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2017-02-23mm: drop unused argument of zap_page_range()Kirill A. Shutemov1-3/+2
There's no users of zap_page_range() who wants non-NULL 'details'. Let's drop it. Link: http://lkml.kernel.org/r/20170118122429.43661-3-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-23mm: drop zap_details::check_swap_entriesKirill A. Shutemov1-2/+2
detail == NULL would give the same functionality as .check_swap_entries==true. Link: http://lkml.kernel.org/r/20170118122429.43661-2-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-23mm: drop zap_details::ignore_dirtyKirill A. Shutemov1-6/+0
The only user of ignore_dirty is oom-reaper. But it doesn't really use it. ignore_dirty only has effect on file pages mapped with dirty pte. But oom-repear skips shared VMAs, so there's no way we can dirty file pte in them. Link: http://lkml.kernel.org/r/20170118122429.43661-1-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-23userfaultfd: hugetlbfs: fix __mcopy_atomic_hugetlb retry/error processingMike Kravetz1-3/+10
The new routine copy_huge_page_from_user() uses kmap_atomic() to map PAGE_SIZE pages. However, this prevents page faults in the subsequent call to copy_from_user(). This is OK in the case where the routine is copied with mmap_sema held. However, in another case we want to allow page faults. So, add a new argument allow_pagefault to indicate if the routine should allow page faults. [dan.carpenter@oracle.com: unmap the correct pointer] Link: http://lkml.kernel.org/r/20170113082608.GA3548@mwanda [akpm@linux-foundation.org: kunmap() takes a page*, per Hugh] Link: http://lkml.kernel.org/r/20161216144821.5183-20-aarcange@redhat.com Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Cc: Michael Rapoport <RAPOPORT@il.ibm.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Hugh Dickins <hughd@google.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-23userfaultfd: hugetlbfs: add copy_huge_page_from_user for hugetlb userfaultfd ↵Mike Kravetz1-0/+25
support userfaultfd UFFDIO_COPY allows user level code to copy data to a page at fault time. The data is copied from user space to a newly allocated huge page. The new routine copy_huge_page_from_user performs this copy. Link: http://lkml.kernel.org/r/20161216144821.5183-17-aarcange@redhat.com Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Cc: Michael Rapoport <RAPOPORT@il.ibm.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-23mm, dax: change pmd_fault() to take only vmf parameterDave Jiang1-5/+4
pmd_fault() and related functions really only need the vmf parameter since the additional parameters are all included in the vmf struct. Remove the additional parameter and simplify pmd_fault() and friends. Link: http://lkml.kernel.org/r/1484085142-2297-8-git-send-email-ross.zwisler@linux.intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Matthew Wilcox <mawilcox@microsoft.com> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-23mm, dax: make pmd_fault() and friends be the same as fault()Dave Jiang1-4/+2
Instead of passing in multiple parameters in the pmd_fault() handler, a vmf can be passed in just like a fault() handler. This will simplify code and remove the need for the actual pmd fault handlers to allocate a vmf. Related functions are also modified to do the same. [dave.jiang@intel.com: fix issue with xfs_tests stall when DAX option is off] Link: http://lkml.kernel.org/r/148469861071.195597.3619476895250028518.stgit@djiang5-desk3.ch.intel.com Link: http://lkml.kernel.org/r/1484085142-2297-7-git-send-email-ross.zwisler@linux.intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Dave Chinner <david@fromorbit.com> Cc: Matthew Wilcox <mawilcox@microsoft.com> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-01-11dax: wrprotect pmd_t in dax_mapping_entry_mkcleanRoss Zwisler1-2/+2
Currently dax_mapping_entry_mkclean() fails to clean and write protect the pmd_t of a DAX PMD entry during an *sync operation. This can result in data loss in the following sequence: 1) mmap write to DAX PMD, dirtying PMD radix tree entry and making the pmd_t dirty and writeable 2) fsync, flushing out PMD data and cleaning the radix tree entry. We currently fail to mark the pmd_t as clean and write protected. 3) more mmap writes to the PMD. These don't cause any page faults since the pmd_t is dirty and writeable. The radix tree entry remains clean. 4) fsync, which fails to flush the dirty PMD data because the radix tree entry was clean. 5) crash - dirty data that should have been fsync'd as part of 4) could still have been in the processor cache, and is lost. Fix this by marking the pmd_t clean and write protected in dax_mapping_entry_mkclean(), which is called as part of the fsync operation 2). This will cause the writes in step 3) above to generate page faults where we'll re-dirty the PMD radix tree entry, resulting in flushes in the fsync that happens in step 4). Fixes: 4b4bb46d00b3 ("dax: clear dirty entry tags on cache flush") Link: http://lkml.kernel.org/r/1482272586-21177-3-git-send-email-ross.zwisler@linux.intel.com Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Jan Kara <jack@suse.cz> Cc: Matthew Wilcox <mawilcox@microsoft.com> Cc: Dave Hansen <dave.hansen@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-01-11mm: add follow_pte_pmd()Ross Zwisler1-7/+30
Patch series "Write protect DAX PMDs in *sync path". Currently dax_mapping_entry_mkclean() fails to clean and write protect the pmd_t of a DAX PMD entry during an *sync operation. This can result in data loss, as detailed in patch 2. This series is based on Dan's "libnvdimm-pending" branch, which is the current home for Jan's "dax: Page invalidation fixes" series. You can find a working tree here: https://git.kernel.org/cgit/linux/kernel/git/zwisler/linux.git/log/?h=dax_pmd_clean This patch (of 2): Similar to follow_pte(), follow_pte_pmd() allows either a PTE leaf or a huge page PMD leaf to be found and returned. Link: http://lkml.kernel.org/r/1482272586-21177-2-git-send-email-ross.zwisler@linux.intel.com Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> Suggested-by: Dave Hansen <dave.hansen@intel.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Jan Kara <jack@suse.cz> Cc: Matthew Wilcox <mawilcox@microsoft.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-01-08mm: stop leaking PageTablesHugh Dickins1-27/+20
4.10-rc loadtest (even on x86, and even without THPCache) fails with "fork: Cannot allocate memory" or some such; and /proc/meminfo shows PageTables growing. Commit 953c66c2b22a ("mm: THP page cache support for ppc64") that got merged in rc1 removed the freeing of an unused preallocated pagetable after do_fault_around() has called map_pages(). This is usually a good optimization, so that the followup doesn't have to reallocate one; but it's not sufficient to shift the freeing into alloc_set_pte(), since there are failure cases (most commonly VM_FAULT_RETRY) which never reach finish_fault(). Check and free it at the outer level in do_fault(), then we don't need to worry in alloc_set_pte(), and can restore that to how it was (I cannot find any reason to pte_free() under lock as it was doing). And fix a separate pagetable leak, or crash, introduced by the same change, that could only show up on some ppc64: why does do_set_pmd()'s failure case attempt to withdraw a pagetable when it never deposited one, at the same time overwriting (so leaking) the vmf->prealloc_pte? Residue of an earlier implementation, perhaps? Delete it. Fixes: 953c66c2b22a ("mm: THP page cache support for ppc64") Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Michael Neuling <mikey@neuling.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24Replace <asm/uaccess.h> with <linux/uaccess.h> globallyLinus Torvalds1-1/+1
This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>' sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-15Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-425/+434
Merge more updates from Andrew Morton: - a few misc things - kexec updates - DMA-mapping updates to better support networking DMA operations - IPC updates - various MM changes to improve DAX fault handling - lots of radix-tree changes, mainly to the test suite. All leading up to reimplementing the IDA/IDR code to be a wrapper layer over the radix-tree. However the final trigger-pulling patch is held off for 4.11. * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (114 commits) radix tree test suite: delete unused rcupdate.c radix tree test suite: add new tag check radix-tree: ensure counts are initialised radix tree test suite: cache recently freed objects radix tree test suite: add some more functionality idr: reduce the number of bits per level from 8 to 6 rxrpc: abstract away knowledge of IDR internals tpm: use idr_find(), not idr_find_slowpath() idr: add ida_is_empty radix tree test suite: check multiorder iteration radix-tree: fix replacement for multiorder entries radix-tree: add radix_tree_split_preload() radix-tree: add radix_tree_split radix-tree: add radix_tree_join radix-tree: delete radix_tree_range_tag_if_tagged() radix-tree: delete radix_tree_locate_item() radix-tree: improve multiorder iterators btrfs: fix race in btrfs_free_dummy_fs_info() radix-tree: improve dump output radix-tree: make radix_tree_find_next_bit more useful ...
