linux-stable.git/include/linux/pagemap.h, branch v3.18.76

fix fault_in_multipages_...() on architectures with no-op access_ok()

2016-10-06T02:40:20+00:00

[ Upstream commit e23d4159b109167126e5bcd7f3775c95de7fee47 ]

Switching iov_iter fault-in to multipages variants has exposed an old
bug in underlying fault_in_multipages_...(); they break if the range
passed to them wraps around.  Normally access_ok() done by callers will
prevent such (and it's a guaranteed EFAULT - ERR_PTR() values fall into
such a range and they should not point to any valid objects).

However, on architectures where userland and kernel live in different
MMU contexts (e.g. s390) access_ok() is a no-op and on those a range
with a wraparound can reach fault_in_multipages_...().

Since any wraparound means EFAULT there, the fix is trivial - turn
those

    while (uaddr <= end)
	    ...
into

    if (unlikely(uaddr > end))
	    return -EFAULT;
    do
	    ...
    while (uaddr <= end);

Reported-by: Jan Stancek 
Tested-by: Jan Stancek 
Cc: stable@vger.kernel.org # v3.5+
Signed-off-by: Al Viro 
Signed-off-by: Linus Torvalds 
Signed-off-by: Sasha Levin

mm: get rid of radix tree gfp mask for pagecache_get_page

2015-01-30T01:40:46+00:00

commit 45f87de57f8fad59302fd263dd81ffa4843b5b24 upstream.

Commit 2457aec63745 ("mm: non-atomically mark page accessed during page
cache allocation where possible") has added a separate parameter for
specifying gfp mask for radix tree allocations.

Not only this is less than optimal from the API point of view because it
is error prone, it is also buggy currently because
grab_cache_page_write_begin is using GFP_KERNEL for radix tree and if
fgp_flags doesn't contain FGP_NOFS (mostly controlled by fs by
AOP_FLAG_NOFS flag) but the mapping_gfp_mask has __GFP_FS cleared then
the radix tree allocation wouldn't obey the restriction and might
recurse into filesystem and cause deadlocks.  This is the case for most
filesystems unfortunately because only ext4 and gfs2 are using
AOP_FLAG_NOFS.

Let's simply remove radix_gfp_mask parameter because the allocation
context is same for both page cache and for the radix tree.  Just make
sure that the radix tree gets only the sane subset of the mask (e.g.  do
not pass __GFP_WRITE).

Long term it is more preferable to convert remaining users of
AOP_FLAG_NOFS to use mapping_gfp_mask instead and simplify this
interface even further.

Reported-by: Dave Chinner 
Signed-off-by: Michal Hocko 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

mm/balloon_compaction: remove balloon mapping and flag AS_BALLOON_MAP

2014-10-10T02:26:01+00:00

Now ballooned pages are detected using PageBalloon().  Fake mapping is no
longer required.  This patch links ballooned pages to balloon device using
field page->private instead of page->mapping.  Also this patch embeds
balloon_dev_info directly into struct virtio_balloon.

Signed-off-by: Konstantin Khlebnikov 
Cc: Rafael Aquini 
Cc: Andrey Ryabinin 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge tag 'nfs-for-3.18-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

2014-10-08T16:49:23+00:00

Pull NFS client updates from Trond Myklebust:
 "Highlights include:

  Stable fixes:
   - fix an NFSv4.1 state renewal regression
   - fix open/lock state recovery error handling
   - fix lock recovery when CREATE_SESSION/SETCLIENTID_CONFIRM fails
   - fix statd when reconnection fails
   - don't wake tasks during connection abort
   - don't start reboot recovery if lease check fails
   - fix duplicate proc entries

  Features:
  - pNFS block driver fixes and clean ups from Christoph
  - More code cleanups from Anna
  - Improve mmap() writeback performance
  - Replace use of PF_TRANS with a more generic mechanism for avoiding
    deadlocks in nfs_release_page"

* tag 'nfs-for-3.18-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (66 commits)
  NFSv4.1: Fix an NFSv4.1 state renewal regression
  NFSv4: fix open/lock state recovery error handling
  NFSv4: Fix lock recovery when CREATE_SESSION/SETCLIENTID_CONFIRM fails
  NFS: Fabricate fscache server index key correctly
  SUNRPC: Add missing support for RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT
  NFSv3: Fix missing includes of nfs3_fs.h
  NFS/SUNRPC: Remove other deadlock-avoidance mechanisms in nfs_release_page()
  NFS: avoid waiting at all in nfs_release_page when congested.
  NFS: avoid deadlocks with loop-back mounted NFS filesystems.
  MM: export page_wakeup functions
  SCHED: add some "wait..on_bit...timeout()" interfaces.
  NFS: don't use STABLE writes during writeback.
  NFSv4: use exponential retry on NFS4ERR_DELAY for async requests.
  rpc: Add -EPERM processing for xs_udp_send_request()
  rpc: return sent and err from xs_sendpages()
  lockd: Try to reconnect if statd has moved
  SUNRPC: Don't wake tasks during connection abort
  Fixing lease renewal
  nfs: fix duplicate proc entries
  pnfs/blocklayout: Fix a 64-bit division/remainder issue in bl_map_stripe
  ...

