- 04 Sep, 2019 4 commits
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Christoph Hellwig authored
Replace the local hack with the dma_can_mmap helper to check if a given device supports mapping DMA allocations to userspace. Signed-off-by:
Christoph Hellwig <hch@lst.de> Reviewed-by:
Takashi Iwai <tiwai@suse.de>
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Christoph Hellwig authored
Add a helper to check if DMA allocations for a specific device can be mapped to userspace using dma_mmap_*. Signed-off-by:
Christoph Hellwig <hch@lst.de>
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Christoph Hellwig authored
While the default ->mmap and ->get_sgtable implementations work for the majority of our dma_map_ops impementations they are inherently safe for others that don't use the page allocator or CMA and/or use their own way of remapping not covered by the common code. So remove the defaults if these methods are not wired up, but instead wire up the default implementations for all safe instances. Fixes: e1c7e324 ("dma-mapping: always provide the dma_map_ops based implementation") Signed-off-by:
Christoph Hellwig <hch@lst.de>
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Christoph Hellwig authored
The comments are spot on and should be near the central API, not just near a single implementation. Signed-off-by:
Christoph Hellwig <hch@lst.de>
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- 03 Sep, 2019 5 commits
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Andy Shevchenko authored
After commit cf65a0f6 ("dma-mapping: move all DMA mapping code to kernel/dma") some of the files are referring to outdated information, i.e. old file names of DMA mapping sources. Fix it here. Note, the lines with "Glue code for..." have been removed completely. Signed-off-by:
Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by:
Christoph Hellwig <hch@lst.de>
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Yoshihiro Shimoda authored
This patch adds a new dma_map_ops of get_merge_boundary() to expose the DMA merge boundary if the domain type is IOMMU_DOMAIN_DMA. Signed-off-by:
Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Reviewed-by:
Simon Horman <horms+renesas@verge.net.au> Acked-by:
Joerg Roedel <jroedel@suse.de> Signed-off-by:
Christoph Hellwig <hch@lst.de>
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Yoshihiro Shimoda authored
This patch adds a new DMA API "dma_get_merge_boundary". This function returns the DMA merge boundary if the DMA layer can merge the segments. This patch also adds the implementation for a new dma_map_ops pointer. Signed-off-by:
Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Reviewed-by:
Simon Horman <horms+renesas@verge.net.au> Signed-off-by:
Christoph Hellwig <hch@lst.de>
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Yoshihiro Shimoda authored
When the max_segs of a mmc host is smaller than 512, the mmc subsystem tries to use 512 segments if DMA MAP layer can merge the segments, and then the mmc subsystem exposes such information to the block layer by using blk_queue_can_use_dma_map_merging(). Signed-off-by:
Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Reviewed-by:
Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by:
Simon Horman <horms+renesas@verge.net.au> Signed-off-by:
Christoph Hellwig <hch@lst.de>
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Yoshihiro Shimoda authored
This patch adds a helper function whether a queue can merge the segments by the DMA MAP layer (e.g. via IOMMU). Signed-off-by:
Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Reviewed-by:
Christoph Hellwig <hch@lst.de> Reviewed-by: Simon Horman <horms+renesas@verge.net.au Signed-off-by:
Christoph Hellwig <hch@lst.de>
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- 29 Aug, 2019 4 commits
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Christoph Hellwig authored
Based on an email from Paul Burton, quoting section 4.8 "Cacheability and Coherency Attributes and Access Types" of "MIPS Architecture Volume 1: Introduction to the MIPS32 Architecture" (MD00080, revision 6.01). Signed-off-by:
Christoph Hellwig <hch@lst.de> Acked-by:
Paul Burton <paul.burton@mips.com>
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Christoph Hellwig authored
Based on an email from Will Deacon. Signed-off-by:
Christoph Hellwig <hch@lst.de> Acked-by:
Will Deacon <will@kernel.org> Acked-by:
Mark Rutland <mark.rutland@arm.com>
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Christoph Hellwig authored
The memory allocated for the atomic pool needs to have the same mapping attributes that we use for remapping, so use pgprot_dmacoherent instead of open coding it. Also deduct a suitable zone to allocate the memory from based on the presence of the DMA zones. Signed-off-by:
Christoph Hellwig <hch@lst.de>
