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2017-01-26mm/hmm/devmem: dummy HMM device for ZONE_DEVICE memory v2hmm-v17Jérôme Glisse2-1/+117
This introduce a dummy HMM device class so device driver can use it to create hmm_device for the sole purpose of registering device memory. It is usefull to device driver that want to manage multiple physical device memory under same struct device umbrella. Changed since v1: - Improve commit message - Add drvdata parameter to set on struct device Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Signed-off-by: Evgeny Baskakov <ebaskakov@nvidia.com> Signed-off-by: John Hubbard <jhubbard@nvidia.com> Signed-off-by: Mark Hairgrove <mhairgrove@nvidia.com> Signed-off-by: Sherry Cheung <SCheung@nvidia.com> Signed-off-by: Subhash Gutti <sgutti@nvidia.com>
2017-01-26mm/hmm/devmem: device memory hotplug using ZONE_DEVICEJérôme Glisse3-0/+524
This introduce a simple struct and associated helpers for device driver to use when hotpluging un-addressable device memory as ZONE_DEVICE. It will find a unuse physical address range and trigger memory hotplug for it which allocates and initialize struct page for the device memory. Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Signed-off-by: Evgeny Baskakov <ebaskakov@nvidia.com> Signed-off-by: John Hubbard <jhubbard@nvidia.com> Signed-off-by: Mark Hairgrove <mhairgrove@nvidia.com> Signed-off-by: Sherry Cheung <SCheung@nvidia.com> Signed-off-by: Subhash Gutti <sgutti@nvidia.com>
2017-01-26mm/hmm/migrate: support un-addressable ZONE_DEVICE page in migrationJérôme Glisse3-30/+153
Allow to unmap and restore special swap entry of un-addressable ZONE_DEVICE memory. Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
2017-01-26mm/hmm/mirror: device page fault handlerJérôme Glisse2-28/+267
This handle page fault on behalf of device driver, unlike handle_mm_fault() it does not trigger migration back to system memory for device memory. Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Signed-off-by: Evgeny Baskakov <ebaskakov@nvidia.com> Signed-off-by: John Hubbard <jhubbard@nvidia.com> Signed-off-by: Mark Hairgrove <mhairgrove@nvidia.com> Signed-off-by: Sherry Cheung <SCheung@nvidia.com> Signed-off-by: Subhash Gutti <sgutti@nvidia.com>
2017-01-26mm/hmm/mirror: helper to snapshot CPU page tableJérôme Glisse2-2/+311
This does not use existing page table walker because we want to share same code for our page fault handler. Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Signed-off-by: Evgeny Baskakov <ebaskakov@nvidia.com> Signed-off-by: John Hubbard <jhubbard@nvidia.com> Signed-off-by: Mark Hairgrove <mhairgrove@nvidia.com> Signed-off-by: Sherry Cheung <SCheung@nvidia.com> Signed-off-by: Subhash Gutti <sgutti@nvidia.com>
2017-01-26mm/hmm/mirror: mirror process address space on device with HMM helpersJérôme Glisse3-0/+301
This is a heterogeneous memory management (HMM) process address space mirroring. In a nutshell this provide an API to mirror process address space on a device. This boils down to keeping CPU and device page table synchronize (we assume that both device and CPU are cache coherent like PCIe device can be). This patch provide a simple API for device driver to achieve address space mirroring thus avoiding each device driver to grow its own CPU page table walker and its own CPU page table synchronization mechanism. This is useful for NVidia GPU >= Pascal, Mellanox IB >= mlx5 and more hardware in the future. Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Signed-off-by: Evgeny Baskakov <ebaskakov@nvidia.com> Signed-off-by: John Hubbard <jhubbard@nvidia.com> Signed-off-by: Mark Hairgrove <mhairgrove@nvidia.com> Signed-off-by: Sherry Cheung <SCheung@nvidia.com> Signed-off-by: Subhash Gutti <sgutti@nvidia.com>
2017-01-26mm/hmm: heterogeneous memory management (HMM for short)Jérôme Glisse7-0/+251
HMM provides 3 separate functionality : - Mirroring: synchronize CPU page table and device page table - Device memory: allocating struct page for device memory - Migration: migrating regular memory to device memory This patch introduces some common helpers and definitions to all of those 3 functionality. Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Signed-off-by: Evgeny Baskakov <ebaskakov@nvidia.com> Signed-off-by: John Hubbard <jhubbard@nvidia.com> Signed-off-by: Mark Hairgrove <mhairgrove@nvidia.com> Signed-off-by: Sherry Cheung <SCheung@nvidia.com> Signed-off-by: Subhash Gutti <sgutti@nvidia.com>
2017-01-26mm/migrate: migrate_vma() unmap page from vma while collecting pagesJérôme Glisse1-15/+93
