init_css() takes the cgroup the new css belongs to as an argument and
initializes the new css's ->cgroup and ->parent pointers but doesn't
acquire the matching reference counts. After the previous patch,
create_css() puts init_css() and reference acquisition right next to
each other. Let's move reference acquistion into init_css() and
rename the function to init_and_link_css(). This makes sense and is
easier to follow. This makes the root csses to hold a reference on
cgrp_dfl_root.cgrp, which is harmless.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Currently, when create_css() fails in the middle, the half-initialized
css is freed by invoking cgroup_subsys->css_free() directly. This
patch updates the function so that it invokes RCU free path instead.
As the RCU free path puts the parent css and owning cgroup, their
references are now acquired right after a new css is successfully
allocated.
This doesn't make any visible difference now but is to enable
implementing css->id and RCU protected lookup by such IDs.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Currently, cgroup_root->cgroup_idr is protected by cgroup_mutex, which
ends up requiring cgroup_put() to be invoked under sleepable context.
This is okay for now but is an unusual requirement and we'll soon add
css->id which will have the same problem but won't be able to simply
grab cgroup_mutex as removal will have to happen from css_release()
which can't sleep.
Introduce cgroup_idr_lock and idr_alloc/replace/remove() wrappers
which protects the idr operations with the lock and use them for
cgroup_root->cgroup_idr. cgroup_put() no longer needs to grab
cgroup_mutex and css_from_id() is updated to always require RCU read
lock instead of either RCU read lock or cgroup_mutex, which doesn't
affect the existing users.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Currently, cgroup->id is allocated from 0, which is always assigned to
the root cgroup; unfortunately, memcg wants to use ID 0 to indicate
invalid IDs and ends up incrementing all IDs by one.
It's reasonable to reserve 0 for special purposes. This patch updates
cgroup core so that ID 0 is not used and the root cgroups get ID 1.
The ID incrementing is removed form memcg.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Li Zefan <lizefan@huawei.com>
There's no reason to use atomic bitops for cgroup_subsys_state->flags,
cgroup_root->flags and various subsys_masks. This patch updates those
to use bitwise and/or operations instead and converts them form
unsigned long to unsigned int.
This makes the fields occupy (marginally) smaller space and makes it
clear that they don't require atomicity.
This patch doesn't cause any behavior difference.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Use pr_fmt and remove embedded prefixes.
Realign modified multi-line statements to open parenthesis.
Convert embedded function name to "%s: ", __func__
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
As suggested by scripts/checkpatch.pl, substitude all pr_warning()
with pr_warn().
No functional change.
Signed-off-by: Jianyu Zhan <nasa4836@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
6612f05b88 ("cgroup: unify pidlist and other file handling")
has removed the only user of cgroup_pidlist_seq_operations :
cgroup_pidlist_open().
This patch removes it.
Signed-off-by: Jianyu Zhan <nasa4836@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
1d5be6b287 ("cgroup: move module ref handling into
rebind_subsystems()") makes parse_cgroupfs_options() no longer takes
refcounts on subsystems.
And unified hierachy makes parse_cgroupfs_options not need to call
with cgroup_mutex held to protect the cgroup_subsys[].
So this patch removes BUG_ON() and the comment. As the comment
doesn't contain useful information afterwards, the whole comment is
removed.
Signed-off-by: Jianyu Zhan <nasa4836@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
cgroup users often need a way to determine when a cgroup's
subhierarchy becomes empty so that it can be cleaned up. cgroup
currently provides release_agent for it; unfortunately, this mechanism
is riddled with issues.
* It delivers events by forking and execing a userland binary
specified as the release_agent. This is a long deprecated method of
notification delivery. It's extremely heavy, slow and cumbersome to
integrate with larger infrastructure.
* There is single monitoring point at the root. There's no way to
delegate management of a subtree.
* The event isn't recursive. It triggers when a cgroup doesn't have
any tasks or child cgroups. Events for internal nodes trigger only
after all children are removed. This again makes it impossible to
delegate management of a subtree.
* Events are filtered from the kernel side. "notify_on_release" file
is used to subscribe to or suppress release event. This is
unnecessarily complicated and probably done this way because event
delivery itself was expensive.
This patch implements interface file "cgroup.populated" which can be
used to monitor whether the cgroup's subhierarchy has tasks in it or
not. Its value is 0 if there is no task in the cgroup and its
descendants; otherwise, 1, and kernfs_notify() notificaiton is
triggers when the value changes, which can be monitored through poll
and [di]notify.
