Before we are able to define all subsystem ids at compile time we need
a more fine grained control what gets defined when we include
cgroup_subsys.h. For example we define the enums for the subsystems or
to declare for struct cgroup_subsys (builtin subsystem) by including
cgroup_subsys.h and defining SUBSYS accordingly.
Currently, the decision if a subsys is used is defined inside the
header by testing if CONFIG_*=y is true. By moving this test outside
of cgroup_subsys.h we are able to control it on the include level.
This is done by introducing IS_SUBSYS_ENABLED which then is defined
according the task, e.g. is CONFIG_*=y or CONFIG_*=m.
Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Cc: Gao feng <gaofeng@cn.fujitsu.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: John Fastabend <john.r.fastabend@intel.com>
Cc: netdev@vger.kernel.org
Cc: cgroups@vger.kernel.org
CGROUP_BUILTIN_SUBSYS_COUNT is used as start index or stop index when
looping over the subsys array looking either at the builtin or the
module subsystems. Since all the builtin subsystems have an id which
is lower then CGROUP_BUILTIN_SUBSYS_COUNT we know that any module will
have an id larger than CGROUP_BUILTIN_SUBSYS_COUNT. In short the ids
are sorted.
We are about to change id assignment to happen only at compile time
later in this series. That means we can't rely on the above trick
since all ids will always be defined at compile time. Furthermore,
ordering the builtin subsystems and the module subsystems is not
really necessary.
So we need a different way to know which subsystem is a builtin or a
module one. We can use the subsys[]->module pointer for this. Any
place where we need to know if a subsys is module we just check for
the pointer. If it is NULL then the subsystem is a builtin one.
With this we are able to drop the CGROUP_BUILTIN_SUBSYS_COUNT
enum. Though we need to introduce a temporary placeholder so that we
don't get a compilation error when only CONFIG_CGROUP is selected and
no single controller. An empty enum definition is not valid. Later in
this series we are able to remove the placeholder again.
And with this change we get a fix for this:
kernel/cgroup.c: In function ‘cgroup_load_subsys’:
kernel/cgroup.c:4326:38: warning: array subscript is below array bounds [-Warray-bounds]
when CONFIG_CGROUP=y and no built in controller was enabled.
Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Cc: Gao feng <gaofeng@cn.fujitsu.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: John Fastabend <john.r.fastabend@intel.com>
Cc: netdev@vger.kernel.org
Cc: cgroups@vger.kernel.org
task_netprioidx() should not be defined in case the configuration is
CONFIG_NETPRIO_CGROUP=n. The reason is that in a following patch the
net_prio_subsys_id will only be defined if CONFIG_NETPRIO_CGROUP!=n.
When net_prio is not built at all any callee should only get an empty
task_netprioidx() without any references to net_prio_subsys_id.
Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Cc: Gao feng <gaofeng@cn.fujitsu.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: John Fastabend <john.r.fastabend@intel.com>
Cc: netdev@vger.kernel.org
Cc: cgroups@vger.kernel.org
task_cls_classid() should not be defined in case the configuration is
CONFIG_NET_CLS_CGROUP=n. The reason is that in a following patch the
net_cls_subsys_id will only be defined if CONFIG_NET_CLS_CGROUP!=n.
When net_cls is not built at all a callee should only get an empty
task_cls_classid() without any references to net_cls_subsys_id.
Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Cc: Gao feng <gaofeng@cn.fujitsu.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: John Fastabend <john.r.fastabend@intel.com>
Cc: netdev@vger.kernel.org
Cc: cgroups@vger.kernel.org
The only user of sock_update_classid() is net/socket.c which happens
to include cls_cgroup.h directly.
tj: Fix build breakage due to missing cls_cgroup.h inclusion in
drivers/net/tun.c reported in linux-next by Stephen.
Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Gao feng <gaofeng@cn.fujitsu.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: John Fastabend <john.r.fastabend@intel.com>
Cc: netdev@vger.kernel.org
Cc: cgroups@vger.kernel.org
While reading through Documentation/cgroups/cgroups.txt, I found a
number of minor wordos and typos. The patch below is a conservative
handling of some of these: it provides just a number of "obviously
correct" fixes to the English that improve the readability
of the document somewhat. Obviously some more significant
fixes could be made to the document, but some of those
may not be in the "obviously correct" category.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
new_xattr in __simple_xattr_set() is only initialized with a valid
pointer if value is not NULL, which only happens if this function is
called directly with the intention to remove an existing extended
attribute. Even being safe to be this way, smatch warns about possible
NULL dereference. Dan Carpenter suggested using uninitialized_var()
which will make both gcc and smatch happy.
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Aristeu Rozanski <aris@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
v2: add function documentation instead of adding a separate file under
Documentation/
tj: Updated comment a bit and rolled in Randy's suggestions.
Cc: Li Zefan <lizefan@huawei.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Lennart Poettering <lpoetter@redhat.com>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Aristeu Rozanski <aris@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This is one of the items in the plumber's wish list.