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial

2014-10-08T01:16:26+00:00

Pull "trivial tree" updates from Jiri Kosina:
 "Usual pile from trivial tree everyone is so eagerly waiting for"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (39 commits)
  Remove MN10300_PROC_MN2WS0038
  mei: fix comments
  treewide: Fix typos in Kconfig
  kprobes: update jprobe_example.c for do_fork() change
  Documentation: change "&" to "and" in Documentation/applying-patches.txt
  Documentation: remove obsolete pcmcia-cs from Changes
  Documentation: update links in Changes
  Documentation: Docbook: Fix generated DocBook/kernel-api.xml
  score: Remove GENERIC_HAS_IOMAP
  gpio: fix 'CONFIG_GPIO_IRQCHIP' comments
  tty: doc: Fix grammar in serial/tty
  dma-debug: modify check_for_stack output
  treewide: fix errors in printk
  genirq: fix reference in devm_request_threaded_irq comment
  treewide: fix synchronize_rcu() in comments
  checkstack.pl: port to AArch64
  doc: queue-sysfs: minor fixes
  init/do_mounts: better syntax description
  MIPS: fix comment spelling
  powerpc/simpleboot: fix comment
  ...

MM: export page_wakeup functions

2014-09-25T12:25:09+00:00

This will allow NFS to wait for PG_private to be cleared and,
particularly, to send a wake-up when it is.

Signed-off-by: NeilBrown 
Acked-by: Andrew Morton 
Signed-off-by: Trond Myklebust

SCHED: add some "wait..on_bit...timeout()" interfaces.

2014-09-25T12:23:57+00:00

In commit c1221321b7c25b53204447cff9949a6d5a7ddddc
   sched: Allow wait_on_bit_action() functions to support a timeout

I suggested that a "wait_on_bit_timeout()" interface would not meet my
need.  This isn't true - I was just over-engineering.

Including a 'private' field in wait_bit_key instead of a focused
"timeout" field was just premature generalization.  If some other
use is ever found, it can be generalized or added later.

So this patch renames "private" to "timeout" with a meaning "stop
waiting when "jiffies" reaches or passes "timeout",
and adds two of the many possible wait..bit..timeout() interfaces:

wait_on_page_bit_killable_timeout(), which is the one I want to use,
and out_of_line_wait_on_bit_timeout() which is a reasonably general
example.  Others can be added as needed.

Acked-by: Peter Zijlstra (Intel) 
Signed-off-by: NeilBrown 
Acked-by: Ingo Molnar 
Signed-off-by: Trond Myklebust

linux/pagemap.h: Fixed a typo in a code comment.

2014-08-26T07:35:54+00:00

Corrected a minor typo in a code comment where 'be' was missing.

Signed-off-by: Raymond L. Rivera 
Signed-off-by: Jiri Kosina

mm: describe mmap_sem rules for __lock_page_or_retry() and callers

2014-08-07T01:01:20+00:00

Add a comment describing the circumstances in which
__lock_page_or_retry() will or will not release the mmap_sem when
returning 0.

Add comments to lock_page_or_retry()'s callers (filemap_fault(),
do_swap_page()) noting the impact on VM_FAULT_RETRY returns.

Add comments on up the call tree, particularly replacing the false "We
return with mmap_sem still held" comments.

Signed-off-by: Paul Cassella 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/rmap.c: fix pgoff calculation to handle hugepage correctly

2014-07-23T22:10:54+00:00

I triggered VM_BUG_ON() in vma_address() when I tried to migrate an
anonymous hugepage with mbind() in the kernel v3.16-rc3.  This is
because pgoff's calculation in rmap_walk_anon() fails to consider
compound_order() only to have an incorrect value.

This patch introduces page_to_pgoff(), which gets the page's offset in
PAGE_CACHE_SIZE.

Kirill pointed out that page cache tree should natively handle
hugepages, and in order to make hugetlbfs fit it, page->index of
hugetlbfs page should be in PAGE_CACHE_SIZE.  This is beyond this patch,
but page_to_pgoff() contains the point to be fixed in a single function.

Signed-off-by: Naoya Horiguchi 
Acked-by: Kirill A. Shutemov 
Cc: Joonsoo Kim 
Cc: Hugh Dickins 
Cc: Rik van Riel 
Cc: Hillf Danton 
Cc: Naoya Horiguchi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds