This reverts commit f3a2aebdd6.
The commit enabled looking up v1 cgroups via cgroup_get_from_file().
However, there are multiple users, including CLONE_INTO_CGROUP, which have
been assuming that it would only look up v2 cgroups. Returning v1 cgroups
breaks them.
Let's revert the commit and retry later with a separate lookup interface
which allows both v1 and v2.
Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/000000000000385cbf05ea3f1862@google.com
Cc: Yosry Ahmed <yosryahmed@google.com>
The commit 74e4b956eb incorrectly wrapped kernfs_walk_and_get
(might_sleep) under css_set_lock (spinlock). css_set_lock is needed by
__cset_cgroup_from_root to ensure stable cset->cgrp_links but not for
kernfs_walk_and_get.
We only need to make sure that the returned root_cgrp won't be freed
under us. This is given in the case of global root because it is static
(cgrp_dfl_root.cgrp). When the root_cgrp is lower in the hierarchy, it
is pinned by cgroup_ns->root_cset (and `current` task cannot switch
namespace asynchronously so ns_proxy pins cgroup_ns).
Note this reasoning won't hold for root cgroups in v1 hierarchies,
therefore create a special-cased helper function just for the default
hierarchy.
Fixes: 74e4b956eb ("cgroup: Honor caller's cgroup NS when resolving path")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
* cpuset now support isolated cpus.partition type, which will enable dynamic
CPU isolation.
* pids.peak added to remember the max number of pids used.
* Holes in cgroup namespace plugged.
* Internal cleanups.
Note that for-6.1-fixes was pulled into for-6.1 twice. Both were for
follow-up cleanups and each merge commit has details.
Also, 8a693f7766 ("cgroup: Remove CFTYPE_PRESSURE") removes the flag used
by PSI changes in the tip tree and the merged result won't compile due to
the missing flag. Simply removing the struct init lines specifying the flag
is the correct resolution. linux-next already contains the correct fix:
https://lkml.kernel.org/r/20220912161812.072aaa3b@canb.auug.org.au
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Merge tag 'cgroup-for-6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:
- cpuset now support isolated cpus.partition type, which will enable
dynamic CPU isolation
- pids.peak added to remember the max number of pids used
- holes in cgroup namespace plugged
- internal cleanups
* tag 'cgroup-for-6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (25 commits)
cgroup: use strscpy() is more robust and safer
iocost_monitor: reorder BlkgIterator
cgroup: simplify code in cgroup_apply_control
cgroup: Make cgroup_get_from_id() prettier
cgroup/cpuset: remove unreachable code
cgroup: Remove CFTYPE_PRESSURE
cgroup: Improve cftype add/rm error handling
kselftest/cgroup: Add cpuset v2 partition root state test
cgroup/cpuset: Update description of cpuset.cpus.partition in cgroup-v2.rst
cgroup/cpuset: Make partition invalid if cpumask change violates exclusivity rule
cgroup/cpuset: Relocate a code block in validate_change()
cgroup/cpuset: Show invalid partition reason string
cgroup/cpuset: Add a new isolated cpus.partition type
cgroup/cpuset: Relax constraints to partition & cpus changes
cgroup/cpuset: Allow no-task partition to have empty cpuset.cpus.effective
cgroup/cpuset: Miscellaneous cleanups & add helper functions
cgroup/cpuset: Enable update_tasks_cpumask() on top_cpuset
cgroup: add pids.peak interface for pids controller
cgroup: Remove data-race around cgrp_dfl_visible
cgroup: Fix build failure when CONFIG_SHRINKER_DEBUG
...
Here is the big set of driver core and debug printk changes for 6.1-rc1.
Included in here is:
- dynamic debug updates for the core and the drm subsystem. The
drm changes have all been acked by the relevant maintainers.
- kernfs fixes for syzbot reported problems
- kernfs refactors and updates for cgroup requirements
- magic number cleanups and removals from the kernel tree (they
were not being used and they really did not actually do
anything.)
- other tiny cleanups
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here is the big set of driver core and debug printk changes for
6.1-rc1. Included in here is:
- dynamic debug updates for the core and the drm subsystem. The drm
changes have all been acked by the relevant maintainers
- kernfs fixes for syzbot reported problems
- kernfs refactors and updates for cgroup requirements
- magic number cleanups and removals from the kernel tree (they were
not being used and they really did not actually do anything)
- other tiny cleanups
All of these have been in linux-next for a while with no reported
issues"
* tag 'driver-core-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (74 commits)
docs: filesystems: sysfs: Make text and code for ->show() consistent
Documentation: NBD_REQUEST_MAGIC isn't a magic number
a.out: restore CMAGIC
device property: Add const qualifier to device_get_match_data() parameter
drm_print: add _ddebug descriptor to drm_*dbg prototypes
drm_print: prefer bare printk KERN_DEBUG on generic fn
drm_print: optimize drm_debug_enabled for jump-label
drm-print: add drm_dbg_driver to improve namespace symmetry
drm-print.h: include dyndbg header
drm_print: wrap drm_*_dbg in dyndbg descriptor factory macro
drm_print: interpose drm_*dbg with forwarding macros
drm: POC drm on dyndbg - use in core, 2 helpers, 3 drivers.
drm_print: condense enum drm_debug_category
debugfs: use DEFINE_SHOW_ATTRIBUTE to define debugfs_regset32_fops
driver core: use IS_ERR_OR_NULL() helper in device_create_groups_vargs()
Documentation: ENI155_MAGIC isn't a magic number
Documentation: NBD_REPLY_MAGIC isn't a magic number
nbd: remove define-only NBD_MAGIC, previously magic number
Documentation: FW_HEADER_MAGIC isn't a magic number
Documentation: EEPROM_MAGIC_VALUE isn't a magic number
...
The implementation of strscpy() is more robust and safer.
That's now the recommended way to copy NUL terminated strings.
Signed-off-by: ye xingchen <ye.xingchen@zte.com.cn>
Signed-off-by: Tejun Heo <tj@kernel.org>
It could directly return 'cgroup_update_dfl_csses' to simplify code.
Signed-off-by: William Dean <williamsukatube@163.com>
Reviewed-by: Mukesh Ojha <quic_mojha@quicinc.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
After merging 836ac87d ("cgroup: fix cgroup_get_from_id") into for-6.1, its
combination with two commits in for-6.1 - 4534dee9 ("cgroup: cgroup: Honor
caller's cgroup NS when resolving cgroup id") and fa7e439c ("cgroup:
Homogenize cgroup_get_from_id() return value") - makes the gotos in the
error handling path too ugly while not adding anything of value.
All that the gotos are saving is one extra kernfs_put() call. Let's remove
the gotos and perform error returns directly.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Michal Koutný <mkoutny@suse.com>
for-6.0 has the following fix for cgroup_get_from_id().
836ac87d ("cgroup: fix cgroup_get_from_id")
which conflicts with the following two commits in for-6.1.
4534dee9 ("cgroup: cgroup: Honor caller's cgroup NS when resolving cgroup id")
fa7e439c ("cgroup: Homogenize cgroup_get_from_id() return value")
While the resolution is straightforward, the code ends up pretty ugly
afterwards. Let's pull for-6.0-fixes into for-6.1 so that the code can be
fixed up there.
Signed-off-by: Tejun Heo <tj@kernel.org>
cgroup has to be one kernfs dir, otherwise kernel panic is caused,
especially cgroup id is provide from userspace.
Reported-by: Marco Patalano <mpatalan@redhat.com>
Fixes: 6b658c4863 ("scsi: cgroup: Add cgroup_get_from_id()")
Cc: Muneendra <muneendra.kumar@broadcom.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Acked-by: Mukesh Ojha <quic_mojha@quicinc.com>
Cc: stable@vger.kernel.org # v5.14+
Signed-off-by: Tejun Heo <tj@kernel.org>
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Merge 6.0-rc5 into driver-core-next
We need the driver core and debugfs changes in this branch.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
PSI accounts stalls for each cgroup separately and aggregates it
at each level of the hierarchy. This may cause non-negligible overhead
for some workloads when under deep level of the hierarchy.
commit 3958e2d0c3 ("cgroup: make per-cgroup pressure stall tracking configurable")
make PSI to skip per-cgroup stall accounting, only account system-wide
to avoid this each level overhead.
But for our use case, we also want leaf cgroup PSI stats accounted for
userspace adjustment on that cgroup, apart from only system-wide adjustment.
So this patch introduce a per-cgroup PSI accounting disable/re-enable
interface "cgroup.pressure", which is a read-write single value file that
allowed values are "0" and "1", the defaults is "1" so per-cgroup
PSI stats is enabled by default.
Implementation details:
It should be relatively straight-forward to disable and re-enable
state aggregation, time tracking, averaging on a per-cgroup level,
if we can live with losing history from while it was disabled.
I.e. the avgs will restart from 0, total= will have gaps.
But it's hard or complex to stop/restart groupc->tasks[] updates,
which is not implemented in this patch. So we always update
groupc->tasks[] and PSI_ONCPU bit in psi_group_change() even when
the cgroup PSI stats is disabled.
Suggested-by: Johannes Weiner <hannes@cmpxchg.org>
Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lkml.kernel.org/r/20220907090332.2078-1-zhouchengming@bytedance.com
cgroup_psi() can't return psi_group for root cgroup, so we have many
open code "psi = cgroup_ino(cgrp) == 1 ? &psi_system : cgrp->psi".
This patch move cgroup_psi() definition to <linux/psi.h>, in which
we can return psi_system for root cgroup, so can handle all cgroups.
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lore.kernel.org/r/20220825164111.29534-9-zhouchengming@bytedance.com
Now PSI already tracked workload pressure stall information for
CPU, memory and IO. Apart from these, IRQ/SOFTIRQ could have
obvious impact on some workload productivity, such as web service
workload.
When CONFIG_IRQ_TIME_ACCOUNTING, we can get IRQ/SOFTIRQ delta time
from update_rq_clock_task(), in which we can record that delta
to CPU curr task's cgroups as PSI_IRQ_FULL status.
Note we don't use PSI_IRQ_SOME since IRQ/SOFTIRQ always happen in
the current task on the CPU, make nothing productive could run
even if it were runnable, so we only use PSI_IRQ_FULL.
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lore.kernel.org/r/20220825164111.29534-8-zhouchengming@bytedance.com
commit 3958e2d0c3 ("cgroup: make per-cgroup pressure stall tracking configurable")
make PSI can be configured to skip per-cgroup stall accounting. And
doesn't expose PSI files in cgroup hierarchy.
This patch do the same thing when psi_disabled.
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lore.kernel.org/r/20220825164111.29534-3-zhouchengming@bytedance.com
CFTYPE_PRESSURE is used to flag PSI related files so that they are not
created if PSI is disabled during boot. It's a bit weird to use a generic
flag to mark a specific file type. Let's instead move the PSI files into its
own cftypes array and add/rm them conditionally. This is a bit more code but
cleaner.
No userland visible changes.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Let's track whether a cftype is currently added or not using a new flag
__CFTYPE_ADDED so that duplicate operations can be failed safely and
consistently allow using empty cftypes.
Signed-off-by: Tejun Heo <tj@kernel.org>
There's a seemingly harmless data-race around cgrp_dfl_visible detected by
kernel concurrency sanitizer. Let's remove it by throwing WRITE/READ_ONCE at
it.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Abhishek Shah <abhishek.shah@columbia.edu>
Cc: Gabriel Ryan <gabe@cs.columbia.edu>
Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Link: https://lore.kernel.org/netdev/20220819072256.fn7ctciefy4fc4cu@wittgenstein/
Add cgroup_file_show() which allows toggling visibility of a cgroup file
using the new kernfs_show(). This will be used to hide psi interface files
on cgroups where it's disabled.
Cc: Chengming Zhou <zhouchengming@bytedance.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Tested-by: Chengming Zhou <zhouchengming@bytedance.com>
Reviewed-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20220828050440.734579-10-tj@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cgroup id is user provided datum hence extend its return domain to
include possible error reason (similar to cgroup_get_from_fd()).
This change also fixes commit d4ccaf58a8 ("bpf: Introduce cgroup
iter") that would use NULL instead of proper error handling in
d4ccaf58a8 ("bpf: Introduce cgroup iter").
Additionally, neither of: fc_appid_store, bpf_iter_attach_cgroup,
mem_cgroup_get_from_ino (callers of cgroup_get_from_fd) is built without
CONFIG_CGROUPS (depends via CONFIG_BLK_CGROUP, direct, transitive
CONFIG_MEMCG respectively) transitive, so drop the singular definition
not needed with !CONFIG_CGROUPS.
Fixes: d4ccaf58a8 ("bpf: Introduce cgroup iter")
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cgroup ids are resolved in the global scope. That may be needed sometime
(in future) but currently it violates virtual view provided through
cgroup namespaces.
There are currently following users of the resolution:
- fc_appid_store
- bpf_iter_attach_cgroup
- mem_cgroup_get_from_ino
None of the is a called on behalf of kernel but the resolution is made
with proper userspace context, hence the default to current->nsproxy
makes sens. (This doesn't rule out cgroup_get_from_id with cgroup NS
parameter in the future.)
Since cgroup ids are defined on v2 hierarchy only, we simply check
existence in the cgroup namespace by looking at ancestry on the default
hierarchy.
Fixes: 6b658c4863 ("scsi: cgroup: Add cgroup_get_from_id()")
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
cgroup_get_from_path() is not widely used function. Its callers presume
the path is resolved under cgroup namespace. (There is one caller
currently and resolving in init NS won't make harm (netfilter). However,
future users may be subject to different effects when resolving
globally.)
Since, there's currently no use for the global resolution, modify the
existing function to take cgroup NS into account.
Fixes: a79a908fd2 ("cgroup: introduce cgroup namespaces")
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Root cause:
The rebind_subsystems() is no lock held when move css object from A
list to B list,then let B's head be treated as css node at
list_for_each_entry_rcu().
Solution:
Add grace period before invalidating the removed rstat_css_node.
Reported-by: Jing-Ting Wu <jing-ting.wu@mediatek.com>
Suggested-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Jing-Ting Wu <jing-ting.wu@mediatek.com>
Tested-by: Jing-Ting Wu <jing-ting.wu@mediatek.com>
Link: https://lore.kernel.org/linux-arm-kernel/d8f0bc5e2fb6ed259f9334c83279b4c011283c41.camel@mediatek.com/T/
Acked-by: Mukesh Ojha <quic_mojha@quicinc.com>
Fixes: a7df69b81a ("cgroup: rstat: support cgroup1")
Cc: stable@vger.kernel.org # v5.13+
Signed-off-by: Tejun Heo <tj@kernel.org>
Bringing up a CPU may involve creating and destroying tasks which requires
read-locking threadgroup_rwsem, so threadgroup_rwsem nests inside
cpus_read_lock(). However, cpuset's ->attach(), which may be called with
thredagroup_rwsem write-locked, also wants to disable CPU hotplug and
acquires cpus_read_lock(), leading to a deadlock.
Fix it by guaranteeing that ->attach() is always called with CPU hotplug
disabled and removing cpus_read_lock() call from cpuset_attach().
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-and-tested-by: Imran Khan <imran.f.khan@oracle.com>
Reported-and-tested-by: Xuewen Yan <xuewen.yan@unisoc.com>
Fixes: 05c7b7a92c ("cgroup/cpuset: Fix a race between cpuset_attach() and cpu hotplug")
Cc: stable@vger.kernel.org # v5.17+
psi_trigger_create()'s 'nbytes' parameter is not used, so we can remove it.
Signed-off-by: Hao Jia <jiahao.os@bytedance.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Every cgroup knows all its ancestors through its ->ancestor_ids[]. There's
no advantage to remembering the IDs instead of the pointers directly and
this makes the array useless for finding an actual ancestor cgroup forcing
cgroup_ancestor() to iteratively walk up the hierarchy instead. Let's
replace cgroup->ancestor_ids[] with ->ancestors[] and remove the walking-up
from cgroup_ancestor().
While at it, improve comments around cgroup_root->cgrp_ancestor_storage.
This patch shouldn't cause user-visible behavior differences.
v2: Update cgroup_ancestor() to use ->ancestors[].
v3: cgroup_root->cgrp_ancestor_storage's type is updated to match
cgroup->ancestors[]. Better comments.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
cgroup_get_from_file() currently fails with -EBADF if called on cgroup
v1. However, the current implementation works on cgroup v1 as well, so
the restriction is unnecessary.
This enabled cgroup_get_from_fd() to work on cgroup v1, which would be
the only thing stopping bpf cgroup_iter from supporting cgroup v1.
Signed-off-by: Yosry Ahmed <yosryahmed@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Hao Luo <haoluo@google.com>
Link: https://lore.kernel.org/r/20220805214821.1058337-3-haoluo@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
* threadgroup_rwsem write locking is skipped when configuring controllers in
empty subtrees. Combined with CLONE_INTO_CGROUP, this allows the common
static usage pattern to not grab threadgroup_rwsem at all (glibc still
doesn't seem ready for CLONE_INTO_CGROUP unfortunately).
* threadgroup_rwsem used to be put into non-percpu mode by default due to
latency concerns in specific use cases. There's no reason for everyone
else to pay for it. Make the behavior optional.
* psi no longer allocates memory when disabled.
along with some code cleanups.
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Merge tag 'cgroup-for-5.20' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:
"Several core optimizations:
- threadgroup_rwsem write locking is skipped when configuring
controllers in empty subtrees.
Combined with CLONE_INTO_CGROUP, this allows the common static
usage pattern to not grab threadgroup_rwsem at all (glibc still
doesn't seem ready for CLONE_INTO_CGROUP unfortunately).
- threadgroup_rwsem used to be put into non-percpu mode by default
due to latency concerns in specific use cases. There's no reason
for everyone else to pay for it. Make the behavior optional.
- psi no longer allocates memory when disabled.
... along with some code cleanups"
* tag 'cgroup-for-5.20' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: Skip subtree root in cgroup_update_dfl_csses()
cgroup: remove "no" prefixed mount options
cgroup: Make !percpu threadgroup_rwsem operations optional
cgroup: Add "no" prefixed mount options
cgroup: Elide write-locking threadgroup_rwsem when updating csses on an empty subtree
cgroup.c: remove redundant check for mixable cgroup in cgroup_migrate_vet_dst
cgroup.c: add helper __cset_cgroup_from_root to cleanup duplicated codes
psi: dont alloc memory for psi by default
The cgroup_update_dfl_csses() function updates css associations when a
cgroup's subtree_control file is modified. Any changes made to a cgroup's
subtree_control file, however, will only affect its descendants but not
the cgroup itself. So there is no point in migrating csses associated
with that cgroup. We can skip them instead.
Signed-off-by: Waiman Long <longman@redhat.com>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
30312730bd ("cgroup: Add "no" prefixed mount options") added "no" prefixed
mount options to allow turning them off and 6a010a49b6 ("cgroup: Make
!percpu threadgroup_rwsem operations optional") added one more "no" prefixed
mount option. However, Michal pointed out that the "no" prefixed options
aren't necessary in allowing mount options to be turned off:
# grep group /proc/mounts
cgroup2 /sys/fs/cgroup cgroup2 rw,nosuid,nodev,relatime,nsdelegate,memory_recursiveprot 0 0
# mount -o remount,nsdelegate,memory_recursiveprot none /sys/fs/cgroup
# grep cgroup /proc/mounts
cgroup2 /sys/fs/cgroup cgroup2 rw,relatime,nsdelegate,memory_recursiveprot 0 0
Note that this is different from the remount behavior when the mount(1) is
invoked without the device argument - "none":
# grep cgroup /proc/mounts
cgroup2 /sys/fs/cgroup cgroup2 rw,nosuid,nodev,noexec,relatime,nsdelegate,memory_recursiveprot 0 0
# mount -o remount,nsdelegate,memory_recursiveprot /sys/fs/cgroup
# grep cgroup /proc/mounts
cgroup2 /sys/fs/cgroup cgroup2 rw,nosuid,nodev,noexec,relatime,nsdelegate,memory_recursiveprot 0 0
While a bit confusing, given that there is a way to turn off the options,
there's no reason to have the explicit "no" prefixed options. Let's remove
them.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
3942a9bd7b ("locking, rcu, cgroup: Avoid synchronize_sched() in
__cgroup_procs_write()") disabled percpu operations on threadgroup_rwsem
because the impiled synchronize_rcu() on write locking was pushing up the
latencies too much for android which constantly moves processes between
cgroups.
This makes the hotter paths - fork and exit - slower as they're always
forced into the slow path. There is no reason to force this on everyone
especially given that more common static usage pattern can now completely
avoid write-locking the rwsem. Write-locking is elided when turning on and
off controllers on empty sub-trees and CLONE_INTO_CGROUP enables seeding a
cgroup without grabbing the rwsem.
Restore the default percpu operations and introduce the mount option
"favordynmods" and config option CGROUP_FAVOR_DYNMODS for users who need
lower latencies for the dynamic operations.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Michal Koutn� <mkoutny@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Dmitry Shmidt <dimitrysh@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
We allow modifying these mount options via remount. Let's add "no" prefixed
variants so that they can be turned off too.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Michal Koutný <mkoutny@suse.com>
cgroup_update_dfl_csses() write-lock the threadgroup_rwsem as updating the
csses can trigger process migrations. However, if the subtree doesn't
contain any tasks, there aren't gonna be any cgroup migrations. This
condition can be trivially detected by testing whether
mgctx.preloaded_src_csets is empty. Elide write-locking threadgroup_rwsem if
the subtree is empty.
After this optimization, the usage pattern of creating a cgroup, enabling
the necessary controllers, and then seeding it with CLONE_INTO_CGROUP and
then removing the cgroup after it becomes empty doesn't need to write-lock
threadgroup_rwsem at all.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Michal Koutný <mkoutny@suse.com>
We have:
int cgroup_migrate_vet_dst(struct cgroup *dst_cgrp)
{
...
/* mixables don't care */
if (cgroup_is_mixable(dst_cgrp))
return 0;
/*
* If @dst_cgrp is already or can become a thread root or is
* threaded, it doesn't matter.
*/
if (cgroup_can_be_thread_root(dst_cgrp) || cgroup_is_threaded(dst_cgrp))
return 0;
...
}
but in fact the entry of cgroup_can_be_thread_root() covers case that
checking cgroup_is_mixable() as following:
static bool cgroup_can_be_thread_root(struct cgroup *cgrp)
{
/* mixables don't care */
if (cgroup_is_mixable(cgrp))
return true;
...
}
so explicitly checking in cgroup_migrate_vet_dst is unnecessary.
Signed-off-by: Lin Feng <linf@wangsu.com>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Each cset (css_set) is pinned by its tasks. When we're moving tasks around
across csets for a migration, we need to hold the source and destination
csets to ensure that they don't go away while we're moving tasks about. This
is done by linking cset->mg_preload_node on either the
mgctx->preloaded_src_csets or mgctx->preloaded_dst_csets list. Using the
same cset->mg_preload_node for both the src and dst lists was deemed okay as
a cset can't be both the source and destination at the same time.
Unfortunately, this overloading becomes problematic when multiple tasks are
involved in a migration and some of them are identity noop migrations while
others are actually moving across cgroups. For example, this can happen with
the following sequence on cgroup1:
#1> mkdir -p /sys/fs/cgroup/misc/a/b
#2> echo $$ > /sys/fs/cgroup/misc/a/cgroup.procs
#3> RUN_A_COMMAND_WHICH_CREATES_MULTIPLE_THREADS &
#4> PID=$!
#5> echo $PID > /sys/fs/cgroup/misc/a/b/tasks
#6> echo $PID > /sys/fs/cgroup/misc/a/cgroup.procs
the process including the group leader back into a. In this final migration,
non-leader threads would be doing identity migration while the group leader
is doing an actual one.
After #3, let's say the whole process was in cset A, and that after #4, the
leader moves to cset B. Then, during #6, the following happens:
1. cgroup_migrate_add_src() is called on B for the leader.
2. cgroup_migrate_add_src() is called on A for the other threads.
3. cgroup_migrate_prepare_dst() is called. It scans the src list.
4. It notices that B wants to migrate to A, so it tries to A to the dst
list but realizes that its ->mg_preload_node is already busy.
5. and then it notices A wants to migrate to A as it's an identity
migration, it culls it by list_del_init()'ing its ->mg_preload_node and
putting references accordingly.
6. The rest of migration takes place with B on the src list but nothing on
the dst list.
This means that A isn't held while migration is in progress. If all tasks
leave A before the migration finishes and the incoming task pins it, the
cset will be destroyed leading to use-after-free.
This is caused by overloading cset->mg_preload_node for both src and dst
preload lists. We wanted to exclude the cset from the src list but ended up
inadvertently excluding it from the dst list too.
This patch fixes the issue by separating out cset->mg_preload_node into
->mg_src_preload_node and ->mg_dst_preload_node, so that the src and dst
preloadings don't interfere with each other.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Mukesh Ojha <quic_mojha@quicinc.com>
Reported-by: shisiyuan <shisiyuan19870131@gmail.com>
Link: http://lkml.kernel.org/r/1654187688-27411-1-git-send-email-shisiyuan@xiaomi.com
Link: https://www.spinics.net/lists/cgroups/msg33313.html
Fixes: f817de9851 ("cgroup: prepare migration path for unified hierarchy")
Cc: stable@vger.kernel.org # v3.16+
No funtionality change, but save us some lines.
Signed-off-by: Lin Feng <linf@wangsu.com>
Acked-by: Mukesh Ojha <quic_mojha@quicinc.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Memory about struct psi_group is allocated by default for
each cgroup even if psi_disabled is true, in this case, these
allocated memory is waste, so alloc memory for struct psi_group
only when psi_disabled is false.
Signed-off-by: Chen Wandun <chenwandun@huawei.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Remove the superfluous judgment since the function is
never called for a root cgroup, as suggested by Tejun.
Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Make cgroup_debug static since it's only used in cgroup.c
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Here is the set of driver core changes for 5.18-rc1.
Not much here, primarily it was a bunch of cleanups and small updates:
- kobj_type cleanups for default_groups
- documentation updates
- firmware loader minor changes
- component common helper added and take advantage of it in many
drivers (the largest part of this pull request).
There will be a merge conflict in drivers/power/supply/ab8500_chargalg.c
with your tree, the merge conflict should be easy (take all the
changes).
All of these have been in linux-next for a while with no reported
problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here is the set of driver core changes for 5.18-rc1.
Not much here, primarily it was a bunch of cleanups and small updates:
- kobj_type cleanups for default_groups
- documentation updates
- firmware loader minor changes
- component common helper added and take advantage of it in many
drivers (the largest part of this pull request).
All of these have been in linux-next for a while with no reported
problems"
* tag 'driver-core-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (54 commits)
Documentation: update stable review cycle documentation
drivers/base/dd.c : Remove the initial value of the global variable
Documentation: update stable tree link
Documentation: add link to stable release candidate tree
devres: fix typos in comments
Documentation: add note block surrounding security patch note
samples/kobject: Use sysfs_emit instead of sprintf
base: soc: Make soc_device_match() simpler and easier to read
driver core: dd: fix return value of __setup handler
driver core: Refactor sysfs and drv/bus remove hooks
driver core: Refactor multiple copies of device cleanup
scripts: get_abi.pl: Fix typo in help message
kernfs: fix typos in comments
kernfs: remove unneeded #if 0 guard
ALSA: hda/realtek: Make use of the helper component_compare_dev_name
video: omapfb: dss: Make use of the helper component_compare_dev
power: supply: ab8500: Make use of the helper component_compare_dev
ASoC: codecs: wcd938x: Make use of the helper component_compare/release_of
iommu/mediatek: Make use of the helper component_compare/release_of
drm: of: Make use of the helper component_release_of
...
Pull cgroup updates from Tejun Heo:
"All trivial cleanups without meaningful behavior changes"
* 'for-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: cleanup comments
cgroup: Fix cgroup_can_fork() and cgroup_post_fork() kernel-doc comment
cgroup: rstat: retrieve current bstat to delta directly
cgroup: rstat: use same convention to assign cgroup_base_stat
There is no need to have struct kernfs_root be part of kernfs.h for
the whole kernel to see and poke around it. Move it internal to kernfs
code and provide a helper function, kernfs_root_to_node(), to handle the
one field that kernfs users were directly accessing from the structure.
Cc: Imran Khan <imran.f.khan@oracle.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20220222070713.3517679-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull cgroup fixes from Tejun Heo:
- Fix for a subtle bug in the recent release_agent permission check
update
- Fix for a long-standing race condition between cpuset and cpu hotplug
- Comment updates
* 'for-5.17-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cpuset: Fix kernel-doc
cgroup-v1: Correct privileges check in release_agent writes
cgroup: clarify cgroup_css_set_fork()
cgroup/cpuset: Fix a race between cpuset_attach() and cpu hotplug
With recent fixes for the permission checking when moving a task into a cgroup
using a file descriptor to a cgroup's cgroup.procs file and calling write() it
seems a good idea to clarify CLONE_INTO_CGROUP permission checking with a
comment.
Cc: Tejun Heo <tj@kernel.org>
Cc: <cgroups@vger.kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
With write operation on psi files replacing old trigger with a new one,
the lifetime of its waitqueue is totally arbitrary. Overwriting an
existing trigger causes its waitqueue to be freed and pending poll()
will stumble on trigger->event_wait which was destroyed.
Fix this by disallowing to redefine an existing psi trigger. If a write
operation is used on a file descriptor with an already existing psi
trigger, the operation will fail with EBUSY error.
Also bypass a check for psi_disabled in the psi_trigger_destroy as the
flag can be flipped after the trigger is created, leading to a memory
leak.
Fixes: 0e94682b73 ("psi: introduce psi monitor")
Reported-by: syzbot+cdb5dd11c97cc532efad@syzkaller.appspotmail.com
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Analyzed-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20220111232309.1786347-1-surenb@google.com
Add the description of @kargs in cgroup_can_fork() and
cgroup_post_fork() kernel-doc comment to remove warnings found
by running scripts/kernel-doc, which is caused by using 'make W=1'.
kernel/cgroup/cgroup.c:6235: warning: Function parameter or member
'kargs' not described in 'cgroup_can_fork'
kernel/cgroup/cgroup.c:6296: warning: Function parameter or member
'kargs' not described in 'cgroup_post_fork'
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Pull cgroup updates from Tejun Heo:
"Nothing too interesting. The only two noticeable changes are a subtle
cpuset behavior fix and trace event id field being expanded to u64
from int. Most others are code cleanups"
* 'for-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cpuset: convert 'allowed' in __cpuset_node_allowed() to be boolean
cgroup/rstat: check updated_next only for root
cgroup: rstat: explicitly put loop variant in while
cgroup: return early if it is already on preloaded list
cgroup/cpuset: Don't let child cpusets restrict parent in default hierarchy
cgroup: Trace event cgroup id fields should be u64
cgroup: fix a typo in comment
cgroup: get the wrong css for css_alloc() during cgroup_init_subsys()
cgroup: rstat: Mark benign data race to silence KCSAN
Core
----
- Defer freeing TCP skbs to the BH handler, whenever possible,
or at least perform the freeing outside of the socket lock section
to decrease cross-CPU allocator work and improve latency.
- Add netdevice refcount tracking to locate sources of netdevice
and net namespace refcount leaks.
- Make Tx watchdog less intrusive - avoid pausing Tx and restarting
all queues from a single CPU removing latency spikes.
- Various small optimizations throughout the stack from Eric Dumazet.
- Make netdev->dev_addr[] constant, force modifications to go via
appropriate helpers to allow us to keep addresses in ordered data
structures.
- Replace unix_table_lock with per-hash locks, improving performance
of bind() calls.
- Extend skb drop tracepoint with a drop reason.
- Allow SO_MARK and SO_PRIORITY setsockopt under CAP_NET_RAW.
BPF
---
- New helpers:
- bpf_find_vma(), find and inspect VMAs for profiling use cases
- bpf_loop(), runtime-bounded loop helper trading some execution
time for much faster (if at all converging) verification
- bpf_strncmp(), improve performance, avoid compiler flakiness
- bpf_get_func_arg(), bpf_get_func_ret(), bpf_get_func_arg_cnt()
for tracing programs, all inlined by the verifier
- Support BPF relocations (CO-RE) in the kernel loader.
- Further the support for BTF_TYPE_TAG annotations.
- Allow access to local storage in sleepable helpers.
- Convert verifier argument types to a composable form with different
attributes which can be shared across types (ro, maybe-null).
- Prepare libbpf for upcoming v1.0 release by cleaning up APIs,
creating new, extensible ones where missing and deprecating those
to be removed.
Protocols
---------
- WiFi (mac80211/cfg80211):
- notify user space about long "come back in N" AP responses,
allow it to react to such temporary rejections
- allow non-standard VHT MCS 10/11 rates
- use coarse time in airtime fairness code to save CPU cycles
- Bluetooth:
- rework of HCI command execution serialization to use a common
queue and work struct, and improve handling errors reported
in the middle of a batch of commands
- rework HCI event handling to use skb_pull_data, avoiding packet
parsing pitfalls
- support AOSP Bluetooth Quality Report
- SMC:
- support net namespaces, following the RDMA model
- improve connection establishment latency by pre-clearing buffers
- introduce TCP ULP for automatic redirection to SMC
- Multi-Path TCP:
- support ioctls: SIOCINQ, OUTQ, and OUTQNSD
- support socket options: IP_TOS, IP_FREEBIND, IP_TRANSPARENT,
IPV6_FREEBIND, and IPV6_TRANSPARENT, TCP_CORK and TCP_NODELAY
- support cmsgs: TCP_INQ
- improvements in the data scheduler (assigning data to subflows)
- support fastclose option (quick shutdown of the full MPTCP
connection, similar to TCP RST in regular TCP)
- MCTP (Management Component Transport) over serial, as defined by
DMTF spec DSP0253 - "MCTP Serial Transport Binding".
Driver API
----------
- Support timestamping on bond interfaces in active/passive mode.
- Introduce generic phylink link mode validation for drivers which
don't have any quirks and where MAC capability bits fully express
what's supported. Allow PCS layer to participate in the validation.
Convert a number of drivers.
- Add support to set/get size of buffers on the Rx rings and size of
the tx copybreak buffer via ethtool.
- Support offloading TC actions as first-class citizens rather than
only as attributes of filters, improve sharing and device resource
utilization.
- WiFi (mac80211/cfg80211):
- support forwarding offload (ndo_fill_forward_path)
- support for background radar detection hardware
- SA Query Procedures offload on the AP side
New hardware / drivers
----------------------
- tsnep - FPGA based TSN endpoint Ethernet MAC used in PLCs with
real-time requirements for isochronous communication with protocols
like OPC UA Pub/Sub.
- Qualcomm BAM-DMUX WWAN - driver for data channels of modems
integrated into many older Qualcomm SoCs, e.g. MSM8916 or
MSM8974 (qcom_bam_dmux).
- Microchip LAN966x multi-port Gigabit AVB/TSN Ethernet Switch
driver with support for bridging, VLANs and multicast forwarding
(lan966x).
- iwlmei driver for co-operating between Intel's WiFi driver and
Intel's Active Management Technology (AMT) devices.
- mse102x - Vertexcom MSE102x Homeplug GreenPHY chips
- Bluetooth:
- MediaTek MT7921 SDIO devices
- Foxconn MT7922A
- Realtek RTL8852AE
Drivers
-------
- Significantly improve performance in the datapaths of:
lan78xx, ax88179_178a, lantiq_xrx200, bnxt.
- Intel Ethernet NICs:
- igb: support PTP/time PEROUT and EXTTS SDP functions on
82580/i354/i350 adapters
- ixgbevf: new PF -> VF mailbox API which avoids the risk of
mailbox corruption with ESXi
- iavf: support configuration of VLAN features of finer granularity,
stacked tags and filtering
- ice: PTP support for new E822 devices with sub-ns precision
- ice: support firmware activation without reboot
- Mellanox Ethernet NICs (mlx5):
- expose control over IRQ coalescing mode (CQE vs EQE) via ethtool
- support TC forwarding when tunnel encap and decap happen between
two ports of the same NIC
- dynamically size and allow disabling various features to save
resources for running in embedded / SmartNIC scenarios
- Broadcom Ethernet NICs (bnxt):
- use page frag allocator to improve Rx performance
- expose control over IRQ coalescing mode (CQE vs EQE) via ethtool
- Other Ethernet NICs:
- amd-xgbe: add Ryzen 6000 (Yellow Carp) Ethernet support
- Microsoft cloud/virtual NIC (mana):
- add XDP support (PASS, DROP, TX)
- Mellanox Ethernet switches (mlxsw):
- initial support for Spectrum-4 ASICs
- VxLAN with IPv6 underlay
- Marvell Ethernet switches (prestera):
- support flower flow templates
- add basic IP forwarding support
- NXP embedded Ethernet switches (ocelot & felix):
- support Per-Stream Filtering and Policing (PSFP)
- enable cut-through forwarding between ports by default
- support FDMA to improve packet Rx/Tx to CPU
- Other embedded switches:
- hellcreek: improve trapping management (STP and PTP) packets
- qca8k: support link aggregation and port mirroring
- Qualcomm 802.11ax WiFi (ath11k):
- qca6390, wcn6855: enable 802.11 power save mode in station mode
- BSS color change support
- WCN6855 hw2.1 support
- 11d scan offload support
- scan MAC address randomization support
- full monitor mode, only supported on QCN9074
- qca6390/wcn6855: report signal and tx bitrate
- qca6390: rfkill support
- qca6390/wcn6855: regdb.bin support
- Intel WiFi (iwlwifi):
- support SAR GEO Offset Mapping (SGOM) and Time-Aware-SAR (TAS)
in cooperation with the BIOS
- support for Optimized Connectivity Experience (OCE) scan
- support firmware API version 68
- lots of preparatory work for the upcoming Bz device family
- MediaTek WiFi (mt76):
- Specific Absorption Rate (SAR) support
- mt7921: 160 MHz channel support
- RealTek WiFi (rtw88):
- Specific Absorption Rate (SAR) support
- scan offload
- Other WiFi NICs
- ath10k: support fetching (pre-)calibration data from nvmem
- brcmfmac: configure keep-alive packet on suspend
- wcn36xx: beacon filter support
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag '5.17-net-next' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from Jakub Kicinski:
"Core
----
- Defer freeing TCP skbs to the BH handler, whenever possible, or at
least perform the freeing outside of the socket lock section to
decrease cross-CPU allocator work and improve latency.
- Add netdevice refcount tracking to locate sources of netdevice and
net namespace refcount leaks.
- Make Tx watchdog less intrusive - avoid pausing Tx and restarting
all queues from a single CPU removing latency spikes.
- Various small optimizations throughout the stack from Eric Dumazet.
- Make netdev->dev_addr[] constant, force modifications to go via
appropriate helpers to allow us to keep addresses in ordered data
structures.
- Replace unix_table_lock with per-hash locks, improving performance
of bind() calls.
- Extend skb drop tracepoint with a drop reason.
- Allow SO_MARK and SO_PRIORITY setsockopt under CAP_NET_RAW.
BPF
---
- New helpers:
- bpf_find_vma(), find and inspect VMAs for profiling use cases
- bpf_loop(), runtime-bounded loop helper trading some execution
time for much faster (if at all converging) verification
- bpf_strncmp(), improve performance, avoid compiler flakiness
- bpf_get_func_arg(), bpf_get_func_ret(), bpf_get_func_arg_cnt()
for tracing programs, all inlined by the verifier
- Support BPF relocations (CO-RE) in the kernel loader.
- Further the support for BTF_TYPE_TAG annotations.
- Allow access to local storage in sleepable helpers.
- Convert verifier argument types to a composable form with different
attributes which can be shared across types (ro, maybe-null).
- Prepare libbpf for upcoming v1.0 release by cleaning up APIs,
creating new, extensible ones where missing and deprecating those
to be removed.
Protocols
---------
- WiFi (mac80211/cfg80211):
- notify user space about long "come back in N" AP responses,
allow it to react to such temporary rejections
- allow non-standard VHT MCS 10/11 rates
- use coarse time in airtime fairness code to save CPU cycles
- Bluetooth:
- rework of HCI command execution serialization to use a common
queue and work struct, and improve handling errors reported in
the middle of a batch of commands
- rework HCI event handling to use skb_pull_data, avoiding packet
parsing pitfalls
- support AOSP Bluetooth Quality Report
- SMC:
- support net namespaces, following the RDMA model
- improve connection establishment latency by pre-clearing buffers
- introduce TCP ULP for automatic redirection to SMC
- Multi-Path TCP:
- support ioctls: SIOCINQ, OUTQ, and OUTQNSD
- support socket options: IP_TOS, IP_FREEBIND, IP_TRANSPARENT,
IPV6_FREEBIND, and IPV6_TRANSPARENT, TCP_CORK and TCP_NODELAY
- support cmsgs: TCP_INQ
- improvements in the data scheduler (assigning data to subflows)
- support fastclose option (quick shutdown of the full MPTCP
connection, similar to TCP RST in regular TCP)
- MCTP (Management Component Transport) over serial, as defined by
DMTF spec DSP0253 - "MCTP Serial Transport Binding".
Driver API
----------
- Support timestamping on bond interfaces in active/passive mode.
- Introduce generic phylink link mode validation for drivers which
don't have any quirks and where MAC capability bits fully express
what's supported. Allow PCS layer to participate in the validation.
Convert a number of drivers.
- Add support to set/get size of buffers on the Rx rings and size of
the tx copybreak buffer via ethtool.
- Support offloading TC actions as first-class citizens rather than
only as attributes of filters, improve sharing and device resource
utilization.
- WiFi (mac80211/cfg80211):
- support forwarding offload (ndo_fill_forward_path)
- support for background radar detection hardware
- SA Query Procedures offload on the AP side
New hardware / drivers
----------------------
- tsnep - FPGA based TSN endpoint Ethernet MAC used in PLCs with
real-time requirements for isochronous communication with protocols
like OPC UA Pub/Sub.
- Qualcomm BAM-DMUX WWAN - driver for data channels of modems
integrated into many older Qualcomm SoCs, e.g. MSM8916 or MSM8974
(qcom_bam_dmux).
- Microchip LAN966x multi-port Gigabit AVB/TSN Ethernet Switch driver
with support for bridging, VLANs and multicast forwarding
(lan966x).
- iwlmei driver for co-operating between Intel's WiFi driver and
Intel's Active Management Technology (AMT) devices.
- mse102x - Vertexcom MSE102x Homeplug GreenPHY chips
- Bluetooth:
- MediaTek MT7921 SDIO devices
- Foxconn MT7922A
- Realtek RTL8852AE
Drivers
-------
- Significantly improve performance in the datapaths of: lan78xx,
ax88179_178a, lantiq_xrx200, bnxt.
- Intel Ethernet NICs:
- igb: support PTP/time PEROUT and EXTTS SDP functions on
82580/i354/i350 adapters
- ixgbevf: new PF -> VF mailbox API which avoids the risk of
mailbox corruption with ESXi
- iavf: support configuration of VLAN features of finer
granularity, stacked tags and filtering
- ice: PTP support for new E822 devices with sub-ns precision
- ice: support firmware activation without reboot
- Mellanox Ethernet NICs (mlx5):
- expose control over IRQ coalescing mode (CQE vs EQE) via ethtool
- support TC forwarding when tunnel encap and decap happen between
two ports of the same NIC
- dynamically size and allow disabling various features to save
resources for running in embedded / SmartNIC scenarios
- Broadcom Ethernet NICs (bnxt):
- use page frag allocator to improve Rx performance
- expose control over IRQ coalescing mode (CQE vs EQE) via ethtool
- Other Ethernet NICs:
- amd-xgbe: add Ryzen 6000 (Yellow Carp) Ethernet support
- Microsoft cloud/virtual NIC (mana):
- add XDP support (PASS, DROP, TX)
- Mellanox Ethernet switches (mlxsw):
- initial support for Spectrum-4 ASICs
- VxLAN with IPv6 underlay
- Marvell Ethernet switches (prestera):
- support flower flow templates
- add basic IP forwarding support
- NXP embedded Ethernet switches (ocelot & felix):
- support Per-Stream Filtering and Policing (PSFP)
- enable cut-through forwarding between ports by default
- support FDMA to improve packet Rx/Tx to CPU
- Other embedded switches:
- hellcreek: improve trapping management (STP and PTP) packets
- qca8k: support link aggregation and port mirroring
- Qualcomm 802.11ax WiFi (ath11k):
- qca6390, wcn6855: enable 802.11 power save mode in station mode
- BSS color change support
- WCN6855 hw2.1 support
- 11d scan offload support
- scan MAC address randomization support
- full monitor mode, only supported on QCN9074
- qca6390/wcn6855: report signal and tx bitrate
- qca6390: rfkill support
- qca6390/wcn6855: regdb.bin support
- Intel WiFi (iwlwifi):
- support SAR GEO Offset Mapping (SGOM) and Time-Aware-SAR (TAS)
in cooperation with the BIOS
- support for Optimized Connectivity Experience (OCE) scan
- support firmware API version 68
- lots of preparatory work for the upcoming Bz device family
- MediaTek WiFi (mt76):
- Specific Absorption Rate (SAR) support
- mt7921: 160 MHz channel support
- RealTek WiFi (rtw88):
- Specific Absorption Rate (SAR) support
- scan offload
- Other WiFi NICs
- ath10k: support fetching (pre-)calibration data from nvmem
- brcmfmac: configure keep-alive packet on suspend
- wcn36xx: beacon filter support"
* tag '5.17-net-next' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2048 commits)
tcp: tcp_send_challenge_ack delete useless param `skb`
net/qla3xxx: Remove useless DMA-32 fallback configuration
rocker: Remove useless DMA-32 fallback configuration
hinic: Remove useless DMA-32 fallback configuration
lan743x: Remove useless DMA-32 fallback configuration
net: enetc: Remove useless DMA-32 fallback configuration
cxgb4vf: Remove useless DMA-32 fallback configuration
cxgb4: Remove useless DMA-32 fallback configuration
cxgb3: Remove useless DMA-32 fallback configuration
bnx2x: Remove useless DMA-32 fallback configuration
et131x: Remove useless DMA-32 fallback configuration
be2net: Remove useless DMA-32 fallback configuration
vmxnet3: Remove useless DMA-32 fallback configuration
bna: Simplify DMA setting
net: alteon: Simplify DMA setting
myri10ge: Simplify DMA setting
qlcnic: Simplify DMA setting
net: allwinner: Fix print format
page_pool: remove spinlock in page_pool_refill_alloc_cache()
amt: fix wrong return type of amt_send_membership_update()
...
cgroup process migration permission checks are performed at write time as
whether a given operation is allowed or not is dependent on the content of
the write - the PID. This currently uses current's cgroup namespace which is
a potential security weakness as it may allow scenarios where a less
privileged process tricks a more privileged one into writing into a fd that
it created.
This patch makes cgroup remember the cgroup namespace at the time of open
and uses it for migration permission checks instad of current's. Note that
this only applies to cgroup2 as cgroup1 doesn't have namespace support.
This also fixes a use-after-free bug on cgroupns reported in
https://lore.kernel.org/r/00000000000048c15c05d0083397@google.com
Note that backporting this fix also requires the preceding patch.
Reported-by: "Eric W. Biederman" <ebiederm@xmission.com>
Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Cc: Michal Koutný <mkoutny@suse.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Reported-by: syzbot+50f5cf33a284ce738b62@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/00000000000048c15c05d0083397@google.com
Fixes: 5136f6365c ("cgroup: implement "nsdelegate" mount option")
Signed-off-by: Tejun Heo <tj@kernel.org>
of->priv is currently used by each interface file implementation to store
private information. This patch collects the current two private data usages
into struct cgroup_file_ctx which is allocated and freed by the common path.
This allows generic private data which applies to multiple files, which will
be used to in the following patch.
Note that cgroup_procs iterator is now embedded as procs.iter in the new
cgroup_file_ctx so that it doesn't need to be allocated and freed
separately.
v2: union dropped from cgroup_file_ctx and the procs iterator is embedded in
cgroup_file_ctx as suggested by Linus.
v3: Michal pointed out that cgroup1's procs pidlist uses of->priv too.
Converted. Didn't change to embedded allocation as cgroup1 pidlists get
stored for caching.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
cgroup process migration permission checks are performed at write time as
whether a given operation is allowed or not is dependent on the content of
the write - the PID. This currently uses current's credentials which is a
potential security weakness as it may allow scenarios where a less
privileged process tricks a more privileged one into writing into a fd that
it created.
This patch makes both cgroup2 and cgroup1 process migration interfaces to
use the credentials saved at the time of open (file->f_cred) instead of
current's.
Reported-by: "Eric W. Biederman" <ebiederm@xmission.com>
Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Fixes: 187fe84067 ("cgroup: require write perm on common ancestor when moving processes on the default hierarchy")
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
We're about to break the cgroup-defs.h -> bpf-cgroup.h dependency,
make sure those who actually need more than the definition of
struct cgroup_bpf include bpf-cgroup.h explicitly.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/bpf/20211216025538.1649516-3-kuba@kernel.org
If a cset is already on preloaded list, this means we have already setup
this cset properly for migration.
This patch just relocates the root cgrp lookup which isn't used anyway
when the cset is already on the preloaded list.
[tj@kernel.org: rephrase the commit log]
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
css_alloc() needs the parent css, while cgroup_css() gets current
cgropu's css. So we are getting the wrong css during
cgroup_init_subsys().
Fortunately, cgrp_dfl_root.cgrp's css is not set yet, so the value we
pass to css_alloc() is NULL anyway.
Let's pass NULL directly during init, since we know there is no parent
yet.
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Pull cgroup updates from Tejun Heo:
- The misc controller now reports allocation rejections through
misc.events instead of printking
- cgroup_mutex usage is reduced to improve scalability of some
operations
- vhost helper threads are now assigned to the right cgroup on cgroup2
- Bug fixes
* 'for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: bpf: Move wrapper for __cgroup_bpf_*() to kernel/bpf/cgroup.c
cgroup: Fix rootcg cpu.stat guest double counting
cgroup: no need for cgroup_mutex for /proc/cgroups
cgroup: remove cgroup_mutex from cgroupstats_build
cgroup: reduce dependency on cgroup_mutex
cgroup: cgroup-v1: do not exclude cgrp_dfl_root
cgroup: Make rebind_subsystems() disable v2 controllers all at once
docs/cgroup: add entry for misc.events
misc_cgroup: remove error log to avoid log flood
misc_cgroup: introduce misc.events to count failures
In commit 324bda9e6c5a("bpf: multi program support for cgroup+bpf")
cgroup_bpf_*() called from kernel/bpf/syscall.c, but now they are only
used in kernel/bpf/cgroup.c, so move these function to
kernel/bpf/cgroup.c, like cgroup_bpf_replace().
Signed-off-by: He Fengqing <hefengqing@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Currently cgroup_get_from_path() and cgroup_get_from_id() grab
cgroup_mutex before traversing the default hierarchy to find the
kernfs_node corresponding to the path/id and then extract the linked
cgroup. Since cgroup_mutex is still held, it is guaranteed that the
cgroup will be alive and the reference can be taken on it.
However similar guarantee can be provided without depending on the
cgroup_mutex and potentially reducing avenues of cgroup_mutex contentions.
The kernfs_node's priv pointer is RCU protected pointer and with just
rcu read lock we can grab the reference on the cgroup without
cgroup_mutex. So, remove cgroup_mutex from them.
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
When enabling CONFIG_CGROUP_BPF, kmemleak can be observed by running
the command as below:
$mount -t cgroup -o none,name=foo cgroup cgroup/
$umount cgroup/
unreferenced object 0xc3585c40 (size 64):
comm "mount", pid 425, jiffies 4294959825 (age 31.990s)
hex dump (first 32 bytes):
01 00 00 80 84 8c 28 c0 00 00 00 00 00 00 00 00 ......(.........
00 00 00 00 00 00 00 00 6c 43 a0 c3 00 00 00 00 ........lC......
backtrace:
[<e95a2f9e>] cgroup_bpf_inherit+0x44/0x24c
[<1f03679c>] cgroup_setup_root+0x174/0x37c
[<ed4b0ac5>] cgroup1_get_tree+0x2c0/0x4a0
[<f85b12fd>] vfs_get_tree+0x24/0x108
[<f55aec5c>] path_mount+0x384/0x988
[<e2d5e9cd>] do_mount+0x64/0x9c
[<208c9cfe>] sys_mount+0xfc/0x1f4
[<06dd06e0>] ret_fast_syscall+0x0/0x48
[<a8308cb3>] 0xbeb4daa8
This is because that since the commit 2b0d3d3e4f ("percpu_ref: reduce
memory footprint of percpu_ref in fast path") root_cgrp->bpf.refcnt.data
is allocated by the function percpu_ref_init in cgroup_bpf_inherit which
is called by cgroup_setup_root when mounting, but not freed along with
root_cgrp when umounting. Adding cgroup_bpf_offline which calls
percpu_ref_kill to cgroup_kill_sb can free root_cgrp->bpf.refcnt.data in
umount path.
This patch also fixes the commit 4bfc0bb2c6 ("bpf: decouple the lifetime
of cgroup_bpf from cgroup itself"). A cgroup_bpf_offline is needed to do a
cleanup that frees the resources which are allocated by cgroup_bpf_inherit
in cgroup_setup_root.
And inside cgroup_bpf_offline, cgroup_get() is at the beginning and
cgroup_put is at the end of cgroup_bpf_release which is called by
cgroup_bpf_offline. So cgroup_bpf_offline can keep the balance of
cgroup's refcount.
Fixes: 2b0d3d3e4f ("percpu_ref: reduce memory footprint of percpu_ref in fast path")
Fixes: 4bfc0bb2c6 ("bpf: decouple the lifetime of cgroup_bpf from cgroup itself")
Signed-off-by: Quanyang Wang <quanyang.wang@windriver.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Roman Gushchin <guro@fb.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20211018075623.26884-1-quanyang.wang@windriver.com
If cgroup_sk_alloc() is called from interrupt context, then just assign the
root cgroup to skcd->cgroup. Prior to commit 8520e224f5 ("bpf, cgroups:
Fix cgroup v2 fallback on v1/v2 mixed mode") we would just return, and later
on in sock_cgroup_ptr(), we were NULL-testing the cgroup in fast-path, and
iff indeed NULL returning the root cgroup (v ?: &cgrp_dfl_root.cgrp). Rather
than re-adding the NULL-test to the fast-path we can just assign it once from
cgroup_sk_alloc() given v1/v2 handling has been simplified. The migration from
NULL test with returning &cgrp_dfl_root.cgrp to assigning &cgrp_dfl_root.cgrp
directly does /not/ change behavior for callers of sock_cgroup_ptr().
syzkaller was able to trigger a splat in the legacy netrom code base, where
the RX handler in nr_rx_frame() calls nr_make_new() which calls sk_alloc()
and therefore cgroup_sk_alloc() with in_interrupt() condition. Thus the NULL
skcd->cgroup, where it trips over on cgroup_sk_free() side given it expects
a non-NULL object. There are a few other candidates aside from netrom which
have similar pattern where in their accept-like implementation, they just call
to sk_alloc() and thus cgroup_sk_alloc() instead of sk_clone_lock() with the
corresponding cgroup_sk_clone() which then inherits the cgroup from the parent
socket. None of them are related to core protocols where BPF cgroup programs
are running from. However, in future, they should follow to implement a similar
inheritance mechanism.
Additionally, with a !CONFIG_CGROUP_NET_PRIO and !CONFIG_CGROUP_NET_CLASSID
configuration, the same issue was exposed also prior to 8520e224f5 due to
commit e876ecc67d ("cgroup: memcg: net: do not associate sock with unrelated
cgroup") which added the early in_interrupt() return back then.
Fixes: 8520e224f5 ("bpf, cgroups: Fix cgroup v2 fallback on v1/v2 mixed mode")
Fixes: e876ecc67d ("cgroup: memcg: net: do not associate sock with unrelated cgroup")
Reported-by: syzbot+df709157a4ecaf192b03@syzkaller.appspotmail.com
Reported-by: syzbot+533f389d4026d86a2a95@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: syzbot+df709157a4ecaf192b03@syzkaller.appspotmail.com
Tested-by: syzbot+533f389d4026d86a2a95@syzkaller.appspotmail.com
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/bpf/20210927123921.21535-1-daniel@iogearbox.net
It was found that the following warning was displayed when remounting
controllers from cgroup v2 to v1:
[ 8042.997778] WARNING: CPU: 88 PID: 80682 at kernel/cgroup/cgroup.c:3130 cgroup_apply_control_disable+0x158/0x190
:
[ 8043.091109] RIP: 0010:cgroup_apply_control_disable+0x158/0x190
[ 8043.096946] Code: ff f6 45 54 01 74 39 48 8d 7d 10 48 c7 c6 e0 46 5a a4 e8 7b 67 33 00 e9 41 ff ff ff 49 8b 84 24 e8 01 00 00 0f b7 40 08 eb 95 <0f> 0b e9 5f ff ff ff 48 83 c4 08 5b 5d 41 5c 41 5d 41 5e 41 5f c3
[ 8043.115692] RSP: 0018:ffffba8a47c23d28 EFLAGS: 00010202
[ 8043.120916] RAX: 0000000000000036 RBX: ffffffffa624ce40 RCX: 000000000000181a
[ 8043.128047] RDX: ffffffffa63c43e0 RSI: ffffffffa63c43e0 RDI: ffff9d7284ee1000
[ 8043.135180] RBP: ffff9d72874c5800 R08: ffffffffa624b090 R09: 0000000000000004
[ 8043.142314] R10: ffffffffa624b080 R11: 0000000000002000 R12: ffff9d7284ee1000
[ 8043.149447] R13: ffff9d7284ee1000 R14: ffffffffa624ce70 R15: ffffffffa6269e20
[ 8043.156576] FS: 00007f7747cff740(0000) GS:ffff9d7a5fc00000(0000) knlGS:0000000000000000
[ 8043.164663] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 8043.170409] CR2: 00007f7747e96680 CR3: 0000000887d60001 CR4: 00000000007706e0
[ 8043.177539] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 8043.184673] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 8043.191804] PKRU: 55555554
[ 8043.194517] Call Trace:
[ 8043.196970] rebind_subsystems+0x18c/0x470
[ 8043.201070] cgroup_setup_root+0x16c/0x2f0
[ 8043.205177] cgroup1_root_to_use+0x204/0x2a0
[ 8043.209456] cgroup1_get_tree+0x3e/0x120
[ 8043.213384] vfs_get_tree+0x22/0xb0
[ 8043.216883] do_new_mount+0x176/0x2d0
[ 8043.220550] __x64_sys_mount+0x103/0x140
[ 8043.224474] do_syscall_64+0x38/0x90
[ 8043.228063] entry_SYSCALL_64_after_hwframe+0x44/0xae
It was caused by the fact that rebind_subsystem() disables
controllers to be rebound one by one. If more than one disabled
controllers are originally from the default hierarchy, it means that
cgroup_apply_control_disable() will be called multiple times for the
same default hierarchy. A controller may be killed by css_kill() in
the first round. In the second round, the killed controller may not be
completely dead yet leading to the warning.
To avoid this problem, we collect all the ssid's of controllers that
needed to be disabled from the default hierarchy and then disable them
in one go instead of one by one.
Fixes: 334c3679ec ("cgroup: reimplement rebind_subsystems() using cgroup_apply_control() and friends")
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Fix cgroup v1 interference when non-root cgroup v2 BPF programs are used.
Back in the days, commit bd1060a1d6 ("sock, cgroup: add sock->sk_cgroup")
embedded per-socket cgroup information into sock->sk_cgrp_data and in order
to save 8 bytes in struct sock made both mutually exclusive, that is, when
cgroup v1 socket tagging (e.g. net_cls/net_prio) is used, then cgroup v2
falls back to the root cgroup in sock_cgroup_ptr() (&cgrp_dfl_root.cgrp).
The assumption made was "there is no reason to mix the two and this is in line
with how legacy and v2 compatibility is handled" as stated in bd1060a1d6.
However, with Kubernetes more widely supporting cgroups v2 as well nowadays,
this assumption no longer holds, and the possibility of the v1/v2 mixed mode
with the v2 root fallback being hit becomes a real security issue.
Many of the cgroup v2 BPF programs are also used for policy enforcement, just
to pick _one_ example, that is, to programmatically deny socket related system
calls like connect(2) or bind(2). A v2 root fallback would implicitly cause
a policy bypass for the affected Pods.
In production environments, we have recently seen this case due to various
circumstances: i) a different 3rd party agent and/or ii) a container runtime
such as [0] in the user's environment configuring legacy cgroup v1 net_cls
tags, which triggered implicitly mentioned root fallback. Another case is
Kubernetes projects like kind [1] which create Kubernetes nodes in a container
and also add cgroup namespaces to the mix, meaning programs which are attached
to the cgroup v2 root of the cgroup namespace get attached to a non-root
cgroup v2 path from init namespace point of view. And the latter's root is
out of reach for agents on a kind Kubernetes node to configure. Meaning, any
entity on the node setting cgroup v1 net_cls tag will trigger the bypass
despite cgroup v2 BPF programs attached to the namespace root.
Generally, this mutual exclusiveness does not hold anymore in today's user
environments and makes cgroup v2 usage from BPF side fragile and unreliable.
This fix adds proper struct cgroup pointer for the cgroup v2 case to struct
sock_cgroup_data in order to address these issues; this implicitly also fixes
the tradeoffs being made back then with regards to races and refcount leaks
as stated in bd1060a1d6, and removes the fallback, so that cgroup v2 BPF
programs always operate as expected.
[0] https://github.com/nestybox/sysbox/
[1] https://kind.sigs.k8s.io/
Fixes: bd1060a1d6 ("sock, cgroup: add sock->sk_cgroup")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/bpf/20210913230759.2313-1-daniel@iogearbox.net
As done before in commit cb4a316752 ("cgroup: use bitmask to filter
for_each_subsys"), avoid compiler warnings for the pathological case of
having no subsystems (i.e. CGROUP_SUBSYS_COUNT == 0). This condition is
hit for the arm multi_v7_defconfig config under -Wzero-length-bounds:
In file included from ./arch/arm/include/generated/asm/rwonce.h:1,
from include/linux/compiler.h:264,
from include/uapi/linux/swab.h:6,
from include/linux/swab.h:5,
from arch/arm/include/asm/opcodes.h:86,
from arch/arm/include/asm/bug.h:7,
from include/linux/bug.h:5,
from include/linux/thread_info.h:13,
from include/asm-generic/current.h:5,
from ./arch/arm/include/generated/asm/current.h:1,
from include/linux/sched.h:12,
from include/linux/cgroup.h:12,
from kernel/cgroup/cgroup-internal.h:5,
from kernel/cgroup/cgroup.c:31:
kernel/cgroup/cgroup.c: In function 'of_css':
kernel/cgroup/cgroup.c:651:42: warning: array subscript '<unknown>' is outside the bounds of an
interior zero-length array 'struct cgroup_subsys_state *[0]' [-Wzero-length-bounds]
651 | return rcu_dereference_raw(cgrp->subsys[cft->ss->id]);
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Tejun Heo <tj@kernel.org>
Cc: Zefan Li <lizefan.x@bytedance.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: cgroups@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Git rid of an outdated comment.
Since cgroup was fully switched to fs_context, cgroup_mount() is gone and
it's confusing to mention in comments of cgroup_kill_sb(). Delete it.
Signed-off-by: zhaoxiaoqiang11 <zhaoxiaoqiang11@jd.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This series consists of the usual driver updates (ufs, ibmvfc,
megaraid_sas, lpfc, elx, mpi3mr, qedi, iscsi, storvsc, mpt3sas) with
elx and mpi3mr being new drivers. The major core change is a rework
to drop the status byte handling macros and the old bit shifted
definitions and the rest of the updates are minor fixes.
Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI updates from James Bottomley:
"This series consists of the usual driver updates (ufs, ibmvfc,
megaraid_sas, lpfc, elx, mpi3mr, qedi, iscsi, storvsc, mpt3sas) with
elx and mpi3mr being new drivers.
The major core change is a rework to drop the status byte handling
macros and the old bit shifted definitions and the rest of the updates
are minor fixes"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (287 commits)
scsi: aha1740: Avoid over-read of sense buffer
scsi: arcmsr: Avoid over-read of sense buffer
scsi: ips: Avoid over-read of sense buffer
scsi: ufs: ufs-mediatek: Add missing of_node_put() in ufs_mtk_probe()
scsi: elx: libefc: Fix IRQ restore in efc_domain_dispatch_frame()
scsi: elx: libefc: Fix less than zero comparison of a unsigned int
scsi: elx: efct: Fix pointer error checking in debugfs init
scsi: elx: efct: Fix is_originator return code type
scsi: elx: efct: Fix link error for _bad_cmpxchg
scsi: elx: efct: Eliminate unnecessary boolean check in efct_hw_command_cancel()
scsi: elx: efct: Do not use id uninitialized in efct_lio_setup_session()
scsi: elx: efct: Fix error handling in efct_hw_init()
scsi: elx: efct: Remove redundant initialization of variable lun
scsi: elx: efct: Fix spelling mistake "Unexected" -> "Unexpected"
scsi: lpfc: Fix build error in lpfc_scsi.c
scsi: target: iscsi: Remove redundant continue statement
scsi: qla4xxx: Remove redundant continue statement
scsi: ppa: Switch to use module_parport_driver()
scsi: imm: Switch to use module_parport_driver()
scsi: mpt3sas: Fix error return value in _scsih_expander_add()
...
Pull cgroup updates from Tejun Heo:
- cgroup.kill is added which implements atomic killing of the whole
subtree.
Down the line, this should be able to replace the multiple userland
implementations of "keep killing till empty".
- PSI can now be turned off at boot time to avoid overhead for
configurations which don't care about PSI.
* 'for-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: make per-cgroup pressure stall tracking configurable
cgroup: Fix kernel-doc
cgroup: inline cgroup_task_freeze()
tests/cgroup: test cgroup.kill
tests/cgroup: move cg_wait_for(), cg_prepare_for_wait()
tests/cgroup: use cgroup.kill in cg_killall()
docs/cgroup: add entry for cgroup.kill
cgroup: introduce cgroup.kill
The current code only associates with the existing blkcg when aio is used
to access the backing file. This patch covers all types of i/o to the
backing file and also associates the memcg so if the backing file is on
tmpfs, memory is charged appropriately.
This patch also exports cgroup_get_e_css and int_active_memcg so it can be
used by the loop module.
Link: https://lkml.kernel.org/r/20210610173944.1203706-4-schatzberg.dan@gmail.com
Signed-off-by: Dan Schatzberg <schatzberg.dan@gmail.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Jens Axboe <axboe@kernel.dk>
Cc: Chris Down <chris@chrisdown.name>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a new function, cgroup_get_from_id(), to retrieve the cgroup associated
with a cgroup id. Also export the function cgroup_get_e_css() as this is
needed in blk-cgroup.h.
Link: https://lore.kernel.org/r/20210608043556.274139-2-muneendra.kumar@broadcom.com
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Muneendra Kumar <muneendra.kumar@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
PSI accounts stalls for each cgroup separately and aggregates it at each
level of the hierarchy. This causes additional overhead with psi_avgs_work
being called for each cgroup in the hierarchy. psi_avgs_work has been
highly optimized, however on systems with large number of cgroups the
overhead becomes noticeable.
Systems which use PSI only at the system level could avoid this overhead
if PSI can be configured to skip per-cgroup stall accounting.
Add "cgroup_disable=pressure" kernel command-line option to allow
requesting system-wide only pressure stall accounting. When set, it
keeps system-wide accounting under /proc/pressure/ but skips accounting
for individual cgroups and does not expose PSI nodes in cgroup hierarchy.
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Fix function name in cgroup.c and rstat.c kernel-doc comment
to remove these warnings found by clang_w1.
kernel/cgroup/cgroup.c:2401: warning: expecting prototype for
cgroup_taskset_migrate(). Prototype was for cgroup_migrate_execute()
instead.
kernel/cgroup/rstat.c:233: warning: expecting prototype for
cgroup_rstat_flush_begin(). Prototype was for cgroup_rstat_flush_hold()
instead.
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Fixes: 'commit e595cd7069 ("cgroup: track migration context in cgroup_mgctx")'
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Fix some spelling mistakes in comments:
hierarhcy ==> hierarchy
automtically ==> automatically
overriden ==> overridden
In absense of .. or ==> In absence of .. and
assocaited ==> associated
taget ==> target
initate ==> initiate
succeded ==> succeeded
curremt ==> current
udpated ==> updated
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This patch effectively reverts the commit a3e72739b7 ("cgroup: fix
too early usage of static_branch_disable()"). The commit 6041186a32
("init: initialize jump labels before command line option parsing") has
moved the jump_label_init() before parse_args() which has made the
commit a3e72739b7 unnecessary. On the other hand there are
consequences of disabling the controllers later as there are subsystems
doing the controller checks for different decisions. One such incident
is reported [1] regarding the memory controller and its impact on memory
reclaim code.
[1] https://lore.kernel.org/linux-mm/921e53f3-4b13-aab8-4a9e-e83ff15371e4@nec.com
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Reported-by: NOMURA JUNICHI(野村 淳一) <junichi.nomura@nec.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Tested-by: Jun'ichi Nomura <junichi.nomura@nec.com>
After the introduction of the cgroup.kill there is only one call site
of cgroup_task_freeze() left: cgroup_exit(). cgroup_task_freeze() is
currently taking rcu_read_lock() to read task's cgroup flags, but
because it's always called with css_set_lock locked, the rcu protection
is excessive.
Simplify the code by inlining cgroup_task_freeze().
v2: fix build
Signed-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Introduce the cgroup.kill file. It does what it says on the tin and
allows a caller to kill a cgroup by writing "1" into cgroup.kill.
The file is available in non-root cgroups.
Killing cgroups is a process directed operation, i.e. the whole
thread-group is affected. Consequently trying to write to cgroup.kill in
threaded cgroups will be rejected and EOPNOTSUPP returned. This behavior
aligns with cgroup.procs where reads in threaded-cgroups are rejected
with EOPNOTSUPP.
The cgroup.kill file is write-only since killing a cgroup is an event
not which makes it different from e.g. freezer where a cgroup
transitions between the two states.
As with all new cgroup features cgroup.kill is recursive by default.
Killing a cgroup is protected against concurrent migrations through the
cgroup mutex. To protect against forkbombs and to mitigate the effect of
racing forks a new CGRP_KILL css set lock protected flag is introduced
that is set prior to killing a cgroup and unset after the cgroup has
been killed. We can then check in cgroup_post_fork() where we hold the
css set lock already whether the cgroup is currently being killed. If so
we send the child a SIGKILL signal immediately taking it down as soon as
it returns to userspace. To make the killing of the child semantically
clean it is killed after all cgroup attachment operations have been
finalized.
There are various use-cases of this interface:
- Containers usually have a conservative layout where each container
usually has a delegated cgroup. For such layouts there is a 1:1
mapping between container and cgroup. If the container in addition
uses a separate pid namespace then killing a container usually becomes
a simple kill -9 <container-init-pid> from an ancestor pid namespace.
However, there are quite a few scenarios where that isn't true. For
example, there are containers that share the cgroup with other
processes on purpose that are supposed to be bound to the lifetime of
the container but are not in the same pidns of the container.
Containers that are in a delegated cgroup but share the pid namespace
with the host or other containers.
- Service managers such as systemd use cgroups to group and organize
processes belonging to a service. They usually rely on a recursive
algorithm now to kill a service. With cgroup.kill this becomes a
simple write to cgroup.kill.
- Userspace OOM implementations can make good use of this feature to
efficiently take down whole cgroups quickly.
- The kill program can gain a new
kill --cgroup /sys/fs/cgroup/delegated
flag to take down cgroups.
A few observations about the semantics:
- If parent and child are in the same cgroup and CLONE_INTO_CGROUP is
not specified we are not taking cgroup mutex meaning the cgroup can be
killed while a process in that cgroup is forking.
If the kill request happens right before cgroup_can_fork() and before
the parent grabs its siglock the parent is guaranteed to see the
pending SIGKILL. In addition we perform another check in
cgroup_post_fork() whether the cgroup is being killed and is so take
down the child (see above). This is robust enough and protects gainst
forkbombs. If userspace really really wants to have stricter
protection the simple solution would be to grab the write side of the
cgroup threadgroup rwsem which will force all ongoing forks to
complete before killing starts. We concluded that this is not
necessary as the semantics for concurrent forking should simply align
with freezer where a similar check as cgroup_post_fork() is performed.
For all other cases CLONE_INTO_CGROUP is required. In this case we
will grab the cgroup mutex so the cgroup can't be killed while we
fork. Once we're done with the fork and have dropped cgroup mutex we
are visible and will be found by any subsequent kill request.
- We obviously don't kill kthreads. This means a cgroup that has a
kthread will not become empty after killing and consequently no
unpopulated event will be generated. The assumption is that kthreads
should be in the root cgroup only anyway so this is not an issue.
- We skip killing tasks that already have pending fatal signals.
- Freezer doesn't care about tasks in different pid namespaces, i.e. if
you have two tasks in different pid namespaces the cgroup would still
be frozen. The cgroup.kill mechanism consequently behaves the same
way, i.e. we kill all processes and ignore in which pid namespace they
exist.
- If the caller is located in a cgroup that is killed the caller will
obviously be killed as well.
Link: https://lore.kernel.org/r/20210503143922.3093755-1-brauner@kernel.org
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: cgroups@vger.kernel.org
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Serge Hallyn <serge@hallyn.com>
Acked-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Rstat currently only supports the default hierarchy in cgroup2. In
order to replace memcg's private stats infrastructure - used in both
cgroup1 and cgroup2 - with rstat, the latter needs to support cgroup1.
The initialization and destruction callbacks for regular cgroups are
already in place. Remove the cgroup_on_dfl() guards to handle cgroup1.
The initialization of the root cgroup is currently hardcoded to only
handle cgrp_dfl_root.cgrp. Move those callbacks to cgroup_setup_root()
and cgroup_destroy_root() to handle the default root as well as the
various cgroup1 roots we may set up during mounting.
The linking of css to cgroups happens in code shared between cgroup1 and
cgroup2 as well. Simply remove the cgroup_on_dfl() guard.
Linkage of the root css to the root cgroup is a bit trickier: per
default, the root css of a subsystem controller belongs to the default
hierarchy (i.e. the cgroup2 root). When a controller is mounted in its
cgroup1 version, the root css is stolen and moved to the cgroup1 root;
on unmount, the css moves back to the default hierarchy. Annotate
rebind_subsystems() to move the root css linkage along between roots.
Link: https://lkml.kernel.org/r/20210209163304.77088-5-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Merge tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull idmapped mounts from Christian Brauner:
"This introduces idmapped mounts which has been in the making for some
time. Simply put, different mounts can expose the same file or
directory with different ownership. This initial implementation comes
with ports for fat, ext4 and with Christoph's port for xfs with more
filesystems being actively worked on by independent people and
maintainers.
Idmapping mounts handle a wide range of long standing use-cases. Here
are just a few:
- Idmapped mounts make it possible to easily share files between
multiple users or multiple machines especially in complex
scenarios. For example, idmapped mounts will be used in the
implementation of portable home directories in
systemd-homed.service(8) where they allow users to move their home
directory to an external storage device and use it on multiple
computers where they are assigned different uids and gids. This
effectively makes it possible to assign random uids and gids at
login time.
- It is possible to share files from the host with unprivileged
containers without having to change ownership permanently through
chown(2).
- It is possible to idmap a container's rootfs and without having to
mangle every file. For example, Chromebooks use it to share the
user's Download folder with their unprivileged containers in their
Linux subsystem.
- It is possible to share files between containers with
non-overlapping idmappings.
- Filesystem that lack a proper concept of ownership such as fat can
use idmapped mounts to implement discretionary access (DAC)
permission checking.
- They allow users to efficiently changing ownership on a per-mount
basis without having to (recursively) chown(2) all files. In
contrast to chown (2) changing ownership of large sets of files is
instantenous with idmapped mounts. This is especially useful when
ownership of a whole root filesystem of a virtual machine or
container is changed. With idmapped mounts a single syscall
mount_setattr syscall will be sufficient to change the ownership of
all files.
- Idmapped mounts always take the current ownership into account as
idmappings specify what a given uid or gid is supposed to be mapped
to. This contrasts with the chown(2) syscall which cannot by itself
take the current ownership of the files it changes into account. It
simply changes the ownership to the specified uid and gid. This is
especially problematic when recursively chown(2)ing a large set of
files which is commong with the aforementioned portable home
directory and container and vm scenario.
- Idmapped mounts allow to change ownership locally, restricting it
to specific mounts, and temporarily as the ownership changes only
apply as long as the mount exists.
Several userspace projects have either already put up patches and
pull-requests for this feature or will do so should you decide to pull
this:
- systemd: In a wide variety of scenarios but especially right away
in their implementation of portable home directories.
https://systemd.io/HOME_DIRECTORY/
- container runtimes: containerd, runC, LXD:To share data between
host and unprivileged containers, unprivileged and privileged
containers, etc. The pull request for idmapped mounts support in
containerd, the default Kubernetes runtime is already up for quite
a while now: https://github.com/containerd/containerd/pull/4734
- The virtio-fs developers and several users have expressed interest
in using this feature with virtual machines once virtio-fs is
ported.
- ChromeOS: Sharing host-directories with unprivileged containers.
I've tightly synced with all those projects and all of those listed
here have also expressed their need/desire for this feature on the
mailing list. For more info on how people use this there's a bunch of
talks about this too. Here's just two recent ones:
https://www.cncf.io/wp-content/uploads/2020/12/Rootless-Containers-in-Gitpod.pdfhttps://fosdem.org/2021/schedule/event/containers_idmap/
This comes with an extensive xfstests suite covering both ext4 and
xfs:
https://git.kernel.org/brauner/xfstests-dev/h/idmapped_mounts
It covers truncation, creation, opening, xattrs, vfscaps, setid
execution, setgid inheritance and more both with idmapped and
non-idmapped mounts. It already helped to discover an unrelated xfs
setgid inheritance bug which has since been fixed in mainline. It will
be sent for inclusion with the xfstests project should you decide to
merge this.
In order to support per-mount idmappings vfsmounts are marked with
user namespaces. The idmapping of the user namespace will be used to
map the ids of vfs objects when they are accessed through that mount.
By default all vfsmounts are marked with the initial user namespace.
The initial user namespace is used to indicate that a mount is not
idmapped. All operations behave as before and this is verified in the
testsuite.
Based on prior discussions we want to attach the whole user namespace
and not just a dedicated idmapping struct. This allows us to reuse all
the helpers that already exist for dealing with idmappings instead of
introducing a whole new range of helpers. In addition, if we decide in
the future that we are confident enough to enable unprivileged users
to setup idmapped mounts the permission checking can take into account
whether the caller is privileged in the user namespace the mount is
currently marked with.
The user namespace the mount will be marked with can be specified by
passing a file descriptor refering to the user namespace as an
argument to the new mount_setattr() syscall together with the new
MOUNT_ATTR_IDMAP flag. The system call follows the openat2() pattern
of extensibility.
The following conditions must be met in order to create an idmapped
mount:
- The caller must currently have the CAP_SYS_ADMIN capability in the
user namespace the underlying filesystem has been mounted in.
- The underlying filesystem must support idmapped mounts.
- The mount must not already be idmapped. This also implies that the
idmapping of a mount cannot be altered once it has been idmapped.
- The mount must be a detached/anonymous mount, i.e. it must have
been created by calling open_tree() with the OPEN_TREE_CLONE flag
and it must not already have been visible in the filesystem.
The last two points guarantee easier semantics for userspace and the
kernel and make the implementation significantly simpler.
By default vfsmounts are marked with the initial user namespace and no
behavioral or performance changes are observed.
The manpage with a detailed description can be found here:
1d7b902e28
In order to support idmapped mounts, filesystems need to be changed
and mark themselves with the FS_ALLOW_IDMAP flag in fs_flags. The
patches to convert individual filesystem are not very large or
complicated overall as can be seen from the included fat, ext4, and
xfs ports. Patches for other filesystems are actively worked on and
will be sent out separately. The xfstestsuite can be used to verify
that port has been done correctly.
The mount_setattr() syscall is motivated independent of the idmapped
mounts patches and it's been around since July 2019. One of the most
valuable features of the new mount api is the ability to perform
mounts based on file descriptors only.
Together with the lookup restrictions available in the openat2()
RESOLVE_* flag namespace which we added in v5.6 this is the first time
we are close to hardened and race-free (e.g. symlinks) mounting and
path resolution.
While userspace has started porting to the new mount api to mount
proper filesystems and create new bind-mounts it is currently not
possible to change mount options of an already existing bind mount in
the new mount api since the mount_setattr() syscall is missing.
With the addition of the mount_setattr() syscall we remove this last
restriction and userspace can now fully port to the new mount api,
covering every use-case the old mount api could. We also add the
crucial ability to recursively change mount options for a whole mount
tree, both removing and adding mount options at the same time. This
syscall has been requested multiple times by various people and
projects.
There is a simple tool available at
https://github.com/brauner/mount-idmapped
that allows to create idmapped mounts so people can play with this
patch series. I'll add support for the regular mount binary should you
decide to pull this in the following weeks:
Here's an example to a simple idmapped mount of another user's home
directory:
u1001@f2-vm:/$ sudo ./mount --idmap both:1000:1001:1 /home/ubuntu/ /mnt
u1001@f2-vm:/$ ls -al /home/ubuntu/
total 28
drwxr-xr-x 2 ubuntu ubuntu 4096 Oct 28 22:07 .
drwxr-xr-x 4 root root 4096 Oct 28 04:00 ..
-rw------- 1 ubuntu ubuntu 3154 Oct 28 22:12 .bash_history
-rw-r--r-- 1 ubuntu ubuntu 220 Feb 25 2020 .bash_logout
-rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25 2020 .bashrc
-rw-r--r-- 1 ubuntu ubuntu 807 Feb 25 2020 .profile
-rw-r--r-- 1 ubuntu ubuntu 0 Oct 16 16:11 .sudo_as_admin_successful
-rw------- 1 ubuntu ubuntu 1144 Oct 28 00:43 .viminfo
u1001@f2-vm:/$ ls -al /mnt/
total 28
drwxr-xr-x 2 u1001 u1001 4096 Oct 28 22:07 .
drwxr-xr-x 29 root root 4096 Oct 28 22:01 ..
-rw------- 1 u1001 u1001 3154 Oct 28 22:12 .bash_history
-rw-r--r-- 1 u1001 u1001 220 Feb 25 2020 .bash_logout
-rw-r--r-- 1 u1001 u1001 3771 Feb 25 2020 .bashrc
-rw-r--r-- 1 u1001 u1001 807 Feb 25 2020 .profile
-rw-r--r-- 1 u1001 u1001 0 Oct 16 16:11 .sudo_as_admin_successful
-rw------- 1 u1001 u1001 1144 Oct 28 00:43 .viminfo
u1001@f2-vm:/$ touch /mnt/my-file
u1001@f2-vm:/$ setfacl -m u:1001:rwx /mnt/my-file
u1001@f2-vm:/$ sudo setcap -n 1001 cap_net_raw+ep /mnt/my-file
u1001@f2-vm:/$ ls -al /mnt/my-file
-rw-rwxr--+ 1 u1001 u1001 0 Oct 28 22:14 /mnt/my-file
u1001@f2-vm:/$ ls -al /home/ubuntu/my-file
-rw-rwxr--+ 1 ubuntu ubuntu 0 Oct 28 22:14 /home/ubuntu/my-file
u1001@f2-vm:/$ getfacl /mnt/my-file
getfacl: Removing leading '/' from absolute path names
# file: mnt/my-file
# owner: u1001
# group: u1001
user::rw-
user:u1001:rwx
group::rw-
mask::rwx
other::r--
u1001@f2-vm:/$ getfacl /home/ubuntu/my-file
getfacl: Removing leading '/' from absolute path names
# file: home/ubuntu/my-file
# owner: ubuntu
# group: ubuntu
user::rw-
user:ubuntu:rwx
group::rw-
mask::rwx
other::r--"
* tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: (41 commits)
xfs: remove the possibly unused mp variable in xfs_file_compat_ioctl
xfs: support idmapped mounts
ext4: support idmapped mounts
fat: handle idmapped mounts
tests: add mount_setattr() selftests
fs: introduce MOUNT_ATTR_IDMAP
fs: add mount_setattr()
fs: add attr_flags_to_mnt_flags helper
fs: split out functions to hold writers
namespace: only take read lock in do_reconfigure_mnt()
mount: make {lock,unlock}_mount_hash() static
namespace: take lock_mount_hash() directly when changing flags
nfs: do not export idmapped mounts
overlayfs: do not mount on top of idmapped mounts
ecryptfs: do not mount on top of idmapped mounts
ima: handle idmapped mounts
apparmor: handle idmapped mounts
fs: make helpers idmap mount aware
exec: handle idmapped mounts
would_dump: handle idmapped mounts
...
Pull cgroup updates from Tejun Heo:
"Nothing interesting. Just two minor patches"
* 'for-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cpuset: fix typos in comments
cgroup: cgroup.{procs,threads} factor out common parts
The two helpers inode_permission() and generic_permission() are used by
the vfs to perform basic permission checking by verifying that the
caller is privileged over an inode. In order to handle idmapped mounts
we extend the two helpers with an additional user namespace argument.
On idmapped mounts the two helpers will make sure to map the inode
according to the mount's user namespace and then peform identical
permission checks to inode_permission() and generic_permission(). If the
initial user namespace is passed nothing changes so non-idmapped mounts
will see identical behavior as before.
Link: https://lore.kernel.org/r/20210121131959.646623-6-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Fix NULL pointer dereference when adding new psi monitor to the root
cgroup. PSI files for root cgroup was introduced in df5ba5be74 by using
system wide psi struct when reading, but file write/monitor was not
properly fixed. Since the PSI config for the root cgroup isn't
initialized, the current implementation tries to lock a NULL ptr,
resulting in a crash.
Can be triggered by running this as root:
$ tee /sys/fs/cgroup/cpu.pressure <<< "some 10000 1000000"
Signed-off-by: Odin Ugedal <odin@uged.al>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Dan Schatzberg <dschatzberg@fb.com>
Fixes: df5ba5be74 ("kernel/sched/psi.c: expose pressure metrics on root cgroup")
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: stable@vger.kernel.org # 5.2+
Signed-off-by: Tejun Heo <tj@kernel.org>
The functions cgroup_threads_write and cgroup_procs_write are almost
identical. In order to reduce duplication, factor out the common code in
similar fashion we already do for other threadgroup/task functions. No
functional changes are intended.
Suggested-by: Hao Lee <haolee.swjtu@gmail.com>
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Pull cgroup updates from Tejun Heo:
"These three patches were scheduled for the merge window but I forgot
to send them out. Sorry about that.
None of them are significant and they fit well in a fix pull request
too - two are cosmetic and one fixes a memory leak in the mount option
parsing path"
* 'for-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: Fix memory leak when parsing multiple source parameters
cgroup/cgroup.c: replace 'of->kn->priv' with of_cft()
kernel: cgroup: Mundane spelling fixes throughout the file
Merge misc updates from Andrew Morton:
- a few random little subsystems
- almost all of the MM patches which are staged ahead of linux-next
material. I'll trickle to post-linux-next work in as the dependents
get merged up.
Subsystems affected by this patch series: kthread, kbuild, ide, ntfs,
ocfs2, arch, and mm (slab-generic, slab, slub, dax, debug, pagecache,
gup, swap, shmem, memcg, pagemap, mremap, hmm, vmalloc, documentation,
kasan, pagealloc, memory-failure, hugetlb, vmscan, z3fold, compaction,
oom-kill, migration, cma, page-poison, userfaultfd, zswap, zsmalloc,
uaccess, zram, and cleanups).
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (200 commits)
mm: cleanup kstrto*() usage
mm: fix fall-through warnings for Clang
mm: slub: convert sysfs sprintf family to sysfs_emit/sysfs_emit_at
mm: shmem: convert shmem_enabled_show to use sysfs_emit_at
mm:backing-dev: use sysfs_emit in macro defining functions
mm: huge_memory: convert remaining use of sprintf to sysfs_emit and neatening
mm: use sysfs_emit for struct kobject * uses
mm: fix kernel-doc markups
zram: break the strict dependency from lzo
zram: add stat to gather incompressible pages since zram set up
zram: support page writeback
mm/process_vm_access: remove redundant initialization of iov_r
mm/zsmalloc.c: rework the list_add code in insert_zspage()
mm/zswap: move to use crypto_acomp API for hardware acceleration
mm/zswap: fix passing zero to 'PTR_ERR' warning
mm/zswap: make struct kernel_param_ops definitions const
userfaultfd/selftests: hint the test runner on required privilege
userfaultfd/selftests: fix retval check for userfaultfd_open()
userfaultfd/selftests: always dump something in modes
userfaultfd: selftests: make __{s,u}64 format specifiers portable
...
With the deprecation of the non-hierarchical mode of the memory controller
there are no more examples of broken hierarchies left.
Let's remove the cgroup core code which was supposed to print warnings
about creating of broken hierarchies.
Link: https://lkml.kernel.org/r/20201110220800.929549-4-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "mm: memcg: deprecate cgroup v1 non-hierarchical mode", v1.
The non-hierarchical cgroup v1 mode is a legacy of early days
of the memory controller and doesn't bring any value today.
However, it complicates the code and creates many edge cases
all over the memory controller code.
It's a good time to deprecate it completely. This patchset removes
the internal logic, adjusts the user interface and updates
the documentation. The alt patch removes some bits of the cgroup
core code, which become obsolete.
Michal Hocko said:
"All that we know today is that we have a warning in place to complain
loudly when somebody relies on use_hierarchy=0 with a deeper
hierarchy. For all those years we have seen _zero_ reports that would
describe a sensible usecase.
Moreover we (SUSE) have backported this warning into old distribution
kernels (since 3.0 based kernels) to extend the coverage and didn't
hear even for users who adopt new kernels only very slowly. The only
report we have seen so far was a LTP test suite which doesn't really
reflect any real life usecase"
This patch (of 3):
The non-hierarchical cgroup v1 mode is a legacy of early days of the
memory controller and doesn't bring any value today. However, it
complicates the code and creates many edge cases all over the memory
controller code.
It's a good time to deprecate it completely.
Functionally this patch enabled is by default for all cgroups and forbids
switching it off. Nothing changes if cgroup v2 is used: hierarchical mode
was enforced from scratch.
To protect the ABI memory.use_hierarchy interface is preserved with a
limited functionality: reading always returns "1", writing of "1" passes
silently, writing of any other value fails with -EINVAL and a warning to
dmesg (on the first occasion).
Link: https://lkml.kernel.org/r/20201110220800.929549-1-guro@fb.com
Link: https://lkml.kernel.org/r/20201110220800.929549-2-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Merge tag 'fixes-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull misc fixes from Christian Brauner:
"This contains several fixes which felt worth being combined into a
single branch:
- Use put_nsproxy() instead of open-coding it switch_task_namespaces()
- Kirill's work to unify lifecycle management for all namespaces. The
lifetime counters are used identically for all namespaces types.
Namespaces may of course have additional unrelated counters and
these are not altered. This work allows us to unify the type of the
counters and reduces maintenance cost by moving the counter in one
place and indicating that basic lifetime management is identical
for all namespaces.
- Peilin's fix adding three byte padding to Dmitry's
PTRACE_GET_SYSCALL_INFO uapi struct to prevent an info leak.
- Two smal patches to convert from the /* fall through */ comment
annotation to the fallthrough keyword annotation which I had taken
into my branch and into -next before df561f6688 ("treewide: Use
fallthrough pseudo-keyword") made it upstream which fixed this
tree-wide.
Since I didn't want to invalidate all testing for other commits I
didn't rebase and kept them"
* tag 'fixes-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
nsproxy: use put_nsproxy() in switch_task_namespaces()
sys: Convert to the new fallthrough notation
signal: Convert to the new fallthrough notation
time: Use generic ns_common::count
cgroup: Use generic ns_common::count
mnt: Use generic ns_common::count
user: Use generic ns_common::count
pid: Use generic ns_common::count
ipc: Use generic ns_common::count
uts: Use generic ns_common::count
net: Use generic ns_common::count
ns: Add a common refcount into ns_common
ptrace: Prevent kernel-infoleak in ptrace_get_syscall_info()
we have supplied the inline function: of_cft() in cgroup.h.
So replace the direct use 'of->kn->priv' with inline func
of_cft(), which is more readable.
Signed-off-by: Hui Su <sh_def@163.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Do not report failure on zero sized writes, and handle them as no-op.
There's issues for example in case of writev() when there's iovec
containing zero buffer as a first one. It's expected writev() on below
example to successfully perform the write to specified writable cgroup
file expecting integer value, and to return 2. For now it's returning
value -1, and skipping the write:
int writetest(int fd) {
const char *buf1 = "";
const char *buf2 = "1\n";
struct iovec iov[2] = {
{ .iov_base = (void*)buf1, .iov_len = 0 },
{ .iov_base = (void*)buf2, .iov_len = 2 }
};
return writev(fd, iov, 2);
}
This patch fixes the issue by checking if there's nothing to write,
and handling the write as no-op by just returning 0.
Signed-off-by: Jouni Roivas <jouni.roivas@tuxera.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This step is already done in rebind_subsystems().
Not necessary to do it again.
Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Switch over cgroup namespaces to use the newly introduced common lifetime
counter.
Currently every namespace type has its own lifetime counter which is stored
in the specific namespace struct. The lifetime counters are used
identically for all namespaces types. Namespaces may of course have
additional unrelated counters and these are not altered.
This introduces a common lifetime counter into struct ns_common. The
ns_common struct encompasses information that all namespaces share. That
should include the lifetime counter since its common for all of them.
It also allows us to unify the type of the counters across all namespaces.
Most of them use refcount_t but one uses atomic_t and at least one uses
kref. Especially the last one doesn't make much sense since it's just a
wrapper around refcount_t since 2016 and actually complicates cleanup
operations by having to use container_of() to cast the correct namespace
struct out of struct ns_common.
Having the lifetime counter for the namespaces in one place reduces
maintenance cost. Not just because after switching all namespaces over we
will have removed more code than we added but also because the logic is
more easily understandable and we indicate to the user that the basic
lifetime requirements for all namespaces are currently identical.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/159644980994.604812.383801057081594972.stgit@localhost.localdomain
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
When we clone a socket in sk_clone_lock(), its sk_cgrp_data is
copied, so the cgroup refcnt must be taken too. And, unlike the
sk_alloc() path, sock_update_netprioidx() is not called here.
Therefore, it is safe and necessary to grab the cgroup refcnt
even when cgroup_sk_alloc is disabled.
sk_clone_lock() is in BH context anyway, the in_interrupt()
would terminate this function if called there. And for sk_alloc()
skcd->val is always zero. So it's safe to factor out the code
to make it more readable.
The global variable 'cgroup_sk_alloc_disabled' is used to determine
whether to take these reference counts. It is impossible to make
the reference counting correct unless we save this bit of information
in skcd->val. So, add a new bit there to record whether the socket
has already taken the reference counts. This obviously relies on
kmalloc() to align cgroup pointers to at least 4 bytes,
ARCH_KMALLOC_MINALIGN is certainly larger than that.
This bug seems to be introduced since the beginning, commit
d979a39d72 ("cgroup: duplicate cgroup reference when cloning sockets")
tried to fix it but not compeletely. It seems not easy to trigger until
the recent commit 090e28b229
("netprio_cgroup: Fix unlimited memory leak of v2 cgroups") was merged.
Fixes: bd1060a1d6 ("sock, cgroup: add sock->sk_cgroup")
Reported-by: Cameron Berkenpas <cam@neo-zeon.de>
Reported-by: Peter Geis <pgwipeout@gmail.com>
Reported-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reported-by: Daniël Sonck <dsonck92@gmail.com>
Reported-by: Zhang Qiang <qiang.zhang@windriver.com>
Tested-by: Cameron Berkenpas <cam@neo-zeon.de>
Tested-by: Peter Geis <pgwipeout@gmail.com>
Tested-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Zefan Li <lizefan@huawei.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Roman Gushchin <guro@fb.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull cgroup updates from Tejun Heo:
"Just two patches: one to add system-level cpu.stat to the root cgroup
for convenience and a trivial comment update"
* 'for-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: add cpu.stat file to root cgroup
cgroup: Remove stale comments
Currently, the root cgroup does not have a cpu.stat file. Add one which
is consistent with /proc/stat to capture global cpu statistics that
might not fall under cgroup accounting.
We haven't done this in the past because the data are already presented
in /proc/stat and we didn't want to add overhead from collecting root
cgroup stats when cgroups are configured, but no cgroups have been
created.
By keeping the data consistent with /proc/stat, I think we avoid the
first problem, while improving the usability of cgroups stats.
We avoid the second problem by computing the contents of cpu.stat from
existing data collected for /proc/stat anyway.
Signed-off-by: Boris Burkov <boris@bur.io>
Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
- The default root is where we can create v2 cgroups.
- The __DEVEL__sane_behavior mount option has been removed long long ago.
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Make bpf_link update support more generic by making it into another
bpf_link_ops methods. This allows generic syscall handling code to be agnostic
to various conditionally compiled features (e.g., the case of
CONFIG_CGROUP_BPF). This also allows to keep link type-specific code to remain
static within respective code base. Refactor existing bpf_cgroup_link code and
take advantage of this.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200429001614.1544-2-andriin@fb.com
