Tejun Heo [Fri, 6 Dec 2013 20:11:57 +0000 (15:11 -0500)]
cgroup: remove for_each_root_subsys()
After the previous patch which introduced for_each_css(),
for_each_root_subsys() only has two users left. This patch replaces
it with for_each_subsys() + explicit subsys_mask testing and remove
for_each_root_subsys() along with cgroupfs_root->subsys_list handling.
This patch doesn't introduce any behavior changes.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
Tejun Heo [Fri, 6 Dec 2013 20:11:56 +0000 (15:11 -0500)]
cgroup: implement for_each_css()
There are enough places where css's of a cgroup are iterated, which
currently uses for_each_root_subsys() + explicit cgroup_css(). This
patch implements for_each_css() and replaces the above combination
with it.
This patch doesn't introduce any behavior changes.
v2: Updated to apply cleanly on top of v2 of "cgroup: fix css leaks on
online_css() failure"
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
Tejun Heo [Fri, 6 Dec 2013 20:11:56 +0000 (15:11 -0500)]
cgroup: factor out cgroup_subsys_state creation into create_css()
Now that all opertations to create a css (cgroup_subsys_state) are
collected into a single loop in cgroup_create(), it's easy to factor
it out into its own function. Factor out css creation into
create_css(). This makes the code easier to follow and will enable
decoupling css creation from cgroup creation which is necessary for
the planned unified hierarchy.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
Tejun Heo [Fri, 6 Dec 2013 20:11:56 +0000 (15:11 -0500)]
cgroup: combine css handling loops in cgroup_create()
Now that css operations in cgroup_create() are back-to-back, there
isn't much point in allocating css's in one loop and onlining them in
another. Merge the two loops so that a css is allocated and onlined
on each iteration.
css_ar[] is no longer necessary and replaced with a single pointer.
This also simplifies the error handling path.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
Tejun Heo [Fri, 6 Dec 2013 20:11:56 +0000 (15:11 -0500)]
cgroup: reorder operations in cgroup_create()
cgroup_create() currently does the followings.
1. alloc cgroup
2. alloc css's
3. create the directory and commit to cgroup creation
4. online css's
5. create cgroup and css files
The sequence performs allocations before other operations but it
doesn't buy anything because each of the above steps may fail and
should be unrollable. Reorganize the sequence such that cgroup
operations are done before css operations.
1. alloc cgroup
2. create the directory and files and commit to cgroup creation
3. alloc css's
4. create files for and online css's
This simplifies the code a bit and enables further simplification and
separating out css creation from cgroup creation which is necessary
for the planned unified hierarchy where css's will be created and
destroyed dynamically across the lifetime of a cgroup.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
Tejun Heo [Fri, 6 Dec 2013 20:11:56 +0000 (15:11 -0500)]
cgroup: make for_each_subsys() useable under cgroup_root_mutex
We want to use for_each_subsys() in cgroupfs_root handling where only
cgroup_root_mutex is held. The only way cgroup_subsys[] can change is
through module load/unload, make cgroup_[un]load_subsys() grab
cgroup_root_mutex too and update the lockdep annotation in
for_each_subsys() to allow either cgroup_mutex or cgroup_root_mutex.
* Lockdep annotation is moved from inner 'if' condition to outer 'for'
init caluse. There's no reason to execute the assertion every loop.
* Loop index @i is renamed to @ssid. Indices iterating through subsys
will be [re]named to @ssid gradually.
v2: cgroup_assert_mutex_or_root_locked() caused build failure if
!CONFIG_LOCKEDP. Conditionalize its definition. The build failure
was reported by kbuild test bot.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Cc: kbuild test robot <fengguang.wu@intel.com>
Tejun Heo [Fri, 6 Dec 2013 20:11:55 +0000 (15:11 -0500)]
cgroup: css iterations and css_from_dir() are safe under cgroup_mutex
Currently, all css iterations and css_from_dir() require RCU read lock
whether the caller is holding cgroup_mutex or not, which is
unnecessarily restrictive. They are all safe to use under
cgroup_mutex without holding RCU read lock.
Factor out cgroup_assert_mutex_or_rcu_locked() from css_from_id() and
apply it to all css iteration functions and css_from_dir().
v2: cgroup_assert_mutex_or_rcu_locked() definition doesn't need to be
inside CONFIG_PROVE_RCU ifdef as rcu_lockdep_assert() is always
defined and conditionalized. Move it outside of the ifdef block.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
Tejun Heo [Fri, 6 Dec 2013 20:07:32 +0000 (15:07 -0500)]
cgroup: fix cgroup_create() error handling path
ae7f164a09 ("cgroup: move cgroup->subsys[] assignment to
online_css()") moved cgroup->subsys[] assignements later in
cgroup_create() but didn't update error handling path accordingly
leading to the following oops and leaking later css's after an
online_css() failure. The oops is from cgroup destruction path being
invoked on the partially constructed cgroup which is not ready to
handle empty slots in cgrp->subsys[] array.
This patch moves reference bumping inside online_css() loop, clears
css_ar[] as css's are brought online successfully, and updates
err_destroy path so that either a css is fully online and destroyed by
cgroup_destroy_locked() or the error path frees it. This creates a
duplicate css free logic in the error path but it will be cleaned up
soon.
v2: Li pointed out that cgroup_destroy_locked() would do NULL-deref if
invoked with a cgroup which doesn't have all css's populated.
Update cgroup_destroy_locked() so that it skips NULL css's.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Reported-by: Vladimir Davydov <vdavydov@parallels.com> Cc: stable@vger.kernel.org # v3.12+
Tejun Heo [Thu, 5 Dec 2013 17:28:04 +0000 (12:28 -0500)]
cgroup: unify pidlist and other file handling
In preparation of conversion to kernfs, cgroup file handling is
updated so that it can be easily mapped to kernfs. With the previous
changes, the difference between pidlist and other files are very
small. Both are served by seq_file in a pretty standard way with the
only difference being !pidlist files use single_open().
This patch adds cftype->seq_start(), ->seq_next and ->seq_stop() and
implements the matching cgroup_seqfile_start/next/stop() which either
emulates single_open() behavior or invokes cftype->seq_*() operations
if specified. This allows using single seq_operations for both
pidlist and other files and makes cgroup_pidlist_operations and
cgorup_pidlist_open() no longer necessary. As cgroup_pidlist_open()
was the only user of cftype->open(), the method is dropped together.
This brings cftype file interface very close to kernfs interface and
mapping shouldn't be too difficult. Once converted to kernfs, most of
the plumbing code including cgroup_seqfile_*() will be removed as
kernfs provides those facilities.
This patch does not introduce any behavior changes.
v2: Refreshed on top of the updated "cgroup: introduce struct
cgroup_pidlist_open_file".
v3: Refreshed on top of the updated "cgroup: attach cgroup_open_file
to all cgroup files".
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
Tejun Heo [Thu, 5 Dec 2013 17:28:04 +0000 (12:28 -0500)]
cgroup: replace cftype->read_seq_string() with cftype->seq_show()
In preparation of conversion to kernfs, cgroup file handling is
updated so that it can be easily mapped to kernfs. This patch
replaces cftype->read_seq_string() with cftype->seq_show() which is
not limited to single_open() operation and will map directcly to
kernfs seq_file interface.
The conversions are mechanical. As ->seq_show() doesn't have @css and
@cft, the functions which make use of them are converted to use
seq_css() and seq_cft() respectively. In several occassions, e.f. if
it has seq_string in its name, the function name is updated to fit the
new method better.
This patch does not introduce any behavior changes.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Aristeu Rozanski <arozansk@redhat.com> Acked-by: Vivek Goyal <vgoyal@redhat.com> Acked-by: Michal Hocko <mhocko@suse.cz> Acked-by: Daniel Wagner <daniel.wagner@bmw-carit.de> Acked-by: Li Zefan <lizefan@huawei.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Balbir Singh <bsingharora@gmail.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Neil Horman <nhorman@tuxdriver.com>
Tejun Heo [Thu, 5 Dec 2013 17:28:04 +0000 (12:28 -0500)]
cgroup: attach cgroup_open_file to all cgroup files
In preparation of conversion to kernfs, cgroup file handling is
updated so that it can be easily mapped to kernfs. This patch
attaches cgroup_open_file, which used to be attached to pidlist files,
to all cgroup files, introduces seq_css/cft() accessors to determine
the cgroup_subsys_state and cftype associated with a given cgroup
seq_file, exports them as public interface.
This doesn't cause any behavior changes but unifies cgroup file
handling across different file types and will help converting them to
kernfs seq_show() interface.
v2: Li pointed out that the original patch was using
single_open_size() incorrectly assuming that the size param is
private data size. Fix it by allocating @of separately and
passing it to single_open() and explicitly freeing it in the
release path. This isn't the prettiest but this path is gonna be
restructured by the following patches pretty soon.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
Tejun Heo [Thu, 5 Dec 2013 17:28:04 +0000 (12:28 -0500)]
cgroup: generalize cgroup_pidlist_open_file
In preparation of conversion to kernfs, cgroup file handling is
updated so that it can be easily mapped to kernfs. This patch renames
cgroup_pidlist_open_file to cgroup_open_file and updates it so that it
only contains a field to identify the specific file, ->cfe, and an
opaque ->priv pointer. When cgroup is converted to kernfs, this will
be replaced by kernfs_open_file which contains about the same
information.
As whether the file is "cgroup.procs" or "tasks" should now be
determined from cgroup_open_file->cfe, the cftype->private for the two
files now carry the file type and cgroup_pidlist_start() reads the
type through cfe->type->private. This makes the distinction between
cgroup_tasks_open() and cgroup_procs_open() unnecessary.
cgroup_pidlist_open() is now directly used as the open method.
This patch doesn't make any behavior changes.
v2: Refreshed on top of the updated "cgroup: introduce struct
cgroup_pidlist_open_file".
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
Tejun Heo [Thu, 5 Dec 2013 17:28:04 +0000 (12:28 -0500)]
cgroup: unify read path so that seq_file is always used
With the recent removal of cftype->read() and ->read_map(), only three
operations are remaining, ->read_u64(), ->read_s64() and
->read_seq_string(). Currently, the first two are handled directly
while the last is handled through seq_file.
It is trivial to serve the first two through the seq_file path too.
This patch restructures read path so that all operations are served
through cgroup_seqfile_show(). This makes all cgroup files seq_file -
single_open/release() are now used by default,
cgroup_seqfile_operations is dropped, and cgroup_file_operations uses
seq_read() for read.
This simplifies the code and makes the read path easy to convert to
use kernfs.
Note that, while cgroup_file_operations uses seq_read() for read, it
still uses generic_file_llseek() for seeking instead of seq_lseek().
This is different from cgroup_seqfile_operations but shouldn't break
anything and brings the seeking behavior aligned with kernfs.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
Tejun Heo [Thu, 5 Dec 2013 17:28:03 +0000 (12:28 -0500)]
cgroup: unify cgroup_write_X64() and cgroup_write_string()
cgroup_write_X64() and cgroup_write_string() both implement about the
same buffering logic. Unify the two into cgroup_file_write() which
always allocates dynamic buffer for simplicity and uses kstrto*()
instead of simple_strto*().
This patch doesn't make any visible behavior changes except for
possibly different error value from kstrsto*().
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
Tejun Heo [Thu, 5 Dec 2013 17:28:03 +0000 (12:28 -0500)]
cgroup: remove cftype->read(), ->read_map() and ->write()
In preparation of conversion to kernfs, cgroup file handling is being
consolidated so that it can be easily mapped to the seq_file based
interface of kernfs.
After recent updates, ->read() and ->read_map() don't have any user
left and ->write() never had any user. Remove them.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
Tejun Heo [Thu, 5 Dec 2013 17:28:03 +0000 (12:28 -0500)]
hugetlb_cgroup: convert away from cftype->read()
In preparation of conversion to kernfs, cgroup file handling is being
consolidated so that it can be easily mapped to the seq_file based
interface of kernfs.
All users of cftype->read() can be easily served, usually better, by
seq_file and other methods. Update hugetlb_cgroup_read() to return
u64 instead of printing itself and rename it to
hugetlb_cgroup_read_u64().
This patch doesn't make any visible behavior changes.
Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Acked-by: Li Zefan <lizefan@huawei.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Johannes Weiner <hannes@cmpxchg.org>
Tejun Heo [Thu, 5 Dec 2013 17:28:02 +0000 (12:28 -0500)]
netprio_cgroup: convert away from cftype->read_map()
In preparation of conversion to kernfs, cgroup file handling is being
consolidated so that it can be easily mapped to the seq_file based
interface of kernfs.
cftype->read_map() doesn't add any value and being replaced with
->read_seq_string(). Update read_priomap() to use ->read_seq_string()
instead.
This patch doesn't make any visible behavior changes.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Daniel Wagner <daniel.wagner@bmw-carit.de> Acked-by: Li Zefan <lizefan@huawei.com>
Tejun Heo [Thu, 5 Dec 2013 17:28:02 +0000 (12:28 -0500)]
memcg: convert away from cftype->read() and ->read_map()
In preparation of conversion to kernfs, cgroup file handling is being
consolidated so that it can be easily mapped to the seq_file based
interface of kernfs.
cftype->read_map() doesn't add any value and being replaced with
->read_seq_string(), and all users of cftype->read() can be easily
served, usually better, by seq_file and other methods.
Update mem_cgroup_read() to return u64 instead of printing itself and
rename it to mem_cgroup_read_u64(), and update
mem_cgroup_oom_control_read() to use ->read_seq_string() instead of
->read_map().
This patch doesn't make any visible behavior changes.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Michal Hocko <mhocko@suse.cz> Acked-by: Li Zefan <lizefan@huawei.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Balbir Singh <bsingharora@gmail.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Tejun Heo [Thu, 5 Dec 2013 17:28:02 +0000 (12:28 -0500)]
cpuset: convert away from cftype->read()
In preparation of conversion to kernfs, cgroup file handling is being
consolidated so that it can be easily mapped to the seq_file based
interface of kernfs.
All users of cftype->read() can be easily served, usually better, by
seq_file and other methods. Rename cpuset_common_file_read() to
cpuset_common_read_seq_string() and convert it to use
read_seq_string() interface instead. This not only simplifies the
code but also makes it more versatile. Before, the file couldn't
output if the result is longer than PAGE_SIZE. After the conversion,
seq_file automatically grows the buffer until the output can fit.
This patch doesn't make any visible behavior changes except for being
able to handle output larger than PAGE_SIZE.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
Tejun Heo [Thu, 5 Dec 2013 17:28:01 +0000 (12:28 -0500)]
cgroup, sched: convert away from cftype->read_map()
In preparation of conversion to kernfs, cgroup file handling is being
consolidated so that it can be easily mapped to the seq_file based
interface of kernfs.
cftype->read_map() doesn't add any value and being replaced with
->read_seq_string(). Update cpu_stats_show() and cpuacct_stats_show()
accordingly.
This patch doesn't make any visible behavior changes.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org>
Tejun Heo [Fri, 29 Nov 2013 15:42:59 +0000 (10:42 -0500)]
cgroup: don't guarantee cgroup.procs is sorted if sane_behavior
For some reason, tasks and cgroup.procs guarantee that the result is
sorted. This is the only reason this whole pidlist logic is necessary
instead of just iterating through sorted member tasks. We can't do
anything about the existing interface but at least ensure that such
expectation doesn't exist for the new interface so that pidlist logic
may be removed in the distant future.
This patch scrambles the sort order if sane_behavior so that the
output is usually not sorted in the new interface.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
Tejun Heo [Fri, 29 Nov 2013 15:42:59 +0000 (10:42 -0500)]
cgroup: remove cgroup_pidlist->use_count
After the recent changes, pidlist ref is held only between
cgroup_pidlist_start() and cgroup_pidlist_stop() during which
cgroup->pidlist_mutex is also held. IOW, the reference count is
redundant now. While in use, it's always one and pidlist_mutex is
held - holding the mutex has exactly the same protection.
This patch collapses destroy_dwork queueing into cgroup_pidlist_stop()
so that pidlist_mutex is not released inbetween and drops
pidlist->use_count.
This patch shouldn't introduce any behavior changes.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
Tejun Heo [Fri, 29 Nov 2013 15:42:59 +0000 (10:42 -0500)]
cgroup: load and release pidlists from seq_file start and stop respectively
Currently, pidlists are reference counted from file open and release
methods. This means that holding onto an open file may waste memory
and reads may return data which is very stale. Both aren't critical
because pidlists are keyed and shared per namespace and, well, the
user isn't supposed to have large delay between open and reads.
cgroup is planned to be converted to use kernfs and it'd be best if we
can stick to just the seq_file operations - start, next, stop and
show. This can be achieved by loading pidlist on demand from start
and release with time delay from stop, so that consecutive reads don't
end up reloading the pidlist on each iteration. This would remove the
need for hooking into open and release while also avoiding issues with
holding onto pidlist for too long.
The previous patches implemented delayed release and restructured
pidlist handling so that pidlists can be loaded and released from
seq_file start / stop. This patch actually moves pidlist load to
start and release to stop.
This means that pidlist is pinned only between start and stop and may
go away between two consecutive read calls if the two calls are apart
by more than CGROUP_PIDLIST_DESTROY_DELAY. cgroup_pidlist_start()
thus can't re-use the stored cgroup_pid_list_open_file->pidlist
directly. During start, it's only used as a hint indicating whether
this is the first start after open or not and pidlist is always looked
up or created.
pidlist_mutex locking and reference counting are moved out of
pidlist_array_load() so that pidlist_array_load() can perform lookup
and creation atomically. While this enlarges the area covered by
pidlist_mutex, given how the lock is used, it's highly unlikely to be
noticeable.
v2: Refreshed on top of the updated "cgroup: introduce struct
cgroup_pidlist_open_file".
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
Tejun Heo [Fri, 29 Nov 2013 15:42:59 +0000 (10:42 -0500)]
cgroup: remove cgroup_pidlist->rwsem
cgroup_pidlist locking is needlessly complicated. It has outer
cgroup->pidlist_mutex to protect the list of pidlists associated with
a cgroup and then each pidlist has rwsem to synchronize updates and
reads. Given that the only read access is from seq_file operations
which are always invoked back-to-back, the rwsem is a giant overkill.
All it does is adding unnecessary complexity.
This patch removes cgroup_pidlist->rwsem and protects all accesses to
pidlists belonging to a cgroup with cgroup->pidlist_mutex.
pidlist->rwsem locking is removed if it's nested inside
cgroup->pidlist_mutex; otherwise, it's replaced with
cgroup->pidlist_mutex locking.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
Tejun Heo [Fri, 29 Nov 2013 15:42:59 +0000 (10:42 -0500)]
cgroup: refactor cgroup_pidlist_find()
Rename cgroup_pidlist_find() to cgroup_pidlist_find_create() and
separate out finding proper to cgroup_pidlist_find(). Also, move
locking to the caller.
This patch is preparation for pidlist restructure and doesn't
introduce any behavior changes.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
Tejun Heo [Fri, 29 Nov 2013 15:42:58 +0000 (10:42 -0500)]
cgroup: introduce struct cgroup_pidlist_open_file
For pidlist files, seq_file->private pointed to the loaded
cgroup_pidlist; however, pidlist loading is planned to be moved to
cgroup_pidlist_start() for kernfs conversion and seq_file->private
needs to carry more information from open to allow that.
This patch introduces struct cgroup_pidlist_open_file which contains
type, cgrp and pidlist and updates pidlist seq_file->private to point
to it using seq_open_private() and seq_release_private(). Note that
this eventually will be replaced by kernfs_open_file.
While this patch makes more information available to seq_file
operations, they don't use it yet and this patch doesn't introduce any
behavior changes except for allocation of the extra private struct.
v2: use __seq_open_private() instead of seq_open_private() for brevity
as suggested by Li.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
Tejun Heo [Fri, 29 Nov 2013 15:42:58 +0000 (10:42 -0500)]
cgroup: implement delayed destruction for cgroup_pidlist
Currently, pidlists are reference counted from file open and release
methods. This means that holding onto an open file may waste memory
and reads may return data which is very stale. Both aren't critical
because pidlists are keyed and shared per namespace and, well, the
user isn't supposed to have large delay between open and reads.
cgroup is planned to be converted to use kernfs and it'd be best if we
can stick to just the seq_file operations - start, next, stop and
show. This can be achieved by loading pidlist on demand from start
and release with time delay from stop, so that consecutive reads don't
end up reloading the pidlist on each iteration. This would remove the
need for hooking into open and release while also avoiding issues with
holding onto pidlist for too long.
This patch implements delayed release of pidlist. As pidlists could
be lingering on cgroup removal waiting for the timer to expire, cgroup
free path needs to queue the destruction work item immediately and
flush. As those work items are self-destroying, each work item can't
be flushed directly. A new workqueue - cgroup_pidlist_destroy_wq - is
added to serve as flush domain.
Note that this patch just adds delayed release on top of the current
implementation and doesn't change where pidlist is loaded and
released. Following patches will make those changes.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
Tejun Heo [Fri, 29 Nov 2013 15:42:58 +0000 (10:42 -0500)]
cgroup: don't skip seq_open on write only opens on pidlist files
Currently, cgroup_pidlist_open() skips seq_open() and pidlist loading
if the file is opened write-only, which is a sensible optimization as
pidlist loading can be costly and there often are occasions where
tasks or cgroup.procs is opened write-only. However, pidlist init and
release are planned to be moved to cgroup_pidlist_start/stop()
respectively which would make this optimization unnecessary.
This patch removes the optimization and always fully initializes
pidlist files regardless of open mode. This will help moving pidlist
handling to start/stop by unifying rw paths and removes the need for
specifying cftype->release() in addition to .release in
cgroup_pidlist_operations as file->f_op is now always overridden. As
pidlist files were the only user of cftype->release(), the next patch
will remove the method.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
Tejun Heo [Wed, 27 Nov 2013 23:17:27 +0000 (18:17 -0500)]
cgroup: Merge branch 'for-3.13-fixes' into for-3.14
Pull to receive e605b36575e8 ("cgroup: fix cgroup_subsys_state leak
for seq_files") as for-3.14 is scheduled to have a lot of changes
which depend on it.
Tejun Heo [Wed, 27 Nov 2013 23:16:21 +0000 (18:16 -0500)]
cgroup: fix cgroup_subsys_state leak for seq_files
If a cgroup file implements either read_map() or read_seq_string(),
such file is served using seq_file by overriding file->f_op to
cgroup_seqfile_operations, which also overrides the release method to
single_release() from cgroup_file_release().
Because cgroup_file_open() didn't use to acquire any resources, this
used to be fine, but since f7d58818ba42 ("cgroup: pin
cgroup_subsys_state when opening a cgroupfs file"), cgroup_file_open()
pins the css (cgroup_subsys_state) which is put by
cgroup_file_release(). The patch forgot to update the release path
for seq_files and each open/release cycle leaks a css reference.
Fix it by updating cgroup_file_release() to also handle seq_files and
using it for seq_file release path too.
Which reports that we take mems_allowed_seq with interrupts enabled. A
little digging found that this can only be from
cpuset_change_task_nodemask().
This is an actual deadlock because an interrupt doing an allocation will
hit get_mems_allowed()->...->__read_seqcount_begin(), which will spin
forever waiting for the write side to complete.
Cc: John Stultz <john.stultz@linaro.org> Cc: Mel Gorman <mgorman@suse.de> Reported-by: Juri Lelli <juri.lelli@gmail.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Tested-by: Juri Lelli <juri.lelli@gmail.com> Acked-by: Li Zefan <lizefan@huawei.com> Acked-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Tejun Heo <tj@kernel.org> Cc: stable@vger.kernel.org
Tejun Heo [Fri, 22 Nov 2013 23:32:25 +0000 (18:32 -0500)]
cgroup: Merge branch 'memcg_event' into for-3.14
Merge v3.12 based patch series to move cgroup_event implementation to
memcg into for-3.14. The following two commits cause a conflict in
kernel/cgroup.c
Each patch removes a struct definition from kernel/cgroup.c. As the
two are adjacent, they cause a context conflict. Easily resolved by
removing both structs.
Tejun Heo [Fri, 22 Nov 2013 23:20:44 +0000 (18:20 -0500)]
cgroup: unexport cgroup_css() and remove __file_cft()
Now that cgroup_event is made memcg specific, the temporarily exported
functions are no longer necessary. Unexport cgroup_css() and remove
__file_cft() which doesn't have any user left.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Tejun Heo [Fri, 22 Nov 2013 23:20:44 +0000 (18:20 -0500)]
memcg: rename cgroup_event to mem_cgroup_event
cgroup_event is only available in memcg now. Let's brand it that way.
While at it, add a comment encouraging deprecation of the feature and
remove the respective section from cgroup documentation.
This patch is cosmetic.
v3: Typo update as per Li Zefan.
v2: Index in cgroups.txt updated accordingly as suggested by Li Zefan.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.cz>
Tejun Heo [Fri, 22 Nov 2013 23:20:43 +0000 (18:20 -0500)]
memcg: make cgroup_event deal with mem_cgroup instead of cgroup_subsys_state
cgroup_event is now memcg specific. Replace cgroup_event->css with
->memcg and convert [un]register_event() callbacks to take mem_cgroup
pointer instead of cgroup_subsys_state one. This simplifies the code
slightly and makes css_to_vmpressure() unnecessary which is removed.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.cz>
Tejun Heo [Fri, 22 Nov 2013 23:20:43 +0000 (18:20 -0500)]
memcg: remove cgroup_event->cft
The only use of cgroup_event->cft is distinguishing "usage_in_bytes"
and "memsw.usgae_in_bytes" for mem_cgroup_usage_[un]register_event(),
which can be done by adding an explicit argument to the function and
implementing two wrappers so that the two cases can be distinguished
from the function alone.
Remove cgroup_event->cft and the related code including
[un]register_events() methods.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.cz>
Tejun Heo [Fri, 22 Nov 2013 23:20:43 +0000 (18:20 -0500)]
cgroup, memcg: move cgroup->event_list[_lock] and event callbacks into memcg
cgroup_event is being moved from cgroup core to memcg and the
implementation is already moved by the previous patch. This patch
moves the data fields and callbacks.
* cgroup->event_list[_lock] are moved to mem_cgroup.
* cftype->[un]register_event() are moved to cgroup_event. This makes
it impossible for individual cftype definitions to specify their
event callbacks. This is worked around by simply hard-coding
filename to event callback mapping in cgroup_write_event_control().
This is awkward and inflexible, which is actually desirable given
that we don't want to grow more usages of this feature.
* eventfd_ctx declaration is removed from cgroup.h, which makes
vmpressure.h miss eventfd_ctx declaration. Include eventfd.h from
vmpressure.h.
v2: Use file name from dentry instead of cftype. This will allow
removing all cftype handling in the function.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Balbir Singh <bsingharora@gmail.com>
Tejun Heo [Fri, 22 Nov 2013 23:20:42 +0000 (18:20 -0500)]
memcg: cgroup_write_event_control() now knows @css is for memcg
@css for cgroup_write_event_control() is now always for memcg and the
target file should be a memcg file too. Drop code which assumes @css
is dummy_css and the target file may belong to different subsystems.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Tejun Heo [Fri, 22 Nov 2013 23:20:42 +0000 (18:20 -0500)]
cgroup, memcg: move cgroup_event implementation to memcg
cgroup_event is way over-designed and tries to build a generic
flexible event mechanism into cgroup - fully customizable event
specification for each user of the interface. This is utterly
unnecessary and overboard especially in the light of the planned
unified hierarchy as there's gonna be single agent. Simply generating
events at fixed points, or if that's too restrictive, configureable
cadence or single set of configureable points should be enough.
Thankfully, memcg is the only user and gets to keep it. Replacing it
with something simpler on sane_behavior is strongly recommended.
This patch moves cgroup_event and "cgroup.event_control"
implementation to mm/memcontrol.c. Clearing of events on cgroup
destruction is moved from cgroup_destroy_locked() to
mem_cgroup_css_offline(), which shouldn't make any noticeable
difference.
cgroup_css() and __file_cft() are exported to enable the move;
however, this will soon be reverted once the event code is updated to
be memcg specific.
Note that "cgroup.event_control" will now exist only on the hierarchy
with memcg attached to it. While this change is visible to userland,
it is unlikely to be noticeable as the file has never been meaningful
outside memcg.
Aside from the above change, this is pure code relocation.
v2: Per Li Zefan's comments, init/Kconfig updated accordingly and
poll.h inclusion moved from cgroup.c to memcontrol.c.
Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Balbir Singh <bsingharora@gmail.com>
Tejun Heo [Fri, 22 Nov 2013 22:14:39 +0000 (17:14 -0500)]
cgroup: use a dedicated workqueue for cgroup destruction
Since be44562613851 ("cgroup: remove synchronize_rcu() from
cgroup_diput()"), cgroup destruction path makes use of workqueue. css
freeing is performed from a work item from that point on and a later
commit, ea15f8ccdb430 ("cgroup: split cgroup destruction into two
steps"), moves css offlining to workqueue too.
As cgroup destruction isn't depended upon for memory reclaim, the
destruction work items were put on the system_wq; unfortunately, some
controller may block in the destruction path for considerable duration
while holding cgroup_mutex. As large part of destruction path is
synchronized through cgroup_mutex, when combined with high rate of
cgroup removals, this has potential to fill up system_wq's max_active
of 256.
Also, it turns out that memcg's css destruction path ends up queueing
and waiting for work items on system_wq through work_on_cpu(). If
such operation happens while system_wq is fully occupied by cgroup
destruction work items, work_on_cpu() can't make forward progress
because system_wq is full and other destruction work items on
system_wq can't make forward progress because the work item waiting
for work_on_cpu() is holding cgroup_mutex, leading to deadlock.
This can be fixed by queueing destruction work items on a separate
workqueue. This patch creates a dedicated workqueue -
cgroup_destroy_wq - for this purpose. As these work items shouldn't
have inter-dependencies and mostly serialized by cgroup_mutex anyway,
giving high concurrency level doesn't buy anything and the workqueue's
@max_active is set to 1 so that destruction work items are executed
one by one on each CPU.
Hugh Dickins: Because cgroup_init() is run before init_workqueues(),
cgroup_destroy_wq can't be allocated from cgroup_init(). Do it from a
separate core_initcall(). In the future, we probably want to reorder
so that workqueue init happens before cgroup_init().
Linus Torvalds [Fri, 22 Nov 2013 18:58:14 +0000 (10:58 -0800)]
Merge tag 'ecryptfs-3.13-rc1-quiet-checkers' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs
Pull minor eCryptfs fix from Tyler Hicks:
"Quiet static checkers by removing unneeded conditionals"
* tag 'ecryptfs-3.13-rc1-quiet-checkers' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs:
eCryptfs: file->private_data is always valid
Linus Torvalds [Fri, 22 Nov 2013 18:57:31 +0000 (10:57 -0800)]
Merge tag 'sound-fix2-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull second set of sound fixes from Takashi Iwai:
"A collection of small fixes in HD-audio quirks and runtime PM, ASoC
rcar, abs8500 and other codecs. Most of commits are for stable
kernels, too"
* tag 'sound-fix2-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: hda - Set current_headset_type to ALC_HEADSET_TYPE_ENUM (janitorial)
ALSA: hda - Provide missing pin configs for VAIO with ALC260
ALSA: hda - Add headset quirk for Dell Inspiron 3135
ALSA: hda - Fix the headphone jack detection on Sony VAIO TX
ALSA: hda - Fix missing bass speaker on ASUS N550
ALSA: hda - Fix unbalanced runtime PM notification at resume
ASoC: arizona: Set FLL to free-run before disabling
ALSA: hda - A casual Dell Headset quirk
ASoC: rcar: fixup dma_async_issue_pending() timing
ASoC: rcar: off by one in rsnd_scu_set_route()
ASoC: wm5110: Add post SYSCLK register patch for rev D chip
ASoC: ab8500: Revert to using custom I/O functions
ALSA: hda - Also enable mute/micmute LED control for "Lenovo dock" fixup
ALSA: firewire-lib: include sound/asound.h to refer to snd_pcm_format_t
ALSA: hda - Select FW_LOADER from CONFIG_SND_HDA_CODEC_CA0132_DSP
ALSA: hda - Enable mute/mic-mute LEDs for more Thinkpads with Realtek codec
ASoC: rcar: fixup mod access before checking
Linus Torvalds [Fri, 22 Nov 2013 18:56:11 +0000 (10:56 -0800)]
Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
Pull DRM fixes from Dave Airlie:
"I was going to leave this until post -rc1 but sysfs fixes broke
hotplug in userspace, so I had to fix it harder, otherwise a set of
pulls from intel, radeon and vmware,
The vmware/ttm changes are bit larger but since its early and they are
unlikely to break anything else I put them in, it lets vmware work
with dri3"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (36 commits)
drm/sysfs: fix hotplug regression since lifetime changes
drm/exynos: g2d: fix memory leak to userptr
drm/i915: Fix gen3 self-refresh watermarks
drm/ttm: Remove set_need_resched from the ttm fault handler
drm/ttm: Don't move non-existing data
drm/radeon: hook up backlight functions for CI and KV family.
drm/i915: Replicate BIOS eDP bpp clamping hack for hsw
drm/i915: Do not enable package C8 on unsupported hardware
drm/i915: Hold pc8 lock around toggling pc8.gpu_idle
drm/i915: encoder->get_config is no longer optional
drm/i915/tv: add ->get_config callback
drm/radeon/cik: Add macrotile mode array query
drm/radeon/cik: Return backend map information to userspace
drm/vmwgfx: Make vmwgfx dma buffers prime aware
drm/vmwgfx: Make surfaces prime-aware
drm/vmwgfx: Hook up the prime ioctls
drm/ttm: Add a minimal prime implementation for ttm base objects
drm/vmwgfx: Fix false lockdep warning
drm/ttm: Allow execbuf util reserves without ticket
drm/i915: restore the early forcewake cleanup
...
Linus Torvalds [Fri, 22 Nov 2013 18:53:47 +0000 (10:53 -0800)]
Merge tag 'pci-v3.13-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI updates from Bjorn Helgaas:
"Miscellaneous
- Remove duplicate disable from pcie_portdrv_remove() (Yinghai Lu)
- Fix whitespace, capitalization, and spelling errors (Bjorn Helgaas)"
* tag 'pci-v3.13-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
PCI: Remove duplicate pci_disable_device() from pcie_portdrv_remove()
PCI: Fix whitespace, capitalization, and spelling errors
Linus Torvalds [Fri, 22 Nov 2013 18:52:03 +0000 (10:52 -0800)]
Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
Pull SCSI target updates from Nicholas Bellinger:
"Things have been quiet this round with mostly bugfixes, percpu
conversions, and other minor iscsi-target conformance testing changes.
The highlights include:
- Add demo_mode_discovery attribute for iscsi-target (Thomas)
- Convert tcm_fc(FCoE) to use percpu-ida pre-allocation
- Add send completion interrupt coalescing for ib_isert
- Convert target-core to use percpu-refcounting for se_lun
- Fix mutex_trylock usage bug in iscsit_increment_maxcmdsn
- tcm_loop updates (Hannes)
- target-core ALUA cleanups + prep for v3.14 SCSI Referrals support (Hannes)
v3.14 is currently shaping to be a busy development cycle in target
land, with initial support for T10 Referrals and T10 DIF currently on
the roadmap"
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (40 commits)
iscsi-target: chap auth shouldn't match username with trailing garbage
iscsi-target: fix extract_param to handle buffer length corner case
iscsi-target: Expose default_erl as TPG attribute
target_core_configfs: split up ALUA supported states
target_core_alua: Make supported states configurable
target_core_alua: Store supported ALUA states
target_core_alua: Rename ALUA_ACCESS_STATE_OPTIMIZED
target_core_alua: spellcheck
target core: rename (ex,im)plict -> (ex,im)plicit
percpu-refcount: Add percpu-refcount.o to obj-y
iscsi-target: Do not reject non-immediate CmdSNs exceeding MaxCmdSN
iscsi-target: Convert iscsi_session statistics to atomic_long_t
target: Convert se_device statistics to atomic_long_t
target: Fix delayed Task Aborted Status (TAS) handling bug
iscsi-target: Reject unsupported multi PDU text command sequence
ib_isert: Avoid duplicate iscsit_increment_maxcmdsn call
iscsi-target: Fix mutex_trylock usage in iscsit_increment_maxcmdsn
target: Core does not need blkdev.h
target: Pass through I/O topology for block backstores
iser-target: Avoid using FRMR for single dma entry requests
...
Linus Torvalds [Fri, 22 Nov 2013 18:49:14 +0000 (10:49 -0800)]
Merge tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging
Pull hwmon fixes from Guenter Roeck:
- acpi_power_meter: Fix return value check from call to
acpi_bus_get_device
- nct6775: Fix/improve NCT6791 support
- lm75: Add support for GMT G751
* tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
hwmon: (acpi_power_meter) Fix acpi_bus_get_device() return value check
hwmon: (nct6775) NCT6791 supports weight control only for CPUFAN
hwmon: (nct6775) Monitor additional temperature registers
hwmon: (lm75) Add support for GMT G751 chip
1) Fix memory leaks and other issues in mwifiex driver, from Amitkumar
Karwar.
2) skb_segment() can choke on packets using frag lists, fix from
Herbert Xu with help from Eric Dumazet and others.
3) IPv4 output cached route instantiation properly handles races
involving two threads trying to install the same route, but we
forgot to propagate this logic to input routes as well. Fix from
Alexei Starovoitov.
4) Put protections in place to make sure that recvmsg() paths never
accidently copy uninitialized memory back into userspace and also
make sure that we never try to use more that sockaddr_storage for
building the on-kernel-stack copy of a sockaddr. Fixes from Hannes
Frederic Sowa.
5) R8152 driver transmit flow bug fixes from Hayes Wang.
6) Fix some minor fallouts from genetlink changes, from Johannes Berg
and Michael Opdenacker.
7) AF_PACKET sendmsg path can race with netdevice unregister notifier,
fix by using RCU to make sure the network device doesn't go away
from under us. Fix from Daniel Borkmann.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (43 commits)
gso: handle new frag_list of frags GRO packets
genetlink: fix genl_set_err() group ID
genetlink: fix genlmsg_multicast() bug
packet: fix use after free race in send path when dev is released
xen-netback: stop the VIF thread before unbinding IRQs
wimax: remove dead code
net/phy: Add the autocross feature for forced links on VSC82x4
net/phy: Add VSC8662 support
net/phy: Add VSC8574 support
net/phy: Add VSC8234 support
net: add BUG_ON if kernel advertises msg_namelen > sizeof(struct sockaddr_storage)
net: rework recvmsg handler msg_name and msg_namelen logic
bridge: flush br's address entry in fdb when remove the
net: core: Always propagate flag changes to interfaces
ipv4: fix race in concurrent ip_route_input_slow()
r8152: fix incorrect type in assignment
r8152: support stopping/waking tx queue
r8152: modify the tx flow
r8152: fix tx/rx memory overflow
netfilter: ebt_ip6: fix source and destination matching
...
Linus Torvalds [Fri, 22 Nov 2013 17:56:51 +0000 (09:56 -0800)]
Merge branch 'fixes' of git://git.linaro.org/people/rmk/linux-arm
Pull ARM fixes from Russell King:
"Some small fixes for this merge window, most of them quite self
explanatory - the biggest thing here is a fix for the ARMv7 LPAE
suspend/resume support"
* 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
ARM: 7894/1: kconfig: select GENERIC_CLOCKEVENTS if HAVE_ARM_ARCH_TIMER
ARM: 7893/1: bitops: only emit .arch_extension mp if CONFIG_SMP
ARM: 7892/1: Fix warning for V7M builds
ARM: 7888/1: seccomp: not compatible with ARM OABI
ARM: 7886/1: make OABI default to off
ARM: 7885/1: Save/Restore 64-bit TTBR registers on LPAE suspend/resume
ARM: 7884/1: mm: Fix ECC mem policy printk
ARM: 7883/1: fix mov to mvn conversion in case of 64 bit phys_addr_t and BE
ARM: 7882/1: mm: fix __phys_to_virt to work with 64 bit phys_addr_t in BE case
ARM: 7881/1: __fixup_smp read of SCU config should do byteswap in BE case
ARM: Fix nommu.c build warning
Linus Torvalds [Fri, 22 Nov 2013 16:41:17 +0000 (08:41 -0800)]
Merge branch 'for-3.13' of git://linux-nfs.org/~bfields/linux
Pull nfsd bugfixes from Bruce Fields:
"A couple nfsd bugfixes"
* 'for-3.13' of git://linux-nfs.org/~bfields/linux:
nfsd4: fix xdr decoding of large non-write compounds
nfsd: make sure to balance get/put_write_access
nfsd: split up nfsd_setattr
Linus Torvalds [Fri, 22 Nov 2013 16:39:44 +0000 (08:39 -0800)]
Merge tag 'gfs2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-fixes
Pull GFS2 fixes from Steven Whitehouse:
"A couple of small, but important bug fixes for GFS2. The first one
fixes a possible NULL pointer dereference, and the second one resolves
a reference counting issue in one of the lesser used paths through
atomic_open"
* tag 'gfs2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-fixes:
GFS2: Fix ref count bug relating to atomic_open
GFS2: fix potential NULL pointer dereference
Linus Torvalds [Fri, 22 Nov 2013 16:38:55 +0000 (08:38 -0800)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
"Almost all of these are bug fixes. Dave Sterba's documentation update
is the big exception because he removed our promises to set any
machine running Btrfs on fire"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Documentation: filesystems: update btrfs tools section
Documentation: filesystems: add new btrfs mount options
btrfs: update kconfig help text
btrfs: fix bio_size_ok() for max_sectors > 0xffff
btrfs: Use trace condition for get_extent tracepoint
btrfs: fix typo in the log message
Btrfs: fix list delete warning when removing ordered root from the list
Btrfs: print bytenr instead of page pointer in check-int
Btrfs: remove dead codes from ctree.h
Btrfs: don't wait for ordered data outside desired range
Btrfs: fix lockdep error in async commit
Btrfs: avoid heavy operations in btrfs_commit_super
Btrfs: fix __btrfs_start_workers retval
Btrfs: disable online raid-repair on ro mounts
Btrfs: do not inc uncorrectable_errors counter on ro scrubs
Btrfs: only drop modified extents if we logged the whole inode
Btrfs: make sure to copy everything if we rename
Btrfs: don't BUG_ON() if we get an error walking backrefs
Linus Torvalds [Fri, 22 Nov 2013 16:37:47 +0000 (08:37 -0800)]
Merge tag 'xfs-for-linus-v3.13-rc1-2' of git://oss.sgi.com/xfs/xfs
Pull second xfs update from Ben Myers:
"There are a couple of patches that I wasn't quite sure about in time
for our initial 3.13 pull request, a bugfix, and an update to add Dave
to MAINTAINERS:
Here we have a performance fix for inode iversion, increased inode
cluster size for v5 superblock filesystems, a fix for error handling
in xfs_bmap_add_attrfork, and a MAINTAINERS update to add Dave"
* tag 'xfs-for-linus-v3.13-rc1-2' of git://oss.sgi.com/xfs/xfs:
xfs: open code inc_inode_iversion when logging an inode
xfs: increase inode cluster size for v5 filesystems
xfs: fix unlock in xfs_bmap_add_attrfork
xfs: update maintainers
Linus Torvalds [Fri, 22 Nov 2013 16:10:34 +0000 (08:10 -0800)]
Merge branch 'slab/next' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux
Pull SLAB changes from Pekka Enberg:
"The patches from Joonsoo Kim switch mm/slab.c to use 'struct page' for
slab internals similar to mm/slub.c. This reduces memory usage and
improves performance:
https://lkml.org/lkml/2013/10/16/155
Rest of the changes are bug fixes from various people"
* 'slab/next' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux: (21 commits)
mm, slub: fix the typo in mm/slub.c
mm, slub: fix the typo in include/linux/slub_def.h
slub: Handle NULL parameter in kmem_cache_flags
slab: replace non-existing 'struct freelist *' with 'void *'
slab: fix to calm down kmemleak warning
slub: proper kmemleak tracking if CONFIG_SLUB_DEBUG disabled
slab: rename slab_bufctl to slab_freelist
slab: remove useless statement for checking pfmemalloc
slab: use struct page for slab management
slab: replace free and inuse in struct slab with newly introduced active
slab: remove SLAB_LIMIT
slab: remove kmem_bufctl_t
slab: change the management method of free objects of the slab
slab: use __GFP_COMP flag for allocating slab pages
slab: use well-defined macro, virt_to_slab()
slab: overloading the RCU head over the LRU for RCU free
slab: remove cachep in struct slab_rcu
slab: remove nodeid in struct slab
slab: remove colouroff in struct slab
slab: change return type of kmem_getpages() to struct page
...
Linus Torvalds [Fri, 22 Nov 2013 16:07:11 +0000 (08:07 -0800)]
Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
Pull third set of powerpc updates from Benjamin Herrenschmidt:
"This is a small collection of random bug fixes and a few improvements
of Oops output which I deemed valuable enough to include as well.
The fixes are essentially recent build breakage and regressions, and a
couple of older bugs such as the DTL log duplication, the EEH issue
with PCI_COMMAND_MASTER and the problem with small contexts passed to
get/set_context with VSX enabled"
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc/signals: Mark VSX not saved with small contexts
powerpc/pseries: Fix SMP=n build of rng.c
powerpc: Make cpu_to_chip_id() available when SMP=n
powerpc/vio: Fix a dma_mask issue of vio
powerpc: booke: Fix build failures
powerpc: ppc64 address space capped at 32TB, mmap randomisation disabled
powerpc: Only print PACATMSCRATCH in oops when TM is active
powerpc/pseries: Duplicate dtl entries sometimes sent to userspace
powerpc: Remove a few lines of oops output
powerpc: Print DAR and DSISR on machine check oopses
powerpc: Fix __get_user_pages_fast() irq handling
powerpc/eeh: More accurate log
powerpc/eeh: Enable PCI_COMMAND_MASTER for PCI bridges
ALSA: hda - Set current_headset_type to ALC_HEADSET_TYPE_ENUM (janitorial)
current_headset_type should be of the HEADSET_TYPE enum, not the
HEADSET_MODE enum. Since ALC_HEADSET_TYPE_UNKNOWN and ALC_HEADSET_MODE_UNKNOWN
are both 0, this patch is just janitorial.
Signed-off-by: David Henningsson <david.henningsson@canonical.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
Takashi Iwai [Fri, 22 Nov 2013 07:06:36 +0000 (08:06 +0100)]
ALSA: hda - Provide missing pin configs for VAIO with ALC260
Some models (or maybe depending on BIOS version) of Sony VAIO with
ALC260 give no proper pin configurations as default, resulting in the
non-working speaker, etc. Just provide the whole pin configurations
via a fixup.
Reported-by: Matthew Markus <mmarkus@hearit.co> Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
Linus Torvalds [Fri, 22 Nov 2013 05:32:38 +0000 (21:32 -0800)]
Merge branch 'akpm' (fixes from Andrew)
Merge patches from Andrew Morton:
"13 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm: place page->pmd_huge_pte to right union
MAINTAINERS: add keyboard driver to Hyper-V file list
x86, mm: do not leak page->ptl for pmd page tables
ipc,shm: correct error return value in shmctl (SHM_UNLOCK)
mm, mempolicy: silence gcc warning
block/partitions/efi.c: fix bound check
ARM: drivers/rtc/rtc-at91rm9200.c: disable interrupts at shutdown
mm: hugetlbfs: fix hugetlbfs optimization
kernel: remove CONFIG_USE_GENERIC_SMP_HELPERS cleanly
ipc,shm: fix shm_file deletion races
mm: thp: give transparent hugepage code a separate copy_page
checkpatch: fix "Use of uninitialized value" warnings
configfs: fix race between dentry put and lookup
Linus Torvalds [Fri, 22 Nov 2013 03:46:00 +0000 (19:46 -0800)]
Merge branch 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
"In this patchset, we finally get an SELinux update, with Paul Moore
taking over as maintainer of that code.
Also a significant update for the Keys subsystem, as well as
maintenance updates to Smack, IMA, TPM, and Apparmor"
and since I wanted to know more about the updates to key handling,
here's the explanation from David Howells on that:
"Okay. There are a number of separate bits. I'll go over the big bits
and the odd important other bit, most of the smaller bits are just
fixes and cleanups. If you want the small bits accounting for, I can
do that too.
(1) Keyring capacity expansion.
KEYS: Consolidate the concept of an 'index key' for key access
KEYS: Introduce a search context structure
KEYS: Search for auth-key by name rather than target key ID
Add a generic associative array implementation.
KEYS: Expand the capacity of a keyring
Several of the patches are providing an expansion of the capacity of a
keyring. Currently, the maximum size of a keyring payload is one page.
Subtract a small header and then divide up into pointers, that only gives
you ~500 pointers on an x86_64 box. However, since the NFS idmapper uses
a keyring to store ID mapping data, that has proven to be insufficient to
the cause.
Whatever data structure I use to handle the keyring payload, it can only
store pointers to keys, not the keys themselves because several keyrings
may point to a single key. This precludes inserting, say, and rb_node
struct into the key struct for this purpose.
I could make an rbtree of records such that each record has an rb_node
and a key pointer, but that would use four words of space per key stored
in the keyring. It would, however, be able to use much existing code.
I selected instead a non-rebalancing radix-tree type approach as that
could have a better space-used/key-pointer ratio. I could have used the
radix tree implementation that we already have and insert keys into it by
their serial numbers, but that means any sort of search must iterate over
the whole radix tree. Further, its nodes are a bit on the capacious side
for what I want - especially given that key serial numbers are randomly
allocated, thus leaving a lot of empty space in the tree.
So what I have is an associative array that internally is a radix-tree
with 16 pointers per node where the index key is constructed from the key
type pointer and the key description. This means that an exact lookup by
type+description is very fast as this tells us how to navigate directly to
the target key.
I made the data structure general in lib/assoc_array.c as far as it is
concerned, its index key is just a sequence of bits that leads to a
pointer. It's possible that someone else will be able to make use of it
also. FS-Cache might, for example.
(2) Mark keys as 'trusted' and keyrings as 'trusted only'.
KEYS: verify a certificate is signed by a 'trusted' key
KEYS: Make the system 'trusted' keyring viewable by userspace
KEYS: Add a 'trusted' flag and a 'trusted only' flag
KEYS: Separate the kernel signature checking keyring from module signing
These patches allow keys carrying asymmetric public keys to be marked as
being 'trusted' and allow keyrings to be marked as only permitting the
addition or linkage of trusted keys.
Keys loaded from hardware during kernel boot or compiled into the kernel
during build are marked as being trusted automatically. New keys can be
loaded at runtime with add_key(). They are checked against the system
keyring contents and if their signatures can be validated with keys that
are already marked trusted, then they are marked trusted also and can
thus be added into the master keyring.
Patches from Mimi Zohar make this usable with the IMA keyrings also.
(3) Remove the date checks on the key used to validate a module signature.
X.509: Remove certificate date checks
It's not reasonable to reject a signature just because the key that it was
generated with is no longer valid datewise - especially if the kernel
hasn't yet managed to set the system clock when the first module is
loaded - so just remove those checks.
(4) Make it simpler to deal with additional X.509 being loaded into the kernel.
KEYS: Load *.x509 files into kernel keyring
KEYS: Have make canonicalise the paths of the X.509 certs better to deduplicate
The builder of the kernel now just places files with the extension ".x509"
into the kernel source or build trees and they're concatenated by the
kernel build and stuffed into the appropriate section.
(5) Add support for userspace kerberos to use keyrings.
KEYS: Add per-user_namespace registers for persistent per-UID kerberos caches
KEYS: Implement a big key type that can save to tmpfs
Fedora went to, by default, storing kerberos tickets and tokens in tmpfs.
We looked at storing it in keyrings instead as that confers certain
advantages such as tickets being automatically deleted after a certain
amount of time and the ability for the kernel to get at these tokens more
easily.
To make this work, two things were needed:
(a) A way for the tickets to persist beyond the lifetime of all a user's
sessions so that cron-driven processes can still use them.
The problem is that a user's session keyrings are deleted when the
session that spawned them logs out and the user's user keyring is
deleted when the UID is deleted (typically when the last log out
happens), so neither of these places is suitable.
I've added a system keyring into which a 'persistent' keyring is
created for each UID on request. Each time a user requests their
persistent keyring, the expiry time on it is set anew. If the user
doesn't ask for it for, say, three days, the keyring is automatically
expired and garbage collected using the existing gc. All the kerberos
tokens it held are then also gc'd.
(b) A key type that can hold really big tickets (up to 1MB in size).
The problem is that Active Directory can return huge tickets with lots
of auxiliary data attached. We don't, however, want to eat up huge
tracts of unswappable kernel space for this, so if the ticket is
greater than a certain size, we create a swappable shmem file and dump
the contents in there and just live with the fact we then have an
inode and a dentry overhead. If the ticket is smaller than that, we
slap it in a kmalloc()'d buffer"
* 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (121 commits)
KEYS: Fix keyring content gc scanner
KEYS: Fix error handling in big_key instantiation
KEYS: Fix UID check in keyctl_get_persistent()
KEYS: The RSA public key algorithm needs to select MPILIB
ima: define '_ima' as a builtin 'trusted' keyring
ima: extend the measurement list to include the file signature
kernel/system_certificate.S: use real contents instead of macro GLOBAL()
KEYS: fix error return code in big_key_instantiate()
KEYS: Fix keyring quota misaccounting on key replacement and unlink
KEYS: Fix a race between negating a key and reading the error set
KEYS: Make BIG_KEYS boolean
apparmor: remove the "task" arg from may_change_ptraced_domain()
apparmor: remove parent task info from audit logging
apparmor: remove tsk field from the apparmor_audit_struct
apparmor: fix capability to not use the current task, during reporting
Smack: Ptrace access check mode
ima: provide hash algo info in the xattr
ima: enable support for larger default filedata hash algorithms
ima: define kernel parameter 'ima_template=' to change configured default
ima: add Kconfig default measurement list template
...
Linus Torvalds [Fri, 22 Nov 2013 03:18:14 +0000 (19:18 -0800)]
Merge git://git.infradead.org/users/eparis/audit
Pull audit updates from Eric Paris:
"Nothing amazing. Formatting, small bug fixes, couple of fixes where
we didn't get records due to some old VFS changes, and a change to how
we collect execve info..."
Fixed conflict in fs/exec.c as per Eric and linux-next.
* git://git.infradead.org/users/eparis/audit: (28 commits)
audit: fix type of sessionid in audit_set_loginuid()
audit: call audit_bprm() only once to add AUDIT_EXECVE information
audit: move audit_aux_data_execve contents into audit_context union
audit: remove unused envc member of audit_aux_data_execve
audit: Kill the unused struct audit_aux_data_capset
audit: do not reject all AUDIT_INODE filter types
audit: suppress stock memalloc failure warnings since already managed
audit: log the audit_names record type
audit: add child record before the create to handle case where create fails
audit: use given values in tty_audit enable api
audit: use nlmsg_len() to get message payload length
audit: use memset instead of trying to initialize field by field
audit: fix info leak in AUDIT_GET requests
audit: update AUDIT_INODE filter rule to comparator function
audit: audit feature to set loginuid immutable
audit: audit feature to only allow unsetting the loginuid
audit: allow unsetting the loginuid (with priv)
audit: remove CONFIG_AUDIT_LOGINUID_IMMUTABLE
audit: loginuid functions coding style
selinux: apply selinux checks on new audit message types
...
I don't know what went wrong, mis-merge or something, but ->pmd_huge_pte
placed in wrong union within struct page.
In original patch[1] it's placed to union with ->lru and ->slab, but in
commit e009bb30c8df ("mm: implement split page table lock for PMD
level") it's in union with ->index and ->freelist.
That union seems also unused for pages with table tables and safe to
re-use, but it's not what I've tested.
Let's move it to original place. It fixes indentation at least. :)
[1] https://lkml.org/lkml/2013/10/7/288
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: 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>
x86, mm: do not leak page->ptl for pmd page tables
There are two code paths how page with pmd page table can be freed:
pmd_free() and pmd_free_tlb().
I've missed the second one and didn't add page table destructor call
there. It leads to leak of page->ptl for pmd page tables, if
dynamically allocated page->ptl is in use.
The patch adds the missed destructor and modifies documentation
accordingly.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reported-by: Andrey Vagin <avagin@openvz.org> Tested-by: Andrey Vagin <avagin@openvz.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jesper Nilsson [Thu, 21 Nov 2013 22:32:08 +0000 (14:32 -0800)]
ipc,shm: correct error return value in shmctl (SHM_UNLOCK)
Commit 2caacaa82a51 ("ipc,shm: shorten critical region for shmctl")
restructured the ipc shm to shorten critical region, but introduced a
path where the return value could be -EPERM, even if the operation
actually was performed.
Before the commit, the err return value was reset by the return value
from security_shm_shmctl() after the if (!ns_capable(...)) statement.
Now, we still exit the if statement with err set to -EPERM, and in the
case of SHM_UNLOCK, it is not reset at all, and used as the return value
from shmctl.
To fix this, we only set err when errors occur, leaving the fallthrough
case alone.
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Davidlohr Bueso <davidlohr@hp.com> Cc: Rik van Riel <riel@redhat.com> Cc: Michel Lespinasse <walken@google.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: <stable@vger.kernel.org> [3.12.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use ARRAY_SIZE instead of sizeof to get proper max for label length.
Since this is just a read out of bounds it's not that bad, but the
problem becomes user-visible eg if one tries to use DEBUG_PAGEALLOC and
DEBUG_RODATA, at least with some enhancements from Hiroshi. Of course
the destination array can contain garbage when we read beyond the end of
source array so that would be another user-visible problem.
Signed-off-by: Antti P Miettinen <amiettinen@nvidia.com> Reviewed-by: Hiroshi Doyu <hdoyu@nvidia.com> Tested-by: Hiroshi Doyu <hdoyu@nvidia.com> Cc: Will Drewry <wad@chromium.org> Cc: Matt Fleming <matt.fleming@intel.com> Acked-by: Davidlohr Bueso <davidlohr@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johan Hovold [Thu, 21 Nov 2013 22:32:04 +0000 (14:32 -0800)]
ARM: drivers/rtc/rtc-at91rm9200.c: disable interrupts at shutdown
Make sure RTC-interrupts are disabled at shutdown.
As the RTC is generally powered by backup power (VDDBU), its interrupts
are not disabled on wake-up, user, watchdog or software reset. This
could cause troubles on other systems (e.g. older kernels) if an
interrupt occurs before a handler has been installed at next boot.
Let us be well-behaved and disable them on clean shutdowns at least (as
do the RTT-based rtc-at91sam9 driver).
Signed-off-by: Johan Hovold <jhovold@gmail.com> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com> Cc: Andrew Victor <linux@maxim.org.za> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrea Arcangeli [Thu, 21 Nov 2013 22:32:02 +0000 (14:32 -0800)]
mm: hugetlbfs: fix hugetlbfs optimization
Commit 7cb2ef56e6a8 ("mm: fix aio performance regression for database
caused by THP") can cause dereference of a dangling pointer if
split_huge_page runs during PageHuge() if there are updates to the
tail_page->private field.
Also it is repeating compound_head twice for hugetlbfs and it is running
compound_head+compound_trans_head for THP when a single one is needed in
both cases.
The new code within the PageSlab() check doesn't need to verify that the
THP page size is never bigger than the smallest hugetlbfs page size, to
avoid memory corruption.
A longstanding theoretical race condition was found while fixing the
above (see the change right after the skip_unlock label, that is
relevant for the compound_lock path too).
By re-establishing the _mapcount tail refcounting for all compound
pages, this also fixes the below problem:
The oops is caused because shm_destroy() calls fput() after dropping the
ipc_lock. fput() clears the file's f_inode, f_path.dentry, and
f_path.mnt, which causes various NULL pointer references in task 2. I
reliably see the oops in task 2 if with shmlock, shmu
This patch fixes the races by:
1) set shm_file=NULL in shm_destroy() while holding ipc_object_lock().
2) modify at risk operations to check shm_file while holding
ipc_object_lock().
Example workloads, which each trigger oops...
Workload 1:
while true; do
id=$(shmget 1 4096)
shm_rmid $id &
shmlock $id &
wait
done
The oops stack shows accessing NULL f_inode due to racing fput:
_raw_spin_lock
shmem_lock
SyS_shmctl
Workload 2:
while true; do
id=$(shmget 1 4096)
shmat $id 4096 &
shm_rmid $id &
wait
done
The oops stack is similar to workload 1 due to NULL f_inode:
touch_atime
shmem_mmap
shm_mmap
mmap_region
do_mmap_pgoff
do_shmat
SyS_shmat
Workload 3:
while true; do
id=$(shmget 1 4096)
shmlock $id
shm_rmid $id &
shmunlock $id &
wait
done
The oops stack shows second fput tripping on an NULL f_inode. The
first fput() completed via from shm_destroy(), but a racing thread did
a get_file() and queued this fput():
locks_remove_flock
__fput
____fput
task_work_run
do_notify_resume
int_signal
Fixes: c2c737a0461e ("ipc,shm: shorten critical region for shmat") Fixes: 2caacaa82a51 ("ipc,shm: shorten critical region for shmctl") Signed-off-by: Greg Thelen <gthelen@google.com> Cc: Davidlohr Bueso <davidlohr@hp.com> Cc: Rik van Riel <riel@redhat.com> Cc: Manfred Spraul <manfred@colorfullife.com> Cc: <stable@vger.kernel.org> # 3.10.17+ 3.11.6+ Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
and a non-hugetlbfs page has no page_hstate(). This works 99% of the
time because page_hstate() determines the hstate from the page order
alone. Since the page order of a THP page matches the default hugetlbfs
page order, it works.
But, if you change the default huge page size on the boot command-line
(say default_hugepagesz=1G), then we might not even *have* a 2MB hstate
so page_hstate() returns null and copy_huge_page() oopses pretty fast
since copy_huge_page() dereferences the hstate:
Mel noticed that the migration code is really the only user of these
functions. This moves all the copy code over to migrate.c and makes
copy_huge_page() work for THP by checking for it explicitly.
I believe the bug was introduced in commit b32967ff101a ("mm: numa: Add
THP migration for the NUMA working set scanning fault case")
[akpm@linux-foundation.org: fix coding-style and comment text, per Naoya Horiguchi] Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Tested-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Perches [Thu, 21 Nov 2013 22:31:57 +0000 (14:31 -0800)]
checkpatch: fix "Use of uninitialized value" warnings
checkpatch is currently confused about some complex macros and references
undefined variables $stat and $cond.
Make sure these are defined before using them.
Signed-off-by: Joe Perches <joe@perches.com> Reported-by: Gerhard Sittig <gsi@denx.de> Acked-by: Andy Whitcroft <apw@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Junxiao Bi [Thu, 21 Nov 2013 22:31:56 +0000 (14:31 -0800)]
configfs: fix race between dentry put and lookup
A race window in configfs, it starts from one dentry is UNHASHED and end
before configfs_d_iput is called. In this window, if a lookup happen,
since the original dentry was UNHASHED, so a new dentry will be
allocated, and then in configfs_attach_attr(), sd->s_dentry will be
updated to the new dentry. Then in configfs_d_iput(),
BUG_ON(sd->s_dentry != dentry) will be triggered and system panic.
sys_open: sys_close:
... fput
dput
dentry_kill
__d_drop <--- dentry unhashed here,
but sd->dentry still point
to this dentry.
lookup_real
configfs_lookup
configfs_attach_attr---> update sd->s_dentry
to new allocated dentry here.
To fix it, change configfs_d_iput to not update sd->s_dentry if
sd->s_count > 2, that means there are another dentry is using the sd
beside the one that is going to be put. Use configfs_dirent_lock in
configfs_attach_attr to sync with configfs_d_iput.
With the following steps, you can reproduce the bug.
1. enable ocfs2, this will mount configfs at /sys/kernel/config and
fill configure in it.
2. run the following script.
while [ 1 ]; do cat /sys/kernel/config/cluster/$your_cluster_name/idle_timeout_ms > /dev/null; done &
while [ 1 ]; do cat /sys/kernel/config/cluster/$your_cluster_name/idle_timeout_ms > /dev/null; done &
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Herbert Xu [Thu, 21 Nov 2013 19:10:04 +0000 (11:10 -0800)]
gso: handle new frag_list of frags GRO packets
Recently GRO started generating packets with frag_lists of frags.
This was not handled by GSO, thus leading to a crash.
Thankfully these packets are of a regular form and are easy to
handle. This patch handles them in two ways. For completely
non-linear frag_list entries, we simply continue to iterate over
the frag_list frags once we exhaust the normal frags. For frag_list
entries with linear parts, we call pskb_trim on the first part
of the frag_list skb, and then process the rest of the frags in
the usual way.
This patch also kills a chunk of dead frag_list code that has
obviously never ever been run since it ends up generating a bogus
GSO-segmented packet with a frag_list entry.
Future work is planned to split super big packets into TSO
ones.
Fixes: 8a29111c7ca6 ("net: gro: allow to build full sized skb") Reported-by: Christoph Paasch <christoph.paasch@uclouvain.be> Reported-by: Jerry Chu <hkchu@google.com> Reported-by: Sander Eikelenboom <linux@eikelenboom.it> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Eric Dumazet <edumazet@google.com> Tested-by: Sander Eikelenboom <linux@eikelenboom.it> Tested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
In the case that atomic_open calls finish_no_open() with
the dentry that was supplied to gfs2_atomic_open() an
extra reference count is required. This patch fixes that
issue preventing a bug trap triggering at umount time.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Johannes Berg [Thu, 21 Nov 2013 17:20:28 +0000 (18:20 +0100)]
genetlink: fix genl_set_err() group ID
Fix another really stupid bug - I introduced genl_set_err()
precisely to be able to adjust the group and reject invalid
ones, but then forgot to do so.
Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Johannes Berg [Thu, 21 Nov 2013 17:17:04 +0000 (18:17 +0100)]
genetlink: fix genlmsg_multicast() bug
Unfortunately, I introduced a tremendously stupid bug into
genlmsg_multicast() when doing all those multicast group
changes: it adjusts the group number, but then passes it
to genlmsg_multicast_netns() which does that again.
Somehow, my tests failed to catch this, so add a warning
into genlmsg_multicast_netns() and remove the offending
group ID adjustment.
Also add a warning to the similar code in other functions
so people who misuse them are more loudly warned.
Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann [Thu, 21 Nov 2013 15:50:58 +0000 (16:50 +0100)]
packet: fix use after free race in send path when dev is released
Salam reported a use after free bug in PF_PACKET that occurs when
we're sending out frames on a socket bound device and suddenly the
net device is being unregistered. It appears that commit 827d9780
introduced a possible race condition between {t,}packet_snd() and
packet_notifier(). In the case of a bound socket, packet_notifier()
can drop the last reference to the net_device and {t,}packet_snd()
might end up suddenly sending a packet over a freed net_device.
To avoid reverting 827d9780 and thus introducing a performance
regression compared to the current state of things, we decided to
hold a cached RCU protected pointer to the net device and maintain
it on write side via bind spin_lock protected register_prot_hook()
and __unregister_prot_hook() calls.
In {t,}packet_snd() path, we access this pointer under rcu_read_lock
through packet_cached_dev_get() that holds reference to the device
to prevent it from being freed through packet_notifier() while
we're in send path. This is okay to do as dev_put()/dev_hold() are
per-cpu counters, so this should not be a performance issue. Also,
the code simplifies a bit as we don't need need_rls_dev anymore.
Fixes: 827d978037d7 ("af-packet: Use existing netdev reference for bound sockets.") Reported-by: Salam Noureddine <noureddine@aristanetworks.com> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Salam Noureddine <noureddine@aristanetworks.com> Cc: Ben Greear <greearb@candelatech.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
David Vrabel [Thu, 21 Nov 2013 15:26:09 +0000 (15:26 +0000)]
xen-netback: stop the VIF thread before unbinding IRQs
If the VIF thread is still running after unbinding the Tx and Rx IRQs
in xenvif_disconnect(), the thread may attempt to raise an event which
will BUG (as the irq is unbound).
Signed-off-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Michael Opdenacker <michael.opdenacker@free-electrons.com> Acked-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
David Herrmann [Thu, 21 Nov 2013 10:50:50 +0000 (20:50 +1000)]
drm/sysfs: fix hotplug regression since lifetime changes
airlied:
The lifetime changes introduced in 5bdebb183c9702a8c57a01dff09337be3de337a6
tried to use device_create, however that led to the regression where dev->type
wasn't getting set correctly. First attempt at fixing it would have led to
a race, so this undoes the device_createa work and does it all manually
making sure the dev->type is setup before we register the device.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
projects / karo-tx-linux.git / log