92855270ff
14226 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Kaitao Cheng
|
92855270ff |
mm/memcontrol.c: cleanup some useless code
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.com Signed-off-by: Kaitao Cheng <pilgrimtao@gmail.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Vasily Averin
|
10c8d69f31 |
mm/swapfile.c: swap_next should increase position index
If seq_file .next fuction does not change position index, read after some lseek can generate unexpected output. In Aug 2018 NeilBrown noticed commit |
||
John Hubbard
|
f1f6a7dd9b |
mm, tree-wide: rename put_user_page*() to unpin_user_page*()
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.com Signed-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: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
John Hubbard
|
bdffe23eee |
mm/gup_benchmark: use proper FOLL_WRITE flags instead of hard-coding "1"
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.com Signed-off-by: John Hubbard <jhubbard@nvidia.com> Reviewed-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: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
John Hubbard
|
803e4572d7 |
mm/process_vm_access: set FOLL_PIN via pin_user_pages_remote()
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.com Signed-off-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Jérôme Glisse <jglisse@redhat.com> Reviewed-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: Jason Gunthorpe <jgg@mellanox.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> 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: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
John Hubbard
|
eddb1c228f |
mm/gup: introduce pin_user_pages*() and FOLL_PIN
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.com
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com> [Documentation]
Reviewed-by: Jérôme Glisse <jglisse@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
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: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Leon Romanovsky <leonro@mellanox.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
||
|
John Hubbard
|
f4000fdf43 |
mm/gup: allow FOLL_FORCE for get_user_pages_fast()
Commit |
||
|
John Hubbard
|
c4237f8b1f |
mm: fix get_user_pages_remote()'s handling of FOLL_LONGTERM
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.com
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Suggested-by: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
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: Leon Romanovsky <leonro@mellanox.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
||
|
John Hubbard
|
07d8026995 |
mm: devmap: refactor 1-based refcounting for ZONE_DEVICE pages
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.com Signed-off-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: John Hubbard <jhubbard@nvidia.com> Suggested-by: Jérôme Glisse <jglisse@redhat.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Christoph Hellwig <hch@lst.de> Cc: Kirill A. Shutemov <kirill@shutemov.name> 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: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Leon Romanovsky <leonro@mellanox.com> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Dan Williams
|
429589d647 |
mm: Cleanup __put_devmap_managed_page() vs ->page_free()
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.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jérôme Glisse <jglisse@redhat.com> Cc: Jan Kara <jack@suse.cz> 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: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> 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: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
John Hubbard
|
a707cdd55f |
mm/gup: move try_get_compound_head() to top, fix minor issues
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.com Signed-off-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-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: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl> 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: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
John Hubbard
|
a43e982082 |
mm/gup: factor out duplicate code from four routines
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.com
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jérôme Glisse <jglisse@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Björn Töpel <bjorn.topel@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Leon Romanovsky <leonro@mellanox.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
||
Wei Yang
|
be9d304589 |
mm/gup.c: use is_vm_hugetlb_page() to check whether to follow huge
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.com Signed-off-by: Wei Yang <richardw.yang@linux.intel.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: David Rientjes <rientjes@google.com> Reviewed-by: Ralph Campbell <rcampbell@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Qiujun Huang
|
15494520b7 |
mm: fix gup_pud_range
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.com Signed-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: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Ira Weiny
|
ddf8f376d1 |
mm/filemap.c: clean up filemap_write_and_wait()
At some point filemap_write_and_wait() and filemap_write_and_wait_range() got the exact same implementation with the exception of the range being specified in *_range() Similar to other functions in fs.h which call *_range(..., 0, LLONG_MAX), change filemap_write_and_wait() to be a static inline which calls filemap_write_and_wait_range() Link: http://lkml.kernel.org/r/20191129160713.30892-1-ira.weiny@intel.com Signed-off-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Vlastimil Babka
|
5b57b8f227 |
mm/debug.c: always print flags in dump_page()
Commit |
||
He Zhe
|
8c96f1bc6f |
mm/kmemleak: turn kmemleak_lock and object->lock to raw_spinlock_t
kmemleak_lock as a rwlock on RT can possibly be acquired in atomic context which does work. Since the kmemleak operation is performed in atomic context make it a raw_spinlock_t so it can also be acquired on RT. This is used for debugging and is not enabled by default in a production like environment (where performance/latency matters) so it makes sense to make it a raw_spinlock_t instead trying to get rid of the atomic context. Turn also the kmemleak_object->lock into raw_spinlock_t which is acquired (nested) while the kmemleak_lock is held. The time spent in "echo scan > kmemleak" slightly improved on 64core box with this patch applied after boot. [bigeasy@linutronix.de: redo the description, update comments. Merge the individual bits: He Zhe did the kmemleak_lock, Liu Haitao the ->lock and Yongxin Liu forwarded Liu's patch.] Link: http://lkml.kernel.org/r/20191219170834.4tah3prf2gdothz4@linutronix.de Link: https://lkml.kernel.org/r/20181218150744.GB20197@arrakis.emea.arm.com Link: https://lkml.kernel.org/r/1542877459-144382-1-git-send-email-zhe.he@windriver.com Link: https://lkml.kernel.org/r/20190927082230.34152-1-yongxin.liu@windriver.com Signed-off-by: He Zhe <zhe.he@windriver.com> Signed-off-by: Liu Haitao <haitao.liu@windriver.com> Signed-off-by: Yongxin Liu <yongxin.liu@windriver.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Yu Zhao
|
90e9f6a66c |
mm/slub.c: avoid slub allocation while holding list_lock
If we are already under list_lock, don't call kmalloc(). Otherwise we
will run into a deadlock because kmalloc() also tries to grab the same
lock.