2016-12-15dax: protect PTE modification on WP fault by radix tree entry lockJan Kara1-1/+1
Currently PTE gets updated in wp_pfn_shared() after dax_pfn_mkwrite() has released corresponding radix tree entry lock. When we want to writeprotect PTE on cache flush, we need PTE modification to happen under radix tree entry lock to ensure consistent updates of PTE and radix tree (standard faults use page lock to ensure this consistency). So move update of PTE bit into dax_pfn_mkwrite(). Link: http://lkml.kernel.org/r/1479460644-25076-20-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-15mm: export follow_pte()Jan Kara1-2/+2
DAX will need to implement its own version of page_check_address(). To avoid duplicating page table walking code, export follow_pte() which does what we need. Link: http://lkml.kernel.org/r/1479460644-25076-18-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-15mm: change return values of finish_mkwrite_fault()Jan Kara1-4/+3
Currently finish_mkwrite_fault() returns 0 when PTE got changed before we acquired PTE lock and VM_FAULT_WRITE when we succeeded in modifying the PTE. This is somewhat confusing since 0 generally means success, it is also inconsistent with finish_fault() which returns 0 on success. Change finish_mkwrite_fault() to return 0 on success and VM_FAULT_NOPAGE when PTE changed. Practically, there should be no behavioral difference since we bail out from the fault the same way regardless whether we return 0, VM_FAULT_NOPAGE, or VM_FAULT_WRITE. Also note that VM_FAULT_WRITE has no effect for shared mappings since the only two places that check it - KSM and GUP - care about private mappings only. Generally the meaning of VM_FAULT_WRITE for shared mappings is not well defined and we should probably clean that up. Link: http://lkml.kernel.org/r/1479460644-25076-17-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-15mm: provide helper for finishing mkwrite faultsJan Kara1-27/+40
Provide a helper function for finishing write faults due to PTE being read-only. The helper will be used by DAX to avoid the need of complicating generic MM code with DAX locking specifics. Link: http://lkml.kernel.org/r/1479460644-25076-16-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-15mm: move part of wp_page_reuse() into the single call siteJan Kara1-15/+12
wp_page_reuse() handles write shared faults which is needed only in wp_page_shared(). Move the handling only into that location to make wp_page_reuse() simpler and avoid a strange situation when we sometimes pass in locked page, sometimes unlocked etc. Link: http://lkml.kernel.org/r/1479460644-25076-15-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-15mm: use vmf->page during WP faultsJan Kara1-29/+29
So far we set vmf->page during WP faults only when we needed to pass it to the ->page_mkwrite handler. Set it in all the cases now and use that instead of passing page pointer explicitly around. Link: http://lkml.kernel.org/r/1479460644-25076-14-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-15mm: pass vm_fault structure into do_page_mkwrite()Jan Kara1-12/+10
We will need more information in the ->page_mkwrite() helper for DAX to be able to fully finish faults there. Pass vm_fault structure to do_page_mkwrite() and use it there so that information propagates properly from upper layers. Link: http://lkml.kernel.org/r/1479460644-25076-13-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-15mm: factor out common parts of write fault handlingJan Kara1-41/+37
Currently we duplicate handling of shared write faults in wp_page_reuse() and do_shared_fault(). Factor them out into a common function. Link: http://lkml.kernel.org/r/1479460644-25076-12-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-15mm: move handling of COW faults into DAX codeJan Kara1-9/+4
Move final handling of COW faults from generic code into DAX fault handler. That way generic code doesn't have to be aware of peculiarities of DAX locking so remove that knowledge and make locking functions private to fs/dax.c. Link: http://lkml.kernel.org/r/1479460644-25076-11-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-15mm: factor out functionality to finish page faultsJan Kara1-9/+35