For use cases:
>> What would the use case be for this?
>
> Attaching meta information to services, in an easily discoverable
> way. For example, in systemd we create one cgroup for each service, and
> could then store data like the main pid of the specific service as an
> xattr on the cgroup itself. That way we'd have almost all service state
> in the cgroupfs, which would make it possible to terminate systemd and
> later restart it without losing any state information. But there's more:
> for example, some very peculiar services cannot be terminated on
> shutdown (i.e. fakeraid DM stuff) and it would be really nice if the
> services in question could just mark that on their cgroup, by setting an
> xattr. On the more desktopy side of things there are other
> possibilities: for example there are plans defining what an application
> is along the lines of a cgroup (i.e. an app being a collection of
> processes). With xattrs one could then attach an icon or human readable
> program name on the cgroup.
>
> The key idea is that this would allow attaching runtime meta information
> to cgroups and everything they model (services, apps, vms), that doesn't
> need any complex userspace infrastructure, has good access control
> (i.e. because the file system enforces that anyway, and there's the
> "trusted." xattr namespace), notifications (inotify), and can easily be
> shared among applications.
>
> Lennart
v7:
- no changes
v6:
- remove user xattr namespace, only allow trusted and security
v5:
- check for capabilities before setting/removing xattrs
v4:
- no changes
v3:
- instead of config option, use mount option to enable xattr support
Original-patch-by: Li Zefan <lizefan@huawei.com>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Lennart Poettering <lpoetter@redhat.com>
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Aristeu Rozanski <aris@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
When remounting cgroupfs with some subsystems added to it and some
removed, cgroup will remove all the files in root directory and then
re-popluate it.
What I'm doing here is, only remove files which belong to subsystems that
are to be unbinded, and only create files for newly-added subsystems.
The purpose is to have all other files untouched.
This is a preparation for cgroup xattr support.
v7:
- checkpatch warnings fixed
v6:
- no changes
v5:
- no changes
v4:
- refactored cgroup_clear_directory() to not use cgroup_rm_file()
- instead of going thru the list of files, get the file list using the
subsystems
- use 'subsys_mask' instead of {added,removed}_bits and made
cgroup_populate_dir() to match the parameters with cgroup_clear_directory()
v3:
- refresh patches after recent refactoring
Original-patch-by: Li Zefan <lizefan@huawei.com>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Lennart Poettering <lpoetter@redhat.com>
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Aristeu Rozanski <aris@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Extract in-memory xattr APIs from tmpfs. Will be used by cgroup.
$ size vmlinux.o
text data bss dec hex filename
4658782 880729 5195032 10734543 a3cbcf vmlinux.o
$ size vmlinux.o
text data bss dec hex filename
4658957 880729 5195032 10734718 a3cc7e vmlinux.o
v7:
- checkpatch warnings fixed
- Implement the changes requested by Hugh Dickins:
- make simple_xattrs_init and simple_xattrs_free inline
- get rid of locking and list reinitialization in simple_xattrs_free,
they're not needed
v6:
- no changes
v5:
- no changes
v4:
- move simple_xattrs_free() to fs/xattr.c
v3:
- in kmem_xattrs_free(), reinitialize the list
- use simple_xattr_* prefix
- introduce simple_xattr_add() to prevent direct list usage
Original-patch-by: Li Zefan <lizefan@huawei.com>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Lennart Poettering <lpoetter@redhat.com>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Aristeu Rozanski <aris@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Pull drm fixes from Dave Airlie:
"Intel: edid fixes, power consumption fix, s/r fix, haswell fix
Radeon: BIOS loading fixes for UEFI and Thunderbolt machines, better
MSAA validation, lockup timeout fixes, modesetting fixes
One udl dpms fix, one vmwgfx fix, a couple of trivial core changes.
There is an export added to ACPI as part of the radeon bios fixes.
I've also included the fbcon flashing cursor vs deinit race fix, that
seems the simplest place to start"
Trivial conflict in drivers/video/console/fbcon.c due to me having
already applied the fbcon flashing cursor vs deinit race fix, and Dave
had added a comment in there too.
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (22 commits)
fbcon: fix race condition between console lock and cursor timer (v1.1)
drm: Add missing static storage class specifiers in drm_proc.c file
drm/udl: dpms off the crtc when disabled.
drm: Remove two unused fields from struct drm_display_mode
drm: stop vmgfx driver explosion
drm/radeon/ss: use num_crtc rather than hardcoded 6
Revert "drm/radeon: fix bo creation retry path"
drm/i915: use hsw rps tuning values everywhere on gen6+
drm/radeon: split ATRM support out from the ATPX handler (v3)
drm/radeon: convert radeon vfct code to use acpi_get_table_with_size
ACPI: export symbol acpi_get_table_with_size
drm/radeon: implement ACPI VFCT vbios fetch (v3)
drm/radeon/kms: extend the Fujitsu D3003-S2 board connector quirk to cover later silicon stepping
drm/radeon: fix checking of MSAA renderbuffers on r600-r700
drm/radeon: allow CMASK and FMASK in the CS checker on r600-r700
drm/radeon: init lockup timeout on ring init
drm/radeon: avoid turning off spread spectrum for used pll
drm/i915: fall back to bit-banging if GMBUS fails in CRT EDID reads
drm/i915: extract connector update from intel_ddc_get_modes() for reuse
drm/i915: fix hsw uncached pte
...