Common case for migration of virtual address range is page are map only once inside the vma in which migration is taking place. Because we already walk the CPU page table for that range we can directly do the unmap there and setup special migration swap entry. Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Signed-off-by: Evgeny Baskakov <ebaskakov@nvidia.com> Signed-off-by: John Hubbard <jhubbard@nvidia.com> Signed-off-by: Mark Hairgrove <mhairgrove@nvidia.com> Signed-off-by: Sherry Cheung <SCheung@nvidia.com> Signed-off-by: Subhash Gutti <sgutti@nvidia.com>
2017-01-26mm/migrate: new memory migration helper for use with device memory v3Jérôme Glisse2-0/+523
This patch add a new memory migration helpers, which migrate memory backing a range of virtual address of a process to different memory (which can be allocated through special allocator). It differs from numa migration by working on a range of virtual address and thus by doing migration in chunk that can be large enough to use DMA engine or special copy offloading engine. Expected users are any one with heterogeneous memory where different memory have different characteristics (latency, bandwidth, ...). As an example IBM platform with CAPI bus can make use of this feature to migrate between regular memory and CAPI device memory. New CPU architecture with a pool of high performance memory not manage as cache but presented as regular memory (while being faster and with lower latency than DDR) will also be prime user of this patch. Migration to private device memory will be usefull for device that have large pool of such like GPU, NVidia plans to use HMM for that. Changed since v2: - droped HMM prefix and HMM specific code Changed since v1: - typos fix - split early unmap optimization for page with single mapping Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Signed-off-by: Evgeny Baskakov <ebaskakov@nvidia.com> Signed-off-by: John Hubbard <jhubbard@nvidia.com> Signed-off-by: Mark Hairgrove <mhairgrove@nvidia.com> Signed-off-by: Sherry Cheung <SCheung@nvidia.com> Signed-off-by: Subhash Gutti <sgutti@nvidia.com>
2017-01-24mm/migrate: add new boolean copy flag to migratepage() callbackJérôme Glisse13-44/+106
Allow migration without copy in case destination page already have source page content. This is usefull for new dma capable migration where use device dma engine to copy pages. This feature need carefull audit of filesystem code to make sure that no one can write to the source page while it is unmapped and locked. It should be safe for most filesystem but as precaution return error until support for device migration is added to them. Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
2017-01-19mm/ZONE_DEVICE/x86: add support for un-addressable device memoryJérôme Glisse1-4/+18
It does not need much, just skip populating kernel linear mapping for range of un-addressable device memory (it is pick so that there is no physical memory resource overlapping it). All the logic is in share mm code. Only support x86-64 as this feature doesn't make much sense with constrained virtual address space of 32bits architecture. Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com>
2017-01-19mm/ZONE_DEVICE/unaddressable: add support for un-addressable device memory v3Jérôme Glisse11-9/+235
This add support for un-addressable device memory. Such memory is hotpluged only so we can have struct page but we should never map them as such memory can not be accessed by CPU. For that reason it uses a special swap entry for CPU page table entry. This patch implement all the logic from special swap type to handling CPU page fault through a callback specified in the ZONE_DEVICE pgmap struct. Architecture that wish to support un-addressable device memory should make sure to never populate the kernel linar mapping for the physical range. This feature potentially breaks memory hotplug unless every driver using it magically predicts the future addresses of where memory will be hotplugged. Changed since v2: - Do not change devm_memremap_pages() Changed since v1: - Add unaddressable memory resource descriptor enum - Explain why memory hotplug can fail because of un-addressable memory Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
2017-01-19mm/ZONE_DEVICE/free-page: callback when page is freed v2Jérôme Glisse2-1/+15
When a ZONE_DEVICE page refcount reach 1 it means it is free and nobody is holding a reference on it (only device to which the memory belong do). Add a callback and call it when that happen so device driver can implement their own free page management. Changed since v1: - Do not update devm_memremap_pages() to take extra argument Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
2017-01-19mm/memory/hotplug: convert device bool to int to allow for more flags v2Jérôme Glisse11-25/+151