Introduce finish_fault() as a helper function for finishing page faults. It is rather thin wrapper around alloc_set_pte() but since we'd want to call this from DAX code or filesystems, it is still useful to avoid some boilerplate code. Link: http://lkml.kernel.org/r/1479460644-25076-10-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-15mm: allow full handling of COW faults in ->fault handlersJan Kara1-7/+7
Patch series "dax: Clear dirty bits after flushing caches", v5. Patchset to clear dirty bits from radix tree of DAX inodes when caches for corresponding pfns have been flushed. In principle, these patches enable handlers to easily update PTEs and do other work necessary to finish the fault without duplicating the functionality present in the generic code. I'd like to thank Kirill and Ross for reviews of the series! This patch (of 20): To allow full handling of COW faults add memcg field to struct vm_fault and a return value of ->fault() handler meaning that COW fault is fully handled and memcg charge must not be canceled. This will allow us to remove knowledge about special DAX locking from the generic fault code. Link: http://lkml.kernel.org/r/1479460644-25076-9-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-15mm: add orig_pte field into vm_faultJan Kara1-41/+41
Add orig_pte field to vm_fault structure to allow ->page_mkwrite handlers to fully handle the fault. This also allows us to save some passing of extra arguments around. Link: http://lkml.kernel.org/r/1479460644-25076-8-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-15mm: use passed vm_fault structure for in wp_pfn_shared()Jan Kara1-7/+2
Instead of creating another vm_fault structure, use the one passed to wp_pfn_shared() for passing arguments into pfn_mkwrite handler. Link: http://lkml.kernel.org/r/1479460644-25076-7-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-15mm: trim __do_fault() argumentsJan Kara1-38/+29
Use vm_fault structure to pass cow_page, page, and entry in and out of the function. That reduces number of __do_fault() arguments from 4 to 1. Link: http://lkml.kernel.org/r/1479460644-25076-6-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-15mm: use passed vm_fault structure in __do_fault()Jan Kara1-15/+10
Instead of creating another vm_fault structure, use the one passed to __do_fault() for passing arguments into fault handler. Link: http://lkml.kernel.org/r/1479460644-25076-5-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-15mm: use pgoff in struct vm_fault instead of passing it separatelyJan Kara1-17/+18
struct vm_fault has already pgoff entry. Use it instead of passing pgoff as a separate argument and then assigning it later. Link: http://lkml.kernel.org/r/1479460644-25076-4-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-15mm: use vmf->address instead of of vmf->virtual_addressJan Kara1-5/+4
Every single user of vmf->virtual_address typed that entry to unsigned long before doing anything with it so the type of virtual_address does not really provide us any additional safety. Just use masked vmf->address which already has the appropriate type. Link: http://lkml.kernel.org/r/1479460644-25076-3-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-15mm: join struct fault_env and vm_faultJan Kara1-282/+286
Currently we have two different structures for passing fault information around - struct vm_fault and struct fault_env. DAX will need more information in struct vm_fault to handle its faults so the content of that structure would become event closer to fault_env. Furthermore it would need to generate struct fault_env to be able to call some of the generic functions. So at this point I don't think there's much use in keeping these two structures separate. Just embed into struct vm_fault all that is needed to use it for both purposes. Link: http://lkml.kernel.org/r/1479460644-25076-2-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-15mm: add locked parameter to get_user_pages_remote()Lorenzo Stoakes1-1/+1