Pull SCSI target fixes from Nicholas Bellinger:
"The executive summary includes:
- Post-merge review comments for tcm_vhost (MST + nab)
- Avoid debugging overhead when not debugging for tcm-fc(FCoE) (MDR)
- Fix NULL pointer dereference bug on alloc_page failulre (Yi Zou)
- Fix REPORT_LUNs regression bug with pSCSI export (AlexE + nab)
- Fix regression bug with handling of zero-length data CDBs (nab)
- Fix vhost_scsi_target structure alignment (MST)
Thanks again to everyone who contributed a bugfix patch, gave review
feedback on tcm_vhost code, and/or reported a bug during their own
testing over the last weeks.
There is one other outstanding bug reported by Roland recently related
to SCSI transfer length overflow handling, for which the current
proposed bugfix has been left in queue pending further testing with
other non iscsi-target based fabric drivers.
As the patch is verified with loopback (local SGL memory from SCSI
LLD) + tcm_qla2xxx (TCM allocated SGL memory mapped to PCI HW) fabric
ports, it will be included into the next 3.6-rc-fixes PULL request."
* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
target: Remove unused se_cmd.cmd_spdtl
tcm_fc: rcu_deref outside rcu lock/unlock section
tcm_vhost: Fix vhost_scsi_target structure alignment
target: Fix regression bug with handling of zero-length data CDBs
target/pscsi: Fix bug with REPORT_LUNs handling for SCSI passthrough
tcm_vhost: Change vhost_scsi_target->vhost_wwpn to char *
target: fix NULL pointer dereference bug alloc_page() fails to get memory
tcm_fc: Avoid debug overhead when not debugging
tcm_vhost: Post-merge review changes requested by MST
tcm_vhost: Fix incorrect IS_ERR() usage in vhost_scsi_map_iov_to_sgl
Pull i2c-embedded fixes from Wolfram Sang:
"Some bugfixes for the "embedded" part of the I2C subsystem. The fixes
affect mostly drivers which have been largely reworked lately and
where regressions appeared."
* 'i2c-embedded/for-current' of git://git.pengutronix.de/git/wsa/linux:
i2c: tegra: protect suspend/resume callbacks with CONFIG_PM_SLEEP
i2c: diolan-u2c: Fix master_xfer return code
I2C: OMAP: xfer: fix runtime PM get/put balance on error
i2c: nomadik: Add default configuration into the Nomadik I2C driver
These patches fix the Samsung PWM driver and perform some minor cleanups
like fixing checkpatch and sparse warnings. Two redundant error messages
are removed and the Kconfig help text for the PWM subsystem is made more
descriptive.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.19 (GNU/Linux)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=oTl5
-----END PGP SIGNATURE-----
Merge tag 'for-3.6-rc3' of git://gitorious.org/linux-pwm/linux-pwm
Pull pwm fixes from Thierry Reding:
"These patches fix the Samsung PWM driver and perform some minor
cleanups like fixing checkpatch and sparse warnings.
Two redundant error messages are removed and the Kconfig help text for
the PWM subsystem is made more descriptive."
* tag 'for-3.6-rc3' of git://gitorious.org/linux-pwm/linux-pwm:
pwm: Improve Kconfig help text
pwm: core: Fix coding style issues
pwm: vt8500: Fix coding style issue
pwm: Remove a redundant error message when devm_request_and_ioremap fails
pwm: samsung: add missing device pointer to struct pwm_chip
pwm: Add missing static storage class specifiers in core.c file
Pull ceph fixes from Sage Weil:
"Jim's fix closes a narrow race introduced with the msgr changes. One
fix resolves problems with debugfs initialization that Yan found when
multiple client instances are created (e.g., two clusters mounted, or
rbd + cephfs), another one fixes problems with mounting a nonexistent
server subdirectory, and the last one fixes a divide by zero error
from unsanitized ioctl input that Dan Carpenter found."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
ceph: avoid divide by zero in __validate_layout()
libceph: avoid truncation due to racing banners
ceph: tolerate (and warn on) extraneous dentry from mds
libceph: delay debugfs initialization until we learn global_id
- NFSv3 mounts need to fail if the FSINFO rpc call fails
- Ensure that the NFS commit cache gets torn down when we unload the
NFS module.