This is a lot ligther and simpler and trivially allows delegating
management of subhierarchy - subhierarchy monitoring can block further
propgation simply by putting itself or another process in the root of
the subhierarchy and monitor events that it's interested in from there
without interfering with monitoring higher in the tree.
v2: Patch description updated as per Serge.
v3: "cgroup.subtree_populated" renamed to "cgroup.populated". The
subtree_ prefix was a bit confusing because
"cgroup.subtree_control" uses it to denote the tree rooted at the
cgroup sans the cgroup itself while the populated state includes
the cgroup itself.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Lennart Poettering <lennart@poettering.net>
Pull in driver-core-next to receive kernfs_notify() updates which will
be used by the planned "cgroup.populated" implementation.
Signed-off-by: Tejun Heo <tj@kernel.org>
Support for uevent_helper, aka hotplug, is not required on many systems
these days but it can still be enabled via sysfs or sysctl.
Reported-by: Darren Shepherd <darren.s.shepherd@gmail.com>
Signed-off-by: Michael Marineau <mike@marineau.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cgroup is switching away from multiple hierarchies and will use one
unified default hierarchy where controllers can be dynamically enabled
and disabled per subtree. The default hierarchy will serve as the
unified hierarchy to which all controllers are attached and a css on
the default hierarchy would need to also serve the tasks of descendant
cgroups which don't have the controller enabled - ie. the tree may be
collapsed from leaf towards root when viewed from specific
controllers. This has been implemented through effective css in the
previous patches.
This patch finally implements dynamic subtree controller
enable/disable on the default hierarchy via a new knob -
"cgroup.subtree_control" which controls which controllers are enabled
on the child cgroups. Let's assume a hierarchy like the following.
root - A - B - C
\ D
root's "cgroup.subtree_control" determines which controllers are
enabled on A. A's on B. B's on C and D. This coincides with the
fact that controllers on the immediate sub-level are used to
distribute the resources of the parent. In fact, it's natural to
assume that resource control knobs of a child belong to its parent.
Enabling a controller in "cgroup.subtree_control" declares that
distribution of the respective resources of the cgroup will be
controlled. Note that this means that controller enable states are
shared among siblings.
The default hierarchy has an extra restriction - only cgroups which
don't contain any task may have controllers enabled in
"cgroup.subtree_control". Combined with the other properties of the
default hierarchy, this guarantees that, from the view point of
controllers, tasks are only on the leaf cgroups. In other words, only
leaf csses may contain tasks. This rules out situations where child
cgroups compete against internal tasks of the parent, which is a
competition between two different types of entities without any clear
way to determine resource distribution between the two. Different
controllers handle it differently and all the implemented behaviors
are ambiguous, ad-hoc, cumbersome and/or just wrong. Having this
structural constraints imposed from cgroup core removes the burden
from controller implementations and enables showing one consistent
behavior across all controllers.
When a controller is enabled or disabled, css associations for the
controller in the subtrees of each child should be updated. After
enabling, the whole subtree of a child should point to the new css of
the child. After disabling, the whole subtree of a child should point
to the cgroup's css. This is implemented by first updating cgroup
states such that cgroup_e_css() result points to the appropriate css
and then invoking cgroup_update_dfl_csses() which migrates all tasks
in the affected subtrees to the self cgroup on the default hierarchy.
* When read, "cgroup.subtree_control" lists all the currently enabled
controllers on the children of the cgroup.
* White-space separated list of controller names prefixed with either
'+' or '-' can be written to "cgroup.subtree_control". The ones
prefixed with '+' are enabled on the controller and '-' disabled.
* A controller can be enabled iff the parent's
"cgroup.subtree_control" enables it and disabled iff no child's
"cgroup.subtree_control" has it enabled.
* If a cgroup has tasks, no controller can be enabled via
"cgroup.subtree_control". Likewise, if "cgroup.subtree_control" has
some controllers enabled, tasks can't be migrated into the cgroup.
* All controllers which aren't bound on other hierarchies are
automatically associated with the root cgroup of the default
hierarchy. All the controllers which are bound to the default
hierarchy are listed in the read-only file "cgroup.controllers" in
the root directory.
* "cgroup.controllers" in all non-root cgroups is read-only file whose
content is equal to that of "cgroup.subtree_control" of the parent.
This indicates which controllers can be used in the cgroup's
"cgroup.subtree_control".
This is still experimental and there are some holes, one of which is
that ->can_attach() failure during cgroup_update_dfl_csses() may leave
the cgroups in an undefined state. The issues will be addressed by
future patches.
v2: Non-root cgroups now also have "cgroup.controllers".
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Unified hierarchy implementation would require re-migrating tasks onto
the same cgroup on the default hierarchy to reflect updated effective
csses. Update cgroup_migrate_prepare_dst() so that it accepts NULL as
the destination cgrp. When NULL is specified, the destination is
considered to be the cgroup on the default hierarchy associated with
each css_set.
After this change, the identity check in cgroup_migrate_add_src()
isn't sufficient for noop detection as the associated csses may change
without any cgroup association changing. The only way to tell whether
a migration is noop or not is testing whether the source and
destination csets are identical. The noop check in
cgroup_migrate_add_src() is removed and cset identity test is added to
cgroup_migreate_prepare_dst(). If it's detected that source and
destination csets are identical, the cset is removed removed from
@preloaded_csets and all the migration nodes are cleared which makes
cgroup_migrate() ignore the cset.
Also, make the function append the destination css_sets to
@preloaded_list so that destination css_sets always come after source
css_sets.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Because the default root couldn't have any non-root csses attached to
it, rebinding away from it was always allowed; however, the default
hierarchy will soon host the unified hierarchy and have non-root csses
so the rebind restrictions need to be updated accordingly.
Instead of special casing rebinding from the default hierarchy and
then checking whether the source hierarchy has children cgroups, which
implies non-root csses for !dfl hierarchies, simply check whether the
source hierarchy has non-root csses for the subsystem using
css_next_child().
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
To implement the unified hierarchy behavior, we'll need to be able to
determine the associated cgroup on the default hierarchy from css_set.
Let's add css_set->dfl_cgrp so that it can be accessed conveniently
and efficiently.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Now that effective css handling has been added and iterators updated
accordingly, it's safe to allow cgroup creation in the default
hierarchy. Unblock cgroup creation in the default hierarchy.
As the default hierarchy will implement explicit enabling and
disabling of controllers on each cgroup, suppress automatic css
enabling on cgroup creation.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
After a css finishes offlining, offline_css() mistakenly performs
RCU_INIT_POINTER(css->cgroup->subsys[ss->id], css) which just sets the
cgroup->subsys[] pointer to the current value. The intention was to
clear it after offline is complete, not reassign the same value.
Update it to assign NULL instead of the current value. This makes
cgroup_css() to return NULL once offline is complete. All the
existing users of the function either can handle NULL return already
or guarantee that the css doesn't get offlined.
While this is a bugfix, as css lifetime is currently tied to the
cgroup it belongs to, this bug doesn't cause any actual problems.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Currently, css_task_iter iterates tasks associated with a css by
visiting each css_set associated with the owning cgroup and walking
tasks of each of them. This works fine for !unified hierarchies as
each cgroup has its own css for each associated subsystem on the
hierarchy; however, on the planned unified hierarchy, a cgroup may not
have csses associated and its tasks would be considered associated
with the matching css of the nearest ancestor which has the subsystem
enabled.
This means that on the default unified hierarchy, just walking all
tasks associated with a cgroup isn't enough to walk all tasks which
are associated with the specified css. If any of its children doesn't
have the matching css enabled, task iteration should also include all
tasks from the subtree. We already added cgroup->e_csets[] to list
all css_sets effectively associated with a given css and walk css_sets
on that list instead to achieve such iteration.
This patch updates css_task_iter iteration such that it walks css_sets
on cgroup->e_csets[] instead of cgroup->cset_links if iteration is
requested on an non-dummy css. Thanks to the previous iteration
update, this change can be achieved with the addition of
css_task_iter->ss and minimal updates to css_advance_task_iter() and
css_task_iter_start().
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
This patch reorganizes css_task_iter so that adding effective css
support is easier.
* s/->cset_link/->cset_pos/ and s/->task/->task_pos/ for consistency
* ->origin_css is used to determine whether the iteration reached the
last css_set. Replace it with explicit ->cset_head so that
css_advance_task_iter() doesn't have to know the termination
condition directly.
* css_task_iter_next() currently assumes that it's walking list of
cgrp_cset_link and reaches into the current cset through the current
link to determine the termination conditions for task walking. As
this won't always be true for effective css walking, add
->tasks_head and ->mg_tasks_head and use them to control task
walking so that css_task_iter_next() doesn't have to know how
css_sets are being walked.
This patch doesn't make any behavior changes. The iteration logic
stays unchanged after the patch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
css_next_child() walks the children of the specified css. It does
this by finding the next cgroup and then returning the requested css.
On the default unified hierarchy, a cgroup may not have a css
associated with it even if the hierarchy has the subsystem enabled.
This patch updates css_next_child() so that it skips children without
the requested css associated.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
On the default unified hierarchy, a cgroup may be associated with
csses of its ancestors, which means that a css of a given cgroup may
be associated with css_sets of descendant cgroups. This means that we
can't walk all tasks associated with a css by iterating the css_sets
associated with the cgroup as there are css_sets which are pointing to
the css but linked on the descendants.
