, and it got lost" In above scenario, MADV_FREE is fixed by changing TLB batching API including [set|clear]_tlb_flush_pending. Remained thing is soft-dirty part. This patch changes soft-dirty uses TLB batching API instead of flush_tlb_mm and KSM checks pending TLB flush by using mm_tlb_flush_pending so that it will flush TLB to avoid data lost if there are other parallel threads pending TLB flush. [1] http://lkml.kernel.org/r/BD3A0EBE-ECF4-41D4-87FA-C755EA9AB6BD@gmail.com Link: http://lkml.kernel.org/r/20170802000818.4760-8-namit@vmware.comSigned-off-by:Nadav Amit <namit@vmware.com> Reported-by:
Andrea Arcangeli <aarcange@redhat.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Hugh Dickins <hughd@google.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Rik van Riel <riel@redhat.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by:
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Minchan Kim authored
Nadav reported parallel MADV_DONTNEED on same range has a stale TLB problem and Mel fixed it[1] and found same problem on MADV_FREE[2]. Quote from Mel Gorman: "The race in question is CPU 0 running madv_free and updating some PTEs while CPU 1 is also running madv_free and looking at the same PTEs. CPU 1 may have writable TLB entries for a page but fail the pte_dirty check (because CPU 0 has updated it already) and potentially fail to flush. Hence, when madv_free on CPU 1 returns, there are still potentially writable TLB entries and the underlying PTE is still present so that a subsequent write does not necessarily propagate the dirty bit to the underlying PTE any more. Reclaim at some unknown time at the future may then see that the PTE is still clean and discard the page even though a write has happened in the meantime. I think this is possible but I could have missed some protection in madv_free that prevents it happening." This patch aims for solving both problems all at once and is ready for other problem with KSM, MADV_FREE and soft-dirty story[3]. TLB batch API(tlb_[gather|finish]_mmu] uses [inc|dec]_tlb_flush_pending and mmu_tlb_flush_pending so that when tlb_finish_mmu is called, we can catch there are parallel threads going on. In that case, forcefully, flush TLB to prevent for user to access memory via stale TLB entry although it fail to gather page table entry. I confirmed this patch works with [4] test program Nadav gave so this patch supersedes "mm: Always flush VMA ranges affected by zap_page_range v2" in current mmotm. NOTE: This patch modifies arch-specific TLB gathering interface(x86, ia64, s390, sh, um). It seems most of architecture are straightforward but s390 need to be careful because tlb_flush_mmu works only if mm->context.flush_mm is set to non-zero which happens only a pte entry really is cleared by ptep_get_and_clear and friends. However, this problem never changes the pte entries but need to flush to prevent memory access from stale tlb. [1] http://lkml.kernel.org/r/20170725101230.5v7gvnjmcnkzzql3@techsingularity.net [2] http://lkml.kernel.org/r/20170725100722.2dxnmgypmwnrfawp@suse.de [3] http://lkml.kernel.org/r/BD3A0EBE-ECF4-41D4-87FA-C755EA9AB6BD@gmail.com [4] https://patchwork.kernel.org/patch/9861621/ [minchan@kernel.org: decrease tlb flush pending count in tlb_finish_mmu] Link: http://lkml.kernel.org/r/20170808080821.GA31730@bbox Link: http://lkml.kernel.org/r/20170802000818.4760-7-namit@vmware.comSigned-off-by:
Mel Gorman <mgorman@techsingularity.net> Acked-by:
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Minchan Kim authored
Currently, tlb_flush_pending is used only for CONFIG_[NUMA_BALANCING| COMPACTION] but upcoming patches to solve subtle TLB flush batching problem will use it regardless of compaction/NUMA so this patch doesn't remove the dependency. [akpm@linux-foundation.org: remove more ifdefs from world's ugliest printk statement] Link: http://lkml.kernel.org/r/20170802000818.4760-6-namit@vmware.comSigned-off-by:
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Minchan Kim authored
This patch is a preparatory patch for solving race problems caused by TLB batch. For that, we will increase/decrease TLB flush pending count of mm_struct whenever tlb_[gather|finish]_mmu is called. Before making it simple, this patch separates architecture specific part and rename it to arch_tlb_[gather|finish]_mmu and generic part just calls it. It shouldn't change any behavior. Link: http://lkml.kernel.org/r/20170802000818.4760-5-namit@vmware.comSigned-off-by:
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Nadav Amit authored
While deferring TLB flushes is a good practice, the reverted patch caused pending TLB flushes to be checked while the page-table lock is not taken. As a result, in architectures with weak memory model (PPC), Linux may miss a memory-barrier, miss the fact TLB flushes are pending, and cause (in theory) a memory corruption. Since the alternative of using smp_mb__after_unlock_lock() was considered a bit open-coded, and the performance impact is expected to be small, the previous patch is reverted. This reverts b0943d61 ("mm: numa: defer TLB flush for THP migration as long as possible"). Link: http://lkml.kernel.org/r/20170802000818.4760-4-namit@vmware.comSigned-off-by:
Mel Gorman <mgorman@suse.de> Acked-by:
Rik van Riel <riel@redhat.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Tony Luck <tony.luck@intel.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by:
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Nadav Amit authored