- Fix memory scribble issues when interrupting a LAYOUTGET rpc call
- Fix NFSv4 legacy idmapper regressions
- Fix issues with the NFSv4 getacl command
- Fix a regression when using the legacy "mount -t nfs4"
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.12 (GNU/Linux)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=lqfh
-----END PGP SIGNATURE-----
Merge tag 'nfs-for-3.6-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client bugfixes from Trond Myklebust:
- NFSv3 mounts need to fail if the FSINFO rpc call fails
- Ensure that the NFS commit cache gets torn down when we unload the
NFS module.
- Fix memory scribble issues when interrupting a LAYOUTGET rpc call
- Fix NFSv4 legacy idmapper regressions
- Fix issues with the NFSv4 getacl command
- Fix a regression when using the legacy "mount -t nfs4"
* tag 'nfs-for-3.6-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
NFSv3: Ensure that do_proc_get_root() reports errors correctly
NFSv4: Ensure that nfs4_alloc_client cleans up on error.
NFS: return -ENOKEY when the upcall fails to map the name
NFS: Clear key construction data if the idmap upcall fails
NFSv4: Don't use private xdr_stream fields in decode_getacl
NFSv4: Fix the acl cache size calculation
NFSv4: Fix pointer arithmetic in decode_getacl
NFS: Alias the nfs module to nfs4
NFS: Fix a regression when loading the NFS v4 module
NFSv4.1: Remove a bogus BUG_ON() in nfs4_layoutreturn_done
pnfs-obj: Better IO pattern in case of unaligned offset
NFS41: add pg_layout_private to nfs_pageio_descriptor
pnfs: nfs4_proc_layoutget returns void
pnfs: defer release of pages in layoutget
nfs: tear down caches in nfs_init_writepagecache when allocation fails
Pull assorted fixes - mostly vfs - from Al Viro:
"Assorted fixes, with an unexpected detour into vfio refcounting logics
(fell out when digging in an analog of eventpoll race in there)."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
task_work: add a scheduling point in task_work_run()
fs: fix fs/namei.c kernel-doc warnings
eventpoll: use-after-possible-free in epoll_create1()
vfio: grab vfio_device reference *before* exposing the sucker via fd_install()
vfio: get rid of vfio_device_put()/vfio_group_get_device* races
vfio: get rid of open-coding kref_put_mutex
introduce kref_put_mutex()
vfio: don't dereference after kfree...
mqueue: lift mnt_want_write() outside ->i_mutex, clean up a bit
It seems commit 4a9d4b02 (switch fput to task_work_add) reintroduced
the problem addressed in commit 944be0b2 (close_files(): add scheduling
point)
If a server process with a lot of files (say 2 million tcp sockets)
is killed, we can spend a lot of time in task_work_run() and trigger
a soft lockup.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Fix kernel-doc warnings in fs/namei.c:
Warning(fs/namei.c:360): No description found for parameter 'inode'
Warning(fs/namei.c:672): No description found for parameter 'nd'
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
As soon as we'd installed the file into descriptor table, it can
get closed by another thread. Freeing ep in process...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
It's not critical (anymore) since another thread closing the file will block
on ->device_lock before it gets to dropping the final reference, but it's
definitely cleaner that way...
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
we really need to make sure that dropping the last reference happens
under the group->device_lock; otherwise a loop (under device_lock)
might find vfio_device instance that is being freed right now, has
already dropped the last reference and waits on device_lock to exclude
the sucker from the list.
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
So we've had a fair few reports of fbcon handover breakage between
efi/vesafb and i915 surface recently, so I dedicated a couple of
days to finding the problem.
Essentially the last thing we saw was the conflicting framebuffer
message and that was all.
So after much tracing with direct netconsole writes (printks
under console_lock not so useful), I think I found the race.
Thread A (driver load) Thread B (timer thread)
unbind_con_driver -> |
bind_con_driver -> |
vc->vc_sw->con_deinit -> |
fbcon_deinit -> |
console_lock() |
| |
| fbcon_flashcursor timer fires
| console_lock() <- blocked for A
|
|
fbcon_del_cursor_timer ->
del_timer_sync
(BOOM)
Of course because all of this is under the console lock,
we never see anything, also since we also just unbound the active
console guess what we never see anything.
Hopefully this fixes the problem for anyone seeing vesafb->kms
driver handoff.
v1.1: add comment suggestion from Alan.
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
Merge fixes from Andrew Morton.
Random drivers and some VM fixes.
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (17 commits)
mm: compaction: Abort async compaction if locks are contended or taking too long
mm: have order > 0 compaction start near a pageblock with free pages
rapidio/tsi721: fix unused variable compiler warning
rapidio/tsi721: fix inbound doorbell interrupt handling
drivers/rtc/rtc-rs5c348.c: fix hour decoding in 12-hour mode
mm: correct page->pfmemalloc to fix deactivate_slab regression
drivers/rtc/rtc-pcf2123.c: initialize dynamic sysfs attributes
mm/compaction.c: fix deferring compaction mistake
drivers/misc/sgi-xp/xpc_uv.c: SGI XPC fails to load when cpu 0 is out of IRQ resources
string: do not export memweight() to userspace
hugetlb: update hugetlbpage.txt
checkpatch: add control statement test to SINGLE_STATEMENT_DO_WHILE_MACRO
mm: hugetlbfs: correctly populate shared pmd
cciss: fix incorrect scsi status reporting
Documentation: update mount option in filesystem/vfat.txt
mm: change nr_ptes BUG_ON to WARN_ON
cs5535-clockevt: typo, it's MFGPT, not MFPGT
Pull media fixes from Mauro Carvalho Chehab:
"For bug fixes, at soc_camera, si470x, uvcvideo, iguanaworks IR driver,
radio_shark Kbuild fixes, and at the V4L2 core (radio fixes)."
* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
[media] media: soc_camera: don't clear pix->sizeimage in JPEG mode
[media] media: mx2_camera: Fix clock handling for i.MX27
[media] video: mx2_camera: Use clk_prepare_enable/clk_disable_unprepare
[media] video: mx1_camera: Use clk_prepare_enable/clk_disable_unprepare
[media] media: mx3_camera: buf_init() add buffer state check
[media] radio-shark2: Only compile led support when CONFIG_LED_CLASS is set
[media] radio-shark: Only compile led support when CONFIG_LED_CLASS is set
[media] radio-shark*: Call cancel_work_sync from disconnect rather then release
[media] radio-shark*: Remove work-around for dangling pointer in usb intfdata
[media] Add USB dependency for IguanaWorks USB IR Transceiver
[media] Add missing logging for rangelow/high of hwseek
[media] VIDIOC_ENUM_FREQ_BANDS fix
[media] mem2mem_testdev: fix querycap regression
[media] si470x: v4l2-compliance fixes
[media] DocBook: Remove a spurious character
[media] uvcvideo: Reset the bytesused field when recycling an erroneous buffer
Pull networking update from David Miller:
"A couple weeks of bug fixing in there. The largest chunk is all the
broken crap Amerigo Wang found in the netpoll layer."
1) netpoll and it's users has several serious bugs:
a) uses GFP_KERNEL with locks held
b) interfaces requiring interrupts disabled are called with them
enabled
c) and vice versa
d) VLAN tag demuxing, as per all other RX packet input paths, is not
applied
All from Amerigo Wang.
2) Hopefully cure the ipv4 mapped ipv6 address TCP early demux bugs for
good, from Neal Cardwell.
3) Unlike AF_UNIX, AF_PACKET sockets don't set a default credentials
when the user doesn't specify one explicitly during sendmsg().
Instead we attach an empty (zero) SCM credential block which is
definitely not what we want. Fix from Eric Dumazet.
4) IPv6 illegally invokes netdevice notifiers with RCU lock held, fix
from Ben Hutchings.
5) inet_csk_route_child_sock() checks wrong inet options pointer, fix
from Christoph Paasch.
6) When AF_PACKET is used for transmit, packet loopback doesn't behave
properly when a socket fanout is enabled, from Eric Leblond.
7) On bluetooth l2cap channel create failure, we leak the socket, from
Jaganath Kanakkassery.
8) Fix all the netprio file handling bugs found by Al Viro, from John
Fastabend.
9) Several error return and NULL deref bug fixes in networking drivers
from Julia Lawall.
10) A large smattering of struct padding et al. kernel memory leaks to
userspace found of Mathias Krause.
11) Conntrack expections in netfilter can access an uninitialized timer,
fix from Pablo Neira Ayuso.
12) Several netfilter SIP tracker bug fixes from Patrick McHardy.
13) IPSEC ipv6 routes are not initialized correctly all the time,
resulting in an OOPS in inet_putpeer(). Also from Patrick McHardy.
14) Bridging does rcu_dereference() outside of RCU protected area, from
Stephen Hemminger.
15) Fix routing cache removal performance regression when looking up
output routes that have a local destination. From Zheng Yan.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (87 commits)
af_netlink: force credentials passing [CVE-2012-3520]
ipv4: fix ip header ident selection in __ip_make_skb()
ipv4: Use newinet->inet_opt in inet_csk_route_child_sock()
tcp: fix possible socket refcount problem
net: tcp: move sk_rx_dst_set call after tcp_create_openreq_child()
net/core/dev.c: fix kernel-doc warning
netconsole: remove a redundant netconsole_target_put()
net: ipv6: fix oops in inet_putpeer()
net/stmmac: fix issue of clk_get for Loongson1B.
caif: Do not dereference NULL in chnl_recv_cb()
af_packet: don't emit packet on orig fanout group
drivers/net/irda: fix error return code
drivers/net/wan/dscc4.c: fix error return code
drivers/net/wimax/i2400m/fw.c: fix error return code
smsc75xx: add missing entry to MAINTAINERS
net: qmi_wwan: new devices: UML290 and K5006-Z
net: sh_eth: Add eth support for R8A7779 device
netdev/phy: skip disabled mdio-mux nodes
dt: introduce for_each_available_child_of_node, of_get_next_available_child
net: netprio: fix cgrp create and write priomap race
...
Jim Schutt reported a problem that pointed at compaction contending
heavily on locks. The workload is straight-forward and in his own words;
The systems in question have 24 SAS drives spread across 3 HBAs,
running 24 Ceph OSD instances, one per drive. FWIW these servers
are dual-socket Intel 5675 Xeons w/48 GB memory. I've got ~160
Ceph Linux clients doing dd simultaneously to a Ceph file system
backed by 12 of these servers.
Early in the test everything looks fine
procs -------------------memory------------------ ---swap-- -----io---- --system-- -----cpu-------
r b swpd free buff cache si so bi bo in cs us sy id wa st
31 15 0 287216 576 38606628 0 0 2 1158 2 14 1 3 95 0 0
27 15 0 225288 576 38583384 0 0 18 2222016 203357 134876 11 56 17 15 0
28 17 0 219256 576 38544736 0 0 11 2305932 203141 146296 11 49 23 17 0
6 18 0 215596 576 38552872 0 0 7 2363207 215264 166502 12 45 22 20 0
22 18 0 226984 576 38596404 0 0 3 2445741 223114 179527 12 43 23 22 0
and then it goes to pot
procs -------------------memory------------------ ---swap-- -----io---- --system-- -----cpu-------
r b swpd free buff cache si so bi bo in cs us sy id wa st
163 8 0 464308 576 36791368 0 0 11 22210 866 536 3 13 79 4 0
207 14 0 917752 576 36181928 0 0 712 1345376 134598 47367 7 90 1 2 0
123 12 0 685516 576 36296148 0 0 429 1386615 158494 60077 8 84 5 3 0
123 12 0 598572 576 36333728 0 0 1107 1233281 147542 62351 7 84 5 4 0
622 7 0 660768 576 36118264 0 0 557 1345548 151394 59353 7 85 4 3 0
223 11 0 283960 576 36463868 0 0 46 1107160 121846 33006 6 93 1 1 0
Note that system CPU usage is very high blocks being written out has
dropped by 42%. He analysed this with perf and found
perf record -g -a sleep 10
perf report --sort symbol --call-graph fractal,5
34.63% [k] _raw_spin_lock_irqsave
|
|--97.30%-- isolate_freepages
| compaction_alloc
| unmap_and_move
| migrate_pages
| compact_zone
| compact_zone_order
| try_to_compact_pages
| __alloc_pages_direct_compact
| __alloc_pages_slowpath
| __alloc_pages_nodemask
| alloc_pages_vma
| do_huge_pmd_anonymous_page
| handle_mm_fault
| do_page_fault
| page_fault
| |
| |--87.39%-- skb_copy_datagram_iovec
| | tcp_recvmsg
| | inet_recvmsg
| | sock_recvmsg
| | sys_recvfrom
| | system_call
| | __recv
| | |
| | --100.00%-- (nil)
| |
| --12.61%-- memcpy
--2.70%-- [...]
There was other data but primarily it is all showing that compaction is
contended heavily on the zone->lock and zone->lru_lock.
commit [b2eef8c0: mm: compaction: minimise the time IRQs are disabled
while isolating pages for migration] noted that it was possible for
migration to hold the lru_lock for an excessive amount of time. Very
broadly speaking this patch expands the concept.
This patch introduces compact_checklock_irqsave() to check if a lock
is contended or the process needs to be scheduled. If either condition
is true then async compaction is aborted and the caller is informed.
The page allocator will fail a THP allocation if compaction failed due
to contention. This patch also introduces compact_trylock_irqsave()
which will acquire the lock only if it is not contended and the process
does not need to schedule.
Reported-by: Jim Schutt <jaschut@sandia.gov>
Tested-by: Jim Schutt <jaschut@sandia.gov>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 7db8889ab0 ("mm: have order > 0 compaction start off where it
left") introduced a caching mechanism to reduce the amount work the free
page scanner does in compaction. However, it has a problem. Consider
two process simultaneously scanning free pages
C
Process A M S F
|---------------------------------------|
Process B M FS
C is zone->compact_cached_free_pfn
S is cc->start_pfree_pfn
M is cc->migrate_pfn
F is cc->free_pfn
In this diagram, Process A has just reached its migrate scanner, wrapped
around and updated compact_cached_free_pfn accordingly.
Simultaneously, Process B finishes isolating in a block and updates
compact_cached_free_pfn again to the location of its free scanner.
Process A moves to "end_of_zone - one_pageblock" and runs this check
if (cc->order > 0 && (!cc->wrapped ||
zone->compact_cached_free_pfn >
cc->start_free_pfn))
pfn = min(pfn, zone->compact_cached_free_pfn);
compact_cached_free_pfn is above where it started so the free scanner
skips almost the entire space it should have scanned. When there are
multiple processes compacting it can end in a situation where the entire
zone is not being scanned at all. Further, it is possible for two
processes to ping-pong update to compact_cached_free_pfn which is just
random.
Overall, the end result wrecks allocation success rates.