Fix the problem by using a static bitmap instead.
WARNING: possible recursive locking detected
--------------------------------------------
mount-encrypted/4921 is trying to acquire lock:
(&(&n->list_lock)->rlock){-.-.}, at: ___slab_alloc+0x104/0x437
but task is already holding lock:
(&(&n->list_lock)->rlock){-.-.}, at: __kmem_cache_shutdown+0x81/0x3cb
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&(&n->list_lock)->rlock);
lock(&(&n->list_lock)->rlock);
*** DEADLOCK ***
Link: http://lkml.kernel.org/r/20191108193958.205102-2-yuzhao@google.com
Signed-off-by: Yu Zhao <yuzhao@google.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
||
Yang Shi
|
5984fabb6e |
mm: move_pages: report the number of non-attempted pages
Since commit |
||
|
Wei Yang
|
fac0516b55 |
mm: thp: don't need care deferred split queue in memcg charge move path
If compound is true, this means it is a PMD mapped THP. Which implies
the page is not linked to any defer list. So the first code chunk will
not be executed.
Also with this reason, it would not be proper to add this page to a
defer list. So the second code chunk is not correct.
Based on this, we should remove the defer list related code.
[yang.shi@linux.alibaba.com: better patch title]
Link: http://lkml.kernel.org/r/20200117233836.3434-1-richardw.yang@linux.intel.com
Fixes:
|
||
|
Dan Williams
|
f1037ec0cc |
mm/memory_hotplug: fix remove_memory() lockdep splat
The daxctl unit test for the dax_kmem driver currently triggers the
(false positive) lockdep splat below. It results from the fact that
remove_memory_block_devices() is invoked under the mem_hotplug_lock()
causing lockdep entanglements with cpu_hotplug_lock() and sysfs (kernfs
active state tracking). It is a false positive because the sysfs
attribute path triggering the memory remove is not the same attribute
path associated with memory-block device.
sysfs_break_active_protection() is not applicable since there is no real
deadlock conflict, instead move memory-block device removal outside the
lock. The mem_hotplug_lock() is not needed to synchronize the
memory-block device removal vs the page online state, that is already
handled by lock_device_hotplug(). Specifically, lock_device_hotplug()
is sufficient to allow try_remove_memory() to check the offline state of
the memblocks and be assured that any in progress online attempts are
flushed / blocked by kernfs_drain() / attribute removal.
The add_memory() path safely creates memblock devices under the
mem_hotplug_lock(). There is no kernfs active state synchronization in
the memblock device_register() path, so nothing to fix there.
This change is only possible thanks to the recent change that refactored
memory block device removal out of arch_remove_memory() (commit
|
||
|
Wei Yang
|
dfe9aa23ca |
mm/migrate.c: also overwrite error when it is bigger than zero
If we get here after successfully adding page to list, err would be 1 to
indicate the page is queued in the list.
Current code has two problems:
* on success, 0 is not returned
* on error, if add_page_for_migratioin() return 1, and the following err1
from do_move_pages_to_node() is set, the err1 is not returned since err
is 1
And these behaviors break the user interface.
Link: http://lkml.kernel.org/r/20200119065753.21694-1-richardw.yang@linux.intel.com
Fixes:
|
||
Pingfan Liu
|
1f503443e7 |
mm/sparse.c: reset section's mem_map when fully deactivated
After commit
|
||
Dan Carpenter
|
c7a91bc7c2 |
mm/mempolicy.c: fix out of bounds write in mpol_parse_str()
What we are trying to do is change the '=' character to a NUL terminator
and then at the end of the function we restore it back to an '='. The
problem is there are two error paths where we jump to the end of the
function before we have replaced the '=' with NUL.
We end up putting the '=' in the wrong place (possibly one element
before the start of the buffer).
Link: http://lkml.kernel.org/r/20200115055426.vdjwvry44nfug7yy@kili.mountain
Reported-by: syzbot+e64a13c5369a194d67df@syzkaller.appspotmail.com
Fixes:
|
||
Theodore Ts'o
|
68f23b8906 |
memcg: fix a crash in wb_workfn when a device disappears
Without memcg, there is a one-to-one mapping between the bdi and bdi_writeback structures. In this world, things are fairly straightforward; the first thing bdi_unregister() does is to shutdown the bdi_writeback structure (or wb), and part of that writeback ensures that no other work queued against the wb, and that the wb is fully drained. With memcg, however, there is a one-to-many relationship between the bdi and bdi_writeback structures; that is, there are multiple wb objects which can all point to a single bdi. There is a refcount which prevents the bdi object from being released (and hence, unregistered). So in theory, the bdi_unregister() *should* only get called once its refcount goes to zero (bdi_put will drop the refcount, and when it is zero, release_bdi gets called, which calls bdi_unregister). Unfortunately, del_gendisk() in block/gen_hd.c never got the memo about