- 31 Jan, 2020 40 commits
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David Rientjes authored
When a process cannot be oom reaped, for whatever reason, currently the list of locks that are held is currently dumped to the kernel log. Much more interesting is the stack trace of the victim that cannot be reaped. If the stack trace is dumped, we have the ability to find related occurrences in the same kernel code and hopefully solve the issue that is making it wedged. Dump the stack trace when a process fails to be oom reaped. Link: http://lkml.kernel.org/r/alpine.DEB.2.21.2001141519280.200484@chino.kir.corp.google.comSigned-off-by:
David Rientjes <rientjes@google.com> Acked-by:
Michal Hocko <mhocko@suse.com> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Anshuman Khandual authored
Replace open function name strings with %s (__func__) in all remaining memblock_dbg() call sites. Link: http://lkml.kernel.org/r/1578285510-28261-1-git-send-email-anshuman.khandual@arm.comSigned-off-by:
Anshuman Khandual <anshuman.khandual@arm.com> Reviewed-by:
Mike Rapoport <rppt@linux.ibm.com> Signed-off-by:
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Anshuman Khandual authored
On the s390 platform memblock.physmem array is being built by directly calling into memblock_add_range() which is a low level function not intended to be used outside of memblock. Hence lets conditionally add helper functions for physmem array when HAVE_MEMBLOCK_PHYS_MAP is enabled. Also use MAX_NUMNODES instead of 0 as node ID similar to memblock_add() and memblock_reserve(). Make memblock_add_range() a static function as it is no longer getting used outside of memblock. Link: http://lkml.kernel.org/r/1578283835-21969-1-git-send-email-anshuman.khandual@arm.comSigned-off-by:
Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Collin Walling <walling@linux.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Philipp Rudo <prudo@linux.ibm.com> Signed-off-by:
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Daniel Wagner authored
The sysfs file name for enabling sanity checking is called 'sanity_checks' and not 'sanity'. The name of the file has never changed since the introduction of the slub allocator. Obviously, most people turn the checks on via the command line option and not during runtime using slabinfo. Link: http://lkml.kernel.org/r/20200116131642.642-1-dwagner@suse.deSigned-off-by:
Daniel Wagner <dwagner@suse.de> Reviewed-by:
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Alex Shi authored
Commit 1b2ffb78 ("[PATCH] Zone reclaim: Allow modification of zone reclaim behavior")' defined RECLAIM_OFF/RECLAIM_ZONE, but never use them, so better to remove them. [dwagner@suse.de: fix sanity checks enabling] Link: http://lkml.kernel.org/r/20200116131642.642-1-dwagner@suse.de [akpm@linux-foundation.org: renumber the bits for neatness] Link: http://lkml.kernel.org/r/1579005573-58923-1-git-send-email-alex.shi@linux.alibaba.comSigned-off-by:
Alex Shi <alex.shi@linux.alibaba.com> Signed-off-by:
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Alex Shi authored
This macro was never used in git history. So better to remove. Link: http://lkml.kernel.org/r/1579006500-127143-1-git-send-email-alex.shi@linux.alibaba.comSigned-off-by:
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Liu Song authored
The return value of shrink_node is not used, so remove unnecessary operations. Link: http://lkml.kernel.org/r/20191128143524.3223-1-fishland@aliyun.comSigned-off-by:
Liu Song <liu.song11@zte.com.cn> Reviewed-by:
David Hildenbrand <david@redhat.com> Signed-off-by:
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David Hildenbrand authored
Now that the memory isolate notifier is gone, the parameter is always 0. Drop it and cleanup has_unmovable_pages(). Link: http://lkml.kernel.org/r/20191114131911.11783-3-david@redhat.comSigned-off-by:
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David Hildenbrand authored
Luckily, we have no users left, so we can get rid of it. Cleanup set_migratetype_isolate() a little bit. Link: http://lkml.kernel.org/r/20191114131911.11783-2-david@redhat.comSigned-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by:
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Kirill A. Shutemov authored