Patch series "mm: unexport __get_user_pages_unlocked()". This patch series continues the cleanup of get_user_pages*() functions taking advantage of the fact we can now pass gup_flags as we please. It firstly adds an additional 'locked' parameter to get_user_pages_remote() to allow for its callers to utilise VM_FAULT_RETRY functionality. This is necessary as the invocation of __get_user_pages_unlocked() in process_vm_rw_single_vec() makes use of this and no other existing higher level function would allow it to do so. Secondly existing callers of __get_user_pages_unlocked() are replaced with the appropriate higher-level replacement - get_user_pages_unlocked() if the current task and memory descriptor are referenced, or get_user_pages_remote() if other task/memory descriptors are referenced (having acquiring mmap_sem.) This patch (of 2): Add a int *locked parameter to get_user_pages_remote() to allow VM_FAULT_RETRY faulting behaviour similar to get_user_pages_[un]locked(). Taking into account the previous adjustments to get_user_pages*() functions allowing for the passing of gup_flags, we are now in a position where __get_user_pages_unlocked() need only be exported for his ability to allow VM_FAULT_RETRY behaviour, this adjustment allows us to subsequently unexport __get_user_pages_unlocked() as well as allowing for future flexibility in the use of get_user_pages_remote(). [sfr@canb.auug.org.au: merge fix for get_user_pages_remote API change] Link: http://lkml.kernel.org/r/20161122210511.024ec341@canb.auug.org.au Link: http://lkml.kernel.org/r/20161027095141.2569-2-lstoakes@gmail.com Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Jan Kara <jack@suse.cz> Cc: Hugh Dickins <hughd@google.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Rik van Riel <riel@redhat.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krcmar <rkrcmar@redhat.com> Signed-off-by: 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>
2016-12-15Merge branch 'for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull namespace updates from Eric Biederman: "After a lot of discussion and work we have finally reachanged a basic understanding of what is necessary to make unprivileged mounts safe in the presence of EVM and IMA xattrs which the last commit in this series reflects. While technically it is a revert the comments it adds are important for people not getting confused in the future. Clearing up that confusion allows us to seriously work on unprivileged mounts of fuse in the next development cycle. The rest of the fixes in this set are in the intersection of user namespaces, ptrace, and exec. I started with the first fix which started a feedback cycle of finding additional issues during review and fixing them. Culiminating in a fix for a bug that has been present since at least Linux v1.0. Potentially these fixes were candidates for being merged during the rc cycle, and are certainly backport candidates but enough little things turned up during review and testing that I decided they should be handled as part of the normal development process just to be certain there were not any great surprises when it came time to backport some of these fixes" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: Revert "evm: Translate user/group ids relative to s_user_ns when computing HMAC" exec: Ensure mm->user_ns contains the execed files ptrace: Don't allow accessing an undumpable mm ptrace: Capture the ptracer's creds not PT_PTRACE_CAP mm: Add a user_ns owner to mm_struct and fix ptrace permission checks
2016-12-13Merge tag 'char-misc-4.10-rc1' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc driver updates from Greg KH: "Here's the big char/misc driver patches for 4.10-rc1. Lots of tiny changes over lots of "minor" driver subsystems, the largest being some new FPGA drivers. Other than that, a few other new drivers, but no new driver subsystems added for this kernel cycle, a nice change. All of these have been in linux-next with no reported issues" * tag 'char-misc-4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (107 commits) uio-hv-generic: store physical addresses instead of virtual Tools: hv: kvp: configurable external scripts path uio-hv-generic: new userspace i/o driver for VMBus vmbus: add support for dynamic device id's hv: change clockevents unbind tactics hv: acquire vmbus_connection.channel_mutex in vmbus_free_channels() hyperv: Fix spelling of HV_UNKOWN mei: bus: enable non-blocking RX mei: fix the back to back interrupt handling mei: synchronize irq before initiating a reset. VME: Remove shutdown entry from vme_driver auxdisplay: ht16k33: select framebuffer helper modules MAINTAINERS: add git url for fpga fpga: Clarify how write_init works streaming modes fpga zynq: Fix incorrect ISR state on bootup fpga zynq: Remove priv->dev fpga zynq: Add missing \n to messages fpga: Add COMPILE_TEST to all drivers uio: pruss: add clk_disable() char/pcmcia: add some error checking in scr24x_read() ...
2016-12-13mm: THP page cache support for ppc64Aneesh Kumar K.V1-10/+50
Add arch specific callback in the generic THP page cache code that will deposit and withdarw preallocated page table. Archs like ppc64 use this preallocated table to store the hash pte slot information. Testing: kernel build of the patch series on tmpfs mounted with option huge=always The related thp stat: thp_fault_alloc 72939 thp_fault_fallback 60547 thp_collapse_alloc 603 thp_collapse_alloc_failed 0 thp_file_alloc 253763 thp_file_mapped 4251 thp_split_page 51518 thp_split_page_failed 1 thp_deferred_split_page 73566 thp_split_pmd 665 thp_zero_page_alloc 3 thp_zero_page_alloc_failed 0 [akpm@linux-foundation.org: remove unneeded parentheses, per Kirill] Link: http://lkml.kernel.org/r/20161113150025.17942-2-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> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Michael Neuling <mikey@neuling.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-13mm: remove the page size change check in tlb_remove_pageAneesh Kumar K.V1-15/+6
Now that we check for page size change early in the loop, we can partially revert e9d55e157034a ("mm: change the interface for __tlb_remove_page"). This simplies the code much, by removing the need to track the last address with which we adjusted the range. We also go back to the older way of filling the mmu_gather array, ie, we add an entry and then check whether the gather batch is full. Link: http://lkml.kernel.org/r/20161026084839.27299-6-aneesh.kumar@linux.vnet.ibm.com Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-13mm: add tlb_remove_check_page_size_change to track page size changeAneesh Kumar K.V1-1/+6
With commit e77b0852b551 ("mm/mmu_gather: track page size with mmu gather and force flush if page size change") we added the ability to force a tlb flush when the page size change in a mmu_gather loop. We did that by checking for a page size change every time we added a page to mmu_gather for lazy flush/remove. We can improve that by moving the page size change check early and not doing it every time we add a page. This also helps us to do tlb flush when invalidating a range covering dax mapping. Wrt dax mapping we don't have a backing struct page and hence we don't call tlb_remove_page, which earlier forced the tlb flush on page size change. Moving the page size change check earlier means we will do the same even for dax mapping. We also avoid doing this check on architecture other than powerpc. In a later patch we will remove page size check from tlb_remove_page(). Link: http://lkml.kernel.org/r/20161026084839.27299-5-aneesh.kumar@linux.vnet.ibm.com Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-13mm, thp: avoid unlikely branches for split_huge_pmdDavid Rientjes1-2/+2
While doing MADV_DONTNEED on a large area of thp memory, I noticed we encountered many unlikely() branches in profiles for each backing hugepage. This is because zap_pmd_range() would call split_huge_pmd(), which rechecked the conditions that were already validated, but as part of an unlikely() branch. Avoid the unlikely() branch when in a context where pmd is known to be good for __split_huge_pmd() directly. Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1610181600300.84525@chino.kir.corp.google.com Signed-off-by: David Rientjes <rientjes@google.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-11-22ptrace: Don't allow accessing an undumpable mmEric W. Biederman1-1/+1
It is the reasonable expectation that if an executable file is not readable there will be no way for a user without special privileges to read the file. This is enforced in ptrace_attach but if ptrace is already attached before exec there is no enforcement for read-only executables. As the only way to read such an mm is through access_process_vm spin a variant called ptrace_access_vm that will fail if the target process is not being ptraced by the current process, or the current process did not have sufficient privileges when ptracing began to read the target processes mm. In the ptrace implementations replace access_process_vm by ptrace_access_vm. There remain several ptrace sites that still use access_process_vm as they are reading the target executables instructions (for kernel consumption) or register stacks. As such it does not appear necessary to add a permission check to those calls. This bug has always existed in Linux. Fixes: v1.0 Cc: stable@vger.kernel.org Reported-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2016-11-10lkdtm: Do not use flush_icache_range() on user addressesCatalin Marinas1-0/+1
The flush_icache_range() API is meant to be used on kernel addresses only as it may not have the infrastructure (exception entries) to handle user memory faults. The lkdtm execute_user_location() function tests the kernel execution of user space addresses by mmap'ing an anonymous page, copying some code together with cache maintenance and attempting to run it. However, the cache maintenance step may fail because of the incorrect API usage described above. The patch changes lkdtm to use access_process_vm() for copying the code into user space which would take care of the necessary cache maintenance. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> [kees: export access_process_vm() for module use] Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-09x86/pat, mm: Make track_pfn_insert() return voidBorislav Petkov1-4/+4