When hotpluging memory we want more informations on the type of memory and its properties. Replace the device boolean flag by an int and define a set of flags. New property for device memory is an opt-in flag to allow page migration from and to a ZONE_DEVICE. Existing user of ZONE_DEVICE are not expecting page migration to work for their pages. New changes to page migration i changing that and we now need a flag to explicitly opt-in page migration. Changes since v1: - Improved commit message - Improved define name - Improved comments - Typos Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Rich Felker <dalias@libc.org> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com>
2016-12-20reimplement-idr-and-ida-using-the-radix-tree-support-storing-null-in-the-idr ↵Andrew Morton1-4/+2
-checkpatch-fixes WARNING: braces {} are not necessary for single statement blocks #143: FILE: tools/testing/radix-tree/idr-test.c:88: + for (i = 0; i < 10; i++) { + assert(idr_alloc(&idr, NULL, 0, 0, GFP_KERNEL) == i); + } WARNING: braces {} are not necessary for single statement blocks #167: FILE: tools/testing/radix-tree/idr-test.c:112: + for (i = 1; i < 10; i++) { + assert(idr_alloc(&idr, NULL, 1, 0, GFP_KERNEL) == i); + } total: 0 errors, 2 warnings, 159 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. ./patches/reimplement-idr-and-ida-using-the-radix-tree-support-storing-null-in-the-idr.patch has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: Matthew Wilcox <mawilcox@microsoft.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-20idr: support storing NULL in the IDRMatthew Wilcox3-14/+65
The radix tree interprets storing NULL as a deleted entry. Several users of the IDR API use NULL as a temporary placeholder, or intentionally convert entries between NULL and non-NULL pointers to keep IDs reserved but not necessarily pointing to a valid entry at any given moment. Adapt the radix tree to cope with NULL pointers when being used as an IDR. Link: http://lkml.kernel.org/r/1481931156-23469-1-git-send-email-mawilcox@linuxonhyperv.com Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-20fs: add i_blocksize()Fabian Frederick26-50/+55
Replace all 1 << inode->i_blkbits and (1 << inode->i_blkbits) in fs branch This patch also fixes multiple checkpatch warnings: WARNING: Prefer 'unsigned int' to bare use of 'unsigned' Thanks to Andrew Morton for suggesting more appropriate function instead of macro. Link: http://lkml.kernel.org/r/1481319905-10126-1-git-send-email-fabf@skynet.be Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-20mm, page_alloc: avoid page_to_pfn() when merging buddiesVlastimil Babka2-6/+6
On architectures that allow memory holes, page_is_buddy() has to perform page_to_pfn() to check for the memory hole. After the previous patch, we have the pfn already available in __free_one_page(), which is the only caller of page_is_buddy(), so move the check there and avoid page_to_pfn(). Link: http://lkml.kernel.org/r/20161216120009.20064-2-vbabka@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Mel Gorman <mgorman@techsingularity.net> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-20mm, page_alloc: don't convert pfn to idx when mergingVlastimil Babka3-23/+20
In __free_one_page() we do the buddy merging arithmetics on "page/buddy index", which is just the lower MAX_ORDER bits of pfn. The operations we do that affect the higher bits are bitwise AND and subtraction (in that order), where the final result will be the same with the higher bits left unmasked, as long as these bits are equal for both buddies - which must be true by the definition of a buddy. We can therefore use pfn's directly instead of "index" and skip the zeroing of >MAX_ORDER bits. This can help a bit by itself, although compiler might be smart enough already. It also helps the next patch to avoid page_to_pfn() for memory hole checks. Link: http://lkml.kernel.org/r/20161216120009.20064-1-vbabka@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Mel Gorman <mgorman@techsingularity.net> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-20mm-throttle-show_mem-from-warn_alloc-fixAndrew Morton1-6/+3
reduce scope of the ratelimit_states Cc: Michal Hocko <mhocko@suse.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-20mm: throttle show_mem() from warn_alloc()Michal Hocko1-7/+17
Tetsuo has been stressing OOM killer path with many parallel allocation requests when he has noticed that it is not all that hard to swamp kernel logs with warn_alloc messages caused by allocation stalls. Even though the allocation stall message is triggered only once in 10s there might be many different tasks hitting it roughly around the same time. A big part of the output is show_mem() which can generate a lot of output even on a small machines. There is no reason to show the state of memory counter for each allocation stall, especially when multiple of them are reported in a short time period. Chances are that not much has changed since the last report. This patch simply rate limits show_mem called from warn_alloc to only dump something once per second. This should be enough to give us a clue why an allocation might be stalling while burst of warnings will not swamp log with too much data. While we are at it, extract all the show_mem related handling (filters) into a separate function warn_alloc_show_mem. This will make the code cleaner and as a bonus point we can distinguish which part of warn_alloc got throttled due to rate limiting as ___ratelimit dumps the caller. Link: http://lkml.kernel.org/r/20161215101510.9030-1-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-20tmpfs: change shmem_mapping() to test shmem_aopsHugh Dickins1-4/+1
Callers of shmem_mapping() are interested in whether the mapping is swap backed - except for uprobes, which is interested in whether it should use shmem_read_mapping_page(). All these callers are better served by a shmem_mapping() which checks for shmem_aops, than the current version which goes through several indirections to find where the inode lives - and has the surprising effect that a private mmap of /dev/zero satisfies both vma_is_anonymous() and shmem_mapping(), when that device node is on devtmpfs. I don't think anything in the tree suffers from that surprise, but it caught me out, and is better fixed. Link: http://lkml.kernel.org/r/alpine.LSU.2.11.1612052148530.13021@eggly.anvils Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-20mm/thp/pagecache/collapse: free the pte page table on collapse for thp page ↵Aneesh Kumar K.V1-19/+2
cache. With THP page cache, when trying to build a huge page from regular pte pages, we just clear the pmd entry. We will take another fault and at that point we will find the huge page in the radix tree, thereby using the huge page to complete the page fault The second fault path will allocate the needed pgtable_t page for archs like ppc64. So no need to deposit the same in collapse path. Depositing them in the collapse path resulting in a pgtable_t memory leak also giving errors like "[ 2362.021762] BUG: non-zero nr_ptes on freeing mm: 3" Fixes: 953c66c2b22a304d ("mm: THP page cache support for ppc64") Link: http://lkml.kernel.org/r/20161212163428.6780-2-aneesh.kumar@linux.vnet.ibm.com Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-20mm/thp/pagecache: only withdraw page table after a successful depositAneesh Kumar K.V1-7/+0
The current code wrongly called withdraw in the error path. But we haven't depoisted the page table yet in the only error path in that function. So for now remove that withdraw completely. If we take that "out:" branch, we should have vmf->prealloc_pte already pointing to the allocated page table. Fixes: 953c66c2b22a304d ("mm: THP page cache support for ppc64") Link: http://lkml.kernel.org/r/20161212163428.6780-1-aneesh.kumar@linux.vnet.ibm.com Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Reported-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-20mm, page_alloc: fix incorrect zone_statistics dataJia He1-0/+3
In commit b9f00e147f27 ("mm, page_alloc: reduce branches in zone_statistics"), it reconstructed codes to reduce the branch miss rate. Compared with the original logic, it assumed if !(flag & __GFP_OTHER_NODE) z->node would not be equal to preferred_zone->node. That seems to be incorrect. Fixes: commit b9f00e147f27 ("mm, page_alloc: reduce branches in zone_statistics") Link: http://lkml.kernel.org/r/1481522347-20393-2-git-send-email-hejianet@gmail.com Signed-off-by: Jia He <hejianet@gmail.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Taku Izumi <izumi.taku@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-20ratelimit: fix WARN_ON_RATELIMIT return valueJiri Slaby1-2/+5
The macro is to be used similarly as WARN_ON as: if (WARN_ON_RATELIMIT(condition, state)) do_something(); One would expect only 'condition' to affect the 'if', but WARN_ON_RATELIMIT does internally only: WARN_ON((condition) && __ratelimit(state)) So the 'if' is affected by the ratelimiting state too. Fix this by returning 'condition' in any case. Note that nobody uses WARN_ON_RATELIMIT yet, so there is nothing to worry about. But I was about to use it and was a bit surprised. Link: http://lkml.kernel.org/r/20161215093224.23126-1-jslaby@suse.cz Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-20mm: fadvise: avoid expensive remote LRU cache draining after FADV_DONTNEEDJohannes Weiner1-1/+14
