Commit Graph

786 Commits

Author SHA1 Message Date
Linus Torvalds
68abbe7295 Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:

 - a few misc things

 - ocfs2 updates

 - v9fs updates

 - MM

 - procfs updates

 - lib/ updates

 - autofs updates

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (118 commits)
  autofs: small cleanup in autofs_getpath()
  autofs: clean up includes
  autofs: comment on selinux changes needed for module autoload
  autofs: update MAINTAINERS entry for autofs
  autofs: use autofs instead of autofs4 in documentation
  autofs: rename autofs documentation files
  autofs: create autofs Kconfig and Makefile
  autofs: delete fs/autofs4 source files
  autofs: update fs/autofs4/Makefile
  autofs: update fs/autofs4/Kconfig
  autofs: copy autofs4 to autofs
  autofs4: use autofs instead of autofs4 everywhere
  autofs4: merge auto_fs.h and auto_fs4.h
  fs/binfmt_misc.c: do not allow offset overflow
  checkpatch: improve patch recognition
  lib/ucs2_string.c: add MODULE_LICENSE()
  lib/mpi: headers cleanup
  lib/percpu_ida.c: use _irqsave() instead of local_irq_save() + spin_lock
  lib/idr.c: remove simple_ida_lock
  lib/bitmap.c: micro-optimization for __bitmap_complement()
  ...
2018-06-07 18:39:37 -07:00
Laurent Dufour
00b3a331fd mm: remove odd HAVE_PTE_SPECIAL
Remove the additional define HAVE_PTE_SPECIAL and rely directly on
CONFIG_ARCH_HAS_PTE_SPECIAL.

There is no functional change introduced by this patch

Link: http://lkml.kernel.org/r/1523533733-25437-1-git-send-email-ldufour@linux.vnet.ibm.com
Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Acked-by: David Rientjes <rientjes@google.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Christophe LEROY <christophe.leroy@c-s.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-07 17:34:35 -07:00
Laurent Dufour
3010a5ea66 mm: introduce ARCH_HAS_PTE_SPECIAL
Currently the PTE special supports is turned on in per architecture
header files.  Most of the time, it is defined in
arch/*/include/asm/pgtable.h depending or not on some other per
architecture static definition.

This patch introduce a new configuration variable to manage this
directly in the Kconfig files.  It would later replace
__HAVE_ARCH_PTE_SPECIAL.

Here notes for some architecture where the definition of
__HAVE_ARCH_PTE_SPECIAL is not obvious:

arm
 __HAVE_ARCH_PTE_SPECIAL which is currently defined in
arch/arm/include/asm/pgtable-3level.h which is included by
arch/arm/include/asm/pgtable.h when CONFIG_ARM_LPAE is set.
So select ARCH_HAS_PTE_SPECIAL if ARM_LPAE.

powerpc
__HAVE_ARCH_PTE_SPECIAL is defined in 2 files:
 - arch/powerpc/include/asm/book3s/64/pgtable.h
 - arch/powerpc/include/asm/pte-common.h
The first one is included if (PPC_BOOK3S & PPC64) while the second is
included in all the other cases.
So select ARCH_HAS_PTE_SPECIAL all the time.

sparc:
__HAVE_ARCH_PTE_SPECIAL is defined if defined(__sparc__) &&
defined(__arch64__) which are defined through the compiler in
sparc/Makefile if !SPARC32 which I assume to be if SPARC64.
So select ARCH_HAS_PTE_SPECIAL if SPARC64

There is no functional change introduced by this patch.

Link: http://lkml.kernel.org/r/1523433816-14460-2-git-send-email-ldufour@linux.vnet.ibm.com
Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Suggested-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Albert Ou <albert@sifive.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Christophe LEROY <christophe.leroy@c-s.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-07 17:34:35 -07:00
Souptick Joarder
ab77dab462 fs/dax.c: use new return type vm_fault_t
Use new return type vm_fault_t for fault handler.  For now, this is just
documenting that the function returns a VM_FAULT value rather than an
errno.  Once all instances are converted, vm_fault_t will become a
distinct type.

commit 1c8f422059 ("mm: change return type to vm_fault_t")

There was an existing bug inside dax_load_hole() if vm_insert_mixed had
failed to allocate a page table, we'd return VM_FAULT_NOPAGE instead of
VM_FAULT_OOM.  With new vmf_insert_mixed() this issue is addressed.

vm_insert_mixed_mkwrite has inefficiency when it returns an error value,
driver has to convert it to vm_fault_t type.  With new
vmf_insert_mixed_mkwrite() this limitation will be addressed.