There is not an obvious way around this problem without introducing new
locking and state so this patch takes a different approach.
First, it gets rid of the skip logic because it's not clear that it
matters if two free scanners happen to be in the same block but with
racing updates it's too easy for it to skip over blocks it should not.
Second, it updates compact_cached_free_pfn in a more limited set of
circumstances.
If a scanner has wrapped, it updates compact_cached_free_pfn to the end
of the zone. When a wrapped scanner isolates a page, it updates
compact_cached_free_pfn to point to the highest pageblock it
can isolate pages from.
If a scanner has not wrapped when it has finished isolated pages it
checks if compact_cached_free_pfn is pointing to the end of the
zone. If so, the value is updated to point to the highest
pageblock that pages were isolated from. This value will not
be updated again until a free page scanner wraps and resets
compact_cached_free_pfn.
This is not optimal and it can still race but the compact_cached_free_pfn
will be pointing to or very near a pageblock with free pages.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix unused variable compiler warning when built with CONFIG_RAPIDIO_DEBUG
option off.
This patch is applicable to kernel versions starting from v3.2
Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make sure that there is no doorbell messages left behind due to disabled
interrupts during inbound doorbell processing.
The most common case for this bug is loss of rionet JOIN messages in
systems with three or more rionet participants and MSI or MSI-X enabled.
As result, requests for packet transfers may finish with "destination
unreachable" error message.
This patch is applicable to kernel versions starting from v3.2.
Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Correct the offset by subtracting 20 from tm_hour before taking the
modulo 12.
[ "Why 20?" I hear you ask. Or at least I did.
Here's the reason why: RS5C348_BIT_PM is 32, and is - stupidly -
included in the RS5C348_HOURS_MASK define. So it's really subtracting
out that bit to get "hour+12". But then because it does things modulo
12, it needs to add the 12 in again afterwards anyway.
This code is confused. It would be much clearer if RS5C348_HOURS_MASK
just didn't include the RS5C348_BIT_PM bit at all, then it wouldn't
need to do the silly subtract either.
Whatever. It's all just math, the end result is the same. - Linus ]
Reported-by: James Nute <newten82@gmail.com>
Tested-by: James Nute <newten82@gmail.com>
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit cfd19c5a9e ("mm: only set page->pfmemalloc when
ALLOC_NO_WATERMARKS was used") tried to narrow down page->pfmemalloc
setting, but it missed some places the pfmemalloc should be set.
So, in __slab_alloc, the unalignment pfmemalloc and ALLOC_NO_WATERMARKS
cause incorrect deactivate_slab() on our core2 server:
64.73% fio [kernel.kallsyms] [k] _raw_spin_lock
|
--- _raw_spin_lock
|
|---0.34%-- deactivate_slab
| __slab_alloc
| kmem_cache_alloc
| |
That causes our fio sync write performance to have a 40% regression.
Move the checking in get_page_from_freelist() which resolves this issue.
Signed-off-by: Alex Shi <alex.shi@intel.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: David Miller <davem@davemloft.net
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Eric Dumazet <eric.dumazet@gmail.com>
Tested-by: Sage Weil <sage@inktank.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dynamically allocated sysfs attributes must be initialized using
sysfs_attr_init(), otherwise lockdep complains: BUG: key <address> not in
.data!
Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Ilya Shchepetkov <shchepetkov@ispras.ru>
Cc: Chris Verges <chrisv@cyberswitching.com>
Cc: Christian Pellegrin <chripell@fsfe.org>
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>
Commit aff622495c ("vmscan: only defer compaction for failed order and
higher") fixed bad deferring policy but made mistake about checking
compact_order_failed in __compact_pgdat(). So it can't update
compact_order_failed with the new order. This ends up preventing
correct operation of policy deferral. This patch fixes it.
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On many of our larger systems, CPU 0 has had all of its IRQ resources
consumed before XPC loads. Worst cases on machines with multiple 10
GigE cards and multiple IB cards have depleted the entire first socket
of IRQs.
This patch makes selecting the node upon which IRQs are allocated (as
well as all the other GRU Message Queue structures) specifiable as a
module load param and has a default behavior of searching all nodes/cpus
for an available resources.
[akpm@linux-foundation.org: fix build: include cpu.h and module.h]
Signed-off-by: Robin Holt <holt@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the following warning:
usr/include/linux/string.h:8: userspace cannot reference function or variable defined in the kernel
Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Acked-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit f0f57b2b14 ("mm: move hugepage test examples to
tools/testing/selftests/vm") moved map_hugetlb.c, hugepage-shm.c and
hugepage-mmap.c tests into tools/testing/selftests/vm/ directory, but it
didn't update hugetlbpage.txt
Signed-off-by: Zhouping Liu <sanweidaying@gmail.com>
Acked-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit b13edf7ff2 ("checkpatch: add checks for do {} while (0) macro
misuses") added a test that is overly simplistic for single statement
macros.
Macros that start with control tests should be enclosed in a do {} while
(0) loop.