It only returns 0 so we can save us the testing of its retval everywhere. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: mcgrof@suse.com Cc: dri-devel@lists.freedesktop.org Cc: Andy Lutomirski <luto@kernel.org> Cc: Dave Airlie <airlied@redhat.com> Cc: dan.j.williams@intel.com Cc: torvalds@linux-foundation.org Link: http://lkml.kernel.org/r/20161026174839.rusfxkm3xt4ennhe@pd.tnic Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-10-19mm: replace access_process_vm() write parameter with gup_flagsLorenzo Stoakes1-6/+2
This removes the 'write' argument from access_process_vm() and replaces it with 'gup_flags' as use of this function previously silently implied FOLL_FORCE, whereas after this patch callers explicitly pass this flag. We make this explicit as use of FOLL_FORCE can result in surprising behaviour (and hence bugs) within the mm subsystem. Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-19mm: replace access_remote_vm() write parameter with gup_flagsLorenzo Stoakes1-8/+3
This removes the 'write' argument from access_remote_vm() and replaces it with 'gup_flags' as use of this function previously silently implied FOLL_FORCE, whereas after this patch callers explicitly pass this flag. We make this explicit as use of FOLL_FORCE can result in surprising behaviour (and hence bugs) within the mm subsystem. Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-19mm: replace __access_remote_vm() write parameter with gup_flagsLorenzo Stoakes1-8/+15
This removes the 'write' argument from __access_remote_vm() and replaces it with 'gup_flags' as use of this function previously silently implied FOLL_FORCE, whereas after this patch callers explicitly pass this flag. We make this explicit as use of FOLL_FORCE can result in surprising behaviour (and hence bugs) within the mm subsystem. Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-19mm: replace get_user_pages_remote() write/force parameters with gup_flagsLorenzo Stoakes1-1/+5
This removes the 'write' and 'force' from get_user_pages_remote() and replaces them with 'gup_flags' to make the use of FOLL_FORCE explicit in callers as use of this flag can result in surprising behaviour (and hence bugs) within the mm subsystem. Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-08mm: fix cache mode tracking in vm_insert_mixed()Dan Williams1-2/+6
vm_insert_mixed() unlike vm_insert_pfn_prot() and vmf_insert_pfn_pmd(), fails to check the pgprot_t it uses for the mapping against the one recorded in the memtype tracking tree. Add the missing call to track_pfn_insert() to preclude cases where incompatible aliased mappings are established for a given physical address range. Link: http://lkml.kernel.org/r/147328717909.35069.14256589123570653697.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Cc: David Airlie <airlied@linux.ie> Cc: Matthew Wilcox <mawilcox@microsoft.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-08mm: make sure that kthreads will not refault oom reaped memoryMichal Hocko1-0/+13
There are only few use_mm() users in the kernel right now. Most of them write to the target memory but vhost driver relies on copy_from_user/get_user from a kernel thread context. This makes it impossible to reap the memory of an oom victim which shares the mm with the vhost kernel thread because it could see a zero page unexpectedly and theoretically make an incorrect decision visible outside of the killed task context. To quote Michael S. Tsirkin: : Getting an error from __get_user and friends is handled gracefully. : Getting zero instead of a real value will cause userspace : memory corruption. The vhost kernel thread is bound to an open fd of the vhost device which is not tight to the mm owner life cycle in general. The device fd can be inherited or passed over to another process which means that we really have to be careful about unexpected memory corruption because unlike for normal oom victims the result will be visible outside of the oom victim context. Make sure that no kthread context (users of use_mm) can ever see corrupted data because of the oom reaper and hook into the page fault path by checking MMF_UNSTABLE mm flag. __oom_reap_task_mm will set the flag before it starts unmapping the address space while the flag is checked after the page fault has been handled. If the flag is set then SIGBUS is triggered so any g-u-p user will get a error code. Regular tasks do not need this protection because all which share the mm are killed when the mm is reaped and so the corruption will not outlive them. This patch shouldn't have any visible effect at this moment because the OOM killer doesn't invoke oom reaper for tasks with mm shared with kthreads yet. Link: http://lkml.kernel.org/r/1472119394-11342-9-git-send-email-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: "Michael S. Tsirkin" <mst@redhat.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Oleg Nesterov <oleg@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-30Merge branch 'linus' into sched/core, to pick up fixesIngo Molnar1-5/+7