Link: http://lkml.kernel.org/r/20180510181121.GA15239@jordon-HP-15-Notebook-PC
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Michal Hocko <mhocko@suse.com>
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>
2018-06-07 17:34:33 -07:00
Leon Romanovsky
27d036e332 mm: Remove return value of zap_vma_ptes()
All callers of zap_vma_ptes() are not interested in the return value of
that function, so let's simplify its interface and drop the return
value.

Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2018-06-01 11:20:43 -04:00
Minchan Kim
e9e9b7ecee mm: swap: unify cluster-based and vma-based swap readahead
This patch makes do_swap_page() not need to be aware of two different
swap readahead algorithms.  Just unify cluster-based and vma-based
readahead function call.

Link: http://lkml.kernel.org/r/1509520520-32367-3-git-send-email-minchan@kernel.org
Link: http://lkml.kernel.org/r/20180220085249.151400-3-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05 21:36:25 -07:00
Minchan Kim
eaf649ebc3 mm: swap: clean up swap readahead
When I see recent change of swap readahead, I am very unhappy about
current code structure which diverges two swap readahead algorithm in
do_swap_page.  This patch is to clean it up.

Main motivation is that fault handler doesn't need to be aware of
readahead algorithms but just should call swapin_readahead.

As first step, this patch cleans up a little bit but not perfect (I just
separate for review easier) so next patch will make the goal complete.

[minchan@kernel.org: do not check readahead flag with THP anon]
  Link: http://lkml.kernel.org/r/874lm83zho.fsf@yhuang-dev.intel.com
  Link: http://lkml.kernel.org/r/20180227232611.169883-1-minchan@kernel.org
Link: http://lkml.kernel.org/r/1509520520-32367-2-git-send-email-minchan@kernel.org
Link: http://lkml.kernel.org/r/20180220085249.151400-2-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05 21:36:25 -07:00
Khalid Aziz
ca827d55eb mm, swap: Add infrastructure for saving page metadata on swap
If a processor supports special metadata for a page, for example ADI
version tags on SPARC M7, this metadata must be saved when the page is
swapped out. The same metadata must be restored when the page is swapped
back in. This patch adds two new architecture specific functions -
arch_do_swap_page() to be called when a page is swapped in, and
arch_unmap_one() to be called when a page is being unmapped for swap
out. These architecture hooks allow page metadata to be saved if the
architecture supports it.

Signed-off-by: Khalid Aziz <khalid.aziz@oracle.com>
Cc: Khalid Aziz <khalid@gonehiking.org>
Acked-by: Jerome Marchand <jmarchan@redhat.com>
Reviewed-by: Anthony Yznaga <anthony.yznaga@oracle.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-18 07:38:45 -07:00
Arnd Bergmann
af27d9403f mm: hide a #warning for COMPILE_TEST
We get a warning about some slow configurations in randconfig kernels:

  mm/memory.c:83:2: error: #warning Unfortunate NUMA and NUMA Balancing config, growing page-frame for last_cpupid. [-Werror=cpp]

The warning is reasonable by itself, but gets in the way of randconfig
build testing, so I'm hiding it whenever CONFIG_COMPILE_TEST is set.

The warning was added in 2013 in commit 75980e97da ("mm: fold
page->_last_nid into page->flags where possible").

Cc: stable@vger.kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-16 09:41:36 -08:00
Linus Torvalds
a2e5790d84 Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:

 - kasan updates

 - procfs

 - lib/bitmap updates

 - other lib/ updates

 - checkpatch tweaks

 - rapidio

 - ubsan

 - pipe fixes and cleanups

 - lots of other misc bits

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (114 commits)
  Documentation/sysctl/user.txt: fix typo
  MAINTAINERS: update ARM/QUALCOMM SUPPORT patterns
  MAINTAINERS: update various PALM patterns
  MAINTAINERS: update "ARM/OXNAS platform support" patterns
  MAINTAINERS: update Cortina/Gemini patterns
  MAINTAINERS: remove ARM/CLKDEV SUPPORT file pattern
  MAINTAINERS: remove ANDROID ION pattern
  mm: docs: add blank lines to silence sphinx "Unexpected indentation" errors
  mm: docs: fix parameter names mismatch
  mm: docs: fixup punctuation
  pipe: read buffer limits atomically
  pipe: simplify round_pipe_size()
  pipe: reject F_SETPIPE_SZ with size over UINT_MAX
  pipe: fix off-by-one error when checking buffer limits
  pipe: actually allow root to exceed the pipe buffer limits
  pipe, sysctl: remove pipe_proc_fn()
  pipe, sysctl: drop 'min' parameter from pipe-max-size converter
  kasan: rework Kconfig settings
  crash_dump: is_kdump_kernel can be boolean
  kernel/mutex: mutex_is_locked can be boolean
  ...
2018-02-06 22:15:42 -08:00
Sergey Senozhatsky
e7c98df598 mm: remove unneeded kallsyms include
The file was converted from print_symbol() to %pSR a while ago in commit
071361d347 ("mm: Convert print_symbol to %pSR").  kallsyms does not
seem to be needed anymore.