Add the necessary control tests to the check.
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Andy Whitcroft <apw@canonical.com>
Tested-by: Franz Schrober <franzschrober@yahoo.de>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Each page mapped in a process's address space must be correctly
accounted for in _mapcount. Normally the rules for this are
straightforward but hugetlbfs page table sharing is different. The page
table pages at the PMD level are reference counted while the mapcount
remains the same.
If this accounting is wrong, it causes bugs like this one reported by
Larry Woodman:
kernel BUG at mm/filemap.c:135!
invalid opcode: 0000 [#1] SMP
CPU 22
Modules linked in: bridge stp llc sunrpc binfmt_misc dcdbas microcode pcspkr acpi_pad acpi]
Pid: 18001, comm: mpitest Tainted: G W 3.3.0+ #4 Dell Inc. PowerEdge R620/07NDJ2
RIP: 0010:[<ffffffff8112cfed>] [<ffffffff8112cfed>] __delete_from_page_cache+0x15d/0x170
Process mpitest (pid: 18001, threadinfo ffff880428972000, task ffff880428b5cc20)
Call Trace:
delete_from_page_cache+0x40/0x80
truncate_hugepages+0x115/0x1f0
hugetlbfs_evict_inode+0x18/0x30
evict+0x9f/0x1b0
iput_final+0xe3/0x1e0
iput+0x3e/0x50
d_kill+0xf8/0x110
dput+0xe2/0x1b0
__fput+0x162/0x240
During fork(), copy_hugetlb_page_range() detects if huge_pte_alloc()
shared page tables with the check dst_pte == src_pte. The logic is if
the PMD page is the same, they must be shared. This assumes that the
sharing is between the parent and child. However, if the sharing is
with a different process entirely then this check fails as in this
diagram:
parent
|
------------>pmd
src_pte----------> data page
^
other--------->pmd--------------------|
^
child-----------|
dst_pte
For this situation to occur, it must be possible for Parent and Other to
have faulted and failed to share page tables with each other. This is
possible due to the following style of race.
PROC A PROC B
copy_hugetlb_page_range copy_hugetlb_page_range
src_pte == huge_pte_offset src_pte == huge_pte_offset
!src_pte so no sharing !src_pte so no sharing
(time passes)
hugetlb_fault hugetlb_fault
huge_pte_alloc huge_pte_alloc
huge_pmd_share huge_pmd_share
LOCK(i_mmap_mutex)
find nothing, no sharing
UNLOCK(i_mmap_mutex)
LOCK(i_mmap_mutex)
find nothing, no sharing
UNLOCK(i_mmap_mutex)
pmd_alloc pmd_alloc
LOCK(instantiation_mutex)
fault
UNLOCK(instantiation_mutex)
LOCK(instantiation_mutex)
fault
UNLOCK(instantiation_mutex)
These two processes are not poing to the same data page but are not
sharing page tables because the opportunity was missed. When either
process later forks, the src_pte == dst pte is potentially insufficient.
As the check falls through, the wrong PTE information is copied in
(harmless but wrong) and the mapcount is bumped for a page mapped by a
shared page table leading to the BUG_ON.
This patch addresses the issue by moving pmd_alloc into huge_pmd_share
which guarantees that the shared pud is populated in the same critical
section as pmd. This also means that huge_pte_offset test in
huge_pmd_share is serialized correctly now which in turn means that the
success of the sharing will be higher as the racing tasks see the pud
and pmd populated together.
Race identified and changelog written mostly by Mel Gorman.
{akpm@linux-foundation.org: attempt to make the huge_pmd_share() comment comprehensible, clean up coding style]
Reported-by: Larry Woodman <lwoodman@redhat.com>
Tested-by: Larry Woodman <lwoodman@redhat.com>
Reviewed-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Ken Chen <kenchen@google.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Delete code which sets SCSI status incorrectly as it's already been set
correctly above this incorrect code. The bug was introduced in 2009 by
commit b0e15f6db1 ("cciss: fix typo that causes scsi status to be
lost.")
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Reported-by: Roel van Meer <roel.vanmeer@bokxing.nl>
Tested-by: Roel van Meer <roel.vanmeer@bokxing.nl>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Occasionally an isolated BUG_ON(mm->nr_ptes) gets reported, indicating
that not all the page tables allocated could be found and freed when
exit_mmap() tore down the user address space.
There's usually nothing we can say about it, beyond that it's probably a
sign of some bad memory or memory corruption; though it might still
indicate a bug in vma or page table management (and did recently reveal a
race in THP, fixed a few months ago).
But one overdue change we can make is from BUG_ON to WARN_ON.
It's fairly likely that the system will crash shortly afterwards in some
other way (for example, the BUG_ON(page_mapped(page)) in
__delete_from_page_cache(), once an inode mapped into the lost page tables
gets evicted); but might tell us more before that.
Change the BUG_ON(page_mapped) to WARN_ON too? Later perhaps: I'm less
eager, since that one has several times led to fixes.
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