memmap_init_zone() can be called on the ranges with holes during the boot. It will skip any non-valid PFNs one-by-one. It works fine as long as holes are not too big. But huge holes in the memory map causes a problem. It takes over 20 seconds to walk 32TiB hole. x86-64 with 5-level paging allows for much larger holes in the memory map which would practically hang the system. Deferred struct page init doesn't help here. It only works on the present ranges. Skipping non-present sections would fix the issue. Link: http://lkml.kernel.org/r/20191230093828.24613-1-kirill.shutemov@linux.intel.comSigned-off-by:
Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by:
Baoquan He <bhe@redhat.com> Acked-by:
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Andy Shevchenko authored
%pa takes into consideration the special types such as resource_size_t. Use this specifier %instead of explicit casting. Link: http://lkml.kernel.org/r/20191209165413.56263-1-andriy.shevchenko@linux.intel.comSigned-off-by:
Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by:
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Gustavo A. R. Silva authored
In case memory resources for _ptr2_ were allocated, release them before return. Notice that in case _ptr1_ happens to be NULL, krealloc() behaves exactly like kmalloc(). Addresses-Coverity-ID: 1490594 ("Resource leak") Link: http://lkml.kernel.org/r/20200123160115.GA4202@embeddedor Fixes: 3f15801c ("lib: add kasan test module") Signed-off-by:Gustavo A. R. Silva <gustavo@embeddedor.com> Reviewed-by:
Dmitry Vyukov <dvyukov@google.com> Cc: <stable@vger.kernel.org> Signed-off-by:
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Junyong Sun authored
Print the call_site ip of kmem_alloc_node using '%pS' to improve the readability of raw slab trace points. Link: http://lkml.kernel.org/r/1577949568-4518-1-git-send-email-sunjunyong@xiaomi.comSigned-off-by:
Junyong Sun <sunjunyong@xiaomi.com> Acked-by:
Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Cc: Changbin Du <changbin.du@intel.com> Cc: Tim Murray <timmurray@google.com> Signed-off-by:
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Li Xinhai authored
When check_pte, pfn of normal, hugetlbfs and THP page need be compared. The current implementation apply comparison as - normal 4K page: page_pfn <= pfn < page_pfn + 1 - hugetlbfs page: page_pfn <= pfn < page_pfn + HPAGE_PMD_NR - THP page: page_pfn <= pfn < page_pfn + HPAGE_PMD_NR in pfn_in_hpage. For hugetlbfs page, it should be page_pfn == pfn Now, change pfn_in_hpage to pfn_is_match to highlight that comparison is not only for THP and explicitly compare for these cases. No impact upon current behavior, just make the code clear. I think it is important to make the code clear - comparing hugetlbfs page in range page_pfn <= pfn < page_pfn + HPAGE_PMD_NR is confusing. Link: http://lkml.kernel.org/r/1578737885-8890-1-git-send-email-lixinhai.lxh@gmail.comSigned-off-by:
Li Xinhai <lixinhai.lxh@gmail.com> Acked-by:
Mike Kravetz <mike.kravetz@oracle.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by:
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Kaitao Cheng authored
Compound pages handling in mem_cgroup_migrate is more convoluted than necessary. The state is duplicated in compound variable and the same could be achieved by PageTransHuge check which is trivial and hpage_nr_pages is already PageTransHuge aware. It is much simpler to just use hpage_nr_pages for nr_pages and replace the local variable by PageTransHuge check directly Link: http://lkml.kernel.org/r/20191210160450.3395-1-pilgrimtao@gmail.comSigned-off-by:
Kaitao Cheng <pilgrimtao@gmail.com> Acked-by:
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Vasily Averin authored
If seq_file .next fuction does not change position index, read after some lseek can generate unexpected output. In Aug 2018 NeilBrown noticed commit 1f4aace6 ("fs/seq_file.c: simplify seq_file iteration code and interface") "Some ->next functions do not increment *pos when they return NULL... Note that such ->next functions are buggy and should be fixed. A simple demonstration is dd if=/proc/swaps bs=1000 skip=1 Choose any block size larger than the size of /proc/swaps. This will always show the whole last line of /proc/swaps" Described problem is still actual. If you make lseek into middle of last output line following read will output end of last line and whole last line once again. $ dd if=/proc/swaps bs=1 # usual output Filename Type Size Used Priority /dev/dm-0 partition 4194812 97536 -2 104+0 records in 104+0 records out 104 bytes copied $ dd if=/proc/swaps bs=40 skip=1 # last line was generated twice dd: /proc/swaps: cannot skip to specified offset v/dm-0 partition 4194812 97536 -2 /dev/dm-0 partition 4194812 97536 -2 3+1 records in 3+1 records out 131 bytes copied https://bugzilla.kernel.org/show_bug.cgi?id=206283 Link: http://lkml.kernel.org/r/bd8cfd7b-ac95-9b91-f9e7-e8438bd5047d@virtuozzo.comSigned-off-by:
Vasily Averin <vvs@virtuozzo.com> Reviewed-by:
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John Hubbard authored
In order to provide a clearer, more symmetric API for pinning and unpinning DMA pages. This way, pin_user_pages*() calls match up with unpin_user_pages*() calls, and the API is a lot closer to being self-explanatory. Link: http://lkml.kernel.org/r/20200107224558.2362728-23-jhubbard@nvidia.comSigned-off-by:
John Hubbard <jhubbard@nvidia.com> Reviewed-by:
Jan Kara <jack@suse.cz> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Björn Töpel <bjorn.topel@intel.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Leon Romanovsky <leonro@mellanox.com> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by:
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John Hubbard authored
Fix the gup benchmark flags to use the symbolic FOLL_WRITE, instead of a hard-coded "1" value. Also, clean up the filtering of gup flags a little, by just doing it once before issuing any of the get_user_pages*() calls. This makes it harder to overlook, instead of having little "gup_flags & 1" phrases in the function calls. Link: http://lkml.kernel.org/r/20200107224558.2362728-22-jhubbard@nvidia.comSigned-off-by:
Ira Weiny <ira.weiny@intel.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Björn Töpel <bjorn.topel@intel.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl> Cc: Jan Kara <jack@suse.cz> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Leon Romanovsky <leonro@mellanox.com> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by:
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John Hubbard authored
1. Convert from get_user_pages() to pin_user_pages(). 2. As required by pin_user_pages(), release these pages via put_user_page(). Link: http://lkml.kernel.org/r/20200107224558.2362728-21-jhubbard@nvidia.comSigned-off-by:
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John Hubbard authored
1. Change vfio from get_user_pages_remote(), to pin_user_pages_remote(). 2. Because all FOLL_PIN-acquired pages must be released via put_user_page(), also convert the put_page() call over to put_user_pages_dirty_lock(). Note that this effectively changes the code's behavior in vfio_iommu_type1.c: put_pfn(): it now ultimately calls set_page_dirty_lock(), instead of set_page_dirty(). This is probably more accurate. As Christoph Hellwig put it, "set_page_dirty() is only safe if we are dealing with a file backed page where we have reference on the inode it hangs off." [1] [1] https://lore.kernel.org/r/20190723153640.GB720@lst.de Link: http://lkml.kernel.org/r/20200107224558.2362728-20-jhubbard@nvidia.comSigned-off-by:
Alex Williamson <alex.williamson@redhat.com> Acked-by:
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John Hubbard authored
1. Change v4l2 from get_user_pages() to pin_user_pages(). 2. Because all FOLL_PIN-acquired pages must be released via put_user_page(), also convert the put_page() call over to put_user_pages_dirty_lock(). Link: http://lkml.kernel.org/r/20200107224558.2362728-19-jhubbard@nvidia.comSigned-off-by:
Hans Verkuil <hverkuil-cisco@xs4all.nl> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Björn Töpel <bjorn.topel@intel.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jan Kara <jack@suse.cz> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Leon Romanovsky <leonro@mellanox.com> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by:
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John Hubbard authored
Convert net/xdp to use the new pin_longterm_pages() call, which sets FOLL_PIN. Setting FOLL_PIN is now required for code that requires tracking of pinned pages. In partial anticipation of this work, the net/xdp code was already calling put_user_page() instead of put_page(). Therefore, in order to convert from the get_user_pages()/put_page() model, to the pin_user_pages()/put_user_page() model, the only change required here is to change get_user_pages() to pin_user_pages(). Link: http://lkml.kernel.org/r/20200107224558.2362728-18-jhubbard@nvidia.comSigned-off-by:
Björn Töpel <bjorn.topel@intel.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Jan Kara <jack@suse.cz> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Leon Romanovsky <leonro@mellanox.com> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by:
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John Hubbard authored
Convert fs/io_uring to use the new pin_user_pages() call, which sets FOLL_PIN. Setting FOLL_PIN is now required for code that requires tracking of pinned pages, and therefore for any code that calls put_user_page(). In partial anticipation of this work, the io_uring code was already calling put_user_page() instead of put_page(). Therefore, in order to convert from the get_user_pages()/put_page() model, to the pin_user_pages()/put_user_page() model, the only change required here is to change get_user_pages() to pin_user_pages(). Link: http://lkml.kernel.org/r/20200107224558.2362728-17-jhubbard@nvidia.comSigned-off-by:
Jens Axboe <axboe@kernel.dk> Reviewed-by:
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John Hubbard authored
Convert drm/via to use the new pin_user_pages_fast() call, which sets FOLL_PIN. Setting FOLL_PIN is now required for code that requires tracking of pinned pages, and therefore for any code that calls put_user_page(). In partial anticipation of this work, the drm/via driver was already calling put_user_page() instead of put_page(). Therefore, in order to convert from the get_user_pages()/put_page() model, to the pin_user_pages()/put_user_page() model, the only change required is to change get_user_pages() to pin_user_pages(). Link: http://lkml.kernel.org/r/20200107224558.2362728-16-jhubbard@nvidia.comSigned-off-by:
Daniel Vetter <daniel.vetter@ffwll.ch> Reviewed-by:
Jérôme Glisse <jglisse@redhat.com> Reviewed-by:
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John Hubbard authored
Convert process_vm_access to use the new pin_user_pages_remote() call, which sets FOLL_PIN. Setting FOLL_PIN is now required for code that requires tracking of pinned pages. Also, release the pages via put_user_page*(). Also, rename "pages" to "pinned_pages", as this makes for easier reading of process_vm_rw_single_vec(). Link: http://lkml.kernel.org/r/20200107224558.2362728-15-jhubbard@nvidia.comSigned-off-by:
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John Hubbard authored
Convert infiniband to use the new pin_user_pages*() calls. Also, revert earlier changes to Infiniband ODP that had it using put_user_page(). ODP is "Case 3" in Documentation/core-api/pin_user_pages.rst, which is to say, normal get_user_pages() and put_page() is the API to use there. The new pin_user_pages*() calls replace corresponding get_user_pages*() calls, and set the FOLL_PIN flag. The FOLL_PIN flag requires that the caller must return the pages via put_user_page*() calls, but infiniband was already doing that as part of an earlier commit. Link: http://lkml.kernel.org/r/20200107224558.2362728-14-jhubbard@nvidia.comSigned-off-by:
Jason Gunthorpe <jgg@mellanox.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Björn Töpel <bjorn.topel@intel.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Jan Kara <jack@suse.cz> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Leon Romanovsky <leonro@mellanox.com> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by:
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John Hubbard authored
1. Call the new global pin_user_pages_fast(), from pin_goldfish_pages(). 2. As required by pin_user_pages(), release these pages via put_user_page(). In this case, do so via put_user_pages_dirty_lock(). That has the side effect of calling set_page_dirty_lock(), instead of set_page_dirty(). This is probably more accurate. As Christoph Hellwig put it, "set_page_dirty() is only safe if we are dealing with a file backed page where we have reference on the inode it hangs off." [1] Another side effect is that the release code is simplified because the page[] loop is now in gup.c instead of here, so just delete the local release_user_pages() entirely, and call put_user_pages_dirty_lock() directly, instead. [1] https://lore.kernel.org/r/20190723153640.GB720@lst.de Link: http://lkml.kernel.org/r/20200107224558.2362728-13-jhubbard@nvidia.comSigned-off-by:
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John Hubbard authored
Introduce pin_user_pages*() variations of get_user_pages*() calls, and also pin_longterm_pages*() variations. For now, these are placeholder calls, until the various call sites are converted to use the correct get_user_pages*() or pin_user_pages*() API. These variants will eventually all set FOLL_PIN, which is also introduced, and thoroughly documented. pin_user_pages() pin_user_pages_remote() pin_user_pages_fast() All pages that are pinned via the above calls, must be unpinned via put_user_page(). The underlying rules are: * FOLL_PIN is a gup-internal flag, so the call sites should not directly set it. That behavior is enforced with assertions. * Call sites that want to indicate that they are going to do DirectIO ("DIO") or something with similar characteristics, should call a get_user_pages()-like wrapper call that sets FOLL_PIN. These wrappers will: * Start with "pin_user_pages" instead of "get_user_pages". That makes it easy to find and audit the call sites. * Set FOLL_PIN * For pages that are received via FOLL_PIN, those pages must be returned via put_user_page(). Thanks to Jan Kara and Vlastimil Babka for explaining the 4 cases in this documentation. (I've reworded it and expanded upon it.) Link: http://lkml.kernel.org/r/20200107224558.2362728-12-jhubbard@nvidia.comSigned-off-by: -
John Hubbard authored
After DMA is complete, and the device and CPU caches are synchronized, it's still required to mark the CPU pages as dirty, if the data was coming from the device. However, this driver was just issuing a bare put_page() call, without any set_page_dirty*() call. Fix the problem, by calling set_page_dirty_lock() if the CPU pages were potentially receiving data from the device. Link: http://lkml.kernel.org/r/20200107224558.2362728-11-jhubbard@nvidia.comSigned-off-by:
Christoph Hellwig <hch@lst.de> Acked-by:
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John Hubbard authored
And get rid of the mmap_sem calls, as part of that. Note that get_user_pages_fast() will, if necessary, fall back to __gup_longterm_unlocked(), which takes the mmap_sem as needed. Link: http://lkml.kernel.org/r/20200107224558.2362728-10-jhubbard@nvidia.comSigned-off-by:
Leon Romanovsky <leonro@mellanox.com> Reviewed-by:
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John Hubbard authored
Commit 817be129 ("mm: validate get_user_pages_fast flags") allowed only FOLL_WRITE and FOLL_LONGTERM to be passed to get_user_pages_fast(). This, combined with the fact that get_user_pages_fast() falls back to "slow gup", which *does* accept FOLL_FORCE, leads to an odd situation: if you need FOLL_FORCE, you cannot call get_user_pages_fast(). There does not appear to be any reason for filtering out FOLL_FORCE. There is nothing in the _fast() implementation that requires that we avoid writing to the pages. So it appears to have been an oversight. Fix by allowing FOLL_FORCE to be set for get_user_pages_fast(). Link: http://lkml.kernel.org/r/20200107224558.2362728-9-jhubbard@nvidia.com Fixes: 817be129 ("mm: validate get_user_pages_fast flags") Signed-off-by:
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John Hubbard authored
Update VFIO to take advantage of the recently loosened restriction on FOLL_LONGTERM with get_user_pages_remote(). Also, now it is possible to fix a bug: the VFIO caller is logically a FOLL_LONGTERM user, but it wasn't setting FOLL_LONGTERM. Also, remove an unnessary pair of calls that were releasing and reacquiring the mmap_sem. There is no need to avoid holding mmap_sem just in order to call page_to_pfn(). Also, now that the the DAX check ("if a VMA is DAX, don't allow long term pinning") is in the internals of get_user_pages_remote() and __gup_longterm_locked(), there's no need for it at the VFIO call site. So remove it. Link: http://lkml.kernel.org/r/20200107224558.2362728-8-jhubbard@nvidia.comSigned-off-by:Jason Gunthorpe <jgg@ziepe.ca> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Björn Töpel <bjorn.topel@intel.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl> Cc: Jan Kara <jack@suse.cz> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Leon Romanovsky <leonro@mellanox.com> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by:
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John Hubbard authored
As it says in the updated comment in gup.c: current FOLL_LONGTERM behavior is incompatible with FAULT_FLAG_ALLOW_RETRY because of the FS DAX check requirement on vmas. However, the corresponding restriction in get_user_pages_remote() was slightly stricter than is actually required: it forbade all FOLL_LONGTERM callers, but we can actually allow FOLL_LONGTERM callers that do not set the "locked" arg. Update the code and comments to loosen the restriction, allowing FOLL_LONGTERM in some cases. Also, copy the DAX check ("if a VMA is DAX, don't allow long term pinning") from the VFIO call site, all the way into the internals of get_user_pages_remote() and __gup_longterm_locked(). That is: get_user_pages_remote() calls __gup_longterm_locked(), which in turn calls check_dax_vmas(). This check will then be removed from the VFIO call site in a subsequent patch. Thanks to Jason Gunthorpe for pointing out a clean way to fix this, and to Dan Williams for helping clarify the DAX refactoring. Link: http://lkml.kernel.org/r/20200107224558.2362728-7-jhubbard@nvidia.comSigned-off-by: -
John Hubbard authored
Avoid naming conflicts: rename local static function from "pin_user_pages()" to "goldfish_pin_pages()". An upcoming patch will introduce a global pin_user_pages() function. Link: http://lkml.kernel.org/r/20200107224558.2362728-6-jhubbard@nvidia.comSigned-off-by:
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John Hubbard authored
An upcoming patch changes and complicates the refcounting and especially the "put page" aspects of it. In order to keep everything clean, refactor the devmap page release routines: * Rename put_devmap_managed_page() to page_is_devmap_managed(), and limit the functionality to "read only": return a bool, with no side effects. * Add a new routine, put_devmap_managed_page(), to handle decrementing the refcount for ZONE_DEVICE pages. * Change callers (just release_pages() and put_page()) to check page_is_devmap_managed() before calling the new put_devmap_managed_page() routine. This is a performance point: put_page() is a hot path, so we need to avoid non- inline function calls where possible. * Rename __put_devmap_managed_page() to free_devmap_managed_page(), and limit the functionality to unconditionally freeing a devmap page. This is originally based on a separate patch by Ira Weiny, which applied to an early version of the put_user_page() experiments. Since then, Jérôme Glisse suggested the refactoring described above. Link: http://lkml.kernel.org/r/20200107224558.2362728-5-jhubbard@nvidia.comSigned-off-by:
Dan Williams <dan.j.williams@intel.com> Reviewed-by:
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Dan Williams authored
After the removal of the device-public infrastructure there are only 2 ->page_free() call backs in the kernel. One of those is a device-private callback in the nouveau driver, the other is a generic wakeup needed in the DAX case. In the hopes that all ->page_free() callbacks can be migrated to common core kernel functionality, move the device-private specific actions in __put_devmap_managed_page() under the is_device_private_page() conditional, including the ->page_free() callback. For the other page types just open-code the generic wakeup. Yes, the wakeup is only needed in the MEMORY_DEVICE_FSDAX case, but it does no harm in the MEMORY_DEVICE_DEVDAX and MEMORY_DEVICE_PCI_P2PDMA case. Link: http://lkml.kernel.org/r/20200107224558.2362728-4-jhubbard@nvidia.comSigned-off-by:
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John Hubbard authored
An upcoming patch uses try_get_compound_head() more widely, so move it to the top of gup.c. Also fix a tiny spelling error and a checkpatch.pl warning. Link: http://lkml.kernel.org/r/20200107224558.2362728-3-jhubbard@nvidia.comSigned-off-by:
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John Hubbard authored
Patch series "mm/gup: prereqs to track dma-pinned pages: FOLL_PIN", v12. Overview: This is a prerequisite to solving the problem of proper interactions between file-backed pages, and [R]DMA activities, as discussed in [1], [2], [3], and in a remarkable number of email threads since about 2017. :) A new internal gup flag, FOLL_PIN is introduced, and thoroughly documented in the last patch's Documentation/vm/pin_user_pages.rst. I believe that this will provide a good starting point for doing the layout lease work that Ira Weiny has been working on. That's because these new wrapper functions provide a clean, constrained, systematically named set of functionality that, again, is required in order to even know if a page is "dma-pinned". In contrast to earlier approaches, the page tracking can be incrementally applied to the kernel call sites that, until now, have been simply calling get_user_pages() ("gup"). In other words, opt-in by changing from this: get_user_pages() (sets FOLL_GET) put_page() to this: pin_user_pages() (sets FOLL_PIN) unpin_user_page() Testing: * I've done some overall kernel testing (LTP, and a few other goodies), and some directed testing to exercise some of the changes. And as you can see, gup_benchmark is enhanced to exercise this. Basically, I've been able to runtime test the core get_user_pages() and pin_user_pages() and related routines, but not so much on several of the call sites--but those are generally just a couple of lines changed, each. Not much of the kernel is actually using this, which on one hand reduces risk quite a lot. But on the other hand, testing coverage is low. So I'd love it if, in particular, the Infiniband and PowerPC folks could do a smoke test of this series for me. Runtime testing for the call sites so far is pretty light: * io_uring: Some directed tests from liburing exercise this, and they pass. * process_vm_access.c: A small directed test passes. * gup_benchmark: the enhanced version hits the new gup.c code, and passes. * infiniband: Ran rdma-core tests: rdma-core/build/bin/run_tests.py * VFIO: compiles (I'm vowing to set up a run time test soon, but it's not ready just yet) * powerpc: it compiles... * drm/via: compiles... * goldfish: compiles... * net/xdp: compiles... * media/v4l2: compiles... [1] Some slow progress on get_user_pages() (Apr 2, 2019): https://lwn.net/Articles/784574/ [2] DMA and get_user_pages() (LPC: Dec 12, 2018): https://lwn.net/Articles/774411/ [3] The trouble with get_user_pages() (Apr 30, 2018): https://lwn.net/Articles/753027/ This patch (of 22): There are four locations in gup.c that have a fair amount of code duplication. This means that changing one requires making the same changes in four places, not to mention reading the same code four times, and wondering if there are subtle differences. Factor out the common code into static functions, thus reducing the overall line count and the code's complexity. Also, take the opportunity to slightly improve the efficiency of the error cases, by doing a mass subtraction of the refcount, surrounded by get_page()/put_page(). Also, further simplify (slightly), by waiting until the the successful end of each routine, to increment *nr. Link: http://lkml.kernel.org/r/20200107224558.2362728-2-jhubbard@nvidia.comSigned-off-by: -
Wei Yang authored
No functional change, just leverage the helper function to improve readability as others. Link: http://lkml.kernel.org/r/20200113070322.26627-1-richardw.yang@linux.intel.comSigned-off-by:
Wei Yang <richardw.yang@linux.intel.com> Acked-by:
Vlastimil Babka <vbabka@suse.cz> Acked-by:
Ralph Campbell <rcampbell@nvidia.com> Signed-off-by:
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Qiujun Huang authored
sorry for not processing for a long time. I met it again. patch v1 https://lkml.org/lkml/2019/9/20/656 do_machine_check() do_memory_failure() memory_failure() hw_poison_user_mappings() try_to_unmap() pteval = swp_entry_to_pte(make_hwpoison_entry(subpage)); ...and now we have a swap entry that indicates that the page entry refers to a bad (and poisoned) page of memory, but gup_fast() at this level of the page table was ignoring swap entries, and incorrectly assuming that "!pxd_none() == valid and present". And this was not just a poisoned page problem, but a generaly swap entry problem. So, any swap entry type (device memory migration, numa migration, or just regular swapping) could lead to the same problem. Fix this by checking for pxd_present(), instead of pxd_none(). Link: http://lkml.kernel.org/r/1578479084-15508-1-git-send-email-hqjagain@gmail.comSigned-off-by:
Qiujun Huang <hqjagain@gmail.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by:
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