the Brave New memcg World, and calls bdi_unregister directly. It does this without informing the file system, or the memcg code, or anything else. This causes the root wb associated with the bdi to be unregistered, but none of the memcg-specific wb's are shutdown. So when one of these wb's are woken up to do delayed work, they try to dereference their wb->bdi->dev to fetch the device name, but unfortunately bdi->dev is now NULL, thanks to the bdi_unregister() called by del_gendisk(). As a result, *boom*. Fortunately, it looks like the rest of the writeback path is perfectly happy with bdi->dev and bdi->owner being NULL, so the simplest fix is to create a bdi_dev_name() function which can handle bdi->dev being NULL. This also allows us to bulletproof the writeback tracepoints to prevent them from dereferencing a NULL pointer and crashing the kernel if one is tracing with memcg's enabled, and an iSCSI device dies or a USB storage stick is pulled. The most common way of triggering this will be hotremoval of a device while writeback with memcg enabled is going on. It was triggering several times a day in a heavily loaded production environment. Google Bug Id: 145475544 Link: https://lore.kernel.org/r/20191227194829.150110-1-tytso@mit.edu Link: http://lkml.kernel.org/r/20191228005211.163952-1-tytso@mit.edu Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: Chris Mason <clm@fb.com> Cc: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Linus Torvalds
|
39bed42de2 |
hmm related patches for 5.6
This small series revises the names in mmu_notifier to make the code clearer and more readable. -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEfB7FMLh+8QxL+6i3OG33FX4gmxoFAl4wf2EACgkQOG33FX4g mxqrdw//XIexbXQqP4dUKFCFeI7Um6ZqYE6iVCQi6JEetpKxCR8BSrJsq6EP60Mg cVCKolISuudzOccz/liotg9SrwRlcO3mzucd8LJZG0v2FZMzQr0EKjst0RC4/xvK U2RxGvwLQ+XVR/3/l6hXyWyw7u28+F1RsfQMMX3kqR3qlcQachQ3k7oUINDIq2XH JkQcBV+XK0doXEp6VCCVKwuwEN7O5xSm8lAIHDNFZEEPre0iKxwatgWxdXFIWQek tRywwB7bRzFROBlDcoOQ0GDTqScr3bghz6vWU4GGv3avYkystKwy44ha6BzO2xQc ZNIo8AN9UFFhcmF531wklsXTCbxbxJAJAwdyIuQnKq5glw64EFnrjo2sxuL6s56h C1GHADtxDccv+nr2sKP/rFFeq9K3VqHDtjEdBOhReuB0Vp1YfVr17A4R8yAn8A+1 vm3IusoOq+g8qMYxRHEb+76/S//joaxAlFQkU5Gjn/0xsykP99YQSQFBjXmkzWlS IiHLf0HJiCCL8SHe4Wnyhyl1DUIIl38HQULqbFWZ8hK4ELhTd2KEuDxzT8q+v+v7 2M9nBVdRaw1kskGiFv+F7mb6c990CTEZO9B5fHpAjPRxeVkLYc06QfJY+hXbbu4c 6yzIvERRRlAviCmgb7G+3pLyBCKdvlIlCVsVOdxHXSRsl904BnA= =hhT0 -----END PGP SIGNATURE----- Merge tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma Pull mmu_notifier updates from Jason Gunthorpe: "This small series revises the names in mmu_notifier to make the code clearer and more readable" * tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: mm/mmu_notifiers: Use 'interval_sub' as the variable for mmu_interval_notifier mm/mmu_notifiers: Use 'subscription' as the variable name for mmu_notifier mm/mmu_notifier: Rename struct mmu_notifier_mm to mmu_notifier_subscriptions |
||
|
Linus Torvalds
|
896f8d23d0 |
for-5.6/io_uring-vfs-2020-01-29
-----BEGIN PGP SIGNATURE----- iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAl4yEegQHGF4Ym9lQGtl cm5lbC5kawAKCRD301j7KXHgpn5ZD/4/WlXs2cUDgg1C65bzZFO4qvevm+VkXmsk GbyrnFstRekvSH01/ZQxlyDVKS8Wux0XIJ6OArCh1047LvL1bEE5dvOW5iIiwa/r grjQuwFAzIPsE2fgcAO17BKIUzq2Z96+hwDzH7dw0i32yBuLvNmY/1SxcCHKfPut uzGyp7t3/2dIHbpWILRndMYe0O9j9ubmOMvKyKTwy723yDEafsUoqu2mlpigzTq4 2i+DbYBIAd8qmLqG/m3e+vOt9xodJ2Q0hlO+v6DcP2SKXU64Hb/N98HadR//aWP9 41DBXqs+dvDBcu3Jxb80PFUTiOQZECJivkns5cNcjuSXmNkOuQhDQR5K372AHmR9 m6e6FSBxwej8HselAZCI6yu9uBKd0i+MM4FnFs/O73QGYx2ayXsEXp/Jad9xiYgW pC5XJTSqJQhPE0AYYEOzHPPcBLBcpvXHkvmGKdjkNb8OLhhgh2S/YG0DNC+8ABXr j1uIe/n3kJEEmOanUyiitGyLmDq+mXd7aCVKJL/J0KiGD8Gkc1avAZ1ZrTQgjujY FqqBFawO8gv3g0L4WMI8JI+HJGMnA488obet6UKm9+l/Z/urEpXzDAKf/W/vnx2B LD0FSA0bCh1tyO6JU+avFwHlwShtV7/rx/OhrmCK7CCYKtZCA2IEctxyr8U+PBIv DtwIMTYTsA== =ZZUI -----END PGP SIGNATURE----- Merge tag 'for-5.6/io_uring-vfs-2020-01-29' of git://git.kernel.dk/linux-block Pull io_uring updates from Jens Axboe: - Support for various new opcodes (fallocate, openat, close, statx, fadvise, madvise, openat2, non-vectored read/write, send/recv, and epoll_ctl) - Faster ring quiesce for fileset updates - Optimizations for overflow condition checking - Support for max-sized clamping - Support for probing what opcodes are supported - Support for io-wq backend sharing between "sibling" rings - Support for registering personalities - Lots of little fixes and improvements * tag 'for-5.6/io_uring-vfs-2020-01-29' of git://git.kernel.dk/linux-block: (64 commits) io_uring: add support for epoll_ctl(2) eventpoll: support non-blocking do_epoll_ctl() calls eventpoll: abstract out epoll_ctl() handler io_uring: fix linked command file table usage io_uring: support using a registered personality for commands io_uring: allow registering credentials io_uring: add io-wq workqueue sharing io-wq: allow grabbing existing io-wq io_uring/io-wq: don't use static creds/mm assignments io-wq: make the io_wq ref counted io_uring: fix refcounting with batched allocations at OOM io_uring: add comment for drain_next io_uring: don't attempt to copy iovec for READ/WRITE io_uring: honor IOSQE_ASYNC for linked reqs io_uring: prep req when do IOSQE_ASYNC io_uring: use labeled array init in io_op_defs io_uring: optimise sqe-to-req flags translation io_uring: remove REQ_F_IO_DRAINED io_uring: file switch work needs to get flushed on exit io_uring: hide uring_fd in ctx ... |
||
|
Linus Torvalds
|
81a046b18b |
for-5.6-tag
-----BEGIN PGP SIGNATURE-----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=4OkE
-----END PGP SIGNATURE-----
Merge tag 'for-5.6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs updates from David Sterba:
"Features, highlights:
- async discard
- "mount -o discard=async" to enable it
- freed extents are not discarded immediatelly, but grouped
together and trimmed later, with IO rate limiting
- the "sync" mode submits short extents that could have been
ignored completely by the device, for SATA prior to 3.1 the
requests are unqueued and have a big impact on performance
- the actual discard IO requests have been moved out of
transaction commit to a worker thread, improving commit latency
- IO rate and request size can be tuned by sysfs files, for now
enabled only with CONFIG_BTRFS_DEBUG as we might need to
add/delete the files and don't have a stable-ish ABI for
general use, defaults are conservative
- export device state info in sysfs, eg. missing, writeable
- no discard of extents known to be untouched on disk (eg. after
reservation)
- device stats reset is logged with process name and PID that called
the ioctl
Fixes:
- fix missing hole after hole punching and fsync when using NO_HOLES
- writeback: range cyclic mode could miss some dirty pages and lead
to OOM
- two more corner cases for metadata_uuid change after power loss
during the change
- fix infinite loop during fsync after mix of rename operations
Core changes:
- qgroup assign returns ENOTCONN when quotas not enabled, used to
return EINVAL that was confusing
- device closing does not need to allocate memory anymore
- snapshot aware code got removed, disabled for years due to
performance problems, reimplmentation will allow to select wheter
defrag breaks or does not break COW on shared extents
- tree-checker:
- check leaf chunk item size, cross check against number of
stripes
- verify location keys for DIR_ITEM, DIR_INDEX and XATTR items
- new self test for physical -> logical mapping code, used for super
block range exclusion
- assertion helpers/macros updated to avoid objtool "unreachable
code" reports on older compilers or config option combinations"
* tag 'for-5.6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (84 commits)
btrfs: free block groups after free'ing fs trees
btrfs: Fix split-brain handling when changing FSID to metadata uuid
btrfs: Handle another split brain scenario with metadata uuid feature
btrfs: Factor out metadata_uuid code from find_fsid.
btrfs: Call find_fsid from find_fsid_inprogress
Btrfs: fix infinite loop during fsync after rename operations
btrfs: set trans->drity in btrfs_commit_transaction
btrfs: drop log root for dropped roots
btrfs: sysfs, add devid/dev_state kobject and device attributes
btrfs: Refactor btrfs_rmap_block to improve readability
btrfs: Add self-tests for btrfs_rmap_block
btrfs: selftests: Add support for dummy devices
btrfs: Move and unexport btrfs_rmap_block
btrfs: separate definition of assertion failure handlers
btrfs: device stats, log when stats are zeroed
btrfs: fix improper setting of scanned for range cyclic write cache pages
btrfs: safely advance counter when looking up bio csums
btrfs: remove unused member btrfs_device::work
btrfs: remove unnecessary wrapper get_alloc_profile
btrfs: add correction to handle -1 edge case in async discard
...
|
||
|
Linus Torvalds
|
f6170f0afb |
Merge branch 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull misc x86 updates from Ingo Molnar:
"Misc changes:
- Enhance #GP fault printouts by distinguishing between canonical and
non-canonical address faults, and also add KASAN fault decoding.
- Fix/enhance the x86 NMI handler by putting the duration check into
a direct function call instead of an irq_work which we know to be
broken in some cases.
- Clean up do_general_protection() a bit"
* 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/nmi: Remove irq_work from the long duration NMI handler
x86/traps: Cleanup do_general_protection()
x86/kasan: Print original address on #GP
x86/dumpstack: Introduce die_addr() for die() with #GP fault address
x86/traps: Print address on #GP
x86/insn-eval: Add support for 64-bit kernel mode
|
||
|
Linus Torvalds
|
c677124e63 |
Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
"These were the main changes in this cycle:
- More -rt motivated separation of CONFIG_PREEMPT and
CONFIG_PREEMPTION.
- Add more low level scheduling topology sanity checks and warnings
to filter out nonsensical topologies that break scheduling.