When FADV_DONTNEED cannot drop all pages in the range, it observes that some pages might still be on per-cpu LRU caches after recent instantiation and so initiates remote calls to all CPUs to flush their local caches. However, in most cases, the fadvise happens from the same context that instantiated the pages, and any pre-LRU pages in the specified range are most likely sitting on the local CPU's LRU cache, and so in many cases this results in unnecessary remote calls, which, in a loaded system, can hold up the fadvise() call significantly. [ I didn't record it in the extreme case we observed at Facebook, unfortunately. We had a slow-to-respond system and noticed it lru_add_drain_all() leading the profile during fadvise calls. This patch came out of thinking about the code and how we commonly call FADV_DONTNEED. FWIW, I wrote a silly directory tree walker/searcher that recurses through /usr to read and FADV_DONTNEED each file it finds. On a 2 socket 40 ht machine, over 1% is spent in lru_add_drain_all(). With the patch, that cost is gone; the local drain cost shows at 0.09%. ] Try to avoid the remote call by flushing the local LRU cache before even attempting to invalidate anything. It's a cheap operation, and the local LRU cache is the most likely to hold any pre-LRU pages in the specified fadvise range. Link: http://lkml.kernel.org/r/20161214210017.GA1465@cmpxchg.org Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Mel Gorman <mgorman@suse.de> Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15kcov: make kcov work properly with KASLR enabledAlexander Popov1-1/+7
Subtract KASLR offset from the kernel addresses reported by kcov. Tested on x86_64 and AArch64 (Hikey LeMaker). Link: http://lkml.kernel.org/r/1481417456-28826-3-git-send-email-alex.popov@linux.com Signed-off-by: Alexander Popov <alex.popov@linux.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Rob Herring <robh@kernel.org> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Jon Masters <jcm@redhat.com> Cc: David Daney <david.daney@cavium.com> Cc: Ganapatrao Kulkarni <gkulkarni@caviumnetworks.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Nicolai Stange <nicstange@gmail.com> Cc: James Morse <james.morse@arm.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Alexander Popov <alex.popov@linux.com> Cc: syzkaller <syzkaller@googlegroups.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15arm64: setup: introduce kaslr_offset()Alexander Popov3-6/+25
Introduce kaslr_offset() similar to x86_64 to fix kcov. Link: http://lkml.kernel.org/r/1481417456-28826-2-git-send-email-alex.popov@linux.com Signed-off-by: Alexander Popov <alex.popov@linux.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Rob Herring <robh@kernel.org> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Jon Masters <jcm@redhat.com> Cc: David Daney <david.daney@cavium.com> Cc: Ganapatrao Kulkarni <gkulkarni@caviumnetworks.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Nicolai Stange <nicstange@gmail.com> Cc: James Morse <james.morse@arm.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Alexander Popov <alex.popov@linux.com> Cc: syzkaller <syzkaller@googlegroups.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15Reimplement IDR and IDA using the radix treeMatthew Wilcox15-1087/+815
The IDR is very similar to the radix tree. It has some functionality that the radix tree did not have (alloc next free, cyclic allocation, a callback-based for_each, destroy tree), which is readily implementable on top of the radix tree. A few small changes were needed in order to use a tag to represent nodes with free space below them. The IDA is reimplemented as a client of the newly enhanced radix tree. As in the current implementation, it uses a bitmap at the last level of the tree. Link: http://lkml.kernel.org/r/1481667692-14500-6-git-send-email-mawilcox@linuxonhyperv.com Signed-off-by: Matthew Wilcox <willy@infradead.org> Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Tested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15radix tree test suite: delete unused rcupdate.cMatthew Wilcox1-86/+0
This file was used to implement call_rcu() before liburcu implemented that function. It hasn't even been compiled since before the test suite was added to the kernel. Remove it to reduce confusion. Link: http://lkml.kernel.org/r/1481667692-14500-5-git-send-email-mawilcox@linuxonhyperv.com Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15radix tree test suite: add new tag checkMatthew Wilcox1-0/+3
We have a check that setting a tag on a single entry at root succeeds, but we were missing a check that clearing a tag on that same entry also succeeds. Link: http://lkml.kernel.org/r/1481667692-14500-4-git-send-email-mawilcox@linuxonhyperv.com Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15radix-tree: ensure counts are initialisedMatthew Wilcox2-25/+61
radix_tree_join() was freeing nodes with a non-zero ->exceptional count, and radix_tree_split() wasn't zeroing ->exceptional when it allocated the new node. Fix this by making all callers of radix_tree_node_alloc() pass in the new counts (and some other always-initialised fields), which will prevent the problem recurring if in future we decide to do something similar. Link: http://lkml.kernel.org/r/1481667692-14500-3-git-send-email-mawilcox@linuxonhyperv.com Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15radix tree test suite: cache recently freed objectsMatthew Wilcox2-12/+41