Link: http://lkml.kernel.org/r/20171208025616.16267-3-sergey.senozhatsky@gmail.com
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06 18:32:47 -08:00
Linus Torvalds
3ff1b28caa Merge tag 'libnvdimm-for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Ross Zwisler:

 - Require struct page by default for filesystem DAX to remove a number
   of surprising failure cases. This includes failures with direct I/O,
   gdb and fork(2).

 - Add support for the new Platform Capabilities Structure added to the
   NFIT in ACPI 6.2a. This new table tells us whether the platform
   supports flushing of CPU and memory controller caches on unexpected
   power loss events.

 - Revamp vmem_altmap and dev_pagemap handling to clean up code and
   better support future future PCI P2P uses.

 - Deprecate the ND_IOCTL_SMART_THRESHOLD command whose payload has
   become out-of-sync with recent versions of the NVDIMM_FAMILY_INTEL
   spec, and instead rely on the generic ND_CMD_CALL approach used by
   the two other IOCTL families, NVDIMM_FAMILY_{HPE,MSFT}.

 - Enhance nfit_test so we can test some of the new things added in
   version 1.6 of the DSM specification. This includes testing firmware
   download and simulating the Last Shutdown State (LSS) status.

* tag 'libnvdimm-for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (37 commits)
  libnvdimm, namespace: remove redundant initialization of 'nd_mapping'
  acpi, nfit: fix register dimm error handling
  libnvdimm, namespace: make min namespace size 4K
  tools/testing/nvdimm: force nfit_test to depend on instrumented modules
  libnvdimm/nfit_test: adding support for unit testing enable LSS status
  libnvdimm/nfit_test: add firmware download emulation
  nfit-test: Add platform cap support from ACPI 6.2a to test
  libnvdimm: expose platform persistence attribute for nd_region
  acpi: nfit: add persistent memory control flag for nd_region
  acpi: nfit: Add support for detect platform CPU cache flush on power loss
  device-dax: Fix trailing semicolon
  libnvdimm, btt: fix uninitialized err_lock
  dax: require 'struct page' by default for filesystem dax
  ext2: auto disable dax instead of failing mount
  ext4: auto disable dax instead of failing mount
  mm, dax: introduce pfn_t_special()
  mm: Fix devm_memremap_pages() collision handling
  mm: Fix memory size alignment in devm_memremap_pages_release()
  memremap: merge find_dev_pagemap into get_dev_pagemap
  memremap: change devm_memremap_pages interface to use struct dev_pagemap
  ...
2018-02-06 10:41:33 -08:00
William Kucharski
da391d640c mm: correct comments regarding do_fault_around()
There are multiple comments surrounding do_fault_around that memtion
fault_around_pages() and fault_around_mask(), two routines that do not
exist.  These comments should be reworded to reference
fault_around_bytes, the value which is used to determine how much
do_fault_around() will attempt to read when processing a fault.

These comments should have been updated when fault_around_pages() and
fault_around_mask() were removed in commit aecd6f4426 ("mm: close race
between do_fault_around() and fault_around_bytes_set()").

Fixes: aecd6f4426 ("mm: close race between do_fault_around() and fault_around_bytes_set()")
Link: http://lkml.kernel.org/r/302D0B14-C7E9-44C6-8BED-033F9ACBD030@oracle.com
Signed-off-by: William Kucharski <william.kucharski@oracle.com>
Reviewed-by: Larry Bassel <larry.bassel@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
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>
2018-01-31 17:18:40 -08:00
Matthew Wilcox
977fbdcd59 mm: add unmap_mapping_pages()
Several users of unmap_mapping_range() would prefer to express their
range in pages rather than bytes.  Unfortuately, on a 32-bit kernel, you
have to remember to cast your page number to a 64-bit type before
shifting it, and four places in the current tree didn't remember to do
that.  That's a sign of a bad interface.

Conveniently, unmap_mapping_range() actually converts from bytes into
pages, so hoist the guts of unmap_mapping_range() into a new function
unmap_mapping_pages() and convert the callers which want to use pages.