- Extend uclamp constraints to influence wakeup CPU placement
- Make the RT scheduler more aware of asymmetric topologies and CPU
capacities, via uclamp metrics, if CONFIG_UCLAMP_TASK=y
- Make idle CPU selection more consistent
- Various fixes, smaller cleanups, updates and enhancements - please
see the git log for details"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits)
sched/fair: Define sched_idle_cpu() only for SMP configurations
sched/topology: Assert non-NUMA topology masks don't (partially) overlap
idle: fix spelling mistake "iterrupts" -> "interrupts"
sched/fair: Remove redundant call to cpufreq_update_util()
sched/psi: create /proc/pressure and /proc/pressure/{io|memory|cpu} only when psi enabled
sched/fair: Fix sgc->{min,max}_capacity calculation for SD_OVERLAP
sched/fair: calculate delta runnable load only when it's needed
sched/cputime: move rq parameter in irqtime_account_process_tick
stop_machine: Make stop_cpus() static
sched/debug: Reset watchdog on all CPUs while processing sysrq-t
sched/core: Fix size of rq::uclamp initialization
sched/uclamp: Fix a bug in propagating uclamp value in new cgroups
sched/fair: Load balance aggressively for SCHED_IDLE CPUs
sched/fair : Improve update_sd_pick_busiest for spare capacity case
watchdog: Remove soft_lockup_hrtimer_cnt and related code
sched/rt: Make RT capacity-aware
sched/fair: Make EAS wakeup placement consider uclamp restrictions
sched/fair: Make task_fits_capacity() consider uclamp restrictions
sched/uclamp: Rename uclamp_util_with() into uclamp_rq_util_with()
sched/uclamp: Make uclamp util helpers use and return UL values
...
|
||
|
Linus Torvalds
|
634cd4b6af |
Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI updates from Ingo Molnar:
"The main changes in this cycle were:
- Cleanup of the GOP [graphics output] handling code in the EFI stub
- Complete refactoring of the mixed mode handling in the x86 EFI stub
- Overhaul of the x86 EFI boot/runtime code
- Increase robustness for mixed mode code
- Add the ability to disable DMA at the root port level in the EFI
stub
- Get rid of RWX mappings in the EFI memory map and page tables,
where possible
- Move the support code for the old EFI memory mapping style into its
only user, the SGI UV1+ support code.
- plus misc fixes, updates, smaller cleanups.
... and due to interactions with the RWX changes, another round of PAT
cleanups make a guest appearance via the EFI tree - with no side
effects intended"
* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (75 commits)
efi/x86: Disable instrumentation in the EFI runtime handling code
efi/libstub/x86: Fix EFI server boot failure
efi/x86: Disallow efi=old_map in mixed mode
x86/boot/compressed: Relax sed symbol type regex for LLVM ld.lld
efi/x86: avoid KASAN false positives when accessing the 1: 1 mapping
efi: Fix handling of multiple efi_fake_mem= entries
efi: Fix efi_memmap_alloc() leaks
efi: Add tracking for dynamically allocated memmaps
efi: Add a flags parameter to efi_memory_map
efi: Fix comment for efi_mem_type() wrt absent physical addresses
efi/arm: Defer probe of PCIe backed efifb on DT systems
efi/x86: Limit EFI old memory map to SGI UV machines
efi/x86: Avoid RWX mappings for all of DRAM
efi/x86: Don't map the entire kernel text RW for mixed mode
x86/mm: Fix NX bit clearing issue in kernel_map_pages_in_pgd
efi/libstub/x86: Fix unused-variable warning
efi/libstub/x86: Use mandatory 16-byte stack alignment in mixed mode
efi/libstub/x86: Use const attribute for efi_is_64bit()
efi: Allow disabling PCI busmastering on bridges during boot
efi/x86: Allow translating 64-bit arguments for mixed mode calls
...
|
||
|
Linus Torvalds
|
ab67f60025 |
A small set of SMP core code changes:
- Rework the smp function call core code to avoid the allocation of an
additional cpumask.
- Remove the not longer required GFP argument from on_each_cpu_cond() and
on_each_cpu_cond_mask() and fixup the callers.
-----BEGIN PGP SIGNATURE-----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=M4aK
-----END PGP SIGNATURE-----
Merge tag 'smp-core-2020-01-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull core SMP updates from Thomas Gleixner:
"A small set of SMP core code changes:
- Rework the smp function call core code to avoid the allocation of
an additional cpumask
- Remove the not longer required GFP argument from on_each_cpu_cond()
and on_each_cpu_cond_mask() and fixup the callers"
* tag 'smp-core-2020-01-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
smp: Remove allocation mask from on_each_cpu_cond.*()
smp: Add a smp_cond_func_t argument to smp_call_function_many()
smp: Use smp_cond_func_t as type for the conditional function
|
||
|
Linus Torvalds
|
e279160f49 |
The timekeeping and timers departement provides:
- Time namespace support:
If a container migrates from one host to another then it expects that
clocks based on MONOTONIC and BOOTTIME are not subject to
disruption. Due to different boot time and non-suspended runtime these
clocks can differ significantly on two hosts, in the worst case time
goes backwards which is a violation of the POSIX requirements.
The time namespace addresses this problem. It allows to set offsets for
clock MONOTONIC and BOOTTIME once after creation and before tasks are
associated with the namespace. These offsets are taken into account by
timers and timekeeping including the VDSO.
Offsets for wall clock based clocks (REALTIME/TAI) are not provided by
this mechanism. While in theory possible, the overhead and code
complexity would be immense and not justified by the esoteric potential
use cases which were discussed at Plumbers '18.
The overhead for tasks in the root namespace (host time offsets = 0) is
in the noise and great effort was made to ensure that especially in the
VDSO. If time namespace is disabled in the kernel configuration the
code is compiled out.
Kudos to Andrei Vagin and Dmitry Sofanov who implemented this feature
and kept on for more than a year addressing review comments, finding
better solutions. A pleasant experience.
- Overhaul of the alarmtimer device dependency handling to ensure that
the init/suspend/resume ordering is correct.
- A new clocksource/event driver for Microchip PIT64
- Suspend/resume support for the Hyper-V clocksource
- The usual pile of fixes, updates and improvements mostly in the
driver code.