The kmem_cache_alloc implementation simply allocates new memory from malloc() and calls the ctor, which zeroes out the entire object. This means it cannot spot bugs where the object isn't properly reinitialised before being freed. Add a small (11 objects) cache before freeing objects back to malloc. This is enough to let us write a test to catch it, although the memory allocator is now aware of the structure of the radix tree node, since it chains free objects through ->private_data (like the percpu cache does). Link: http://lkml.kernel.org/r/1481667692-14500-2-git-send-email-mawilcox@linuxonhyperv.com Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15drivers/net/wireless/intel/iwlwifi/dvm/calib.c: simplfy min() expressionAndrew Morton1-2/+1
This cast is no longer needed. Cc: Johannes Berg <johannes.berg@intel.com> Cc: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Cc: Intel Linux Wireless <linuxwifi@intel.com> Cc: Kalle Valo <kvalo@codeaurora.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15posix-timers: give lazy compilers some help optimizing code awayNicolas Pitre1-1/+2
The OpenRISC compiler (so far) fails to optimize away a large portion of code containing a reference to posix_timer_event in alarmtimer.c when CONFIG_POSIX_TIMERS is unset. Let's give it a direct clue to let the build succeed. This fixes [linux-next:master 6682/7183] alarmtimer.c:undefined reference to `posix_timer_event' reported by kbuild test robot. Signed-off-by: Nicolas Pitre <nico@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15ipc/shm.c: coding style fixesShailesh Pandey1-3/+10
This patch fixes below warnings WARNING: Missing a blank line after declarations WARNING: Block comments use a trailing */ on a separate line ERROR: spaces required around that '=' (ctx:WxV) Above warnings were reported by checkpatch.pl Link: http://lkml.kernel.org/r/1478604980-18062-1-git-send-email-p.shailesh@samsung.com Signed-off-by: Shailesh Pandey <p.shailesh@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15ipc: msg, make msgrcv work with LONG_MINJiri Slaby1-1/+4
When LONG_MIN is passed to msgrcv, one would expect to recieve any message. But convert_mode does *msgtyp = -*msgtyp and -LONG_MIN is undefined. In particular, with my gcc -LONG_MIN produces -LONG_MIN again. So handle this case properly by assigning LONG_MAX to *msgtyp if LONG_MIN was specified as msgtyp to msgrcv. This code: long msg[] = { 100, 200 }; int m = msgget(IPC_PRIVATE, IPC_CREAT | 0644); msgsnd(m, &msg, sizeof(msg), 0); msgrcv(m, &msg, sizeof(msg), LONG_MIN, 0); produces currently nothing: msgget(IPC_PRIVATE, IPC_CREAT|0644) = 65538 msgsnd(65538, {100, "\310\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"}, 16, 0) = 0 msgrcv(65538, ... Except a UBSAN warning: UBSAN: Undefined behaviour in ipc/msg.c:745:13 negation of -9223372036854775808 cannot be represented in type 'long int': With the patch, I see what I expect: msgget(IPC_PRIVATE, IPC_CREAT|0644) = 0 msgsnd(0, {100, "\310\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"}, 16, 0) = 0 msgrcv(0, {100, "\310\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"}, 16, -9223372036854775808, 0) = 16 Link: http://lkml.kernel.org/r/20161024082633.10148-1-jslaby@suse.cz Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Manfred Spraul <manfred@colorfullife.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15initramfs: allow again choice of the embedded initram compression algorithmFrancisco Blas Izquierdo Riera (klondike)1-0/+117
Choosing the appropriate compression option when using an embedded initramfs can result in significant size differences in the resulting data. This is caused by avoiding double compression of the initramfs contents. For example on my tests, choosing CONFIG_INITRAMFS_COMPRESSION_NONE when compressing the kernel using XZ) results in up to 500KiB differences (9MiB to 8.5MiB) in the kernel size as the dictionary will not get polluted with uncomprensible data and may reuse kernel data too. Despite embedding an uncompressed initramfs, a user may want to allow for a compressed extra initramfs to be passed using the rd system, for example to boot a recovery system. 