Commit graph

19716 commits

Author SHA1 Message Date
James Morris
0ffbe2699c Merge branch 'master' into next 2010-05-06 10:56:07 +10:00
Jean Delvare
6629dcff19 i2c-core: Use per-adapter userspace device lists
Using a single list for all userspace devices leads to a dead lock
on multiplexed buses in some circumstances (mux chip instantiated
from userspace). This is solved by using a separate list for each
bus segment.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Michael Lawnick <ml.lawnick@gmx.de>
2010-05-04 11:09:28 +02:00
Daniel Mack
073900a28d USB: rename usb_buffer_alloc() and usb_buffer_free()
For more clearance what the functions actually do,

  usb_buffer_alloc() is renamed to usb_alloc_coherent()
  usb_buffer_free()  is renamed to usb_free_coherent()

They should only be used in code which really needs DMA coherency.

[added compatibility macros so we can convert things easier - gregkh]

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Pedro Ribeiro <pedrib@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-04-30 09:25:12 -07:00
Linus Torvalds
27fb8d7b1f Merge branch 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6
* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
  nfs: fix memory leak in nfs_get_sb with CONFIG_NFS_V4
  nfs: fix some issues in nfs41_proc_reclaim_complete()
  NFS: Ensure that nfs_wb_page() waits for Pg_writeback to clear
  NFS: Fix an unstable write data integrity race
  nfs: testing for null instead of ERR_PTR()
  NFS: rsize and wsize settings ignored on v4 mounts
  NFSv4: Don't attempt an atomic open if the file is a mountpoint
  SUNRPC: Fix a bug in rpcauth_prune_expired
2010-04-29 10:23:44 -07:00
Linus Torvalds
970b06485f Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  coda: move backing-dev.h kernel include inside __KERNEL__
  mtd: ensure that bdi entries are properly initialized and registered
  Move mtd_bdi_*mappable to mtdcore.c
  btrfs: convert to using bdi_setup_and_register()
  Catch filesystems lacking s_bdi
  drbd: Terminate a connection early if sending the protocol fails
  drbd: fix memory leak
  Fix JFFS2 sync silent failure
  smbfs: add bdi backing to mount session
  ncpfs: add bdi backing to mount session
  exofs: add bdi backing to mount session
  ecryptfs: add bdi backing to mount session
  coda: add bdi backing to mount session
  cifs: add bdi backing to mount session
  afs: add bdi backing to mount session.
  9p: add bdi backing to mount session
  bdi: add helper function for doing init and register of a bdi for a file system
  block: ensure jiffies wrap is handled correctly in blk_rq_timed_out_timer
2010-04-28 07:56:05 -07:00
Jens Axboe
33f60e9640 coda: move backing-dev.h kernel include inside __KERNEL__
Otherwise we must export backing-dev.h as well, which doesn't make
any sense.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-04-28 09:20:33 +02:00
Eric Paris
cb84aa9b42 LSM Audit: rename LSM_AUDIT_NO_AUDIT to LSM_AUDIT_DATA_NONE
Most of the LSM common audit work uses LSM_AUDIT_DATA_* for the naming.
This was not so for LSM_AUDIT_NO_AUDIT which means the generic initializer
cannot be used.  This patch just renames the flag so the generic
initializer can be used.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-28 08:51:12 +10:00
Jörn Engel
5129a469a9 Catch filesystems lacking s_bdi
noop_backing_dev_info is used only as a flag to mark filesystems that
don't have any backing store, like tmpfs, procfs, spufs, etc.

Signed-off-by: Joern Engel <joern@logfs.org>

Changed the BUG_ON() to a WARN_ON(). Note that adding dirty inodes
to the noop_backing_dev_info is not legal and will not result in
them being flushed, but we already catch this condition in
__mark_inode_dirty() when checking for a registered bdi.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-04-25 08:54:42 +02:00
Mel Gorman
23be7468e8 hugetlb: fix infinite loop in get_futex_key() when backed by huge pages
If a futex key happens to be located within a huge page mapped
MAP_PRIVATE, get_futex_key() can go into an infinite loop waiting for a
page->mapping that will never exist.

See https://bugzilla.redhat.com/show_bug.cgi?id=552257 for more details
about the problem.

This patch makes page->mapping a poisoned value that includes
PAGE_MAPPING_ANON mapped MAP_PRIVATE.  This is enough for futex to
continue but because of PAGE_MAPPING_ANON, the poisoned value is not
dereferenced or used by futex.  No other part of the VM should be
dereferencing the page->mapping of a hugetlbfs page as its page cache is
not on the LRU.

This patch fixes the problem with the test case described in the bugzilla.

[akpm@linux-foundation.org: mel cant spel]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Darren Hart <darren@dvhart.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-04-24 11:31:25 -07:00
Josef Bacik
3a3076f4d6 Cleanup generic block based fiemap
This cleans up a few of the complaints of __generic_block_fiemap.  I've
fixed all the typing stuff, used inline functions instead of macros,
gotten rid of a couple of variables, and made sure the size and block
requests are all block aligned.  It also fixes a problem where sometimes
FIEMAP_EXTENT_LAST wasn't being set properly.

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-04-23 10:39:48 -07:00
Linus Torvalds
cfc94b2c9a Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
  firewire: ohci: wait for local CSR lock access to finish
  firewire: ohci: prevent aliasing of locally handled register addresses
  firewire: core: fw_iso_resource_manage: return -EBUSY when out of resources
  firewire: core: fix retries calculation in iso manage_channel()
  firewire: cdev: fix cut+paste mistake in disclaimer
2010-04-22 12:54:54 -07:00
Trond Myklebust
71d0a6112a NFS: Fix an unstable write data integrity race
Commit 2c61be0a94 (NFS: Ensure that the WRITE
and COMMIT RPC calls are always uninterruptible) exposed a race on file
close. In order to ensure correct close-to-open behaviour, we want to wait
for all outstanding background commit operations to complete.

This patch adds an inode flag that indicates if a commit operation is under
way, and provides a mechanism to allow ->write_inode() to wait for its
completion if this is a data integrity flush.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-04-22 15:35:57 -04:00
Jens Axboe
424264b7b2 smbfs: add bdi backing to mount session
This ensures that dirty data gets flushed properly.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-04-22 12:37:07 +02:00
Jens Axboe
f1970c73cb ncpfs: add bdi backing to mount session
This ensures that dirty data gets flushed properly.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-04-22 12:31:11 +02:00
Jens Axboe
5163d90076 coda: add bdi backing to mount session
This ensures that dirty data gets flushed properly.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-04-22 12:12:40 +02:00
Jens Axboe
c3c532061e bdi: add helper function for doing init and register of a bdi for a file system
Pretty trivial helper, just sets up the bdi and registers it. An atomic
sequence count is used to ensure that the registered sysfs names are
unique.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-04-22 11:39:36 +02:00
Linus Torvalds
458f8c895b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lrg/voltage-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lrg/voltage-2.6:
  mc13783-regulator: fix a memory leak in mc13783_regulator_remove
  regulator: Let drivers know when they use the stub API
2010-04-21 12:31:52 -07:00
Sridhar Samudrala
e80e2a60ff KVM: Increase NR_IOBUS_DEVS limit to 200
This patch increases the current hardcoded limit of NR_IOBUS_DEVS
from 6 to 200. We are hitting this limit when creating a guest with more
than 1 virtio-net device using vhost-net backend. Each virtio-net
device requires 2 such devices to service notifications from rx/tx queues.

Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-04-20 13:08:30 +03:00
Takuya Yoshikawa
87bf6e7de1 KVM: fix the handling of dirty bitmaps to avoid overflows
Int is not long enough to store the size of a dirty bitmap.

This patch fixes this problem with the introduction of a wrapper
function to calculate the sizes of dirty bitmaps.

Note: in mark_page_dirty(), we have to consider the fact that
  __set_bit() takes the offset as int, not long.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2010-04-20 13:06:55 +03:00
Linus Torvalds
85341c6136 Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  rcu: Make RCU lockdep check the lockdep_recursion variable
  rcu: Update docs for rcu_access_pointer and rcu_dereference_protected
  rcu: Better explain the condition parameter of rcu_dereference_check()
  rcu: Add rcu_access_pointer and rcu_dereference_protected
2010-04-19 08:35:47 -07:00
Jean Delvare
be1a50d4eb regulator: Let drivers know when they use the stub API
Have the stub variant of regulator_get() return NULL, so that drivers
can (but still don't have to) handle this case specifically.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Jerome Oufella <jerome.oufella@savoirfairelinux.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-04-19 13:17:10 +01:00
Paul E. McKenney
bc293d62b2 rcu: Make RCU lockdep check the lockdep_recursion variable
The lockdep facility temporarily disables lockdep checking by
incrementing the current->lockdep_recursion variable.  Such
disabling happens in NMIs and in other situations where lockdep
might expect to recurse on itself.

This patch therefore checks current->lockdep_recursion, disabling RCU
lockdep splats when this variable is non-zero.  In addition, this patch
removes the "likely()", as suggested by Lai Jiangshan.

Reported-by: Frederic Weisbecker <fweisbec@gmail.com>
Reported-by: David Miller <davem@davemloft.net>
Tested-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
Cc: eric.dumazet@gmail.com
LKML-Reference: <20100415195039.GA22623@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-19 08:37:19 +02:00
Stefan Richter
a2612cb16d firewire: cdev: fix cut+paste mistake in disclaimer
This was supposed to be generic "authors or copyright holders";
I mistakenly picked up text from a wrong file.

Reported-by: Daniel K. <dk@uw.no>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-04-15 22:18:36 +02:00
Linus Torvalds
2fed94c032 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
  firewire: cdev: change license of exported header files to MIT license
  firewire: cdev: comment fixlet
  firewire: cdev: iso packet documentation
  firewire: cdev: fix information leak
  firewire: cdev: require quadlet-aligned headers for transmit packets
  firewire: cdev: disallow receive packets without header
2010-04-15 11:56:20 -07:00
Linus Torvalds
00eef7bd01 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: wacom - switch mode upon system resume
  Revert "Input: wacom - merge out and in prox events"
  Input: matrix_keypad - allow platform to disable key autorepeat
  Input: ALPS - add signature for HP Pavilion dm3 laptops
  Input: i8042 - spelling fix
  Input: sparse-keymap - implement safer freeing of the keymap
  Input: update the status of the Multitouch X driver project
  Input: clarify the no-finger event in multitouch protocol
  Input: bcm5974 - retract efi-broken suspend_resume
  Input: sparse-keymap - free the right keymap on error
2010-04-15 11:49:55 -07:00
Stefan Richter
19b3eecc21 firewire: cdev: change license of exported header files to MIT license
Among else, this allows projects like libdc1394 to carry copies of the
ABI related header files without them or distributors having to worry
about effects on the project's overall license terms.  Switch to MIT
license as suggested by Kristian.  Also update the year in the
copyright statement according to source history.

Cc: Jay Fenlason <fenlason@redhat.com>
Acked-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Kristian Høgsberg <krh@bitplanet.net>
2010-04-15 17:50:49 +02:00
David Howells
c08c68dd76 rcu: Better explain the condition parameter of rcu_dereference_check()
Better explain the condition parameter of
rcu_dereference_check() that describes the conditions under
which the dereference is permitted to take place (and
incorporate Yong Zhang's suggestion).  This condition is only
checked under lockdep proving.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: eric.dumazet@gmail.com
LKML-Reference: <1270852752-25278-2-git-send-email-paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-14 12:20:04 +02:00
Paul E. McKenney
b62730baea rcu: Add rcu_access_pointer and rcu_dereference_protected
This patch adds variants of rcu_dereference() that handle
situations where the RCU-protected data structure cannot change,
perhaps due to our holding the update-side lock, or where the
RCU-protected pointer is only to be fetched, not dereferenced.
These are needed due to some performance concerns with using
rcu_dereference() where it is not required, aside from the need
for lockdep/sparse checking.

The new rcu_access_pointer() primitive is for the case where the
pointer is be fetch and not dereferenced.  This primitive may be
used without protection, RCU or otherwise, due to the fact that
it uses ACCESS_ONCE().

The new rcu_dereference_protected() primitive is for the case
where updates are prevented, for example, due to holding the
update-side lock.  This primitive does neither ACCESS_ONCE() nor
smp_read_barrier_depends(), so can only be used when updates are
somehow prevented.

Suggested-by: David Howells <dhowells@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
Cc: eric.dumazet@gmail.com
LKML-Reference: <1270852752-25278-1-git-send-email-paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-14 12:19:51 +02:00
Trond Myklebust
0df5dd4aae NFSv4: fix delegated locking
Arnaud Giersch reports that NFSv4 locking is broken when we hold a
delegation since commit 8e469ebd6d (NFSv4:
Don't allow posix locking against servers that don't support it).

According to Arnaud, the lock succeeds the first time he opens the file
(since we cannot do a delegated open) but then fails after we start using
delegated opens.

The following patch fixes it by ensuring that locking behaviour is
governed by a per-filesystem capability flag that is initially set, but
gets cleared if the server ever returns an OPEN without the
NFS4_OPEN_RESULT_LOCKTYPE_POSIX flag being set.

Reported-by: Arnaud Giersch <arnaud.giersch@iut-bm.univ-fcomte.fr>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
2010-04-12 07:55:15 -04:00
Eric Paris
05b90496f2 security: remove dead hook acct
Unused hook.  Remove.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12 12:19:19 +10:00
Eric Paris
3011a344cd security: remove dead hook key_session_to_parent
Unused hook.  Remove.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12 12:19:18 +10:00
Eric Paris
6307f8fee2 security: remove dead hook task_setgroups
Unused hook.  Remove.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12 12:19:18 +10:00
Eric Paris
06ad187e28 security: remove dead hook task_setgid
Unused hook.  Remove.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12 12:19:17 +10:00
Eric Paris
43ed8c3b45 security: remove dead hook task_setuid
Unused hook.  Remove.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12 12:19:16 +10:00
Eric Paris
0968d0060a security: remove dead hook cred_commit
Unused hook.  Remove.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12 12:19:15 +10:00
Eric Paris
9d5ed77dad security: remove dead hook inode_delete
Unused hook.  Remove.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12 12:19:15 +10:00
Eric Paris
91a9420f58 security: remove dead hook sb_post_pivotroot
Unused hook.  Remove.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12 12:18:32 +10:00
Eric Paris
3db2910177 security: remove dead hook sb_post_addmount
Unused hook.  Remove.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12 12:18:31 +10:00
Eric Paris
82dab10453 security: remove dead hook sb_post_remount
Unused hook.  Remove.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12 12:18:30 +10:00
Eric Paris
4b61d12c84 security: remove dead hook sb_umount_busy
Unused hook.  Remove.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12 12:18:30 +10:00
Eric Paris
231923bd0e security: remove dead hook sb_umount_close
Unused hook.  Remove.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12 12:18:29 +10:00
Eric Paris
353633100d security: remove sb_check_sb hooks
Unused hook.  Remove it.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12 12:18:28 +10:00
Stefan Richter
ca658b1e29 firewire: cdev: comment fixlet
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-04-10 16:51:13 +02:00
Clemens Ladisch
aa6fec3cde firewire: cdev: iso packet documentation
Add the missing documentation for iso packets.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-04-10 16:51:13 +02:00
Linus Torvalds
2f4084209a Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block: (34 commits)
  cfq-iosched: Fix the incorrect timeslice accounting with forced_dispatch
  loop: Update mtime when writing using aops
  block: expose the statistics in blkio.time and blkio.sectors for the root cgroup
  backing-dev: Handle class_create() failure
  Block: Fix block/elevator.c elevator_get() off-by-one error
  drbd: lc_element_by_index() never returns NULL
  cciss: unlock on error path
  cfq-iosched: Do not merge queues of BE and IDLE classes
  cfq-iosched: Add additional blktrace log messages in CFQ for easier debugging
  i2o: Remove the dangerous kobj_to_i2o_device macro
  block: remove 16 bytes of padding from struct request on 64bits
  cfq-iosched: fix a kbuild regression
  block: make CONFIG_BLK_CGROUP visible
  Remove GENHD_FL_DRIVERFS
  block: Export max number of segments and max segment size in sysfs
  block: Finalize conversion of block limits functions
  block: Fix overrun in lcm() and move it to lib
  vfs: improve writeback_inodes_wb()
  paride: fix off-by-one test
  drbd: fix al-to-on-disk-bitmap for 4k logical_block_size
  ...
2010-04-09 11:50:29 -07:00
David Howells
ce82653d6c radix_tree_tag_get() is not as safe as the docs make out [ver #2]
radix_tree_tag_get() is not safe to use concurrently with radix_tree_tag_set()
or radix_tree_tag_clear().  The problem is that the double tag_get() in
radix_tree_tag_get():