-----BEGIN PGP SIGNATURE-----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=x3qT
-----END PGP SIGNATURE-----
Merge tag 'timers-core-2020-01-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
"The timekeeping and timers departement provides:
- Time namespace support:
If a container migrates from one host to another then it expects
that clocks based on MONOTONIC and BOOTTIME are not subject to
disruption. Due to different boot time and non-suspended runtime
these clocks can differ significantly on two hosts, in the worst
case time goes backwards which is a violation of the POSIX
requirements.
The time namespace addresses this problem. It allows to set offsets
for clock MONOTONIC and BOOTTIME once after creation and before
tasks are associated with the namespace. These offsets are taken
into account by timers and timekeeping including the VDSO.
Offsets for wall clock based clocks (REALTIME/TAI) are not provided
by this mechanism. While in theory possible, the overhead and code
complexity would be immense and not justified by the esoteric
potential use cases which were discussed at Plumbers '18.
The overhead for tasks in the root namespace (ie where host time
offsets = 0) is in the noise and great effort was made to ensure
that especially in the VDSO. If time namespace is disabled in the
kernel configuration the code is compiled out.
Kudos to Andrei Vagin and Dmitry Sofanov who implemented this
feature and kept on for more than a year addressing review
comments, finding better solutions. A pleasant experience.
- Overhaul of the alarmtimer device dependency handling to ensure
that the init/suspend/resume ordering is correct.
- A new clocksource/event driver for Microchip PIT64
- Suspend/resume support for the Hyper-V clocksource
- The usual pile of fixes, updates and improvements mostly in the
driver code"
* tag 'timers-core-2020-01-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (71 commits)
alarmtimer: Make alarmtimer_get_rtcdev() a stub when CONFIG_RTC_CLASS=n
alarmtimer: Use wakeup source from alarmtimer platform device
alarmtimer: Make alarmtimer platform device child of RTC device
alarmtimer: Update alarmtimer_get_rtcdev() docs to reflect reality
hrtimer: Add missing sparse annotation for __run_timer()
lib/vdso: Only read hrtimer_res when needed in __cvdso_clock_getres()
MIPS: vdso: Define BUILD_VDSO32 when building a 32bit kernel
clocksource/drivers/hyper-v: Set TSC clocksource as default w/ InvariantTSC
clocksource/drivers/hyper-v: Untangle stimers and timesync from clocksources
clocksource/drivers/timer-microchip-pit64b: Fix sparse warning
clocksource/drivers/exynos_mct: Rename Exynos to lowercase
clocksource/drivers/timer-ti-dm: Fix uninitialized pointer access
clocksource/drivers/timer-ti-dm: Switch to platform_get_irq
clocksource/drivers/timer-ti-dm: Convert to devm_platform_ioremap_resource
clocksource/drivers/em_sti: Fix variable declaration in em_sti_probe
clocksource/drivers/em_sti: Convert to devm_platform_ioremap_resource
clocksource/drivers/bcm2835_timer: Fix memory leak of timer
clocksource/drivers/cadence-ttc: Use ttc driver as platform driver
clocksource/drivers/timer-microchip-pit64b: Add Microchip PIT64B support
clocksource/drivers/hyper-v: Reserve PAGE_SIZE space for tsc page
...
|
||
|
Linus Torvalds
|
03aa8c8cfa |
Merge branch 'for-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo: - cgroup2 interface for hugetlb controller. I think this was the last remaining bit which was missing from cgroup2 - fixes for race and a spurious warning in threaded cgroup handling - other minor changes * 'for-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: iocost: Fix iocost_monitor.py due to helper type mismatch cgroup: Prevent double killing of css when enabling threaded cgroup cgroup: fix function name in comment mm: hugetlb controller for cgroups v2 |
||
Sebastian Andrzej Siewior
|
cb923159bb |
smp: Remove allocation mask from on_each_cpu_cond.*()
The allocation mask is no longer used by on_each_cpu_cond() and on_each_cpu_cond_mask() and can be removed. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20200117090137.1205765-4-bigeasy@linutronix.de |
||
Jens Axboe
|
db08ca2525 |
mm: make do_madvise() available internally
This is in preparation for enabling this functionality through io_uring. Add a helper that is just exporting what sys_madvise() does, and have the system call use it. No functional changes in this patch. Reviewed-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> |
||
Dennis Zhou
|
e837dfde15 |
bitmap: genericize percpu bitmap region iterators
Bitmaps are fairly popular for their space efficiency, but we don't have generic iterators available. Make percpu's bitmap region iterators available to everyone. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Dennis Zhou <dennis@kernel.org> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
||
Ingo Molnar
|
a786810cc8 |
Linux 5.5-rc7
-----BEGIN PGP SIGNATURE----- iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAl4k7i8eHHRvcnZhbGRz QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGvk0IAKRenVOdiudY77SQ VZjsteyrYTTQtPPv494ToIRjR0XQ+gYp8vyWzXTUC5Nm9Y9U3VzDqUPUjWszrSXE 6mU+tzcMc9qwuUxnIFn8zfg64ygw+37sn/w3xqeH4QmF9Z5Wl3EX3SdXTs7jp3RS VxiztkUNI5ZBV2GDtla5K/9qLPqCQnUYXIiyi5lAtBtiitZDVXFp7dy7hMgEiaEO +78K5Kh3xlt5ndDsBFOlwIb2Oof3KL7bBXntdbSBc/bjol6IRvAgln48HWCv59G2 jzAp2tj2KobX9GRAEPj+v4TQZEW0SXDNDi8MgQsM+3DYVCTmANsv57CBKRuf01+F nB1kAys= =zSnJ -----END PGP SIGNATURE----- Merge tag 'v5.5-rc7' into efi/core, to pick up fixes Signed-off-by: Ingo Molnar <mingo@kernel.org> |