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-26mm: check VMA flags to avoid invalid PROT_NONE NUMA balancingLorenzo Stoakes1-5/+7
The NUMA balancing logic uses an arch-specific PROT_NONE page table flag defined by pte_protnone() or pmd_protnone() to mark PTEs or huge page PMDs respectively as requiring balancing upon a subsequent page fault. User-defined PROT_NONE memory regions which also have this flag set will not normally invoke the NUMA balancing code as do_page_fault() will send a segfault to the process before handle_mm_fault() is even called. However if access_remote_vm() is invoked to access a PROT_NONE region of memory, handle_mm_fault() is called via faultin_page() and __get_user_pages() without any access checks being performed, meaning the NUMA balancing logic is incorrectly invoked on a non-NUMA memory region. A simple means of triggering this problem is to access PROT_NONE mmap'd memory using /proc/self/mem which reliably results in the NUMA handling functions being invoked when CONFIG_NUMA_BALANCING is set. This issue was reported in bugzilla (issue 99101) which includes some simple repro code. There are BUG_ON() checks in do_numa_page() and do_huge_pmd_numa_page() added at commit c0e7cad to avoid accidentally provoking strange behaviour by attempting to apply NUMA balancing to pages that are in fact PROT_NONE. The BUG_ON()'s are consistently triggered by the repro. This patch moves the PROT_NONE check into mm/memory.c rather than invoking BUG_ON() as faulting in these pages via faultin_page() is a valid reason for reaching the NUMA check with the PROT_NONE page table flag set and is therefore not always a bug. Link: https://bugzilla.kernel.org/show_bug.cgi?id=99101 Reported-by: Trevor Saunders <tbsaunde@tbsaunde.org> Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Mel Gorman <mgorman@techsingularity.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-13sched/numa, mm: Revert to checking pmd/pte_write instead of VMA flagsRik van Riel1-1/+1
Commit: 4d9424669946 ("mm: convert p[te|md]_mknonnuma and remaining page table manipulations") changed NUMA balancing from _PAGE_NUMA to using PROT_NONE, and was quickly found to introduce a regression with NUMA grouping. It was followed up by these commits: 53da3bc2ba9e ("mm: fix up numa read-only thread grouping logic") bea66fbd11af ("mm: numa: group related processes based on VMA flags instead of page table flags") b191f9b106ea ("mm: numa: preserve PTE write permissions across a NUMA hinting fault") The first of those two commits try alternate approaches to NUMA grouping, which apparently do not work as well as looking at the PTE write permissions. The latter patch preserves the PTE write permissions across a NUMA protection fault. However, it forgets to revert the condition for whether or not to group tasks together back to what it was before v3.19, even though the information is now preserved in the page tables once again. This patch brings the NUMA grouping heuristic back to what it was before commit 4d9424669946, which the changelogs of subsequent commits suggest worked best. We have all the information again. We should probably use it. Signed-off-by: Rik van Riel <riel@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: aarcange@redhat.com Cc: linux-mm@kvack.org Cc: mgorman@suse.de Link: http://lkml.kernel.org/r/20160908213053.07c992a9@annuminas.surriel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-03mm: move swap-in anonymous page into active listMinchan Kim1-0/+1
Every swap-in anonymous page starts from inactive lru list's head. It should be activated unconditionally when VM decide to reclaim because page table entry for the page always usually has marked accessed bit. Thus, their window size for getting a new referece is 2 * NR_inactive + NR_active while others is NR_inactive + NR_active. It's not fair that it has more chance to be referenced compared to other newly allocated page which starts from active lru list's head. Johannes: : The page can still have a valid copy on the swap device, so prefering to : reclaim that page over a fresh one could make sense. But as you point : out, having it start inactive instead of active actually ends up giving it : *more* LRU time, and that seems to be without justification. Rik: : The reason newly read in swap cache pages start on the inactive list is : that we do some amount of read-around, and do not know which pages will : get used. : : However, immediately activating the ones that DO get used, like your patch : does, is the right thing to do. Link: http://lkml.kernel.org/r/1469762740-17860-1-git-send-email-minchan@kernel.org Signed-off-by: Minchan Kim <minchan@kernel.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Rik van Riel <riel@redhat.com> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Mel Gorman <mgorman@techsingularity.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>