Reading tlb_flush_pending while the page-table lock is taken does not require a barrier, since the lock/unlock already acts as a barrier. Removing the barrier in mm_tlb_flush_pending() to address this issue. However, migrate_misplaced_transhuge_page() calls mm_tlb_flush_pending() while the page-table lock is already released, which may present a problem on architectures with weak memory model (PPC). To deal with this case, a new parameter is added to mm_tlb_flush_pending() to indicate if it is read without the page-table lock taken, and calling smp_mb__after_unlock_lock() in this case. Link: http://lkml.kernel.org/r/20170802000818.4760-3-namit@vmware.comSigned-off-by:
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Nadav Amit authored
Patch series "fixes of TLB batching races", v6. It turns out that Linux TLB batching mechanism suffers from various races. Races that are caused due to batching during reclamation were recently handled by Mel and this patch-set deals with others. The more fundamental issue is that concurrent updates of the page-tables allow for TLB flushes to be batched on one core, while another core changes the page-tables. This other core may assume a PTE change does not require a flush based on the updated PTE value, while it is unaware that TLB flushes are still pending. This behavior affects KSM (which may result in memory corruption) and MADV_FREE and MADV_DONTNEED (which may result in incorrect behavior). A proof-of-concept can easily produce the wrong behavior of MADV_DONTNEED. Memory corruption in KSM is harder to produce in practice, but was observed by hacking the kernel and adding a delay before flushing and replacing the KSM page. Finally, there is also one memory barrier missing, which may affect architectures with weak memory model. This patch (of 7): Setting and clearing mm->tlb_flush_pending can be performed by multiple threads, since mmap_sem may only be acquired for read in task_numa_work(). If this happens, tlb_flush_pending might be cleared while one of the threads still changes PTEs and batches TLB flushes. This can lead to the same race between migration and change_protection_range() that led to the introduction of tlb_flush_pending. The result of this race was data corruption, which means that this patch also addresses a theoretically possible data corruption. An actual data corruption was not observed, yet the race was was confirmed by adding assertion to check tlb_flush_pending is not set by two threads, adding artificial latency in change_protection_range() and using sysctl to reduce kernel.numa_balancing_scan_delay_ms. Link: http://lkml.kernel.org/r/20170802000818.4760-2-namit@vmware.com Fixes: 20841405 ("mm: fix TLB flush race between migration, and change_protection_range") Signed-off-by:
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Akinobu Mita authored
Commit 1203c8e6 ("fault-inject: simplify access check for fail-nth") unintentionally broke a conditional statement in should_fail(). Any faults are not injected in the task context by the change when the systematic fault injection is not used. This change restores to the previous correct behaviour. Link: http://lkml.kernel.org/r/1501633700-3488-1-git-send-email-akinobu.mita@gmail.com Fixes: 1203c8e6 ("fault-inject: simplify access check for fail-nth") Signed-off-by:
Akinobu Mita <akinobu.mita@gmail.com> Reported-by:
Lu Fengqi <lufq.fnst@cn.fujitsu.com> Tested-by:
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Dan Carpenter authored
The break was in the wrong place so file system tests don't work as intended, leaking memory at each test switch. [mcgrof@kernel.org: massaged commit subject, noted memory leak issue without the fix] Link: http://lkml.kernel.org/r/20170802211450.27928-6-mcgrof@kernel.org Fixes: 39258f448d71 ("kmod: add test driver to stress test the module loader") Signed-off-by:
Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by:
Luis R. Rodriguez <mcgrof@kernel.org> Reported-by:
David Binderman <dcb314@hotmail.com> Cc: Colin Ian King <colin.king@canonical.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Jessica Yu <jeyu@redhat.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Michal Marek <mmarek@suse.com> Cc: Miroslav Benes <mbenes@suse.cz> Cc: Petr Mladek <pmladek@suse.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by:
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Dan Carpenter authored
We accidentally just drop the lock twice instead of taking it and then releasing it. This isn't a big issue unless you are adding more than one device to test on, and the kmod.sh doesn't do that yet, however this obviously is the correct thing to do. [mcgrof@kernel.org: massaged subject, explain what happens] Link: http://lkml.kernel.org/r/20170802211450.27928-5-mcgrof@kernel.org Fixes: 39258f448d71 ("kmod: add test driver to stress test the module loader") Signed-off-by:
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Luis R. Rodriguez authored
Parsing with kstrtol() enables values to be negative, and we failed to check for negative values when parsing with test_dev_config_update_uint_sync() or test_dev_config_update_uint_range(). test_dev_config_update_uint_range() has a minimum check though so an issue is not present there. test_dev_config_update_uint_sync() is only used for the number of threads to use (config_num_threads_store()), and indeed this would fail with an attempt for a large allocation. Although the issue is only present in practice with the first fix both by using kstrtoul() instead of kstrtol(). Link: http://lkml.kernel.org/r/20170802211450.27928-4-mcgrof@kernel.org Fixes: 39258f448d71 ("kmod: add test driver to stress test the module loader") Signed-off-by:
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Colin Ian King authored
Trivial fix to spelling mistake in snprintf text [mcgrof@kernel.org: massaged commit message] Link: http://lkml.kernel.org/r/20170802211450.27928-3-mcgrof@kernel.org Fixes: 39258f448d71 ("kmod: add test driver to stress test the module loader") Signed-off-by:
Colin Ian King <colin.king@canonical.com> Signed-off-by:
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