||
Jason Gunthorpe
|
5292e24a6a |
mm/mmu_notifiers: Use 'interval_sub' as the variable for mmu_interval_notifier
The 'interval_sub' is placed on the 'notifier_subscriptions' interval tree. This eliminates the poor name 'mni' for this variable. Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> |
||
|
Jason Gunthorpe
|
1991722a70 |
mm/mmu_notifiers: Use 'subscription' as the variable name for mmu_notifier
The 'subscription' is placed on the 'notifier_subscriptions' list. This eliminates the poor name 'mn' for this variable. Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> |
||
|
Jason Gunthorpe
|
984cfe4e25 |
mm/mmu_notifier: Rename struct mmu_notifier_mm to mmu_notifier_subscriptions
The name mmu_notifier_mm implies that the thing is a mm_struct pointer, and is difficult to abbreviate. The struct is actually holding the interval tree and hlist containing the notifiers subscribed to a mm. Use 'subscriptions' as the variable name for this struct instead of the really terrible and misleading 'mmn_mm'. Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> |
||
Dmitry Safonov
|
af34ebeb86 |
x86/vdso: Handle faults on timens page
If a task belongs to a time namespace then the VVAR page which contains the system wide VDSO data is replaced with a namespace specific page which has the same layout as the VVAR page. Co-developed-by: Andrei Vagin <avagin@gmail.com> Signed-off-by: Andrei Vagin <avagin@gmail.com> Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20191112012724.250792-25-dima@arista.com |
||
Adrian Huang
|
2fe20210fc |
mm: memcg/slab: call flush_memcg_workqueue() only if memcg workqueue is valid
When booting with amd_iommu=off, the following WARNING message
appears:
AMD-Vi: AMD IOMMU disabled on kernel command-line
------------[ cut here ]------------
WARNING: CPU: 0 PID: 0 at kernel/workqueue.c:2772 flush_workqueue+0x42e/0x450
Modules linked in:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.5.0-rc3-amd-iommu #6
Hardware name: Lenovo ThinkSystem SR655-2S/7D2WRCZ000, BIOS D8E101L-1.00 12/05/2019
RIP: 0010:flush_workqueue+0x42e/0x450
Code: ff 0f 0b e9 7a fd ff ff 4d 89 ef e9 33 fe ff ff 0f 0b e9 7f fd ff ff 0f 0b e9 bc fd ff ff 0f 0b e9 a8 fd ff ff e8 52 2c fe ff <0f> 0b 31 d2 48 c7 c6 e0 88 c5 95 48 c7 c7 d8 ad f0 95 e8 19 f5 04
Call Trace:
kmem_cache_destroy+0x69/0x260
iommu_go_to_state+0x40c/0x5ab
amd_iommu_prepare+0x16/0x2a
irq_remapping_prepare+0x36/0x5f
enable_IR_x2apic+0x21/0x172
default_setup_apic_routing+0x12/0x6f
apic_intr_mode_init+0x1a1/0x1f1
x86_late_time_init+0x17/0x1c
start_kernel+0x480/0x53f
secondary_startup_64+0xb6/0xc0
---[ end trace 30894107c3749449 ]---
x2apic: IRQ remapping doesn't support X2APIC mode
x2apic disabled
The warning is caused by the calling of 'kmem_cache_destroy()'
in free_iommu_resources(). Here is the call path:
free_iommu_resources
kmem_cache_destroy
flush_memcg_workqueue
flush_workqueue
The root cause is that the IOMMU subsystem runs before the workqueue
subsystem, which the variable 'wq_online' is still 'false'. This leads
to the statement 'if (WARN_ON(!wq_online))' in flush_workqueue() is
'true'.
Since the variable 'memcg_kmem_cache_wq' is not allocated during the
time, it is unnecessary to call flush_memcg_workqueue(). This prevents
the WARNING message triggered by flush_workqueue().
Link: http://lkml.kernel.org/r/20200103085503.1665-1-ahuang12@lenovo.com
Fixes:
|
||
Wen Yang
|
0a5d1a7f64 |
mm/page-writeback.c: improve arithmetic divisions
Use div64_ul() instead of do_div() if the divisor is unsigned long, to avoid truncation to 32-bit on 64-bit platforms. Link: http://lkml.kernel.org/r/20200102081442.8273-4-wenyang@linux.alibaba.com Signed-off-by: Wen Yang <wenyang@linux.alibaba.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Qian Cai <cai@lca.pw> Cc: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Wen Yang
|
d3ac946ec9 |
mm/page-writeback.c: use div64_ul() for u64-by-unsigned-long divide
The two variables 'numerator' and 'denominator', though they are declared as long, they should actually be unsigned long (according to the implementation of the fprop_fraction_percpu() function) And do_div() does a 64-by-32 division, while the divisor 'denominator' is unsigned long, thus 64-bit on 64-bit platforms. Hence the proper function to call is div64_ul(). Link: http://lkml.kernel.org/r/20200102081442.8273-3-wenyang@linux.alibaba.com Signed-off-by: Wen Yang <wenyang@linux.alibaba.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Qian Cai <cai@lca.pw> Cc: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Wen Yang
|
6d9e8c651d |
mm/page-writeback.c: avoid potential division by zero in wb_min_max_ratio()
Patch series "use div64_ul() instead of div_u64() if the divisor is unsigned long". We were first inspired by commit |
||
|
Vlastimil Babka
|
8e57f8acbb |
mm, debug_pagealloc: don't rely on static keys too early
Commit |
||
Roman Gushchin
|
4a87e2a25d |
mm: memcg/slab: fix percpu slab vmstats flushing
Currently slab percpu vmstats are flushed twice: during the memcg
offlining and just before freeing the memcg structure. Each time percpu
counters are summed, added to the atomic counterparts and propagated up
by the cgroup tree.