9ba4bcb645898d ("initramfs: read CONFIG_RD_ variables for initramfs compression") broke that behavior by making the choice based on CONFIG_RD_* instead of adding CONFIG_INITRAMFS_COMPRESSION_LZ4. Saddly, CONFIG_RD_* is also used to choose the supported RD compression algorithms by the kernel and a user may want to support more than one. This patch also reverses 3e4e0f0a875 ("initramfs: remove "compression mode" choice") restoring back the "compression mode" choice and includes the CONFIG_INITRAMFS_COMPRESSION_LZ4 option which was never added. As a result the following options are added or readed affecting the embedded initramfs compression: INITRAMFS_COMPRESSION_NONE Do no compression INITRAMFS_COMPRESSION_GZIP Compress using gzip INITRAMFS_COMPRESSION_BZIP2 Compress using bzip2 INITRAMFS_COMPRESSION_LZMA Compress using lzma INITRAMFS_COMPRESSION_XZ Compress using xz INITRAMFS_COMPRESSION_LZO Compress using lzo INITRAMFS_COMPRESSION_LZ4 Compress using lz4 These depend on the corresponding CONFIG_RD_* option being set (except NONE which has no dependencies). This patch depends on the previous one (the previous version didn't) to simplify the way in which the algorithm is chosen and keep backwards compatibility with the behaviour introduced by 9ba4bcb645898 ("initramfs: read CONFIG_RD_ variables for initramfs compression"). Link: http://lkml.kernel.org/r/57EAD77B.7090607@klondike.es Signed-off-by: Francisco Blas Izquierdo Riera (klondike) <klondike@klondike.es> Cc: P J P <ppandit@redhat.com> Cc: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15initramfs: select builtin initram compression algorithm on KConfig instead ↵Francisco Blas Izquierdo Riera (klondike)2-19/+11
of Makefile Move the current builtin initram compression algorithm selection from the Makefile into the INITRAMFS_COMPRESSION variable. This makes deciding algorithm precedence easier and would allow for overrides if new algorithms want to be tested. Link: http://lkml.kernel.org/r/57EAD769.1090401@klondike.es Signed-off-by: Francisco Blas Izquierdo Riera (klondike) <klondike@klondike.es> Cc: P J P <ppandit@redhat.com> Cc: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15kernel/debug/debug_core.c: more properly delay for secondary CPUsDouglas Anderson1-2/+2
We've got a delay loop waiting for secondary CPUs. That loop uses loops_per_jiffy. However, loops_per_jiffy doesn't actually mean how many tight loops make up a jiffy on all architectures. It is quite common to see things like this in the boot log: Calibrating delay loop (skipped), value calculated using timer frequency.. 48.00 BogoMIPS (lpj=24000) In my case I was seeing lots of cases where other CPUs timed out entering the debugger only to print their stack crawls shortly after the kdb> prompt was written. Elsewhere in kgdb we already use udelay(), so that should be safe enough to use to implement our timeout. We'll delay 1 ms for 1000 times, which should give us a full second of delay (just like the old code wanted) but allow us to notice that we're done every 1 ms. [akpm@linux-foundation.org: simplifications, per Daniel] Link: http://lkml.kernel.org/r/1477091361-2039-1-git-send-email-dianders@chromium.org Signed-off-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Brian Norris <briannorris@chromium.org> Cc: <stable@vger.kernel.org> [4.0+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15kcov: add more missing includesKefeng Wang1-0/+5
It is fragile that some definitions acquired via transitive dependencies, as shown in below: atomic_* (<linux/atomic.h>) ENOMEM/EN* (<linux/errno.h>) EXPORT_SYMBOL (<linux/export.h>) device_initcall (<linux/init.h>) preempt_* (<linux/preempt.h>) Include them to prevent possible issues. Link: http://lkml.kernel.org/r/1481163221-40170-1-git-send-email-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Suggested-by: Mark Rutland <mark.rutland@arm.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15Kconfig: lib/Kconfig.ubsan fix reference to ubsan documentationAndreas Platschek1-1/+2
Documenation/ubsan.txt was moved to Documentation/dev-tools/ubsan.rst, this fixes the reference. Link: http://lkml.kernel.org/r/1476698152-29340-3-git-send-email-andreas.platschek@opentech.at Signed-off-by: Andreas Platschek <andreas.platschek@opentech.at> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15Kconfig: lib/Kconfig.debug: fix references to DocumenationAndreas Platschek1-4/+4
Documentation on development tools was moved to Documentation/devl-tools and sphinxified (renamed from .txt to .rst). References in lib/Kconfig.debug need to be updated to the new location. Link: http://lkml.kernel.org/r/1476698152-29340-2-git-send-email-andreas.platschek@opentech.at Signed-off-by: Andreas Platschek <andreas.platschek@opentech.at> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15relay: check array offset before using itDan Carpenter1-2/+2
Smatch complains that we started using the array offset before we checked that it was valid. Fixes: 017c59c042d0 ('relay: Use per CPU constructs for the relay channel buffer pointers') Link: http://lkml.kernel.org/r/20161013084947.GC16198@mwanda Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15igb: update code to better handle incrementing page countAlexander Duyck2-8/+23