This patch adds per-subsystem list heads cgroup->e_csets[]. Any
css_set which is pointing to a css is linked to
css->cgroup->e_csets[$SUBSYS_ID] through
css_set->e_cset_node[$SUBSYS_ID]. The lists are protected by
css_set_rwsem and will allow us to walk all css_sets associated with a
given css so that we can find out all associated tasks.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
In the planned default unified hierarchy, controllers may get
dynamically attached to and detached from a cgroup and a cgroup may
not have csses for all the controllers associated with the hierarchy.
When a cgroup doesn't have its own css for a given controller, the css
of the nearest ancestor with the controller enabled will be used,
which is called the effective css. This patch introduces
cgroup_e_css() and for_each_e_css() to access the effective csses and
convert compare_css_sets(), find_existing_css_set() and
cgroup_migrate() to use the effective csses so that they can handle
cgroups with partial csses correctly.
This means that for two css_sets to be considered identical, they
should have both matching csses and cgroups. compare_css_sets()
already compares both, not for correctness but for optimization. As
this now becomes a matter of correctness, update the comments
accordingly.
For all !default hierarchies, cgroup_e_css() always equals
cgroup_css(), so this patch doesn't change behavior.
While at it, fix incorrect locking comment for for_each_css().
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
944196278d ("cgroup: move ->subsys_mask from cgroupfs_root to
cgroup") moved ->subsys_mask from cgroup_root to cgroup to prepare for
the unified hierarhcy; however, it turns out that carrying the
subsys_mask of the children in the parent, instead of itself, is a lot
more natural. This patch restores cgroup_root->subsys_mask and morphs
cgroup->subsys_mask into cgroup->child_subsys_mask.
* Uses of root->cgrp.subsys_mask are restored to root->subsys_mask.
* Remove automatic setting and clearing of cgrp->subsys_mask and
instead just inherit ->child_subsys_mask from the parent during
cgroup creation. Note that this doesn't affect any current
behaviors.
* Undo __kill_css() separation.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
cgroup_apply_cftypes() skip creating or removing files if the
subsystem is attached to the default hierarchy, which led to missing
files in the root of the default hierarchy.
Skipping made sense when the default hierarchy was dummy; however, now
that the default hierarchy is full functional and planned to be used
as the unified hierarchy, it shouldn't be skipped over.
Reported-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Pull more networking fixes from David Miller:
1) Fix mlx4_en_netpoll implementation, it needs to schedule a NAPI
context, not synchronize it. From Chris Mason.
2) Ipv4 flow input interface should never be zero, it should be
LOOPBACK_IFINDEX instead. From Cong Wang and Julian Anastasov.
3) Properly configure MAC to PHY connection in mvneta devices, from
Thomas Petazzoni.
4) sys_recv should use SYSCALL_DEFINE. From Jan Glauber.
5) Tunnel driver ioctls do not use the correct namespace, fix from
Nicolas Dichtel.
6) Fix memory leak on seccomp filter attach, from Kees Cook.
7) Fix lockdep warning for nested vlans, from Ding Tianhong.
8) Crashes can happen in SCTP due to how the auth_enable value is
managed, fix from Vlad Yasevich.
9) Wireless fixes from John W Linville and co.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (45 commits)
net: sctp: cache auth_enable per endpoint
tg3: update rx_jumbo_pending ring param only when jumbo frames are enabled
vlan: Fix lockdep warning when vlan dev handle notification
seccomp: fix memory leak on filter attach
isdn: icn: buffer overflow in icn_command()
ip6_tunnel: use the right netns in ioctl handler
sit: use the right netns in ioctl handler
ip_tunnel: use the right netns in ioctl handler
net: use SYSCALL_DEFINEx for sys_recv
net: mdio-gpio: Add support for separate MDI and MDO gpio pins
net: mdio-gpio: Add support for active low gpio pins
net: mdio-gpio: Use devm_ functions where possible
ipv4, route: pass 0 instead of LOOPBACK_IFINDEX to fib_validate_source()
ipv4, fib: pass LOOPBACK_IFINDEX instead of 0 to flowi4_iif
mlx4_en: don't use napi_synchronize inside mlx4_en_netpoll
net: mvneta: properly configure the MAC <-> PHY connection in all situations
net: phy: add minimal support for QSGMII PHY
sfc:On MCDI timeout, issue an FLR (and mark MCDI to fail-fast)
mwifiex: fix hung task on command timeout
mwifiex: process event before command response
...
Fix:
BUG: using __this_cpu_write() in preemptible [00000000] code: systemd-udevd/497
caller is __this_cpu_preempt_check+0x13/0x20
CPU: 3 PID: 497 Comm: systemd-udevd Tainted: G W 3.15.0-rc1 #9
Hardware name: Hewlett-Packard HP EliteBook 8470p/179B, BIOS 68ICF Ver. F.02 04/27/2012
Call Trace:
check_preemption_disabled+0xe1/0xf0
__this_cpu_preempt_check+0x13/0x20
touch_nmi_watchdog+0x28/0x40
Reported-by: Luis Henriques <luis.henriques@canonical.com>
Tested-by: Luis Henriques <luis.henriques@canonical.com>
Cc: Eric Piel <eric.piel@tremplin-utc.net>
Cc: Robert Moore <robert.moore@intel.com>
Cc: Lv Zheng <lv.zheng@intel.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The first is to remove a duplication of creating debugfs files that
already exist and causes an error report to be printed due to the
failure of the second creation.
The second is a memory leak fix that was introduced in 3.14.
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Merge tag 'trace-fixes-v3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"This contains two fixes.
The first is to remove a duplication of creating debugfs files that
already exist and causes an error report to be printed due to the
failure of the second creation.
The second is a memory leak fix that was introduced in 3.14"
* tag 'trace-fixes-v3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing/uprobes: Fix uprobe_cpu_buffer memory leak
tracing: Do not try to recreated toplevel set_ftrace_* files
Pull timer fixes from Thomas Gleixner:
"Viresh unearthed the following three hickups in the timer/timekeeping
code:
- Negated check for the result of a clock event selection
- A missing early exit in the jiffies update path which causes
update_wall_time to be called for nothing causing lock contention
and wasted cycles in the timer interrupt
- Checking a variable in the NOHZ code enable code for true which can
only be set by that very code after the check succeeds. That
results in a rock solid runtime disablement of that feature"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tick-sched: Check tick_nohz_enabled in tick_nohz_switch_to_nohz()
tick-sched: Don't call update_wall_time() when delta is lesser than tick_period
tick-common: Fix wrong check in tick_check_replacement()
If we hit the retry path, we'll call parse_cgroupfs_options() again,
but the string we pass to it has been modified by the previous call
to this function.
This bug can be observed by:
# mount -t cgroup -o name=foo,cpuset xxx /mnt && umount /mnt && \
mount -t cgroup -o name=foo,cpuset xxx /mnt
mount: wrong fs type, bad option, bad superblock on xxx,
missing codepage or helper program, or other error
...
The second mount passed "name=foo,cpuset" to the parser, and then it
hit the retry path and call the parser again, but this time the string
passed to the parser is "name=foo".
To fix this, we avoid calling parse_cgroupfs_options() again in this
case.
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
We need to do it like we do for the other higher priority classes..
Signed-off-by: Kirill Tkhai <tkhai@yandex.ru>
Cc: Michael wang <wangyun@linux.vnet.ibm.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/336561397137116@web27h.yandex.ru
Signed-off-by: Ingo Molnar <mingo@kernel.org>
With the restructing of the function tracer working with instances, the
"top level" buffer is a bit special, as the function tracing is mapped
to the same set of filters. This is done by using a "global_ops" descriptor
and having the "set_ftrace_filter" and "set_ftrace_notrace" map to it.
When an instance is created, it creates the same files but its for the
local instance and not the global_ops.
The issues is that the local instance creation shares some code with
the global instance one and we end up trying to create th top level
"set_ftrace_*" files twice, and on boot up, we get an error like this:
Could not create debugfs 'set_ftrace_filter' entry
Could not create debugfs 'set_ftrace_notrace' entry
The reason they failed to be created was because they were created
twice, and the second time gives this error as you can not create the
same file twice.
Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Pull networking fixes from David Miller:
1) Fix BPF filter validation of netlink attribute accesses, from
Mathias Kruase.
2) Netfilter conntrack generation seqcount not initialized properly,
from Andrey Vagin.
3) Fix comparison mask computation on big-endian in nft_cmp_fast(),
from Patrick McHardy.
4) Properly limit MTU over ipv6, from Eric Dumazet.
5) Fix seccomp system call argument population on 32-bit, from Daniel
Borkmann.
6) skb_network_protocol() should not use hard-coded ETH_HLEN, instead
skb->mac_len needs to be used. From Vlad Yasevich.
7) We have several cases of using socket based communications to
implement a tunnel. For example, some tunnels are encapsulations
over UDP so we use an internal kernel UDP socket to do the
transmits.
These tunnels should behave just like other software devices and
pass the packets on down to the next layer.
Most importantly we want the top-level socket (eg TCP) that created
the traffic to be charged for the SKB memory.
However, once you get into the IP output path, we have code that
assumed that whatever was attached to skb->sk is an IP socket.
To keep the top-level socket being charged for the SKB memory,
whilst satisfying the needs of the IP output path, we now pass in an
explicit 'sk' argument.
From Eric Dumazet.
8) ping_init_sock() leaks group info, from Xiaoming Wang.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (33 commits)
cxgb4: use the correct max size for firmware flash
qlcnic: Fix MSI-X initialization code
ip6_gre: don't allow to remove the fb_tunnel_dev
ipv4: add a sock pointer to dst->output() path.
ipv4: add a sock pointer to ip_queue_xmit()
driver/net: cosa driver uses udelay incorrectly
at86rf230: fix __at86rf230_read_subreg function
at86rf230: remove check if AVDD settled
net: cadence: Add architecture dependencies
net: Start with correct mac_len in skb_network_protocol
Revert "net: sctp: Fix a_rwnd/rwnd management to reflect real state of the receiver's buffer"
cxgb4: Save the correct mac addr for hw-loopback connections in the L2T
net: filter: seccomp: fix wrong decoding of BPF_S_ANC_SECCOMP_LD_W
seccomp: fix populating a0-a5 syscall args in 32-bit x86 BPF
qlcnic: Do not disable SR-IOV when VFs are assigned to VMs
qlcnic: Fix QLogic application/driver interface for virtual NIC configuration
qlcnic: Fix PVID configuration on eSwitch port.
qlcnic: Fix max ring count calculation
qlcnic: Fix to send INIT_NIC_FUNC as first mailbox.
qlcnic: Fix panic due to uninitialzed delayed_work struct in use.
...
In tick_do_update_jiffies64() we are processing ticks only if delta is
greater than tick_period. This is what we are supposed to do here and
it broke a bit with this patch:
commit 47a1b796 (tick/timekeeping: Call update_wall_time outside the
jiffies lock)
With above patch, we might end up calling update_wall_time() even if
delta is found to be smaller that tick_period. Fix this by returning
when the delta is less than tick period.
[ tglx: Made it a 3 liner and massaged changelog ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linaro-kernel@lists.linaro.org
Cc: fweisbec@gmail.com
Cc: Arvind.Chauhan@arm.com
Cc: linaro-networking@linaro.org
Cc: John Stultz <john.stultz@linaro.org>
Cc: <stable@vger.kernel.org> # v3.14+
Link: http://lkml.kernel.org/r/80afb18a494b0bd9710975bcc4de134ae323c74f.1397537987.git.viresh.kumar@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
smp_read_barrier_depends() can be used if there is data dependency between
the readers - i.e. if the read operation after the barrier uses address
that was obtained from the read operation before the barrier.
In this file, there is only control dependency, no data dependecy, so the
use of smp_read_barrier_depends() is incorrect. The code could fail in the
following way:
* the cpu predicts that idx < entries is true and starts executing the
body of the for loop
* the cpu fetches map->extent[0].first and map->extent[0].count
* the cpu fetches map->nr_extents
* the cpu verifies that idx < extents is true, so it commits the
instructions in the body of the for loop
The problem is that in this scenario, the cpu read map->extent[0].first
and map->nr_extents in the wrong order. We need a full read memory barrier
to prevent it.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus reports that on 32-bit x86 Chromium throws the following seccomp
resp. audit log messages:
audit: type=1326 audit(1397359304.356:28108): auid=500 uid=500
gid=500 ses=2 subj=unconfined_u:unconfined_r:chrome_sandbox_t:s0-s0:c0.c1023
pid=3677 comm="chrome" exe="/opt/google/chrome/chrome" sig=0
syscall=172 compat=0 ip=0xb2dd9852 code=0x30000
audit: type=1326 audit(1397359304.356:28109): auid=500 uid=500
gid=500 ses=2 subj=unconfined_u:unconfined_r:chrome_sandbox_t:s0-s0:c0.c1023
pid=3677 comm="chrome" exe="/opt/google/chrome/chrome" sig=0 syscall=5
compat=0 ip=0xb2dd9852 code=0x50000
These audit messages are being triggered via audit_seccomp() through
__secure_computing() in seccomp mode (BPF) filter with seccomp return
codes 0x30000 (== SECCOMP_RET_TRAP) and 0x50000 (== SECCOMP_RET_ERRNO)
during filter runtime. Moreover, Linus reports that x86_64 Chromium
seems fine.
The underlying issue that explains this is that the implementation of
populate_seccomp_data() is wrong. Our seccomp data structure sd that
is being shared with user ABI is:
struct seccomp_data {
int nr;
__u32 arch;
__u64 instruction_pointer;
__u64 args[6];
};
Therefore, a simple cast to 'unsigned long *' for storing the value of
the syscall argument via syscall_get_arguments() is just wrong as on
32-bit x86 (or any other 32bit arch), it would result in storing a0-a5
at wrong offsets in args[] member, and thus i) could leak stack memory
to user space and ii) tampers with the logic of seccomp BPF programs
that read out and check for syscall arguments:
syscall_get_arguments(task, regs, 0, 1, (unsigned long *) &sd->args[0]);
Tested on 32-bit x86 with Google Chrome, unfortunately only via remote
test machine through slow ssh X forwarding, but it fixes the issue on
my side. So fix it up by storing args in type correct variables, gcc
is clever and optimizes the copy away in other cases, e.g. x86_64.
Fixes: bd4cf0ed33 ("net: filter: rework/optimize internal BPF interpreter's instruction set")
Reported-and-bisected-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commits 11d4616bd0 ("futex: revert back to the explicit waiter
counting code") and 69cd9eba38 ("futex: avoid race between requeue and
wake") changed some of the finer details of how we think about futexes.
One was a late fix and the other a consequence of overlooking the whole
requeuing logic.
The first change caused our documentation to be incorrect, and the
second made us aware that we need to explicitly add more details to it.
Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull vfs updates from Al Viro:
"The first vfs pile, with deep apologies for being very late in this
window.
Assorted cleanups and fixes, plus a large preparatory part of iov_iter
work. There's a lot more of that, but it'll probably go into the next
merge window - it *does* shape up nicely, removes a lot of
boilerplate, gets rid of locking inconsistencie between aio_write and
splice_write and I hope to get Kent's direct-io rewrite merged into
the same queue, but some of the stuff after this point is having
(mostly trivial) conflicts with the things already merged into
mainline and with some I want more testing.
This one passes LTP and xfstests without regressions, in addition to
usual beating. BTW, readahead02 in ltp syscalls testsuite has started
giving failures since "mm/readahead.c: fix readahead failure for
memoryless NUMA nodes and limit readahead pages" - might be a false
positive, might be a real regression..."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
missing bits of "splice: fix racy pipe->buffers uses"
cifs: fix the race in cifs_writev()
ceph_sync_{,direct_}write: fix an oops on ceph_osdc_new_request() failure
kill generic_file_buffered_write()
ocfs2_file_aio_write(): switch to generic_perform_write()
ceph_aio_write(): switch to generic_perform_write()
xfs_file_buffered_aio_write(): switch to generic_perform_write()
export generic_perform_write(), start getting rid of generic_file_buffer_write()
generic_file_direct_write(): get rid of ppos argument
btrfs_file_aio_write(): get rid of ppos
kill the 5th argument of generic_file_buffered_write()
kill the 4th argument of __generic_file_aio_write()
lustre: don't open-code kernel_recvmsg()
ocfs2: don't open-code kernel_recvmsg()
drbd: don't open-code kernel_recvmsg()
constify blk_rq_map_user_iov() and friends
lustre: switch to kernel_sendmsg()
ocfs2: don't open-code kernel_sendmsg()
take iov_iter stuff to mm/iov_iter.c
process_vm_access: tidy up a bit
...
design of tracepoints and how a user could register a tracepoint
and have that tracepoint not be activated but no error was shown.
The design was for an out of tree module but broke in tree users.
The clean up was to remove the saving of the hash table of tracepoint
names such that they can be enabled before they exist (enabling
a module tracepoint before that module is loaded). This added more
complexity than needed. The clean up was to remove that code and
just enable tracepoints that exist or fail if they do not.
This removed a lot of code as well as the complexity that it brought.
As a side effect, instead of registering a tracepoint by its name,
the tracepoint needs to be registered with the tracepoint descriptor.
This removes having to duplicate the tracepoint names that are
enabled.
The second patch was added that simplified the way modules were
searched for.
This cleanup required changes that were in the 3.15 queue as well as
some changes that were added late in the 3.14-rc cycle. This final
change waited till the two were merged in upstream and then the
change was added and full tests were run. Unfortunately, the
test found some errors, but after it was already submitted to the
for-next branch and not to be rebased. Sparse errors were detected
by Fengguang Wu's bot tests, and my internal tests discovered that
the anonymous union initialization triggered a bug in older gcc compilers.
Luckily, there was a bugzilla for the gcc bug which gave a work around
to the problem. The third and fourth patch handled the sparse error
and the gcc bug respectively.
A final patch was tagged along to fix a missing documentation for
the README file.
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Merge tag 'trace-3.15-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull more tracing updates from Steven Rostedt:
"This includes the final patch to clean up and fix the issue with the
design of tracepoints and how a user could register a tracepoint and
have that tracepoint not be activated but no error was shown.
The design was for an out of tree module but broke in tree users. The
clean up was to remove the saving of the hash table of tracepoint
names such that they can be enabled before they exist (enabling a
module tracepoint before that module is loaded). This added more
complexity than needed. The clean up was to remove that code and just
enable tracepoints that exist or fail if they do not.
This removed a lot of code as well as the complexity that it brought.
As a side effect, instead of registering a tracepoint by its name, the
tracepoint needs to be registered with the tracepoint descriptor.
This removes having to duplicate the tracepoint names that are
enabled.
The second patch was added that simplified the way modules were
searched for.
This cleanup required changes that were in the 3.15 queue as well as
some changes that were added late in the 3.14-rc cycle. This final
change waited till the two were merged in upstream and then the change
was added and full tests were run. Unfortunately, the test found some
errors, but after it was already submitted to the for-next branch and
not to be rebased. Sparse errors were detected by Fengguang Wu's bot
tests, and my internal tests discovered that the anonymous union
initialization triggered a bug in older gcc compilers. Luckily, there
was a bugzilla for the gcc bug which gave a work around to the
problem. The third and fourth patch handled the sparse error and the
gcc bug respectively.
A final patch was tagged along to fix a missing documentation for the
README file"
* tag 'trace-3.15-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Add missing function triggers dump and cpudump to README
tracing: Fix anonymous unions in struct ftrace_event_call
tracepoint: Fix sparse warnings in tracepoint.c
tracepoint: Simplify tracepoint module search
tracepoint: Use struct pointer instead of name hash for reg/unreg tracepoints
Pull audit updates from Eric Paris.
* git://git.infradead.org/users/eparis/audit: (28 commits)
AUDIT: make audit_is_compat depend on CONFIG_AUDIT_COMPAT_GENERIC
audit: renumber AUDIT_FEATURE_CHANGE into the 1300 range
audit: do not cast audit_rule_data pointers pointlesly
AUDIT: Allow login in non-init namespaces
audit: define audit_is_compat in kernel internal header
kernel: Use RCU_INIT_POINTER(x, NULL) in audit.c
sched: declare pid_alive as inline
audit: use uapi/linux/audit.h for AUDIT_ARCH declarations
syscall_get_arch: remove useless function arguments
audit: remove stray newline from audit_log_execve_info() audit_panic() call
audit: remove stray newlines from audit_log_lost messages
audit: include subject in login records
audit: remove superfluous new- prefix in AUDIT_LOGIN messages
audit: allow user processes to log from another PID namespace
audit: anchor all pid references in the initial pid namespace
audit: convert PPIDs to the inital PID namespace.
pid: get pid_t ppid of task in init_pid_ns
audit: rename the misleading audit_get_context() to audit_take_context()
audit: Add generic compat syscall support
audit: Add CONFIG_HAVE_ARCH_AUDITSYSCALL
...
that commit has fixed only the parts of that mess in fs/splice.c itself;
there had been more in several other ->splice_read() instances...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
debug_mutex_unlock() would bail when !debug_locks and forgets to
actually unlock.
Reported-by: "Michael L. Semon" <mlsemon35@gmail.com>
Reported-by: "Kirill A. Shutemov" <kirill@shutemov.name>
Reported-by: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Fixes: 6f008e72cd ("locking/mutex: Fix debug checks")
Tested-by: Dave Jones <davej@redhat.com>
Cc: Jason Low <jason.low2@hp.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140410141559.GE13658@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Sasha reported that lockdep claims that the following commit:
made numa_group.lock interrupt unsafe:
156654f491 ("sched/numa: Move task_numa_free() to __put_task_struct()")
While I don't see how that could be, given the commit in question moved
task_numa_free() from one irq enabled region to another, the below does
make both gripes and lockups upon gripe with numa=fake=4 go away.
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Fixes: 156654f491 ("sched/numa: Move task_numa_free() to __put_task_struct()")
Signed-off-by: Mike Galbraith <bitbucket@online.de>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: torvalds@linux-foundation.org
Cc: mgorman@suse.com
Cc: akpm@linux-foundation.org
Cc: Dave Jones <davej@redhat.com>
Link: http://lkml.kernel.org/r/1396860915.5170.5.camel@marge.simpson.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The debugfs tracing README file lists all the function triggers except for
dump and cpudump. These should be added too.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