The second flushing is required due to how recursive vmstats are
implemented: counters are batched in percpu variables on a local level,
and once a percpu value is crossing some predefined threshold, it spills
over to atomic values on the local and each ascendant levels. It means
that without flushing some numbers cached in percpu variables will be
dropped on floor each time a cgroup is destroyed. And with uptime the
error on upper levels might become noticeable.
The first flushing aims to make counters on ancestor levels more
precise. Dying cgroups may resume in the dying state for a long time.
After kmem_cache reparenting which is performed during the offlining
slab counters of the dying cgroup don't have any chances to be updated,
because any slab operations will be performed on the parent level. It
means that the inaccuracy caused by percpu batching will not decrease up
to the final destruction of the cgroup. By the original idea flushing
slab counters during the offlining should minimize the visible
inaccuracy of slab counters on the parent level.
The problem is that percpu counters are not zeroed after the first
flushing. So every cached percpu value is summed twice. It creates a
small error (up to 32 pages per cpu, but usually less) which accumulates
on parent cgroup level. After creating and destroying of thousands of
child cgroups, slab counter on parent level can be way off the real
value.
For now, let's just stop flushing slab counters on memcg offlining. It
can't be done correctly without scheduling a work on each cpu: reading
and zeroing it during css offlining can race with an asynchronous
update, which doesn't expect values to be changed underneath.
With this change, slab counters on parent level will become eventually
consistent. Once all dying children are gone, values are correct. And
if not, the error is capped by 32 * NR_CPUS pages per dying cgroup.
It's not perfect, as slab are reparented, so any updates after the
reparenting will happen on the parent level. It means that if a slab
page was allocated, a counter on child level was bumped, then the page
was reparented and freed, the annihilation of positive and negative
counter values will not happen until the child cgroup is released. It
makes slab counters different from others, and it might want us to
implement flushing in a correct form again. But it's also a question of
performance: scheduling a work on each cpu isn't free, and it's an open
question if the benefit of having more accurate counters is worth it.
We might also consider flushing all counters on offlining, not only slab
counters.
So let's fix the main problem now: make the slab counters eventually
consistent, so at least the error won't grow with uptime (or more
precisely the number of created and destroyed cgroups). And think about
the accuracy of counters separately.
Link: http://lkml.kernel.org/r/20191220042728.1045881-1-guro@fb.com
Fixes:
|
||
Kirill A. Shutemov
|
991589974d |
mm/shmem.c: thp, shmem: fix conflict of above-47bit hint address and PMD alignment
Shmem/tmpfs tries to provide THP-friendly mappings if huge pages are
enabled. But it doesn't work well with above-47bit hint address.
Normally, the kernel doesn't create userspace mappings above 47-bit,
even if the machine allows this (such as with 5-level paging on x86-64).
Not all user space is ready to handle wide addresses. It's known that
at least some JIT compilers use higher bits in pointers to encode their
information.
Userspace can ask for allocation from full address space by specifying
hint address (with or without MAP_FIXED) above 47-bits. If the
application doesn't need a particular address, but wants to allocate
from whole address space it can specify -1 as a hint address.
Unfortunately, this trick breaks THP alignment in shmem/tmp:
shmem_get_unmapped_area() would not try to allocate PMD-aligned area if
*any* hint address specified.
This can be fixed by requesting the aligned area if the we failed to
allocated at user-specified hint address. The request with inflated
length will also take the user-specified hint address. This way we will
not lose an allocation request from the full address space.
[kirill@shutemov.name: fold in a fixup]
Link: http://lkml.kernel.org/r/20191223231309.t6bh5hkbmokihpfu@box
Link: http://lkml.kernel.org/r/20191220142548.7118-3-kirill.shutemov@linux.intel.com
Fixes:
|
||
|
Kirill A. Shutemov
|
97d3d0f9a1 |
mm/huge_memory.c: thp: fix conflict of above-47bit hint address and PMD alignment
Patch series "Fix two above-47bit hint address vs. THP bugs".
The two get_unmapped_area() implementations have to be fixed to provide
THP-friendly mappings if above-47bit hint address is specified.
This patch (of 2):
Filesystems use thp_get_unmapped_area() to provide THP-friendly
mappings. For DAX in particular.
Normally, the kernel doesn't create userspace mappings above 47-bit,
even if the machine allows this (such as with 5-level paging on x86-64).
Not all user space is ready to handle wide addresses. It's known that
at least some JIT compilers use higher bits in pointers to encode their
information.
Userspace can ask for allocation from full address space by specifying
hint address (with or without MAP_FIXED) above 47-bits. If the
application doesn't need a particular address, but wants to allocate
from whole address space it can specify -1 as a hint address.
Unfortunately, this trick breaks thp_get_unmapped_area(): the function
would not try to allocate PMD-aligned area if *any* hint address
specified.
Modify the routine to handle it correctly:
- Try to allocate the space at the specified hint address with length
padding required for PMD alignment.
- If failed, retry without length padding (but with the same hint
address);
- If the returned address matches the hint address return it.
- Otherwise, align the address as required for THP and return.
The user specified hint address is passed down to get_unmapped_area() so
above-47bit hint address will be taken into account without breaking
alignment requirements.
Link: http://lkml.kernel.org/r/20191220142548.7118-2-kirill.shutemov@linux.intel.com
Fixes:
|