Link: http://lkml.kernel.org/r/20171206142627.GD32044@bombadil.infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Reported-by: "zhangyi (F)" <yi.zhang@huawei.com>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Acked-by: 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>
2018-01-31 17:18:37 -08:00
Mike Rapoport
ef549e13cf mm: update comment describing tlb_gather_mmu
The comment describes @fullmm argument, but the function has no such
parameter.

Update the comment to match the code and convert it to kernel-doc
markup.

Link: http://lkml.kernel.org/r/1512394531-2264-1-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-01-31 17:18:37 -08:00
Dan Williams
785a3fab4a mm, dax: introduce pfn_t_special()
In support of removing the VM_MIXEDMAP indication from DAX VMAs,
introduce pfn_t_special() for drivers to indicate that _PAGE_SPECIAL
should be used for DAX ptes. This also helps identify drivers like
dccssblk that only want to use DAX in a read-only fashion without
get_user_pages() support.

Ideally we could delete axonram and dcssblk DAX support, but if we need
to keep it better make it explicit that axonram and dcssblk only support
a sub-set of DAX due to missing _PAGE_DEVMAP support.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-01-19 16:50:53 -08:00
Minchan Kim
f80207727a mm/memory.c: release locked page in do_swap_page()
James reported a bug in swap paging-in from his testing.  It is that
do_swap_page doesn't release locked page so system hang-up happens due
to a deadlock on PG_locked.

It was introduced by 0bcac06f27 ("mm, swap: skip swapcache for swapin
of synchronous device") because I missed swap cache hit places to update
swapcache variable to work well with other logics against swapcache in
do_swap_page.

This patch fixes it.

Debugged by James Bottomley.

Link: http://lkml.kernel.org/r/<1514407817.4169.4.camel@HansenPartnership.com>
Link: http://lkml.kernel.org/r/20180102235606.GA19438@bbox
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reported-by: James Bottomley <James.Bottomley@hansenpartnership.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-01-19 10:09:40 -08:00
Linus Torvalds
f6f3732162 Revert "mm: replace p??_write with pte_access_permitted in fault + gup paths"
This reverts commits 5c9d2d5c26, c7da82b894, and e7fe7b5cae.

We'll probably need to revisit this, but basically we should not
complicate the get_user_pages_fast() case, and checking the actual page
table protection key bits will require more care anyway, since the
protection keys depend on the exact state of the VM in question.

Particularly when doing a "remote" page lookup (ie in somebody elses VM,
not your own), you need to be much more careful than this was.  Dave
Hansen says:

 "So, the underlying bug here is that we now a get_user_pages_remote()
  and then go ahead and do the p*_access_permitted() checks against the
  current PKRU. This was introduced recently with the addition of the
  new p??_access_permitted() calls.

  We have checks in the VMA path for the "remote" gups and we avoid
  consulting PKRU for them. This got missed in the pkeys selftests
  because I did a ptrace read, but not a *write*. I also didn't
  explicitly test it against something where a COW needed to be done"

It's also not entirely clear that it makes sense to check the protection
key bits at this level at all.  But one possible eventual solution is to
make the get_user_pages_fast() case just abort if it sees protection key
bits set, which makes us fall back to the regular get_user_pages() case,
which then has a vma and can do the check there if we want to.

We'll see.

Somewhat related to this all: what we _do_ want to do some day is to
check the PAGE_USER bit - it should obviously always be set for user
pages, but it would be a good check to have back.  Because we have no
generic way to test for it, we lost it as part of moving over from the
architecture-specific x86 GUP implementation to the generic one in
commit e585513b76 ("x86/mm/gup: Switch GUP to the generic
get_user_page_fast() implementation").

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-12-15 18:53:22 -08:00
Geert Uytterhoeven
183f24aa5b mm/memory.c: mark wp_huge_pmd() inline to prevent build failure
With gcc 4.1.2:

    mm/memory.o: In function `wp_huge_pmd':
    memory.c:(.text+0x9b4): undefined reference to `do_huge_pmd_wp_page'

Interestingly, wp_huge_pmd() is emitted in the assembler output, but
never called.

Apparently replacing the call to pmd_write() in __handle_mm_fault() by a
call to the more complex pmd_access_permitted() reduced the ability of
the compiler to remove unused code.

Fix this by marking wp_huge_pmd() inline, like was done in commit
91a90140f9 ("mm/memory.c: mark create_huge_pmd() inline to prevent
build failure") for a similar problem.