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Christoph Hellwig authored
arch_dma_mmap_pgprot is used for two things: 1) to override the "normal" uncached page attributes for mapping memory coherent to devices that can't snoop the CPU caches 2) to provide the special DMA_ATTR_WRITE_COMBINE semantics on older arm systems and some mips platforms Replace one with the pgprot_dmacoherent macro that is already provided by arm and much simpler to use, and lift the DMA_ATTR_WRITE_COMBINE handling to common code with an explicit arch opt-in. Signed-off-by:
Christoph Hellwig <hch@lst.de> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # m68k Acked-by: Paul Burton <paul.burton@mips.com> # mips
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- 26 Aug, 2019 2 commits
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Christoph Hellwig authored
Signed-off-by:
Christoph Hellwig <hch@lst.de>
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Christoph Hellwig authored
Signed-off-by:
Christoph Hellwig <hch@lst.de>
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- 25 Aug, 2019 22 commits
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Linus Torvalds authored
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git://github.com/ojeda/linuxLinus Torvalds authored
Pull auxdisplay cleanup from Miguel Ojeda: "Make ht16k33_fb_fix and ht16k33_fb_var constant (Nishka Dasgupta)" * tag 'auxdisplay-for-linus-v5.3-rc7' of git://github.com/ojeda/linux: auxdisplay: ht16k33: Make ht16k33_fb_fix and ht16k33_fb_var constant
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git://git.kernel.org/pub/scm/linux/kernel/git/rw/umlLinus Torvalds authored
Pull UML fix from Richard Weinberger: "Fix time travel mode" * tag 'for-linus-5.3-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: um: fix time travel mode
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git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifsLinus Torvalds authored
Pull UBIFS and JFFS2 fixes from Richard Weinberger: "UBIFS: - Don't block too long in writeback_inodes_sb() - Fix for a possible overrun of the log head - Fix double unlock in orphan_delete() JFFS2: - Remove C++ style from UAPI header and unbreak picky toolchains" * tag 'for-linus-5.3-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs: ubifs: Limit the number of pages in shrink_liability ubifs: Correctly initialize c->min_log_bytes ubifs: Fix double unlock around orphan_delete() jffs2: Remove C++ style comments from uapi header
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull x86 fixes from Thomas Gleixner: "A few fixes for x86: - Fix a boot regression caused by the recent bootparam sanitizing change, which escaped the attention of all people who reviewed that code. - Address a boot problem on machines with broken E820 tables caused by an underflow which ended up placing the trampoline start at physical address 0. - Handle machines which do not advertise a legacy timer of any form, but need calibration of the local APIC timer gracefully by making the calibration routine independent from the tick interrupt. Marked for stable as well as there seems to be quite some new laptops rolled out which expose this. - Clear the RDRAND CPUID bit on AMD family 15h and 16h CPUs which are affected by broken firmware which does not initialize RDRAND correctly after resume. Add a command line parameter to override this for machine which either do not use suspend/resume or have a fixed BIOS. Unfortunately there is no way to detect this on boot, so the only safe decision is to turn it off by default. - Prevent RFLAGS from being clobbers in CALL_NOSPEC on 32bit which caused fast KVM instruction emulation to break. - Explain the Intel CPU model naming convention so that the repeating discussions come to an end" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/retpoline: Don't clobber RFLAGS during CALL_NOSPEC on i386 x86/boot: Fix boot regression caused by bootparam sanitizing x86/CPU/AMD: Clear RDRAND CPUID bit on AMD family 15h/16h x86/boot/compressed/64: Fix boot on machines with broken E820 table x86/apic: Handle missing global clockevent gracefully x86/cpu: Explain Intel model naming convention
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull timekeeping fix from Thomas Gleixner: "A single fix for a regression caused by the generic VDSO implementation where a math overflow causes CLOCK_BOOTTIME to become a random number generator" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: timekeeping/vsyscall: Prevent math overflow in BOOTTIME update
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull scheduler fix from Thomas Gleixner: "Handle the worker management in situations where a task is scheduled out on a PI lock contention correctly and schedule a new worker if possible" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/core: Schedule new worker even if PI-blocked