Update the driver code so that we do bulk updates of the page reference count instead of just incrementing it by one reference at a time. The advantage to doing this is that we cut down on atomic operations and this in turn should give us a slight improvement in cycles per packet. In addition if we eventually move this over to using build_skb the gains will be more noticeable. Link: http://lkml.kernel.org/r/20161110113616.76501.17072.stgit@ahduyck-blue-test.jf.intel.com Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: David Howells <dhowells@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no> Cc: Helge Deller <deller@gmx.de> Cc: James Hogan <james.hogan@imgtec.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Keguang Zhang <keguang.zhang@gmail.com> Cc: Ley Foon Tan <lftan@altera.com> Cc: Mark Salter <msalter@redhat.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Rich Felker <dalias@libc.org> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Steven Miao <realmz6@gmail.com> Cc: Tobias Klauser <tklauser@distanz.ch> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15igb: update driver to make use of DMA_ATTR_SKIP_CPU_SYNCAlexander Duyck1-20/+33
The ARM architecture provides a mechanism for deferring cache line invalidation in the case of map/unmap. This patch makes use of this mechanism to avoid unnecessary synchronization. A secondary effect of this change is that the portion of the page that has been synchronized for use by the CPU should be writable and could be passed up the stack (at least on ARM). The last bit that occurred to me is that on architectures where the sync_for_cpu call invalidates cache lines we were prefetching and then invalidating the first 128 bytes of the packet. To avoid that I have moved the sync up to before we perform the prefetch and allocate the skbuff so that we can actually make use of it. Link: http://lkml.kernel.org/r/20161110113611.76501.98897.stgit@ahduyck-blue-test.jf.intel.com Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: David Howells <dhowells@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no> Cc: Helge Deller <deller@gmx.de> Cc: James Hogan <james.hogan@imgtec.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Keguang Zhang <keguang.zhang@gmail.com> Cc: Ley Foon Tan <lftan@altera.com> Cc: Mark Salter <msalter@redhat.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Rich Felker <dalias@libc.org> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Steven Miao <realmz6@gmail.com> Cc: Tobias Klauser <tklauser@distanz.ch> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15mm: add support for releasing multiple instances of a pageAlexander Duyck2-0/+16
Add a function that allows us to batch free a page that has multiple references outstanding. Specifically this function can be used to drop a page being used in the page frag alloc cache. With this drivers can make use of functionality similar to the page frag alloc cache without having to do any workarounds for the fact that there is no function that frees multiple references. Link: http://lkml.kernel.org/r/20161110113606.76501.70752.stgit@ahduyck-blue-test.jf.intel.com Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: David Howells <dhowells@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no> Cc: Helge Deller <deller@gmx.de> Cc: James Hogan <james.hogan@imgtec.com> Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Keguang Zhang <keguang.zhang@gmail.com> Cc: Ley Foon Tan <lftan@altera.com> Cc: Mark Salter <msalter@redhat.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Rich Felker <dalias@libc.org> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Steven Miao <realmz6@gmail.com> Cc: Tobias Klauser <tklauser@distanz.ch> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15dma: add calls for dma_map_page_attrs and dma_unmap_page_attrsAlexander Duyck1-7/+13
Add support for mapping and unmapping a page with attributes. The primary use for this is currently to allow for us to pass the DMA_ATTR_SKIP_CPU_SYNC attribute when mapping and unmapping a page. On some architectures such as ARM the synchronization has significant overhead and if we are already taking care of the sync_for_cpu and sync_for_device from the driver there isn't much need to handle this in the map/unmap calls as well. Link: http://lkml.kernel.org/r/20161110113601.76501.46095.stgit@ahduyck-blue-test.jf.intel.com Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-12-15arch/xtensa: add option to skip DMA sync as a part of mappingAlexander Duyck1-2/+5
This change allows us to pass DMA_ATTR_SKIP_CPU_SYNC which allows us to avoid invoking cache line invalidation if the driver will just handle it via a sync_for_cpu or sync_for_device call. Link: http://lkml.kernel.org/r/20161110113555.76501.52536.stgit@ahduyck-blue-test.jf.intel.com Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>