[akpm@linux-foundation.org: add comment]
Link: http://lkml.kernel.org/r/1512335500-10889-1-git-send-email-geert@linux-m68k.org
Fixes: c7da82b894 ("mm: replace pmd_write with pmd_access_permitted in fault + gup paths")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-12-14 16:00:48 -08:00
Linus Torvalds
a0908a1b7d Merge branch 'akpm' (patches from Andrew)
Mergr misc fixes from Andrew Morton:
 "28 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (28 commits)
  fs/hugetlbfs/inode.c: change put_page/unlock_page order in hugetlbfs_fallocate()
  mm/hugetlb: fix NULL-pointer dereference on 5-level paging machine
  autofs: revert "autofs: fix AT_NO_AUTOMOUNT not being honored"
  autofs: revert "autofs: take more care to not update last_used on path walk"
  fs/fat/inode.c: fix sb_rdonly() change
  mm, memcg: fix mem_cgroup_swapout() for THPs
  mm: migrate: fix an incorrect call of prep_transhuge_page()
  kmemleak: add scheduling point to kmemleak_scan()
  scripts/bloat-o-meter: don't fail with division by 0
  fs/mbcache.c: make count_objects() more robust
  Revert "mm/page-writeback.c: print a warning if the vm dirtiness settings are illogical"
  mm/madvise.c: fix madvise() infinite loop under special circumstances
  exec: avoid RLIMIT_STACK races with prlimit()
  IB/core: disable memory registration of filesystem-dax vmas
  v4l2: disable filesystem-dax mapping support
  mm: fail get_vaddr_frames() for filesystem-dax mappings
  mm: introduce get_user_pages_longterm
  device-dax: implement ->split() to catch invalid munmap attempts
  mm, hugetlbfs: introduce ->split() to vm_operations_struct
  scripts/faddr2line: extend usage on generic arch
  ...
2017-11-29 19:12:44 -08:00
Dan Williams
5c9d2d5c26 mm: replace pte_write with pte_access_permitted in fault + gup paths
The 'access_permitted' helper is used in the gup-fast path and goes
beyond the simple _PAGE_RW check to also:

 - validate that the mapping is writable from a protection keys
   standpoint

 - validate that the pte has _PAGE_USER set since all fault paths where
   pte_write is must be referencing user-memory.

Link: http://lkml.kernel.org/r/151043111604.2842.8051684481794973100.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-29 18:40:42 -08:00
Dan Williams
c7da82b894 mm: replace pmd_write with pmd_access_permitted in fault + gup paths
The 'access_permitted' helper is used in the gup-fast path and goes
beyond the simple _PAGE_RW check to also:

 - validate that the mapping is writable from a protection keys
   standpoint

 - validate that the pte has _PAGE_USER set since all fault paths where
   pmd_write is must be referencing user-memory.

Link: http://lkml.kernel.org/r/151043111049.2842.15241454964150083466.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-29 18:40:42 -08:00
Dan Williams
e7fe7b5cae mm: replace pud_write with pud_access_permitted in fault + gup paths
The 'access_permitted' helper is used in the gup-fast path and goes
beyond the simple _PAGE_RW check to also:

 - validate that the mapping is writable from a protection keys
   standpoint

 - validate that the pte has _PAGE_USER set since all fault paths where
   pud_write is must be referencing user-memory.

[dan.j.williams@intel.com: fix powerpc compile error]
  Link: http://lkml.kernel.org/r/151129127237.37405.16073414520854722485.stgit@dwillia2-desk3.amr.corp.intel.com
Link: http://lkml.kernel.org/r/151043110453.2842.2166049702068628177.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-29 18:40:42 -08:00
Linus Torvalds
f55e1014f9 Revert "mm, thp: Do not make pmd/pud dirty without a reason"
This reverts commit 152e93af3c.

It was a nice cleanup in theory, but as Nicolai Stange points out, we do
need to make the page dirty for the copy-on-write case even when we
didn't end up making it writable, since the dirty bit is what we use to
check that we've gone through a COW cycle.

Reported-by: Michal Hocko <mhocko@kernel.org>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-29 09:01:01 -08:00
Kirill A. Shutemov
152e93af3c mm, thp: Do not make pmd/pud dirty without a reason
Currently we make page table entries dirty all the time regardless of
access type and don't even consider if the mapping is write-protected.
The reasoning is that we don't really need dirty tracking on THP and
making the entry dirty upfront may save some time on first write to the
page.

Unfortunately, such approach may result in false-positive
can_follow_write_pmd() for huge zero page or read-only shmem file.

Let's only make page dirty only if we about to write to the page anyway
(as we do for small pages).

I've restructured the code to make entry dirty inside
maybe_p[mu]d_mkwrite(). It also takes into account if the vma is
write-protected.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-27 12:26:29 -08:00