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull perf fixes from Thomas Gleixner: "Two small fixes for kprobes and perf: - Prevent a deadlock in kprobe_optimizer() causes by reverse lock ordering - Fix a comment typo" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: kprobes: Fix potential deadlock in kprobe_optimizer() perf/x86: Fix typo in comment
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull irq fix from Thomas Gleixner: "A single fix for a imbalanced kobject operation in the irq decriptor code which was unearthed by the new warnings in the kobject code" * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: genirq: Properly pair kobject_del() with kobject_add()
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Linus Torvalds authored
Mergr misc fixes from Andrew Morton: "11 fixes" Mostly VM fixes, one psi polling fix, and one parisc build fix. * emailed patches from Andrew Morton <akpm@linux-foundation.org>: mm/kasan: fix false positive invalid-free reports with CONFIG_KASAN_SW_TAGS=y mm/zsmalloc.c: fix race condition in zs_destroy_pool mm/zsmalloc.c: migration can leave pages in ZS_EMPTY indefinitely mm, page_owner: handle THP splits correctly userfaultfd_release: always remove uffd flags and clear vm_userfaultfd_ctx psi: get poll_work to run when calling poll syscall next time mm: memcontrol: flush percpu vmevents before releasing memcg mm: memcontrol: flush percpu vmstats before releasing memcg parisc: fix compilation errrors mm, page_alloc: move_freepages should not examine struct page of reserved memory mm/z3fold.c: fix race between migration and destruction
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git://git.infradead.org/users/hch/dma-mappingLinus Torvalds authored
Pull dma-mapping fixes from Christoph Hellwig: "Two fixes for regressions in this merge window: - select the Kconfig symbols for the noncoherent dma arch helpers on arm if swiotlb is selected, not just for LPAE to not break then Xen build, that uses swiotlb indirectly through swiotlb-xen - fix the page allocator fallback in dma_alloc_contiguous if the CMA allocation fails" * tag 'dma-mapping-5.3-5' of git://git.infradead.org/users/hch/dma-mapping: dma-direct: fix zone selection after an unaddressable CMA allocation arm: select the dma-noncoherent symbols for all swiotlb builds
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Andrey Ryabinin authored
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: 7f94ffbc ("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>
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Henry Burns authored
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: 48b4800a ("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>
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Henry Burns authored
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: 48b4800a ("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>
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Vlastimil Babka authored
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: a9627bc5 ("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>
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Oleg Nesterov authored
userfaultfd_release() should clear vm_flags/vm_userfaultfd_ctx even if mm->core_state != NULL. Otherwise a page fault can see userfaultfd_missing() == T and use an already freed userfaultfd_ctx. Link: http://lkml.kernel.org/r/20190820160237.GB4983@redhat.com Fixes: 04f5866e ("coredump: fix race condition between mmget_not_zero()/get_task_mm() and core dumping") Signed-off-by:
Oleg Nesterov <oleg@redhat.com> Reported-by:
Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by:
Andrea Arcangeli <aarcange@redhat.com> Tested-by:
Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Peter Xu <peterx@redhat.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Jann Horn <jannh@google.com> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: <stable@vger.kernel.org> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Jason Xing authored
Only when calling the poll syscall the first time can user receive POLLPRI correctly. After that, user always fails to acquire the event signal. Reproduce case: 1. Get the monitor code in Documentation/accounting/psi.txt 2. Run it, and wait for the event triggered. 3. Kill and restart the process. The question is why we can end up with poll_scheduled = 1 but the work not running (which would reset it to 0). And the answer is because the scheduling side sees group->poll_kworker under RCU protection and then schedules it, but here we cancel the work and destroy the worker. The cancel needs to pair with resetting the poll_scheduled flag. Link: http://lkml.kernel.org/r/1566357985-97781-1-git-send-email-joseph.qi@linux.alibaba.comSigned-off-by:
Jason Xing <kerneljasonxing@linux.alibaba.com> Signed-off-by:
Joseph Qi <joseph.qi@linux.alibaba.com> Reviewed-by:
Caspar Zhang <caspar@linux.alibaba.com> Reviewed-by:
Suren Baghdasaryan <surenb@google.com> Acked-by:
Johannes Weiner <hannes@cmpxchg.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@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>
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Roman Gushchin authored
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: 42a30035 ("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>
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Roman Gushchin authored
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: 42a30035 ("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>
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Qian Cai authored
Commit 0cfaee2a ("include/asm-generic/5level-fixup.h: fix variable 'p4d' set but not used") converted a few functions from macros to static inline, which causes parisc to complain, In file included from include/asm-generic/4level-fixup.h:38:0, from arch/parisc/include/asm/pgtable.h:5, from arch/parisc/include/asm/io.h:6, from include/linux/io.h:13, from sound/core/memory.c:9: include/asm-generic/5level-fixup.h:14:18: error: unknown type name 'pgd_t'; did you mean 'pid_t'? #define p4d_t pgd_t ^ include/asm-generic/5level-fixup.h:24:28: note: in expansion of macro 'p4d_t' static inline int p4d_none(p4d_t p4d) ^~~~~ It is because "4level-fixup.h" is included before "asm/page.h" where "pgd_t" is defined. Link: http://lkml.kernel.org/r/20190815205305.1382-1-cai@lca.pw Fixes: 0cfaee2a ("include/asm-generic/5level-fixup.h: fix variable 'p4d' set but not used") Signed-off-by:
Qian Cai <cai@lca.pw> Reported-by:
Guenter Roeck <linux@roeck-us.net> Tested-by:
Guenter Roeck <linux@roeck-us.net> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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David Rientjes authored
After commit 907ec5fc ("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 907ec5fc 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.comSigned-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>
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Henry Burns authored
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.comSigned-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>
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- 24 Aug, 2019 3 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpioLinus Torvalds authored
Pull GPIO fixes from Linus Walleij: "Here is a (hopefully last) set of GPIO fixes for the v5.3 kernel cycle. Two are pretty core: - Fix not reporting open drain/source lines to userspace as "input" - Fix a minor build error found in randconfigs - Fix a chip select quirk on the Freescale SPI - Fix the irqchip initialization semantic order to reflect what it was using the old API" * tag 'gpio-v5.3-4' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: gpio: Fix irqchip initialization order gpio: of: fix Freescale SPI CS quirk handling gpio: Fix build error of function redefinition gpiolib: never report open-drain/source lines as 'input' to user-space
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git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linuxLinus Torvalds authored
Pull Hyper-V fixes from Sasha Levin: - Fix for panics and network failures on PAE guests by Dexuan Cui. - Fix of a memory leak (and related cleanups) in the hyper-v keyboard driver by Dexuan Cui. - Code cleanups for hyper-v clocksource driver during the merge window by Dexuan Cui. - Fix for a false positive warning in the userspace hyper-v KVP store by Vitaly Kuznetsov. * tag 'hyperv-fixes-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: Drivers: hv: vmbus: Fix virt_to_hvpfn() for X86_PAE Tools: hv: kvp: eliminate 'may be used uninitialized' warning Input: hyperv-keyboard: Use in-place iterator API in the channel callback Drivers: hv: vmbus: Remove the unused "tsc_page" from struct hv_context
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git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linuxLinus Torvalds authored
Pull arm64 fixes from Will Deacon: "Two KVM/arm fixes for MMIO emulation and UBSAN. Unusually, we're routing them via the arm64 tree as per Paolo's request on the list: https://lore.kernel.org/kvm/21ae69a2-2546-29d0-bff6-2ea825e3d968@redhat.com/ We don't actually have any other arm64 fixes pending at the moment (touch wood), so I've pulled from Marc, written a merge commit, tagged the result and run it through my build/boot/bisect scripts" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: KVM: arm/arm64: VGIC: Properly initialise private IRQ affinity KVM: arm/arm64: Only skip MMIO insn once
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