		if (!tag_get(node, tag, offset))
			saw_unset_tag = 1;
		if (height == 1) {
			int ret = tag_get(node, tag, offset);

may see the value change due to the action of set/clear.  RCU is no protection
against this as no pointers are being changed, no nodes are being replaced
according to a COW protocol - set/clear alter the node directly.

The documentation in linux/radix-tree.h, however, says that
radix_tree_tag_get() is an exception to the rule that "any function modifying
the tree or tags (...) must exclude other modifications, and exclude any
functions reading the tree".

The problem is that the next statement in radix_tree_tag_get() checks that the
tag doesn't vary over time:

			BUG_ON(ret && saw_unset_tag);

This has been seen happening in FS-Cache:

	https://www.redhat.com/archives/linux-cachefs/2010-April/msg00013.html

To this end, remove the BUG_ON() from radix_tree_tag_get() and note in various
comments that the value of the tag may change whilst the RCU read lock is held,
and thus that the return value of radix_tree_tag_get() may not be relied upon
unless radix_tree_tag_set/clear() and radix_tree_delete() are excluded from
running concurrently with it.

Reported-by: Romain DEGEZ <romain.degez@smartjog.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-04-09 10:12:03 -07:00
Pekka Enberg
fc1c183353 slab: Generify kernel pointer validation
As suggested by Linus, introduce a kern_ptr_validate() helper that does some
sanity checks to make sure a pointer is a valid kernel pointer.  This is a
preparational step for fixing SLUB kmem_ptr_validate().

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Nick Piggin <npiggin@suse.de>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-04-09 10:09:50 -07:00
Mark Lord
45c4d015a9 libata: Fix accesses at LBA28 boundary (old bug, but nasty) (v2)
Most drives from Seagate, Hitachi, and possibly other brands,
do not allow LBA28 access to sector number 0x0fffffff (2^28 - 1).
So instead use LBA48 for such accesses.

This bug could bite a lot of systems, especially when the user has
taken care to align partitions to 4KB boundaries. On misaligned systems,
it is less likely to be encountered, since a 4KB read would end at
0x10000000 rather than at 0x0fffffff.

Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2010-04-08 12:53:57 -04:00
Linus Torvalds
cf90bfe2eb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/ide-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/ide-2.6:
  ide: Fix IDE taskfile with cfq scheduler
  ide: Must hold queue lock when requeueing
  ide: Requeue request after DMA timeout
2010-04-08 07:45:36 -07:00
Michael S. Tsirkin
b7a413015d virtio: disable multiport console support.
Move MULTIPORT feature and related config changes
out of exported headers, and disable the feature
at runtime.

At this point, it seems less risky to keep code around
until we can enable it than rip it out completely.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2010-04-08 09:46:19 +09:30